1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Low-level parallel port routines for built-in port on SGI IP32
3  *
4  * Author: Arnaud Giersch <arnaud.giersch@free.fr>
5  *
6  * Based on parport_pc.c by
7  *	Phil Blundell, Tim Waugh, Jose Renau, David Campbell,
8  *	Andrea Arcangeli, et al.
9  *
10  * Thanks to Ilya A. Volynets-Evenbakh for his help.
11  *
12  * Copyright (C) 2005, 2006 Arnaud Giersch.
13  */
14 
15 /* Current status:
16  *
17  *	Basic SPP and PS2 modes are supported.
18  *	Support for parallel port IRQ is present.
19  *	Hardware SPP (a.k.a. compatibility), EPP, and ECP modes are
20  *	supported.
21  *	SPP/ECP FIFO can be driven in PIO or DMA mode.  PIO mode can work with
22  *	or without interrupt support.
23  *
24  *	Hardware ECP mode is not fully implemented (ecp_read_data and
25  *	ecp_write_addr are actually missing).
26  *
27  * To do:
28  *
29  *	Fully implement ECP mode.
30  *	EPP and ECP mode need to be tested.  I currently do not own any
31  *	peripheral supporting these extended mode, and cannot test them.
32  *	If DMA mode works well, decide if support for PIO FIFO modes should be
33  *	dropped.
34  *	Use the io{read,write} family functions when they become available in
35  *	the linux-mips.org tree.  Note: the MIPS specific functions readsb()
36  *	and writesb() are to be translated by ioread8_rep() and iowrite8_rep()
37  *	respectively.
38  */
39 
40 /* The built-in parallel port on the SGI 02 workstation (a.k.a. IP32) is an
41  * IEEE 1284 parallel port driven by a Texas Instrument TL16PIR552PH chip[1].
42  * This chip supports SPP, bidirectional, EPP and ECP modes.  It has a 16 byte
43  * FIFO buffer and supports DMA transfers.
44  *
45  * [1] http://focus.ti.com/docs/prod/folders/print/tl16pir552.html
46  *
47  * Theoretically, we could simply use the parport_pc module.  It is however
48  * not so simple.  The parport_pc code assumes that the parallel port
49  * registers are port-mapped.  On the O2, they are memory-mapped.
50  * Furthermore, each register is replicated on 256 consecutive addresses (as
51  * it is for the built-in serial ports on the same chip).
52  */
53 
54 /*--- Some configuration defines ---------------------------------------*/
55 
56 /* DEBUG_PARPORT_IP32
57  *	0	disable debug
58  *	1	standard level: pr_debug1 is enabled
59  *	2	parport_ip32_dump_state is enabled
60  *	>=3	verbose level: pr_debug is enabled
61  */
62 #if !defined(DEBUG_PARPORT_IP32)
63 #	define DEBUG_PARPORT_IP32  0	/* 0 (disabled) for production */
64 #endif
65 
66 /*----------------------------------------------------------------------*/
67 
68 /* Setup DEBUG macros.  This is done before any includes, just in case we
69  * activate pr_debug() with DEBUG_PARPORT_IP32 >= 3.
70  */
71 #if DEBUG_PARPORT_IP32 == 1
72 #	warning DEBUG_PARPORT_IP32 == 1
73 #elif DEBUG_PARPORT_IP32 == 2
74 #	warning DEBUG_PARPORT_IP32 == 2
75 #elif DEBUG_PARPORT_IP32 >= 3
76 #	warning DEBUG_PARPORT_IP32 >= 3
77 #	if !defined(DEBUG)
78 #		define DEBUG /* enable pr_debug() in kernel.h */
79 #	endif
80 #endif
81 
82 #include <linux/completion.h>
83 #include <linux/delay.h>
84 #include <linux/dma-mapping.h>
85 #include <linux/err.h>
86 #include <linux/init.h>
87 #include <linux/interrupt.h>
88 #include <linux/jiffies.h>
89 #include <linux/kernel.h>
90 #include <linux/module.h>
91 #include <linux/parport.h>
92 #include <linux/sched/signal.h>
93 #include <linux/slab.h>
94 #include <linux/spinlock.h>
95 #include <linux/stddef.h>
96 #include <linux/types.h>
97 #include <asm/io.h>
98 #include <asm/ip32/ip32_ints.h>
99 #include <asm/ip32/mace.h>
100 
101 /*--- Global variables -------------------------------------------------*/
102 
103 /* Verbose probing on by default for debugging. */
104 #if DEBUG_PARPORT_IP32 >= 1
105 #	define DEFAULT_VERBOSE_PROBING	1
106 #else
107 #	define DEFAULT_VERBOSE_PROBING	0
108 #endif
109 
110 /* Default prefix for printk */
111 #define PPIP32 "parport_ip32: "
112 
113 /*
114  * These are the module parameters:
115  * @features:		bit mask of features to enable/disable
116  *			(all enabled by default)
117  * @verbose_probing:	log chit-chat during initialization
118  */
119 #define PARPORT_IP32_ENABLE_IRQ	(1U << 0)
120 #define PARPORT_IP32_ENABLE_DMA	(1U << 1)
121 #define PARPORT_IP32_ENABLE_SPP	(1U << 2)
122 #define PARPORT_IP32_ENABLE_EPP	(1U << 3)
123 #define PARPORT_IP32_ENABLE_ECP	(1U << 4)
124 static unsigned int features =	~0U;
125 static bool verbose_probing =	DEFAULT_VERBOSE_PROBING;
126 
127 /* We do not support more than one port. */
128 static struct parport *this_port;
129 
130 /* Timing constants for FIFO modes.  */
131 #define FIFO_NFAULT_TIMEOUT	100	/* milliseconds */
132 #define FIFO_POLLING_INTERVAL	50	/* microseconds */
133 
134 /*--- I/O register definitions -----------------------------------------*/
135 
136 /**
137  * struct parport_ip32_regs - virtual addresses of parallel port registers
138  * @data:	Data Register
139  * @dsr:	Device Status Register
140  * @dcr:	Device Control Register
141  * @eppAddr:	EPP Address Register
142  * @eppData0:	EPP Data Register 0
143  * @eppData1:	EPP Data Register 1
144  * @eppData2:	EPP Data Register 2
145  * @eppData3:	EPP Data Register 3
146  * @ecpAFifo:	ECP Address FIFO
147  * @fifo:	General FIFO register.  The same address is used for:
148  *		- cFifo, the Parallel Port DATA FIFO
149  *		- ecpDFifo, the ECP Data FIFO
150  *		- tFifo, the ECP Test FIFO
151  * @cnfgA:	Configuration Register A
152  * @cnfgB:	Configuration Register B
153  * @ecr:	Extended Control Register
154  */
155 struct parport_ip32_regs {
156 	void __iomem *data;
157 	void __iomem *dsr;
158 	void __iomem *dcr;
159 	void __iomem *eppAddr;
160 	void __iomem *eppData0;
161 	void __iomem *eppData1;
162 	void __iomem *eppData2;
163 	void __iomem *eppData3;
164 	void __iomem *ecpAFifo;
165 	void __iomem *fifo;
166 	void __iomem *cnfgA;
167 	void __iomem *cnfgB;
168 	void __iomem *ecr;
169 };
170 
171 /* Device Status Register */
172 #define DSR_nBUSY		(1U << 7)	/* PARPORT_STATUS_BUSY */
173 #define DSR_nACK		(1U << 6)	/* PARPORT_STATUS_ACK */
174 #define DSR_PERROR		(1U << 5)	/* PARPORT_STATUS_PAPEROUT */
175 #define DSR_SELECT		(1U << 4)	/* PARPORT_STATUS_SELECT */
176 #define DSR_nFAULT		(1U << 3)	/* PARPORT_STATUS_ERROR */
177 #define DSR_nPRINT		(1U << 2)	/* specific to TL16PIR552 */
178 /* #define DSR_reserved		(1U << 1) */
179 #define DSR_TIMEOUT		(1U << 0)	/* EPP timeout */
180 
181 /* Device Control Register */
182 /* #define DCR_reserved		(1U << 7) | (1U <<  6) */
183 #define DCR_DIR			(1U << 5)	/* direction */
184 #define DCR_IRQ			(1U << 4)	/* interrupt on nAck */
185 #define DCR_SELECT		(1U << 3)	/* PARPORT_CONTROL_SELECT */
186 #define DCR_nINIT		(1U << 2)	/* PARPORT_CONTROL_INIT */
187 #define DCR_AUTOFD		(1U << 1)	/* PARPORT_CONTROL_AUTOFD */
188 #define DCR_STROBE		(1U << 0)	/* PARPORT_CONTROL_STROBE */
189 
190 /* ECP Configuration Register A */
191 #define CNFGA_IRQ		(1U << 7)
192 #define CNFGA_ID_MASK		((1U << 6) | (1U << 5) | (1U << 4))
193 #define CNFGA_ID_SHIFT		4
194 #define CNFGA_ID_16		(00U << CNFGA_ID_SHIFT)
195 #define CNFGA_ID_8		(01U << CNFGA_ID_SHIFT)
196 #define CNFGA_ID_32		(02U << CNFGA_ID_SHIFT)
197 /* #define CNFGA_reserved	(1U << 3) */
198 #define CNFGA_nBYTEINTRANS	(1U << 2)
199 #define CNFGA_PWORDLEFT		((1U << 1) | (1U << 0))
200 
201 /* ECP Configuration Register B */
202 #define CNFGB_COMPRESS		(1U << 7)
203 #define CNFGB_INTRVAL		(1U << 6)
204 #define CNFGB_IRQ_MASK		((1U << 5) | (1U << 4) | (1U << 3))
205 #define CNFGB_IRQ_SHIFT		3
206 #define CNFGB_DMA_MASK		((1U << 2) | (1U << 1) | (1U << 0))
207 #define CNFGB_DMA_SHIFT		0
208 
209 /* Extended Control Register */
210 #define ECR_MODE_MASK		((1U << 7) | (1U << 6) | (1U << 5))
211 #define ECR_MODE_SHIFT		5
212 #define ECR_MODE_SPP		(00U << ECR_MODE_SHIFT)
213 #define ECR_MODE_PS2		(01U << ECR_MODE_SHIFT)
214 #define ECR_MODE_PPF		(02U << ECR_MODE_SHIFT)
215 #define ECR_MODE_ECP		(03U << ECR_MODE_SHIFT)
216 #define ECR_MODE_EPP		(04U << ECR_MODE_SHIFT)
217 /* #define ECR_MODE_reserved	(05U << ECR_MODE_SHIFT) */
218 #define ECR_MODE_TST		(06U << ECR_MODE_SHIFT)
219 #define ECR_MODE_CFG		(07U << ECR_MODE_SHIFT)
220 #define ECR_nERRINTR		(1U << 4)
221 #define ECR_DMAEN		(1U << 3)
222 #define ECR_SERVINTR		(1U << 2)
223 #define ECR_F_FULL		(1U << 1)
224 #define ECR_F_EMPTY		(1U << 0)
225 
226 /*--- Private data -----------------------------------------------------*/
227 
228 /**
229  * enum parport_ip32_irq_mode - operation mode of interrupt handler
230  * @PARPORT_IP32_IRQ_FWD:	forward interrupt to the upper parport layer
231  * @PARPORT_IP32_IRQ_HERE:	interrupt is handled locally
232  */
233 enum parport_ip32_irq_mode { PARPORT_IP32_IRQ_FWD, PARPORT_IP32_IRQ_HERE };
234 
235 /**
236  * struct parport_ip32_private - private stuff for &struct parport
237  * @regs:		register addresses
238  * @dcr_cache:		cached contents of DCR
239  * @dcr_writable:	bit mask of writable DCR bits
240  * @pword:		number of bytes per PWord
241  * @fifo_depth:		number of PWords that FIFO will hold
242  * @readIntrThreshold:	minimum number of PWords we can read
243  *			if we get an interrupt
244  * @writeIntrThreshold:	minimum number of PWords we can write
245  *			if we get an interrupt
246  * @irq_mode:		operation mode of interrupt handler for this port
247  * @irq_complete:	mutex used to wait for an interrupt to occur
248  */
249 struct parport_ip32_private {
250 	struct parport_ip32_regs	regs;
251 	unsigned int			dcr_cache;
252 	unsigned int			dcr_writable;
253 	unsigned int			pword;
254 	unsigned int			fifo_depth;
255 	unsigned int			readIntrThreshold;
256 	unsigned int			writeIntrThreshold;
257 	enum parport_ip32_irq_mode	irq_mode;
258 	struct completion		irq_complete;
259 };
260 
261 /*--- Debug code -------------------------------------------------------*/
262 
263 /*
264  * pr_debug1 - print debug messages
265  *
266  * This is like pr_debug(), but is defined for %DEBUG_PARPORT_IP32 >= 1
267  */
268 #if DEBUG_PARPORT_IP32 >= 1
269 #	define pr_debug1(...)	printk(KERN_DEBUG __VA_ARGS__)
270 #else /* DEBUG_PARPORT_IP32 < 1 */
271 #	define pr_debug1(...)	do { } while (0)
272 #endif
273 
274 /*
275  * pr_trace, pr_trace1 - trace function calls
276  * @p:		pointer to &struct parport
277  * @fmt:	printk format string
278  * @...:	parameters for format string
279  *
280  * Macros used to trace function calls.  The given string is formatted after
281  * function name.  pr_trace() uses pr_debug(), and pr_trace1() uses
282  * pr_debug1().  __pr_trace() is the low-level macro and is not to be used
283  * directly.
284  */
285 #define __pr_trace(pr, p, fmt, ...)					\
286 	pr("%s: %s" fmt "\n",						\
287 	   ({ const struct parport *__p = (p);				\
288 		   __p ? __p->name : "parport_ip32"; }),		\
289 	   __func__ , ##__VA_ARGS__)
290 #define pr_trace(p, fmt, ...)	__pr_trace(pr_debug, p, fmt , ##__VA_ARGS__)
291 #define pr_trace1(p, fmt, ...)	__pr_trace(pr_debug1, p, fmt , ##__VA_ARGS__)
292 
293 /*
294  * __pr_probe, pr_probe - print message if @verbose_probing is true
295  * @p:		pointer to &struct parport
296  * @fmt:	printk format string
297  * @...:	parameters for format string
298  *
299  * For new lines, use pr_probe().  Use __pr_probe() for continued lines.
300  */
301 #define __pr_probe(...)							\
302 	do { if (verbose_probing) printk(__VA_ARGS__); } while (0)
303 #define pr_probe(p, fmt, ...)						\
304 	__pr_probe(KERN_INFO PPIP32 "0x%lx: " fmt, (p)->base , ##__VA_ARGS__)
305 
306 /*
307  * parport_ip32_dump_state - print register status of parport
308  * @p:		pointer to &struct parport
309  * @str:	string to add in message
310  * @show_ecp_config:	shall we dump ECP configuration registers too?
311  *
312  * This function is only here for debugging purpose, and should be used with
313  * care.  Reading the parallel port registers may have undesired side effects.
314  * Especially if @show_ecp_config is true, the parallel port is resetted.
315  * This function is only defined if %DEBUG_PARPORT_IP32 >= 2.
316  */
317 #if DEBUG_PARPORT_IP32 >= 2
318 static void parport_ip32_dump_state(struct parport *p, char *str,
319 				    unsigned int show_ecp_config)
320 {
321 	struct parport_ip32_private * const priv = p->physport->private_data;
322 	unsigned int i;
323 
324 	printk(KERN_DEBUG PPIP32 "%s: state (%s):\n", p->name, str);
325 	{
326 		static const char ecr_modes[8][4] = {"SPP", "PS2", "PPF",
327 						     "ECP", "EPP", "???",
328 						     "TST", "CFG"};
329 		unsigned int ecr = readb(priv->regs.ecr);
330 		printk(KERN_DEBUG PPIP32 "    ecr=0x%02x", ecr);
331 		printk(" %s",
332 		       ecr_modes[(ecr & ECR_MODE_MASK) >> ECR_MODE_SHIFT]);
333 		if (ecr & ECR_nERRINTR)
334 			printk(",nErrIntrEn");
335 		if (ecr & ECR_DMAEN)
336 			printk(",dmaEn");
337 		if (ecr & ECR_SERVINTR)
338 			printk(",serviceIntr");
339 		if (ecr & ECR_F_FULL)
340 			printk(",f_full");
341 		if (ecr & ECR_F_EMPTY)
342 			printk(",f_empty");
343 		printk("\n");
344 	}
345 	if (show_ecp_config) {
346 		unsigned int oecr, cnfgA, cnfgB;
347 		oecr = readb(priv->regs.ecr);
348 		writeb(ECR_MODE_PS2, priv->regs.ecr);
349 		writeb(ECR_MODE_CFG, priv->regs.ecr);
350 		cnfgA = readb(priv->regs.cnfgA);
351 		cnfgB = readb(priv->regs.cnfgB);
352 		writeb(ECR_MODE_PS2, priv->regs.ecr);
353 		writeb(oecr, priv->regs.ecr);
354 		printk(KERN_DEBUG PPIP32 "    cnfgA=0x%02x", cnfgA);
355 		printk(" ISA-%s", (cnfgA & CNFGA_IRQ) ? "Level" : "Pulses");
356 		switch (cnfgA & CNFGA_ID_MASK) {
357 		case CNFGA_ID_8:
358 			printk(",8 bits");
359 			break;
360 		case CNFGA_ID_16:
361 			printk(",16 bits");
362 			break;
363 		case CNFGA_ID_32:
364 			printk(",32 bits");
365 			break;
366 		default:
367 			printk(",unknown ID");
368 			break;
369 		}
370 		if (!(cnfgA & CNFGA_nBYTEINTRANS))
371 			printk(",ByteInTrans");
372 		if ((cnfgA & CNFGA_ID_MASK) != CNFGA_ID_8)
373 			printk(",%d byte%s left", cnfgA & CNFGA_PWORDLEFT,
374 			       ((cnfgA & CNFGA_PWORDLEFT) > 1) ? "s" : "");
375 		printk("\n");
376 		printk(KERN_DEBUG PPIP32 "    cnfgB=0x%02x", cnfgB);
377 		printk(" irq=%u,dma=%u",
378 		       (cnfgB & CNFGB_IRQ_MASK) >> CNFGB_IRQ_SHIFT,
379 		       (cnfgB & CNFGB_DMA_MASK) >> CNFGB_DMA_SHIFT);
380 		printk(",intrValue=%d", !!(cnfgB & CNFGB_INTRVAL));
381 		if (cnfgB & CNFGB_COMPRESS)
382 			printk(",compress");
383 		printk("\n");
384 	}
385 	for (i = 0; i < 2; i++) {
386 		unsigned int dcr = i ? priv->dcr_cache : readb(priv->regs.dcr);
387 		printk(KERN_DEBUG PPIP32 "    dcr(%s)=0x%02x",
388 		       i ? "soft" : "hard", dcr);
389 		printk(" %s", (dcr & DCR_DIR) ? "rev" : "fwd");
390 		if (dcr & DCR_IRQ)
391 			printk(",ackIntEn");
392 		if (!(dcr & DCR_SELECT))
393 			printk(",nSelectIn");
394 		if (dcr & DCR_nINIT)
395 			printk(",nInit");
396 		if (!(dcr & DCR_AUTOFD))
397 			printk(",nAutoFD");
398 		if (!(dcr & DCR_STROBE))
399 			printk(",nStrobe");
400 		printk("\n");
401 	}
402 #define sep (f++ ? ',' : ' ')
403 	{
404 		unsigned int f = 0;
405 		unsigned int dsr = readb(priv->regs.dsr);
406 		printk(KERN_DEBUG PPIP32 "    dsr=0x%02x", dsr);
407 		if (!(dsr & DSR_nBUSY))
408 			printk("%cBusy", sep);
409 		if (dsr & DSR_nACK)
410 			printk("%cnAck", sep);
411 		if (dsr & DSR_PERROR)
412 			printk("%cPError", sep);
413 		if (dsr & DSR_SELECT)
414 			printk("%cSelect", sep);
415 		if (dsr & DSR_nFAULT)
416 			printk("%cnFault", sep);
417 		if (!(dsr & DSR_nPRINT))
418 			printk("%c(Print)", sep);
419 		if (dsr & DSR_TIMEOUT)
420 			printk("%cTimeout", sep);
421 		printk("\n");
422 	}
423 #undef sep
424 }
425 #else /* DEBUG_PARPORT_IP32 < 2 */
426 #define parport_ip32_dump_state(...)	do { } while (0)
427 #endif
428 
429 /*
430  * CHECK_EXTRA_BITS - track and log extra bits
431  * @p:		pointer to &struct parport
432  * @b:		byte to inspect
433  * @m:		bit mask of authorized bits
434  *
435  * This is used to track and log extra bits that should not be there in
436  * parport_ip32_write_control() and parport_ip32_frob_control().  It is only
437  * defined if %DEBUG_PARPORT_IP32 >= 1.
438  */
439 #if DEBUG_PARPORT_IP32 >= 1
440 #define CHECK_EXTRA_BITS(p, b, m)					\
441 	do {								\
442 		unsigned int __b = (b), __m = (m);			\
443 		if (__b & ~__m)						\
444 			pr_debug1(PPIP32 "%s: extra bits in %s(%s): "	\
445 				  "0x%02x/0x%02x\n",			\
446 				  (p)->name, __func__, #b, __b, __m);	\
447 	} while (0)
448 #else /* DEBUG_PARPORT_IP32 < 1 */
449 #define CHECK_EXTRA_BITS(...)	do { } while (0)
450 #endif
451 
452 /*--- IP32 parallel port DMA operations --------------------------------*/
453 
454 /**
455  * struct parport_ip32_dma_data - private data needed for DMA operation
456  * @dir:	DMA direction (from or to device)
457  * @buf:	buffer physical address
458  * @len:	buffer length
459  * @next:	address of next bytes to DMA transfer
460  * @left:	number of bytes remaining
461  * @ctx:	next context to write (0: context_a; 1: context_b)
462  * @irq_on:	are the DMA IRQs currently enabled?
463  * @lock:	spinlock to protect access to the structure
464  */
465 struct parport_ip32_dma_data {
466 	enum dma_data_direction		dir;
467 	dma_addr_t			buf;
468 	dma_addr_t			next;
469 	size_t				len;
470 	size_t				left;
471 	unsigned int			ctx;
472 	unsigned int			irq_on;
473 	spinlock_t			lock;
474 };
475 static struct parport_ip32_dma_data parport_ip32_dma;
476 
477 /**
478  * parport_ip32_dma_setup_context - setup next DMA context
479  * @limit:	maximum data size for the context
480  *
481  * The alignment constraints must be verified in caller function, and the
482  * parameter @limit must be set accordingly.
483  */
484 static void parport_ip32_dma_setup_context(unsigned int limit)
485 {
486 	unsigned long flags;
487 
488 	spin_lock_irqsave(&parport_ip32_dma.lock, flags);
489 	if (parport_ip32_dma.left > 0) {
490 		/* Note: ctxreg is "volatile" here only because
491 		 * mace->perif.ctrl.parport.context_a and context_b are
492 		 * "volatile".  */
493 		volatile u64 __iomem *ctxreg = (parport_ip32_dma.ctx == 0) ?
494 			&mace->perif.ctrl.parport.context_a :
495 			&mace->perif.ctrl.parport.context_b;
496 		u64 count;
497 		u64 ctxval;
498 		if (parport_ip32_dma.left <= limit) {
499 			count = parport_ip32_dma.left;
500 			ctxval = MACEPAR_CONTEXT_LASTFLAG;
501 		} else {
502 			count = limit;
503 			ctxval = 0;
504 		}
505 
506 		pr_trace(NULL,
507 			 "(%u): 0x%04x:0x%04x, %u -> %u%s",
508 			 limit,
509 			 (unsigned int)parport_ip32_dma.buf,
510 			 (unsigned int)parport_ip32_dma.next,
511 			 (unsigned int)count,
512 			 parport_ip32_dma.ctx, ctxval ? "*" : "");
513 
514 		ctxval |= parport_ip32_dma.next &
515 			MACEPAR_CONTEXT_BASEADDR_MASK;
516 		ctxval |= ((count - 1) << MACEPAR_CONTEXT_DATALEN_SHIFT) &
517 			MACEPAR_CONTEXT_DATALEN_MASK;
518 		writeq(ctxval, ctxreg);
519 		parport_ip32_dma.next += count;
520 		parport_ip32_dma.left -= count;
521 		parport_ip32_dma.ctx ^= 1U;
522 	}
523 	/* If there is nothing more to send, disable IRQs to avoid to
524 	 * face an IRQ storm which can lock the machine.  Disable them
525 	 * only once. */
526 	if (parport_ip32_dma.left == 0 && parport_ip32_dma.irq_on) {
527 		pr_debug(PPIP32 "IRQ off (ctx)\n");
528 		disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);
529 		disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);
530 		parport_ip32_dma.irq_on = 0;
531 	}
532 	spin_unlock_irqrestore(&parport_ip32_dma.lock, flags);
533 }
534 
535 /**
536  * parport_ip32_dma_interrupt - DMA interrupt handler
537  * @irq:	interrupt number
538  * @dev_id:	unused
539  */
540 static irqreturn_t parport_ip32_dma_interrupt(int irq, void *dev_id)
541 {
542 	if (parport_ip32_dma.left)
543 		pr_trace(NULL, "(%d): ctx=%d", irq, parport_ip32_dma.ctx);
544 	parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);
545 	return IRQ_HANDLED;
546 }
547 
548 #if DEBUG_PARPORT_IP32
549 static irqreturn_t parport_ip32_merr_interrupt(int irq, void *dev_id)
550 {
551 	pr_trace1(NULL, "(%d)", irq);
552 	return IRQ_HANDLED;
553 }
554 #endif
555 
556 /**
557  * parport_ip32_dma_start - begins a DMA transfer
558  * @p:		partport to work on
559  * @dir:	DMA direction: DMA_TO_DEVICE or DMA_FROM_DEVICE
560  * @addr:	pointer to data buffer
561  * @count:	buffer size
562  *
563  * Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be
564  * correctly balanced.
565  */
566 static int parport_ip32_dma_start(struct parport *p,
567 		enum dma_data_direction dir, void *addr, size_t count)
568 {
569 	unsigned int limit;
570 	u64 ctrl;
571 
572 	pr_trace(NULL, "(%d, %lu)", dir, (unsigned long)count);
573 
574 	/* FIXME - add support for DMA_FROM_DEVICE.  In this case, buffer must
575 	 * be 64 bytes aligned. */
576 	BUG_ON(dir != DMA_TO_DEVICE);
577 
578 	/* Reset DMA controller */
579 	ctrl = MACEPAR_CTLSTAT_RESET;
580 	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
581 
582 	/* DMA IRQs should normally be enabled */
583 	if (!parport_ip32_dma.irq_on) {
584 		WARN_ON(1);
585 		enable_irq(MACEISA_PAR_CTXA_IRQ);
586 		enable_irq(MACEISA_PAR_CTXB_IRQ);
587 		parport_ip32_dma.irq_on = 1;
588 	}
589 
590 	/* Prepare DMA pointers */
591 	parport_ip32_dma.dir = dir;
592 	parport_ip32_dma.buf = dma_map_single(&p->bus_dev, addr, count, dir);
593 	parport_ip32_dma.len = count;
594 	parport_ip32_dma.next = parport_ip32_dma.buf;
595 	parport_ip32_dma.left = parport_ip32_dma.len;
596 	parport_ip32_dma.ctx = 0;
597 
598 	/* Setup DMA direction and first two contexts */
599 	ctrl = (dir == DMA_TO_DEVICE) ? 0 : MACEPAR_CTLSTAT_DIRECTION;
600 	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
601 	/* Single transfer should not cross a 4K page boundary */
602 	limit = MACEPAR_CONTEXT_DATA_BOUND -
603 		(parport_ip32_dma.next & (MACEPAR_CONTEXT_DATA_BOUND - 1));
604 	parport_ip32_dma_setup_context(limit);
605 	parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);
606 
607 	/* Real start of DMA transfer */
608 	ctrl |= MACEPAR_CTLSTAT_ENABLE;
609 	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
610 
611 	return 0;
612 }
613 
614 /**
615  * parport_ip32_dma_stop - ends a running DMA transfer
616  * @p:		partport to work on
617  *
618  * Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be
619  * correctly balanced.
620  */
621 static void parport_ip32_dma_stop(struct parport *p)
622 {
623 	u64 ctx_a;
624 	u64 ctx_b;
625 	u64 ctrl;
626 	u64 diag;
627 	size_t res[2];	/* {[0] = res_a, [1] = res_b} */
628 
629 	pr_trace(NULL, "()");
630 
631 	/* Disable IRQs */
632 	spin_lock_irq(&parport_ip32_dma.lock);
633 	if (parport_ip32_dma.irq_on) {
634 		pr_debug(PPIP32 "IRQ off (stop)\n");
635 		disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);
636 		disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);
637 		parport_ip32_dma.irq_on = 0;
638 	}
639 	spin_unlock_irq(&parport_ip32_dma.lock);
640 	/* Force IRQ synchronization, even if the IRQs were disabled
641 	 * elsewhere. */
642 	synchronize_irq(MACEISA_PAR_CTXA_IRQ);
643 	synchronize_irq(MACEISA_PAR_CTXB_IRQ);
644 
645 	/* Stop DMA transfer */
646 	ctrl = readq(&mace->perif.ctrl.parport.cntlstat);
647 	ctrl &= ~MACEPAR_CTLSTAT_ENABLE;
648 	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
649 
650 	/* Adjust residue (parport_ip32_dma.left) */
651 	ctx_a = readq(&mace->perif.ctrl.parport.context_a);
652 	ctx_b = readq(&mace->perif.ctrl.parport.context_b);
653 	ctrl = readq(&mace->perif.ctrl.parport.cntlstat);
654 	diag = readq(&mace->perif.ctrl.parport.diagnostic);
655 	res[0] = (ctrl & MACEPAR_CTLSTAT_CTXA_VALID) ?
656 		1 + ((ctx_a & MACEPAR_CONTEXT_DATALEN_MASK) >>
657 		     MACEPAR_CONTEXT_DATALEN_SHIFT) :
658 		0;
659 	res[1] = (ctrl & MACEPAR_CTLSTAT_CTXB_VALID) ?
660 		1 + ((ctx_b & MACEPAR_CONTEXT_DATALEN_MASK) >>
661 		     MACEPAR_CONTEXT_DATALEN_SHIFT) :
662 		0;
663 	if (diag & MACEPAR_DIAG_DMACTIVE)
664 		res[(diag & MACEPAR_DIAG_CTXINUSE) != 0] =
665 			1 + ((diag & MACEPAR_DIAG_CTRMASK) >>
666 			     MACEPAR_DIAG_CTRSHIFT);
667 	parport_ip32_dma.left += res[0] + res[1];
668 
669 	/* Reset DMA controller, and re-enable IRQs */
670 	ctrl = MACEPAR_CTLSTAT_RESET;
671 	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
672 	pr_debug(PPIP32 "IRQ on (stop)\n");
673 	enable_irq(MACEISA_PAR_CTXA_IRQ);
674 	enable_irq(MACEISA_PAR_CTXB_IRQ);
675 	parport_ip32_dma.irq_on = 1;
676 
677 	dma_unmap_single(&p->bus_dev, parport_ip32_dma.buf,
678 			 parport_ip32_dma.len, parport_ip32_dma.dir);
679 }
680 
681 /**
682  * parport_ip32_dma_get_residue - get residue from last DMA transfer
683  *
684  * Returns the number of bytes remaining from last DMA transfer.
685  */
686 static inline size_t parport_ip32_dma_get_residue(void)
687 {
688 	return parport_ip32_dma.left;
689 }
690 
691 /**
692  * parport_ip32_dma_register - initialize DMA engine
693  *
694  * Returns zero for success.
695  */
696 static int parport_ip32_dma_register(void)
697 {
698 	int err;
699 
700 	spin_lock_init(&parport_ip32_dma.lock);
701 	parport_ip32_dma.irq_on = 1;
702 
703 	/* Reset DMA controller */
704 	writeq(MACEPAR_CTLSTAT_RESET, &mace->perif.ctrl.parport.cntlstat);
705 
706 	/* Request IRQs */
707 	err = request_irq(MACEISA_PAR_CTXA_IRQ, parport_ip32_dma_interrupt,
708 			  0, "parport_ip32", NULL);
709 	if (err)
710 		goto fail_a;
711 	err = request_irq(MACEISA_PAR_CTXB_IRQ, parport_ip32_dma_interrupt,
712 			  0, "parport_ip32", NULL);
713 	if (err)
714 		goto fail_b;
715 #if DEBUG_PARPORT_IP32
716 	/* FIXME - what is this IRQ for? */
717 	err = request_irq(MACEISA_PAR_MERR_IRQ, parport_ip32_merr_interrupt,
718 			  0, "parport_ip32", NULL);
719 	if (err)
720 		goto fail_merr;
721 #endif
722 	return 0;
723 
724 #if DEBUG_PARPORT_IP32
725 fail_merr:
726 	free_irq(MACEISA_PAR_CTXB_IRQ, NULL);
727 #endif
728 fail_b:
729 	free_irq(MACEISA_PAR_CTXA_IRQ, NULL);
730 fail_a:
731 	return err;
732 }
733 
734 /**
735  * parport_ip32_dma_unregister - release and free resources for DMA engine
736  */
737 static void parport_ip32_dma_unregister(void)
738 {
739 #if DEBUG_PARPORT_IP32
740 	free_irq(MACEISA_PAR_MERR_IRQ, NULL);
741 #endif
742 	free_irq(MACEISA_PAR_CTXB_IRQ, NULL);
743 	free_irq(MACEISA_PAR_CTXA_IRQ, NULL);
744 }
745 
746 /*--- Interrupt handlers and associates --------------------------------*/
747 
748 /**
749  * parport_ip32_wakeup - wakes up code waiting for an interrupt
750  * @p:		pointer to &struct parport
751  */
752 static inline void parport_ip32_wakeup(struct parport *p)
753 {
754 	struct parport_ip32_private * const priv = p->physport->private_data;
755 	complete(&priv->irq_complete);
756 }
757 
758 /**
759  * parport_ip32_interrupt - interrupt handler
760  * @irq:	interrupt number
761  * @dev_id:	pointer to &struct parport
762  *
763  * Caught interrupts are forwarded to the upper parport layer if IRQ_mode is
764  * %PARPORT_IP32_IRQ_FWD.
765  */
766 static irqreturn_t parport_ip32_interrupt(int irq, void *dev_id)
767 {
768 	struct parport * const p = dev_id;
769 	struct parport_ip32_private * const priv = p->physport->private_data;
770 	enum parport_ip32_irq_mode irq_mode = priv->irq_mode;
771 
772 	switch (irq_mode) {
773 	case PARPORT_IP32_IRQ_FWD:
774 		return parport_irq_handler(irq, dev_id);
775 
776 	case PARPORT_IP32_IRQ_HERE:
777 		parport_ip32_wakeup(p);
778 		break;
779 	}
780 
781 	return IRQ_HANDLED;
782 }
783 
784 /*--- Some utility function to manipulate ECR register -----------------*/
785 
786 /**
787  * parport_ip32_read_econtrol - read contents of the ECR register
788  * @p:		pointer to &struct parport
789  */
790 static inline unsigned int parport_ip32_read_econtrol(struct parport *p)
791 {
792 	struct parport_ip32_private * const priv = p->physport->private_data;
793 	return readb(priv->regs.ecr);
794 }
795 
796 /**
797  * parport_ip32_write_econtrol - write new contents to the ECR register
798  * @p:		pointer to &struct parport
799  * @c:		new value to write
800  */
801 static inline void parport_ip32_write_econtrol(struct parport *p,
802 					       unsigned int c)
803 {
804 	struct parport_ip32_private * const priv = p->physport->private_data;
805 	writeb(c, priv->regs.ecr);
806 }
807 
808 /**
809  * parport_ip32_frob_econtrol - change bits from the ECR register
810  * @p:		pointer to &struct parport
811  * @mask:	bit mask of bits to change
812  * @val:	new value for changed bits
813  *
814  * Read from the ECR, mask out the bits in @mask, exclusive-or with the bits
815  * in @val, and write the result to the ECR.
816  */
817 static inline void parport_ip32_frob_econtrol(struct parport *p,
818 					      unsigned int mask,
819 					      unsigned int val)
820 {
821 	unsigned int c;
822 	c = (parport_ip32_read_econtrol(p) & ~mask) ^ val;
823 	parport_ip32_write_econtrol(p, c);
824 }
825 
826 /**
827  * parport_ip32_set_mode - change mode of ECP port
828  * @p:		pointer to &struct parport
829  * @mode:	new mode to write in ECR
830  *
831  * ECR is reset in a sane state (interrupts and DMA disabled), and placed in
832  * mode @mode.  Go through PS2 mode if needed.
833  */
834 static void parport_ip32_set_mode(struct parport *p, unsigned int mode)
835 {
836 	unsigned int omode;
837 
838 	mode &= ECR_MODE_MASK;
839 	omode = parport_ip32_read_econtrol(p) & ECR_MODE_MASK;
840 
841 	if (!(mode == ECR_MODE_SPP || mode == ECR_MODE_PS2
842 	      || omode == ECR_MODE_SPP || omode == ECR_MODE_PS2)) {
843 		/* We have to go through PS2 mode */
844 		unsigned int ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
845 		parport_ip32_write_econtrol(p, ecr);
846 	}
847 	parport_ip32_write_econtrol(p, mode | ECR_nERRINTR | ECR_SERVINTR);
848 }
849 
850 /*--- Basic functions needed for parport -------------------------------*/
851 
852 /**
853  * parport_ip32_read_data - return current contents of the DATA register
854  * @p:		pointer to &struct parport
855  */
856 static inline unsigned char parport_ip32_read_data(struct parport *p)
857 {
858 	struct parport_ip32_private * const priv = p->physport->private_data;
859 	return readb(priv->regs.data);
860 }
861 
862 /**
863  * parport_ip32_write_data - set new contents for the DATA register
864  * @p:		pointer to &struct parport
865  * @d:		new value to write
866  */
867 static inline void parport_ip32_write_data(struct parport *p, unsigned char d)
868 {
869 	struct parport_ip32_private * const priv = p->physport->private_data;
870 	writeb(d, priv->regs.data);
871 }
872 
873 /**
874  * parport_ip32_read_status - return current contents of the DSR register
875  * @p:		pointer to &struct parport
876  */
877 static inline unsigned char parport_ip32_read_status(struct parport *p)
878 {
879 	struct parport_ip32_private * const priv = p->physport->private_data;
880 	return readb(priv->regs.dsr);
881 }
882 
883 /**
884  * __parport_ip32_read_control - return cached contents of the DCR register
885  * @p:		pointer to &struct parport
886  */
887 static inline unsigned int __parport_ip32_read_control(struct parport *p)
888 {
889 	struct parport_ip32_private * const priv = p->physport->private_data;
890 	return priv->dcr_cache; /* use soft copy */
891 }
892 
893 /**
894  * __parport_ip32_write_control - set new contents for the DCR register
895  * @p:		pointer to &struct parport
896  * @c:		new value to write
897  */
898 static inline void __parport_ip32_write_control(struct parport *p,
899 						unsigned int c)
900 {
901 	struct parport_ip32_private * const priv = p->physport->private_data;
902 	CHECK_EXTRA_BITS(p, c, priv->dcr_writable);
903 	c &= priv->dcr_writable; /* only writable bits */
904 	writeb(c, priv->regs.dcr);
905 	priv->dcr_cache = c;		/* update soft copy */
906 }
907 
908 /**
909  * __parport_ip32_frob_control - change bits from the DCR register
910  * @p:		pointer to &struct parport
911  * @mask:	bit mask of bits to change
912  * @val:	new value for changed bits
913  *
914  * This is equivalent to read from the DCR, mask out the bits in @mask,
915  * exclusive-or with the bits in @val, and write the result to the DCR.
916  * Actually, the cached contents of the DCR is used.
917  */
918 static inline void __parport_ip32_frob_control(struct parport *p,
919 					       unsigned int mask,
920 					       unsigned int val)
921 {
922 	unsigned int c;
923 	c = (__parport_ip32_read_control(p) & ~mask) ^ val;
924 	__parport_ip32_write_control(p, c);
925 }
926 
927 /**
928  * parport_ip32_read_control - return cached contents of the DCR register
929  * @p:		pointer to &struct parport
930  *
931  * The return value is masked so as to only return the value of %DCR_STROBE,
932  * %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
933  */
934 static inline unsigned char parport_ip32_read_control(struct parport *p)
935 {
936 	const unsigned int rm =
937 		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
938 	return __parport_ip32_read_control(p) & rm;
939 }
940 
941 /**
942  * parport_ip32_write_control - set new contents for the DCR register
943  * @p:		pointer to &struct parport
944  * @c:		new value to write
945  *
946  * The value is masked so as to only change the value of %DCR_STROBE,
947  * %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
948  */
949 static inline void parport_ip32_write_control(struct parport *p,
950 					      unsigned char c)
951 {
952 	const unsigned int wm =
953 		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
954 	CHECK_EXTRA_BITS(p, c, wm);
955 	__parport_ip32_frob_control(p, wm, c & wm);
956 }
957 
958 /**
959  * parport_ip32_frob_control - change bits from the DCR register
960  * @p:		pointer to &struct parport
961  * @mask:	bit mask of bits to change
962  * @val:	new value for changed bits
963  *
964  * This differs from __parport_ip32_frob_control() in that it only allows to
965  * change the value of %DCR_STROBE, %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
966  */
967 static inline unsigned char parport_ip32_frob_control(struct parport *p,
968 						      unsigned char mask,
969 						      unsigned char val)
970 {
971 	const unsigned int wm =
972 		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
973 	CHECK_EXTRA_BITS(p, mask, wm);
974 	CHECK_EXTRA_BITS(p, val, wm);
975 	__parport_ip32_frob_control(p, mask & wm, val & wm);
976 	return parport_ip32_read_control(p);
977 }
978 
979 /**
980  * parport_ip32_disable_irq - disable interrupts on the rising edge of nACK
981  * @p:		pointer to &struct parport
982  */
983 static inline void parport_ip32_disable_irq(struct parport *p)
984 {
985 	__parport_ip32_frob_control(p, DCR_IRQ, 0);
986 }
987 
988 /**
989  * parport_ip32_enable_irq - enable interrupts on the rising edge of nACK
990  * @p:		pointer to &struct parport
991  */
992 static inline void parport_ip32_enable_irq(struct parport *p)
993 {
994 	__parport_ip32_frob_control(p, DCR_IRQ, DCR_IRQ);
995 }
996 
997 /**
998  * parport_ip32_data_forward - enable host-to-peripheral communications
999  * @p:		pointer to &struct parport
1000  *
1001  * Enable the data line drivers, for 8-bit host-to-peripheral communications.
1002  */
1003 static inline void parport_ip32_data_forward(struct parport *p)
1004 {
1005 	__parport_ip32_frob_control(p, DCR_DIR, 0);
1006 }
1007 
1008 /**
1009  * parport_ip32_data_reverse - enable peripheral-to-host communications
1010  * @p:		pointer to &struct parport
1011  *
1012  * Place the data bus in a high impedance state, if @p->modes has the
1013  * PARPORT_MODE_TRISTATE bit set.
1014  */
1015 static inline void parport_ip32_data_reverse(struct parport *p)
1016 {
1017 	__parport_ip32_frob_control(p, DCR_DIR, DCR_DIR);
1018 }
1019 
1020 /**
1021  * parport_ip32_init_state - for core parport code
1022  * @dev:	pointer to &struct pardevice
1023  * @s:		pointer to &struct parport_state to initialize
1024  */
1025 static void parport_ip32_init_state(struct pardevice *dev,
1026 				    struct parport_state *s)
1027 {
1028 	s->u.ip32.dcr = DCR_SELECT | DCR_nINIT;
1029 	s->u.ip32.ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
1030 }
1031 
1032 /**
1033  * parport_ip32_save_state - for core parport code
1034  * @p:		pointer to &struct parport
1035  * @s:		pointer to &struct parport_state to save state to
1036  */
1037 static void parport_ip32_save_state(struct parport *p,
1038 				    struct parport_state *s)
1039 {
1040 	s->u.ip32.dcr = __parport_ip32_read_control(p);
1041 	s->u.ip32.ecr = parport_ip32_read_econtrol(p);
1042 }
1043 
1044 /**
1045  * parport_ip32_restore_state - for core parport code
1046  * @p:		pointer to &struct parport
1047  * @s:		pointer to &struct parport_state to restore state from
1048  */
1049 static void parport_ip32_restore_state(struct parport *p,
1050 				       struct parport_state *s)
1051 {
1052 	parport_ip32_set_mode(p, s->u.ip32.ecr & ECR_MODE_MASK);
1053 	parport_ip32_write_econtrol(p, s->u.ip32.ecr);
1054 	__parport_ip32_write_control(p, s->u.ip32.dcr);
1055 }
1056 
1057 /*--- EPP mode functions -----------------------------------------------*/
1058 
1059 /**
1060  * parport_ip32_clear_epp_timeout - clear Timeout bit in EPP mode
1061  * @p:		pointer to &struct parport
1062  *
1063  * Returns 1 if the Timeout bit is clear, and 0 otherwise.
1064  */
1065 static unsigned int parport_ip32_clear_epp_timeout(struct parport *p)
1066 {
1067 	struct parport_ip32_private * const priv = p->physport->private_data;
1068 	unsigned int cleared;
1069 
1070 	if (!(parport_ip32_read_status(p) & DSR_TIMEOUT))
1071 		cleared = 1;
1072 	else {
1073 		unsigned int r;
1074 		/* To clear timeout some chips require double read */
1075 		parport_ip32_read_status(p);
1076 		r = parport_ip32_read_status(p);
1077 		/* Some reset by writing 1 */
1078 		writeb(r | DSR_TIMEOUT, priv->regs.dsr);
1079 		/* Others by writing 0 */
1080 		writeb(r & ~DSR_TIMEOUT, priv->regs.dsr);
1081 
1082 		r = parport_ip32_read_status(p);
1083 		cleared = !(r & DSR_TIMEOUT);
1084 	}
1085 
1086 	pr_trace(p, "(): %s", cleared ? "cleared" : "failed");
1087 	return cleared;
1088 }
1089 
1090 /**
1091  * parport_ip32_epp_read - generic EPP read function
1092  * @eppreg:	I/O register to read from
1093  * @p:		pointer to &struct parport
1094  * @buf:	buffer to store read data
1095  * @len:	length of buffer @buf
1096  * @flags:	may be PARPORT_EPP_FAST
1097  */
1098 static size_t parport_ip32_epp_read(void __iomem *eppreg,
1099 				    struct parport *p, void *buf,
1100 				    size_t len, int flags)
1101 {
1102 	struct parport_ip32_private * const priv = p->physport->private_data;
1103 	size_t got;
1104 	parport_ip32_set_mode(p, ECR_MODE_EPP);
1105 	parport_ip32_data_reverse(p);
1106 	parport_ip32_write_control(p, DCR_nINIT);
1107 	if ((flags & PARPORT_EPP_FAST) && (len > 1)) {
1108 		readsb(eppreg, buf, len);
1109 		if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1110 			parport_ip32_clear_epp_timeout(p);
1111 			return -EIO;
1112 		}
1113 		got = len;
1114 	} else {
1115 		u8 *bufp = buf;
1116 		for (got = 0; got < len; got++) {
1117 			*bufp++ = readb(eppreg);
1118 			if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1119 				parport_ip32_clear_epp_timeout(p);
1120 				break;
1121 			}
1122 		}
1123 	}
1124 	parport_ip32_data_forward(p);
1125 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1126 	return got;
1127 }
1128 
1129 /**
1130  * parport_ip32_epp_write - generic EPP write function
1131  * @eppreg:	I/O register to write to
1132  * @p:		pointer to &struct parport
1133  * @buf:	buffer of data to write
1134  * @len:	length of buffer @buf
1135  * @flags:	may be PARPORT_EPP_FAST
1136  */
1137 static size_t parport_ip32_epp_write(void __iomem *eppreg,
1138 				     struct parport *p, const void *buf,
1139 				     size_t len, int flags)
1140 {
1141 	struct parport_ip32_private * const priv = p->physport->private_data;
1142 	size_t written;
1143 	parport_ip32_set_mode(p, ECR_MODE_EPP);
1144 	parport_ip32_data_forward(p);
1145 	parport_ip32_write_control(p, DCR_nINIT);
1146 	if ((flags & PARPORT_EPP_FAST) && (len > 1)) {
1147 		writesb(eppreg, buf, len);
1148 		if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1149 			parport_ip32_clear_epp_timeout(p);
1150 			return -EIO;
1151 		}
1152 		written = len;
1153 	} else {
1154 		const u8 *bufp = buf;
1155 		for (written = 0; written < len; written++) {
1156 			writeb(*bufp++, eppreg);
1157 			if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1158 				parport_ip32_clear_epp_timeout(p);
1159 				break;
1160 			}
1161 		}
1162 	}
1163 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1164 	return written;
1165 }
1166 
1167 /**
1168  * parport_ip32_epp_read_data - read a block of data in EPP mode
1169  * @p:		pointer to &struct parport
1170  * @buf:	buffer to store read data
1171  * @len:	length of buffer @buf
1172  * @flags:	may be PARPORT_EPP_FAST
1173  */
1174 static size_t parport_ip32_epp_read_data(struct parport *p, void *buf,
1175 					 size_t len, int flags)
1176 {
1177 	struct parport_ip32_private * const priv = p->physport->private_data;
1178 	return parport_ip32_epp_read(priv->regs.eppData0, p, buf, len, flags);
1179 }
1180 
1181 /**
1182  * parport_ip32_epp_write_data - write a block of data in EPP mode
1183  * @p:		pointer to &struct parport
1184  * @buf:	buffer of data to write
1185  * @len:	length of buffer @buf
1186  * @flags:	may be PARPORT_EPP_FAST
1187  */
1188 static size_t parport_ip32_epp_write_data(struct parport *p, const void *buf,
1189 					  size_t len, int flags)
1190 {
1191 	struct parport_ip32_private * const priv = p->physport->private_data;
1192 	return parport_ip32_epp_write(priv->regs.eppData0, p, buf, len, flags);
1193 }
1194 
1195 /**
1196  * parport_ip32_epp_read_addr - read a block of addresses in EPP mode
1197  * @p:		pointer to &struct parport
1198  * @buf:	buffer to store read data
1199  * @len:	length of buffer @buf
1200  * @flags:	may be PARPORT_EPP_FAST
1201  */
1202 static size_t parport_ip32_epp_read_addr(struct parport *p, void *buf,
1203 					 size_t len, int flags)
1204 {
1205 	struct parport_ip32_private * const priv = p->physport->private_data;
1206 	return parport_ip32_epp_read(priv->regs.eppAddr, p, buf, len, flags);
1207 }
1208 
1209 /**
1210  * parport_ip32_epp_write_addr - write a block of addresses in EPP mode
1211  * @p:		pointer to &struct parport
1212  * @buf:	buffer of data to write
1213  * @len:	length of buffer @buf
1214  * @flags:	may be PARPORT_EPP_FAST
1215  */
1216 static size_t parport_ip32_epp_write_addr(struct parport *p, const void *buf,
1217 					  size_t len, int flags)
1218 {
1219 	struct parport_ip32_private * const priv = p->physport->private_data;
1220 	return parport_ip32_epp_write(priv->regs.eppAddr, p, buf, len, flags);
1221 }
1222 
1223 /*--- ECP mode functions (FIFO) ----------------------------------------*/
1224 
1225 /**
1226  * parport_ip32_fifo_wait_break - check if the waiting function should return
1227  * @p:		pointer to &struct parport
1228  * @expire:	timeout expiring date, in jiffies
1229  *
1230  * parport_ip32_fifo_wait_break() checks if the waiting function should return
1231  * immediately or not.  The break conditions are:
1232  *	- expired timeout;
1233  *	- a pending signal;
1234  *	- nFault asserted low.
1235  * This function also calls cond_resched().
1236  */
1237 static unsigned int parport_ip32_fifo_wait_break(struct parport *p,
1238 						 unsigned long expire)
1239 {
1240 	cond_resched();
1241 	if (time_after(jiffies, expire)) {
1242 		pr_debug1(PPIP32 "%s: FIFO write timed out\n", p->name);
1243 		return 1;
1244 	}
1245 	if (signal_pending(current)) {
1246 		pr_debug1(PPIP32 "%s: Signal pending\n", p->name);
1247 		return 1;
1248 	}
1249 	if (!(parport_ip32_read_status(p) & DSR_nFAULT)) {
1250 		pr_debug1(PPIP32 "%s: nFault asserted low\n", p->name);
1251 		return 1;
1252 	}
1253 	return 0;
1254 }
1255 
1256 /**
1257  * parport_ip32_fwp_wait_polling - wait for FIFO to empty (polling)
1258  * @p:		pointer to &struct parport
1259  *
1260  * Returns the number of bytes that can safely be written in the FIFO.  A
1261  * return value of zero means that the calling function should terminate as
1262  * fast as possible.
1263  */
1264 static unsigned int parport_ip32_fwp_wait_polling(struct parport *p)
1265 {
1266 	struct parport_ip32_private * const priv = p->physport->private_data;
1267 	struct parport * const physport = p->physport;
1268 	unsigned long expire;
1269 	unsigned int count;
1270 	unsigned int ecr;
1271 
1272 	expire = jiffies + physport->cad->timeout;
1273 	count = 0;
1274 	while (1) {
1275 		if (parport_ip32_fifo_wait_break(p, expire))
1276 			break;
1277 
1278 		/* Check FIFO state.  We do nothing when the FIFO is nor full,
1279 		 * nor empty.  It appears that the FIFO full bit is not always
1280 		 * reliable, the FIFO state is sometimes wrongly reported, and
1281 		 * the chip gets confused if we give it another byte. */
1282 		ecr = parport_ip32_read_econtrol(p);
1283 		if (ecr & ECR_F_EMPTY) {
1284 			/* FIFO is empty, fill it up */
1285 			count = priv->fifo_depth;
1286 			break;
1287 		}
1288 
1289 		/* Wait a moment... */
1290 		udelay(FIFO_POLLING_INTERVAL);
1291 	} /* while (1) */
1292 
1293 	return count;
1294 }
1295 
1296 /**
1297  * parport_ip32_fwp_wait_interrupt - wait for FIFO to empty (interrupt-driven)
1298  * @p:		pointer to &struct parport
1299  *
1300  * Returns the number of bytes that can safely be written in the FIFO.  A
1301  * return value of zero means that the calling function should terminate as
1302  * fast as possible.
1303  */
1304 static unsigned int parport_ip32_fwp_wait_interrupt(struct parport *p)
1305 {
1306 	static unsigned int lost_interrupt = 0;
1307 	struct parport_ip32_private * const priv = p->physport->private_data;
1308 	struct parport * const physport = p->physport;
1309 	unsigned long nfault_timeout;
1310 	unsigned long expire;
1311 	unsigned int count;
1312 	unsigned int ecr;
1313 
1314 	nfault_timeout = min((unsigned long)physport->cad->timeout,
1315 			     msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));
1316 	expire = jiffies + physport->cad->timeout;
1317 	count = 0;
1318 	while (1) {
1319 		if (parport_ip32_fifo_wait_break(p, expire))
1320 			break;
1321 
1322 		/* Initialize mutex used to take interrupts into account */
1323 		reinit_completion(&priv->irq_complete);
1324 
1325 		/* Enable serviceIntr */
1326 		parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
1327 
1328 		/* Enabling serviceIntr while the FIFO is empty does not
1329 		 * always generate an interrupt, so check for emptiness
1330 		 * now. */
1331 		ecr = parport_ip32_read_econtrol(p);
1332 		if (!(ecr & ECR_F_EMPTY)) {
1333 			/* FIFO is not empty: wait for an interrupt or a
1334 			 * timeout to occur */
1335 			wait_for_completion_interruptible_timeout(
1336 				&priv->irq_complete, nfault_timeout);
1337 			ecr = parport_ip32_read_econtrol(p);
1338 			if ((ecr & ECR_F_EMPTY) && !(ecr & ECR_SERVINTR)
1339 			    && !lost_interrupt) {
1340 				printk(KERN_WARNING PPIP32
1341 				       "%s: lost interrupt in %s\n",
1342 				       p->name, __func__);
1343 				lost_interrupt = 1;
1344 			}
1345 		}
1346 
1347 		/* Disable serviceIntr */
1348 		parport_ip32_frob_econtrol(p, ECR_SERVINTR, ECR_SERVINTR);
1349 
1350 		/* Check FIFO state */
1351 		if (ecr & ECR_F_EMPTY) {
1352 			/* FIFO is empty, fill it up */
1353 			count = priv->fifo_depth;
1354 			break;
1355 		} else if (ecr & ECR_SERVINTR) {
1356 			/* FIFO is not empty, but we know that can safely push
1357 			 * writeIntrThreshold bytes into it */
1358 			count = priv->writeIntrThreshold;
1359 			break;
1360 		}
1361 		/* FIFO is not empty, and we did not get any interrupt.
1362 		 * Either it's time to check for nFault, or a signal is
1363 		 * pending.  This is verified in
1364 		 * parport_ip32_fifo_wait_break(), so we continue the loop. */
1365 	} /* while (1) */
1366 
1367 	return count;
1368 }
1369 
1370 /**
1371  * parport_ip32_fifo_write_block_pio - write a block of data (PIO mode)
1372  * @p:		pointer to &struct parport
1373  * @buf:	buffer of data to write
1374  * @len:	length of buffer @buf
1375  *
1376  * Uses PIO to write the contents of the buffer @buf into the parallel port
1377  * FIFO.  Returns the number of bytes that were actually written.  It can work
1378  * with or without the help of interrupts.  The parallel port must be
1379  * correctly initialized before calling parport_ip32_fifo_write_block_pio().
1380  */
1381 static size_t parport_ip32_fifo_write_block_pio(struct parport *p,
1382 						const void *buf, size_t len)
1383 {
1384 	struct parport_ip32_private * const priv = p->physport->private_data;
1385 	const u8 *bufp = buf;
1386 	size_t left = len;
1387 
1388 	priv->irq_mode = PARPORT_IP32_IRQ_HERE;
1389 
1390 	while (left > 0) {
1391 		unsigned int count;
1392 
1393 		count = (p->irq == PARPORT_IRQ_NONE) ?
1394 			parport_ip32_fwp_wait_polling(p) :
1395 			parport_ip32_fwp_wait_interrupt(p);
1396 		if (count == 0)
1397 			break;	/* Transmission should be stopped */
1398 		if (count > left)
1399 			count = left;
1400 		if (count == 1) {
1401 			writeb(*bufp, priv->regs.fifo);
1402 			bufp++, left--;
1403 		} else {
1404 			writesb(priv->regs.fifo, bufp, count);
1405 			bufp += count, left -= count;
1406 		}
1407 	}
1408 
1409 	priv->irq_mode = PARPORT_IP32_IRQ_FWD;
1410 
1411 	return len - left;
1412 }
1413 
1414 /**
1415  * parport_ip32_fifo_write_block_dma - write a block of data (DMA mode)
1416  * @p:		pointer to &struct parport
1417  * @buf:	buffer of data to write
1418  * @len:	length of buffer @buf
1419  *
1420  * Uses DMA to write the contents of the buffer @buf into the parallel port
1421  * FIFO.  Returns the number of bytes that were actually written.  The
1422  * parallel port must be correctly initialized before calling
1423  * parport_ip32_fifo_write_block_dma().
1424  */
1425 static size_t parport_ip32_fifo_write_block_dma(struct parport *p,
1426 						const void *buf, size_t len)
1427 {
1428 	struct parport_ip32_private * const priv = p->physport->private_data;
1429 	struct parport * const physport = p->physport;
1430 	unsigned long nfault_timeout;
1431 	unsigned long expire;
1432 	size_t written;
1433 	unsigned int ecr;
1434 
1435 	priv->irq_mode = PARPORT_IP32_IRQ_HERE;
1436 
1437 	parport_ip32_dma_start(p, DMA_TO_DEVICE, (void *)buf, len);
1438 	reinit_completion(&priv->irq_complete);
1439 	parport_ip32_frob_econtrol(p, ECR_DMAEN | ECR_SERVINTR, ECR_DMAEN);
1440 
1441 	nfault_timeout = min((unsigned long)physport->cad->timeout,
1442 			     msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));
1443 	expire = jiffies + physport->cad->timeout;
1444 	while (1) {
1445 		if (parport_ip32_fifo_wait_break(p, expire))
1446 			break;
1447 		wait_for_completion_interruptible_timeout(&priv->irq_complete,
1448 							  nfault_timeout);
1449 		ecr = parport_ip32_read_econtrol(p);
1450 		if (ecr & ECR_SERVINTR)
1451 			break;	/* DMA transfer just finished */
1452 	}
1453 	parport_ip32_dma_stop(p);
1454 	written = len - parport_ip32_dma_get_residue();
1455 
1456 	priv->irq_mode = PARPORT_IP32_IRQ_FWD;
1457 
1458 	return written;
1459 }
1460 
1461 /**
1462  * parport_ip32_fifo_write_block - write a block of data
1463  * @p:		pointer to &struct parport
1464  * @buf:	buffer of data to write
1465  * @len:	length of buffer @buf
1466  *
1467  * Uses PIO or DMA to write the contents of the buffer @buf into the parallel
1468  * p FIFO.  Returns the number of bytes that were actually written.
1469  */
1470 static size_t parport_ip32_fifo_write_block(struct parport *p,
1471 					    const void *buf, size_t len)
1472 {
1473 	size_t written = 0;
1474 	if (len)
1475 		/* FIXME - Maybe some threshold value should be set for @len
1476 		 * under which we revert to PIO mode? */
1477 		written = (p->modes & PARPORT_MODE_DMA) ?
1478 			parport_ip32_fifo_write_block_dma(p, buf, len) :
1479 			parport_ip32_fifo_write_block_pio(p, buf, len);
1480 	return written;
1481 }
1482 
1483 /**
1484  * parport_ip32_drain_fifo - wait for FIFO to empty
1485  * @p:		pointer to &struct parport
1486  * @timeout:	timeout, in jiffies
1487  *
1488  * This function waits for FIFO to empty.  It returns 1 when FIFO is empty, or
1489  * 0 if the timeout @timeout is reached before, or if a signal is pending.
1490  */
1491 static unsigned int parport_ip32_drain_fifo(struct parport *p,
1492 					    unsigned long timeout)
1493 {
1494 	unsigned long expire = jiffies + timeout;
1495 	unsigned int polling_interval;
1496 	unsigned int counter;
1497 
1498 	/* Busy wait for approx. 200us */
1499 	for (counter = 0; counter < 40; counter++) {
1500 		if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)
1501 			break;
1502 		if (time_after(jiffies, expire))
1503 			break;
1504 		if (signal_pending(current))
1505 			break;
1506 		udelay(5);
1507 	}
1508 	/* Poll slowly.  Polling interval starts with 1 millisecond, and is
1509 	 * increased exponentially until 128.  */
1510 	polling_interval = 1; /* msecs */
1511 	while (!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY)) {
1512 		if (time_after_eq(jiffies, expire))
1513 			break;
1514 		msleep_interruptible(polling_interval);
1515 		if (signal_pending(current))
1516 			break;
1517 		if (polling_interval < 128)
1518 			polling_interval *= 2;
1519 	}
1520 
1521 	return !!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY);
1522 }
1523 
1524 /**
1525  * parport_ip32_get_fifo_residue - reset FIFO
1526  * @p:		pointer to &struct parport
1527  * @mode:	current operation mode (ECR_MODE_PPF or ECR_MODE_ECP)
1528  *
1529  * This function resets FIFO, and returns the number of bytes remaining in it.
1530  */
1531 static unsigned int parport_ip32_get_fifo_residue(struct parport *p,
1532 						  unsigned int mode)
1533 {
1534 	struct parport_ip32_private * const priv = p->physport->private_data;
1535 	unsigned int residue;
1536 	unsigned int cnfga;
1537 
1538 	/* FIXME - We are missing one byte if the printer is off-line.  I
1539 	 * don't know how to detect this.  It looks that the full bit is not
1540 	 * always reliable.  For the moment, the problem is avoided in most
1541 	 * cases by testing for BUSY in parport_ip32_compat_write_data().
1542 	 */
1543 	if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)
1544 		residue = 0;
1545 	else {
1546 		pr_debug1(PPIP32 "%s: FIFO is stuck\n", p->name);
1547 
1548 		/* Stop all transfers.
1549 		 *
1550 		 * Microsoft's document instructs to drive DCR_STROBE to 0,
1551 		 * but it doesn't work (at least in Compatibility mode, not
1552 		 * tested in ECP mode).  Switching directly to Test mode (as
1553 		 * in parport_pc) is not an option: it does confuse the port,
1554 		 * ECP service interrupts are no more working after that.  A
1555 		 * hard reset is then needed to revert to a sane state.
1556 		 *
1557 		 * Let's hope that the FIFO is really stuck and that the
1558 		 * peripheral doesn't wake up now.
1559 		 */
1560 		parport_ip32_frob_control(p, DCR_STROBE, 0);
1561 
1562 		/* Fill up FIFO */
1563 		for (residue = priv->fifo_depth; residue > 0; residue--) {
1564 			if (parport_ip32_read_econtrol(p) & ECR_F_FULL)
1565 				break;
1566 			writeb(0x00, priv->regs.fifo);
1567 		}
1568 	}
1569 	if (residue)
1570 		pr_debug1(PPIP32 "%s: %d PWord%s left in FIFO\n",
1571 			  p->name, residue,
1572 			  (residue == 1) ? " was" : "s were");
1573 
1574 	/* Now reset the FIFO */
1575 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1576 
1577 	/* Host recovery for ECP mode */
1578 	if (mode == ECR_MODE_ECP) {
1579 		parport_ip32_data_reverse(p);
1580 		parport_ip32_frob_control(p, DCR_nINIT, 0);
1581 		if (parport_wait_peripheral(p, DSR_PERROR, 0))
1582 			pr_debug1(PPIP32 "%s: PEerror timeout 1 in %s\n",
1583 				  p->name, __func__);
1584 		parport_ip32_frob_control(p, DCR_STROBE, DCR_STROBE);
1585 		parport_ip32_frob_control(p, DCR_nINIT, DCR_nINIT);
1586 		if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR))
1587 			pr_debug1(PPIP32 "%s: PEerror timeout 2 in %s\n",
1588 				  p->name, __func__);
1589 	}
1590 
1591 	/* Adjust residue if needed */
1592 	parport_ip32_set_mode(p, ECR_MODE_CFG);
1593 	cnfga = readb(priv->regs.cnfgA);
1594 	if (!(cnfga & CNFGA_nBYTEINTRANS)) {
1595 		pr_debug1(PPIP32 "%s: cnfgA contains 0x%02x\n",
1596 			  p->name, cnfga);
1597 		pr_debug1(PPIP32 "%s: Accounting for extra byte\n",
1598 			  p->name);
1599 		residue++;
1600 	}
1601 
1602 	/* Don't care about partial PWords since we do not support
1603 	 * PWord != 1 byte. */
1604 
1605 	/* Back to forward PS2 mode. */
1606 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1607 	parport_ip32_data_forward(p);
1608 
1609 	return residue;
1610 }
1611 
1612 /**
1613  * parport_ip32_compat_write_data - write a block of data in SPP mode
1614  * @p:		pointer to &struct parport
1615  * @buf:	buffer of data to write
1616  * @len:	length of buffer @buf
1617  * @flags:	ignored
1618  */
1619 static size_t parport_ip32_compat_write_data(struct parport *p,
1620 					     const void *buf, size_t len,
1621 					     int flags)
1622 {
1623 	static unsigned int ready_before = 1;
1624 	struct parport_ip32_private * const priv = p->physport->private_data;
1625 	struct parport * const physport = p->physport;
1626 	size_t written = 0;
1627 
1628 	/* Special case: a timeout of zero means we cannot call schedule().
1629 	 * Also if O_NONBLOCK is set then use the default implementation. */
1630 	if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
1631 		return parport_ieee1284_write_compat(p, buf, len, flags);
1632 
1633 	/* Reset FIFO, go in forward mode, and disable ackIntEn */
1634 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1635 	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
1636 	parport_ip32_data_forward(p);
1637 	parport_ip32_disable_irq(p);
1638 	parport_ip32_set_mode(p, ECR_MODE_PPF);
1639 	physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
1640 
1641 	/* Wait for peripheral to become ready */
1642 	if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,
1643 				       DSR_nBUSY | DSR_nFAULT)) {
1644 		/* Avoid to flood the logs */
1645 		if (ready_before)
1646 			printk(KERN_INFO PPIP32 "%s: not ready in %s\n",
1647 			       p->name, __func__);
1648 		ready_before = 0;
1649 		goto stop;
1650 	}
1651 	ready_before = 1;
1652 
1653 	written = parport_ip32_fifo_write_block(p, buf, len);
1654 
1655 	/* Wait FIFO to empty.  Timeout is proportional to FIFO_depth.  */
1656 	parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);
1657 
1658 	/* Check for a potential residue */
1659 	written -= parport_ip32_get_fifo_residue(p, ECR_MODE_PPF);
1660 
1661 	/* Then, wait for BUSY to get low. */
1662 	if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))
1663 		printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",
1664 		       p->name, __func__);
1665 
1666 stop:
1667 	/* Reset FIFO */
1668 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1669 	physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
1670 
1671 	return written;
1672 }
1673 
1674 /*
1675  * FIXME - Insert here parport_ip32_ecp_read_data().
1676  */
1677 
1678 /**
1679  * parport_ip32_ecp_write_data - write a block of data in ECP mode
1680  * @p:		pointer to &struct parport
1681  * @buf:	buffer of data to write
1682  * @len:	length of buffer @buf
1683  * @flags:	ignored
1684  */
1685 static size_t parport_ip32_ecp_write_data(struct parport *p,
1686 					  const void *buf, size_t len,
1687 					  int flags)
1688 {
1689 	static unsigned int ready_before = 1;
1690 	struct parport_ip32_private * const priv = p->physport->private_data;
1691 	struct parport * const physport = p->physport;
1692 	size_t written = 0;
1693 
1694 	/* Special case: a timeout of zero means we cannot call schedule().
1695 	 * Also if O_NONBLOCK is set then use the default implementation. */
1696 	if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
1697 		return parport_ieee1284_ecp_write_data(p, buf, len, flags);
1698 
1699 	/* Negotiate to forward mode if necessary. */
1700 	if (physport->ieee1284.phase != IEEE1284_PH_FWD_IDLE) {
1701 		/* Event 47: Set nInit high. */
1702 		parport_ip32_frob_control(p, DCR_nINIT | DCR_AUTOFD,
1703 					     DCR_nINIT | DCR_AUTOFD);
1704 
1705 		/* Event 49: PError goes high. */
1706 		if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR)) {
1707 			printk(KERN_DEBUG PPIP32 "%s: PError timeout in %s",
1708 			       p->name, __func__);
1709 			physport->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
1710 			return 0;
1711 		}
1712 	}
1713 
1714 	/* Reset FIFO, go in forward mode, and disable ackIntEn */
1715 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1716 	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
1717 	parport_ip32_data_forward(p);
1718 	parport_ip32_disable_irq(p);
1719 	parport_ip32_set_mode(p, ECR_MODE_ECP);
1720 	physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
1721 
1722 	/* Wait for peripheral to become ready */
1723 	if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,
1724 				       DSR_nBUSY | DSR_nFAULT)) {
1725 		/* Avoid to flood the logs */
1726 		if (ready_before)
1727 			printk(KERN_INFO PPIP32 "%s: not ready in %s\n",
1728 			       p->name, __func__);
1729 		ready_before = 0;
1730 		goto stop;
1731 	}
1732 	ready_before = 1;
1733 
1734 	written = parport_ip32_fifo_write_block(p, buf, len);
1735 
1736 	/* Wait FIFO to empty.  Timeout is proportional to FIFO_depth.  */
1737 	parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);
1738 
1739 	/* Check for a potential residue */
1740 	written -= parport_ip32_get_fifo_residue(p, ECR_MODE_ECP);
1741 
1742 	/* Then, wait for BUSY to get low. */
1743 	if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))
1744 		printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",
1745 		       p->name, __func__);
1746 
1747 stop:
1748 	/* Reset FIFO */
1749 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1750 	physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
1751 
1752 	return written;
1753 }
1754 
1755 /*
1756  * FIXME - Insert here parport_ip32_ecp_write_addr().
1757  */
1758 
1759 /*--- Default parport operations ---------------------------------------*/
1760 
1761 static const struct parport_operations parport_ip32_ops __initconst = {
1762 	.write_data		= parport_ip32_write_data,
1763 	.read_data		= parport_ip32_read_data,
1764 
1765 	.write_control		= parport_ip32_write_control,
1766 	.read_control		= parport_ip32_read_control,
1767 	.frob_control		= parport_ip32_frob_control,
1768 
1769 	.read_status		= parport_ip32_read_status,
1770 
1771 	.enable_irq		= parport_ip32_enable_irq,
1772 	.disable_irq		= parport_ip32_disable_irq,
1773 
1774 	.data_forward		= parport_ip32_data_forward,
1775 	.data_reverse		= parport_ip32_data_reverse,
1776 
1777 	.init_state		= parport_ip32_init_state,
1778 	.save_state		= parport_ip32_save_state,
1779 	.restore_state		= parport_ip32_restore_state,
1780 
1781 	.epp_write_data		= parport_ieee1284_epp_write_data,
1782 	.epp_read_data		= parport_ieee1284_epp_read_data,
1783 	.epp_write_addr		= parport_ieee1284_epp_write_addr,
1784 	.epp_read_addr		= parport_ieee1284_epp_read_addr,
1785 
1786 	.ecp_write_data		= parport_ieee1284_ecp_write_data,
1787 	.ecp_read_data		= parport_ieee1284_ecp_read_data,
1788 	.ecp_write_addr		= parport_ieee1284_ecp_write_addr,
1789 
1790 	.compat_write_data	= parport_ieee1284_write_compat,
1791 	.nibble_read_data	= parport_ieee1284_read_nibble,
1792 	.byte_read_data		= parport_ieee1284_read_byte,
1793 
1794 	.owner			= THIS_MODULE,
1795 };
1796 
1797 /*--- Device detection -------------------------------------------------*/
1798 
1799 /**
1800  * parport_ip32_ecp_supported - check for an ECP port
1801  * @p:		pointer to the &parport structure
1802  *
1803  * Returns 1 if an ECP port is found, and 0 otherwise.  This function actually
1804  * checks if an Extended Control Register seems to be present.  On successful
1805  * return, the port is placed in SPP mode.
1806  */
1807 static __init unsigned int parport_ip32_ecp_supported(struct parport *p)
1808 {
1809 	struct parport_ip32_private * const priv = p->physport->private_data;
1810 	unsigned int ecr;
1811 
1812 	ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
1813 	writeb(ecr, priv->regs.ecr);
1814 	if (readb(priv->regs.ecr) != (ecr | ECR_F_EMPTY))
1815 		goto fail;
1816 
1817 	pr_probe(p, "Found working ECR register\n");
1818 	parport_ip32_set_mode(p, ECR_MODE_SPP);
1819 	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
1820 	return 1;
1821 
1822 fail:
1823 	pr_probe(p, "ECR register not found\n");
1824 	return 0;
1825 }
1826 
1827 /**
1828  * parport_ip32_fifo_supported - check for FIFO parameters
1829  * @p:		pointer to the &parport structure
1830  *
1831  * Check for FIFO parameters of an Extended Capabilities Port.  Returns 1 on
1832  * success, and 0 otherwise.  Adjust FIFO parameters in the parport structure.
1833  * On return, the port is placed in SPP mode.
1834  */
1835 static __init unsigned int parport_ip32_fifo_supported(struct parport *p)
1836 {
1837 	struct parport_ip32_private * const priv = p->physport->private_data;
1838 	unsigned int configa, configb;
1839 	unsigned int pword;
1840 	unsigned int i;
1841 
1842 	/* Configuration mode */
1843 	parport_ip32_set_mode(p, ECR_MODE_CFG);
1844 	configa = readb(priv->regs.cnfgA);
1845 	configb = readb(priv->regs.cnfgB);
1846 
1847 	/* Find out PWord size */
1848 	switch (configa & CNFGA_ID_MASK) {
1849 	case CNFGA_ID_8:
1850 		pword = 1;
1851 		break;
1852 	case CNFGA_ID_16:
1853 		pword = 2;
1854 		break;
1855 	case CNFGA_ID_32:
1856 		pword = 4;
1857 		break;
1858 	default:
1859 		pr_probe(p, "Unknown implementation ID: 0x%0x\n",
1860 			 (configa & CNFGA_ID_MASK) >> CNFGA_ID_SHIFT);
1861 		goto fail;
1862 		break;
1863 	}
1864 	if (pword != 1) {
1865 		pr_probe(p, "Unsupported PWord size: %u\n", pword);
1866 		goto fail;
1867 	}
1868 	priv->pword = pword;
1869 	pr_probe(p, "PWord is %u bits\n", 8 * priv->pword);
1870 
1871 	/* Check for compression support */
1872 	writeb(configb | CNFGB_COMPRESS, priv->regs.cnfgB);
1873 	if (readb(priv->regs.cnfgB) & CNFGB_COMPRESS)
1874 		pr_probe(p, "Hardware compression detected (unsupported)\n");
1875 	writeb(configb & ~CNFGB_COMPRESS, priv->regs.cnfgB);
1876 
1877 	/* Reset FIFO and go in test mode (no interrupt, no DMA) */
1878 	parport_ip32_set_mode(p, ECR_MODE_TST);
1879 
1880 	/* FIFO must be empty now */
1881 	if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {
1882 		pr_probe(p, "FIFO not reset\n");
1883 		goto fail;
1884 	}
1885 
1886 	/* Find out FIFO depth. */
1887 	priv->fifo_depth = 0;
1888 	for (i = 0; i < 1024; i++) {
1889 		if (readb(priv->regs.ecr) & ECR_F_FULL) {
1890 			/* FIFO full */
1891 			priv->fifo_depth = i;
1892 			break;
1893 		}
1894 		writeb((u8)i, priv->regs.fifo);
1895 	}
1896 	if (i >= 1024) {
1897 		pr_probe(p, "Can't fill FIFO\n");
1898 		goto fail;
1899 	}
1900 	if (!priv->fifo_depth) {
1901 		pr_probe(p, "Can't get FIFO depth\n");
1902 		goto fail;
1903 	}
1904 	pr_probe(p, "FIFO is %u PWords deep\n", priv->fifo_depth);
1905 
1906 	/* Enable interrupts */
1907 	parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
1908 
1909 	/* Find out writeIntrThreshold: number of PWords we know we can write
1910 	 * if we get an interrupt. */
1911 	priv->writeIntrThreshold = 0;
1912 	for (i = 0; i < priv->fifo_depth; i++) {
1913 		if (readb(priv->regs.fifo) != (u8)i) {
1914 			pr_probe(p, "Invalid data in FIFO\n");
1915 			goto fail;
1916 		}
1917 		if (!priv->writeIntrThreshold
1918 		    && readb(priv->regs.ecr) & ECR_SERVINTR)
1919 			/* writeIntrThreshold reached */
1920 			priv->writeIntrThreshold = i + 1;
1921 		if (i + 1 < priv->fifo_depth
1922 		    && readb(priv->regs.ecr) & ECR_F_EMPTY) {
1923 			/* FIFO empty before the last byte? */
1924 			pr_probe(p, "Data lost in FIFO\n");
1925 			goto fail;
1926 		}
1927 	}
1928 	if (!priv->writeIntrThreshold) {
1929 		pr_probe(p, "Can't get writeIntrThreshold\n");
1930 		goto fail;
1931 	}
1932 	pr_probe(p, "writeIntrThreshold is %u\n", priv->writeIntrThreshold);
1933 
1934 	/* FIFO must be empty now */
1935 	if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {
1936 		pr_probe(p, "Can't empty FIFO\n");
1937 		goto fail;
1938 	}
1939 
1940 	/* Reset FIFO */
1941 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1942 	/* Set reverse direction (must be in PS2 mode) */
1943 	parport_ip32_data_reverse(p);
1944 	/* Test FIFO, no interrupt, no DMA */
1945 	parport_ip32_set_mode(p, ECR_MODE_TST);
1946 	/* Enable interrupts */
1947 	parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
1948 
1949 	/* Find out readIntrThreshold: number of PWords we can read if we get
1950 	 * an interrupt. */
1951 	priv->readIntrThreshold = 0;
1952 	for (i = 0; i < priv->fifo_depth; i++) {
1953 		writeb(0xaa, priv->regs.fifo);
1954 		if (readb(priv->regs.ecr) & ECR_SERVINTR) {
1955 			/* readIntrThreshold reached */
1956 			priv->readIntrThreshold = i + 1;
1957 			break;
1958 		}
1959 	}
1960 	if (!priv->readIntrThreshold) {
1961 		pr_probe(p, "Can't get readIntrThreshold\n");
1962 		goto fail;
1963 	}
1964 	pr_probe(p, "readIntrThreshold is %u\n", priv->readIntrThreshold);
1965 
1966 	/* Reset ECR */
1967 	parport_ip32_set_mode(p, ECR_MODE_PS2);
1968 	parport_ip32_data_forward(p);
1969 	parport_ip32_set_mode(p, ECR_MODE_SPP);
1970 	return 1;
1971 
1972 fail:
1973 	priv->fifo_depth = 0;
1974 	parport_ip32_set_mode(p, ECR_MODE_SPP);
1975 	return 0;
1976 }
1977 
1978 /*--- Initialization code ----------------------------------------------*/
1979 
1980 /**
1981  * parport_ip32_make_isa_registers - compute (ISA) register addresses
1982  * @regs:	pointer to &struct parport_ip32_regs to fill
1983  * @base:	base address of standard and EPP registers
1984  * @base_hi:	base address of ECP registers
1985  * @regshift:	how much to shift register offset by
1986  *
1987  * Compute register addresses, according to the ISA standard.  The addresses
1988  * of the standard and EPP registers are computed from address @base.  The
1989  * addresses of the ECP registers are computed from address @base_hi.
1990  */
1991 static void __init
1992 parport_ip32_make_isa_registers(struct parport_ip32_regs *regs,
1993 				void __iomem *base, void __iomem *base_hi,
1994 				unsigned int regshift)
1995 {
1996 #define r_base(offset)    ((u8 __iomem *)base    + ((offset) << regshift))
1997 #define r_base_hi(offset) ((u8 __iomem *)base_hi + ((offset) << regshift))
1998 	*regs = (struct parport_ip32_regs){
1999 		.data		= r_base(0),
2000 		.dsr		= r_base(1),
2001 		.dcr		= r_base(2),
2002 		.eppAddr	= r_base(3),
2003 		.eppData0	= r_base(4),
2004 		.eppData1	= r_base(5),
2005 		.eppData2	= r_base(6),
2006 		.eppData3	= r_base(7),
2007 		.ecpAFifo	= r_base(0),
2008 		.fifo		= r_base_hi(0),
2009 		.cnfgA		= r_base_hi(0),
2010 		.cnfgB		= r_base_hi(1),
2011 		.ecr		= r_base_hi(2)
2012 	};
2013 #undef r_base_hi
2014 #undef r_base
2015 }
2016 
2017 /**
2018  * parport_ip32_probe_port - probe and register IP32 built-in parallel port
2019  *
2020  * Returns the new allocated &parport structure.  On error, an error code is
2021  * encoded in return value with the ERR_PTR function.
2022  */
2023 static __init struct parport *parport_ip32_probe_port(void)
2024 {
2025 	struct parport_ip32_regs regs;
2026 	struct parport_ip32_private *priv = NULL;
2027 	struct parport_operations *ops = NULL;
2028 	struct parport *p = NULL;
2029 	int err;
2030 
2031 	parport_ip32_make_isa_registers(&regs, &mace->isa.parallel,
2032 					&mace->isa.ecp1284, 8 /* regshift */);
2033 
2034 	ops = kmalloc(sizeof(struct parport_operations), GFP_KERNEL);
2035 	priv = kmalloc(sizeof(struct parport_ip32_private), GFP_KERNEL);
2036 	p = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, ops);
2037 	if (ops == NULL || priv == NULL || p == NULL) {
2038 		err = -ENOMEM;
2039 		goto fail;
2040 	}
2041 	p->base = MACE_BASE + offsetof(struct sgi_mace, isa.parallel);
2042 	p->base_hi = MACE_BASE + offsetof(struct sgi_mace, isa.ecp1284);
2043 	p->private_data = priv;
2044 
2045 	*ops = parport_ip32_ops;
2046 	*priv = (struct parport_ip32_private){
2047 		.regs			= regs,
2048 		.dcr_writable		= DCR_DIR | DCR_SELECT | DCR_nINIT |
2049 					  DCR_AUTOFD | DCR_STROBE,
2050 		.irq_mode		= PARPORT_IP32_IRQ_FWD,
2051 	};
2052 	init_completion(&priv->irq_complete);
2053 
2054 	/* Probe port. */
2055 	if (!parport_ip32_ecp_supported(p)) {
2056 		err = -ENODEV;
2057 		goto fail;
2058 	}
2059 	parport_ip32_dump_state(p, "begin init", 0);
2060 
2061 	/* We found what looks like a working ECR register.  Simply assume
2062 	 * that all modes are correctly supported.  Enable basic modes. */
2063 	p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;
2064 	p->modes |= PARPORT_MODE_TRISTATE;
2065 
2066 	if (!parport_ip32_fifo_supported(p)) {
2067 		printk(KERN_WARNING PPIP32
2068 		       "%s: error: FIFO disabled\n", p->name);
2069 		/* Disable hardware modes depending on a working FIFO. */
2070 		features &= ~PARPORT_IP32_ENABLE_SPP;
2071 		features &= ~PARPORT_IP32_ENABLE_ECP;
2072 		/* DMA is not needed if FIFO is not supported.  */
2073 		features &= ~PARPORT_IP32_ENABLE_DMA;
2074 	}
2075 
2076 	/* Request IRQ */
2077 	if (features & PARPORT_IP32_ENABLE_IRQ) {
2078 		int irq = MACEISA_PARALLEL_IRQ;
2079 		if (request_irq(irq, parport_ip32_interrupt, 0, p->name, p)) {
2080 			printk(KERN_WARNING PPIP32
2081 			       "%s: error: IRQ disabled\n", p->name);
2082 			/* DMA cannot work without interrupts. */
2083 			features &= ~PARPORT_IP32_ENABLE_DMA;
2084 		} else {
2085 			pr_probe(p, "Interrupt support enabled\n");
2086 			p->irq = irq;
2087 			priv->dcr_writable |= DCR_IRQ;
2088 		}
2089 	}
2090 
2091 	/* Allocate DMA resources */
2092 	if (features & PARPORT_IP32_ENABLE_DMA) {
2093 		if (parport_ip32_dma_register())
2094 			printk(KERN_WARNING PPIP32
2095 			       "%s: error: DMA disabled\n", p->name);
2096 		else {
2097 			pr_probe(p, "DMA support enabled\n");
2098 			p->dma = 0; /* arbitrary value != PARPORT_DMA_NONE */
2099 			p->modes |= PARPORT_MODE_DMA;
2100 		}
2101 	}
2102 
2103 	if (features & PARPORT_IP32_ENABLE_SPP) {
2104 		/* Enable compatibility FIFO mode */
2105 		p->ops->compat_write_data = parport_ip32_compat_write_data;
2106 		p->modes |= PARPORT_MODE_COMPAT;
2107 		pr_probe(p, "Hardware support for SPP mode enabled\n");
2108 	}
2109 	if (features & PARPORT_IP32_ENABLE_EPP) {
2110 		/* Set up access functions to use EPP hardware. */
2111 		p->ops->epp_read_data = parport_ip32_epp_read_data;
2112 		p->ops->epp_write_data = parport_ip32_epp_write_data;
2113 		p->ops->epp_read_addr = parport_ip32_epp_read_addr;
2114 		p->ops->epp_write_addr = parport_ip32_epp_write_addr;
2115 		p->modes |= PARPORT_MODE_EPP;
2116 		pr_probe(p, "Hardware support for EPP mode enabled\n");
2117 	}
2118 	if (features & PARPORT_IP32_ENABLE_ECP) {
2119 		/* Enable ECP FIFO mode */
2120 		p->ops->ecp_write_data = parport_ip32_ecp_write_data;
2121 		/* FIXME - not implemented */
2122 /*		p->ops->ecp_read_data  = parport_ip32_ecp_read_data; */
2123 /*		p->ops->ecp_write_addr = parport_ip32_ecp_write_addr; */
2124 		p->modes |= PARPORT_MODE_ECP;
2125 		pr_probe(p, "Hardware support for ECP mode enabled\n");
2126 	}
2127 
2128 	/* Initialize the port with sensible values */
2129 	parport_ip32_set_mode(p, ECR_MODE_PS2);
2130 	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
2131 	parport_ip32_data_forward(p);
2132 	parport_ip32_disable_irq(p);
2133 	parport_ip32_write_data(p, 0x00);
2134 	parport_ip32_dump_state(p, "end init", 0);
2135 
2136 	/* Print out what we found */
2137 	printk(KERN_INFO "%s: SGI IP32 at 0x%lx (0x%lx)",
2138 	       p->name, p->base, p->base_hi);
2139 	if (p->irq != PARPORT_IRQ_NONE)
2140 		printk(", irq %d", p->irq);
2141 	printk(" [");
2142 #define printmode(x)	if (p->modes & PARPORT_MODE_##x)		\
2143 				printk("%s%s", f++ ? "," : "", #x)
2144 	{
2145 		unsigned int f = 0;
2146 		printmode(PCSPP);
2147 		printmode(TRISTATE);
2148 		printmode(COMPAT);
2149 		printmode(EPP);
2150 		printmode(ECP);
2151 		printmode(DMA);
2152 	}
2153 #undef printmode
2154 	printk("]\n");
2155 
2156 	parport_announce_port(p);
2157 	return p;
2158 
2159 fail:
2160 	if (p)
2161 		parport_put_port(p);
2162 	kfree(priv);
2163 	kfree(ops);
2164 	return ERR_PTR(err);
2165 }
2166 
2167 /**
2168  * parport_ip32_unregister_port - unregister a parallel port
2169  * @p:		pointer to the &struct parport
2170  *
2171  * Unregisters a parallel port and free previously allocated resources
2172  * (memory, IRQ, ...).
2173  */
2174 static __exit void parport_ip32_unregister_port(struct parport *p)
2175 {
2176 	struct parport_ip32_private * const priv = p->physport->private_data;
2177 	struct parport_operations *ops = p->ops;
2178 
2179 	parport_remove_port(p);
2180 	if (p->modes & PARPORT_MODE_DMA)
2181 		parport_ip32_dma_unregister();
2182 	if (p->irq != PARPORT_IRQ_NONE)
2183 		free_irq(p->irq, p);
2184 	parport_put_port(p);
2185 	kfree(priv);
2186 	kfree(ops);
2187 }
2188 
2189 /**
2190  * parport_ip32_init - module initialization function
2191  */
2192 static int __init parport_ip32_init(void)
2193 {
2194 	pr_info(PPIP32 "SGI IP32 built-in parallel port driver v0.6\n");
2195 	this_port = parport_ip32_probe_port();
2196 	return PTR_ERR_OR_ZERO(this_port);
2197 }
2198 
2199 /**
2200  * parport_ip32_exit - module termination function
2201  */
2202 static void __exit parport_ip32_exit(void)
2203 {
2204 	parport_ip32_unregister_port(this_port);
2205 }
2206 
2207 /*--- Module stuff -----------------------------------------------------*/
2208 
2209 MODULE_AUTHOR("Arnaud Giersch <arnaud.giersch@free.fr>");
2210 MODULE_DESCRIPTION("SGI IP32 built-in parallel port driver");
2211 MODULE_LICENSE("GPL");
2212 MODULE_VERSION("0.6");		/* update in parport_ip32_init() too */
2213 
2214 module_init(parport_ip32_init);
2215 module_exit(parport_ip32_exit);
2216 
2217 module_param(verbose_probing, bool, S_IRUGO);
2218 MODULE_PARM_DESC(verbose_probing, "Log chit-chat during initialization");
2219 
2220 module_param(features, uint, S_IRUGO);
2221 MODULE_PARM_DESC(features,
2222 		 "Bit mask of features to enable"
2223 		 ", bit 0: IRQ support"
2224 		 ", bit 1: DMA support"
2225 		 ", bit 2: hardware SPP mode"
2226 		 ", bit 3: hardware EPP mode"
2227 		 ", bit 4: hardware ECP mode");
2228 
2229 /*--- Inform (X)Emacs about preferred coding style ---------------------*/
2230 /*
2231  * Local Variables:
2232  * mode: c
2233  * c-file-style: "linux"
2234  * indent-tabs-mode: t
2235  * tab-width: 8
2236  * fill-column: 78
2237  * ispell-local-dictionary: "american"
2238  * End:
2239  */
2240