xref: /openbmc/linux/drivers/parisc/ccio-dma.c (revision ae213c44)
1 /*
2 ** ccio-dma.c:
3 **	DMA management routines for first generation cache-coherent machines.
4 **	Program U2/Uturn in "Virtual Mode" and use the I/O MMU.
5 **
6 **	(c) Copyright 2000 Grant Grundler
7 **	(c) Copyright 2000 Ryan Bradetich
8 **	(c) Copyright 2000 Hewlett-Packard Company
9 **
10 ** This program is free software; you can redistribute it and/or modify
11 ** it under the terms of the GNU General Public License as published by
12 ** the Free Software Foundation; either version 2 of the License, or
13 ** (at your option) any later version.
14 **
15 **
16 **  "Real Mode" operation refers to U2/Uturn chip operation.
17 **  U2/Uturn were designed to perform coherency checks w/o using
18 **  the I/O MMU - basically what x86 does.
19 **
20 **  Philipp Rumpf has a "Real Mode" driver for PCX-W machines at:
21 **      CVSROOT=:pserver:anonymous@198.186.203.37:/cvsroot/linux-parisc
22 **      cvs -z3 co linux/arch/parisc/kernel/dma-rm.c
23 **
24 **  I've rewritten his code to work under TPG's tree. See ccio-rm-dma.c.
25 **
26 **  Drawbacks of using Real Mode are:
27 **	o outbound DMA is slower - U2 won't prefetch data (GSC+ XQL signal).
28 **      o Inbound DMA less efficient - U2 can't use DMA_FAST attribute.
29 **	o Ability to do scatter/gather in HW is lost.
30 **	o Doesn't work under PCX-U/U+ machines since they didn't follow
31 **        the coherency design originally worked out. Only PCX-W does.
32 */
33 
34 #include <linux/types.h>
35 #include <linux/kernel.h>
36 #include <linux/init.h>
37 #include <linux/mm.h>
38 #include <linux/spinlock.h>
39 #include <linux/slab.h>
40 #include <linux/string.h>
41 #include <linux/pci.h>
42 #include <linux/reboot.h>
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #include <linux/scatterlist.h>
46 #include <linux/iommu-helper.h>
47 #include <linux/export.h>
48 
49 #include <asm/byteorder.h>
50 #include <asm/cache.h>		/* for L1_CACHE_BYTES */
51 #include <linux/uaccess.h>
52 #include <asm/page.h>
53 #include <asm/dma.h>
54 #include <asm/io.h>
55 #include <asm/hardware.h>       /* for register_module() */
56 #include <asm/parisc-device.h>
57 
58 #include "iommu.h"
59 
60 /*
61 ** Choose "ccio" since that's what HP-UX calls it.
62 ** Make it easier for folks to migrate from one to the other :^)
63 */
64 #define MODULE_NAME "ccio"
65 
66 #undef DEBUG_CCIO_RES
67 #undef DEBUG_CCIO_RUN
68 #undef DEBUG_CCIO_INIT
69 #undef DEBUG_CCIO_RUN_SG
70 
71 #ifdef CONFIG_PROC_FS
72 /* depends on proc fs support. But costs CPU performance. */
73 #undef CCIO_COLLECT_STATS
74 #endif
75 
76 #include <asm/runway.h>		/* for proc_runway_root */
77 
78 #ifdef DEBUG_CCIO_INIT
79 #define DBG_INIT(x...)  printk(x)
80 #else
81 #define DBG_INIT(x...)
82 #endif
83 
84 #ifdef DEBUG_CCIO_RUN
85 #define DBG_RUN(x...)   printk(x)
86 #else
87 #define DBG_RUN(x...)
88 #endif
89 
90 #ifdef DEBUG_CCIO_RES
91 #define DBG_RES(x...)   printk(x)
92 #else
93 #define DBG_RES(x...)
94 #endif
95 
96 #ifdef DEBUG_CCIO_RUN_SG
97 #define DBG_RUN_SG(x...) printk(x)
98 #else
99 #define DBG_RUN_SG(x...)
100 #endif
101 
102 #define CCIO_INLINE	inline
103 #define WRITE_U32(value, addr) __raw_writel(value, addr)
104 #define READ_U32(addr) __raw_readl(addr)
105 
106 #define U2_IOA_RUNWAY 0x580
107 #define U2_BC_GSC     0x501
108 #define UTURN_IOA_RUNWAY 0x581
109 #define UTURN_BC_GSC     0x502
110 
111 #define IOA_NORMAL_MODE      0x00020080 /* IO_CONTROL to turn on CCIO        */
112 #define CMD_TLB_DIRECT_WRITE 35         /* IO_COMMAND for I/O TLB Writes     */
113 #define CMD_TLB_PURGE        33         /* IO_COMMAND to Purge I/O TLB entry */
114 
115 struct ioa_registers {
116         /* Runway Supervisory Set */
117         int32_t    unused1[12];
118         uint32_t   io_command;             /* Offset 12 */
119         uint32_t   io_status;              /* Offset 13 */
120         uint32_t   io_control;             /* Offset 14 */
121         int32_t    unused2[1];
122 
123         /* Runway Auxiliary Register Set */
124         uint32_t   io_err_resp;            /* Offset  0 */
125         uint32_t   io_err_info;            /* Offset  1 */
126         uint32_t   io_err_req;             /* Offset  2 */
127         uint32_t   io_err_resp_hi;         /* Offset  3 */
128         uint32_t   io_tlb_entry_m;         /* Offset  4 */
129         uint32_t   io_tlb_entry_l;         /* Offset  5 */
130         uint32_t   unused3[1];
131         uint32_t   io_pdir_base;           /* Offset  7 */
132         uint32_t   io_io_low_hv;           /* Offset  8 */
133         uint32_t   io_io_high_hv;          /* Offset  9 */
134         uint32_t   unused4[1];
135         uint32_t   io_chain_id_mask;       /* Offset 11 */
136         uint32_t   unused5[2];
137         uint32_t   io_io_low;              /* Offset 14 */
138         uint32_t   io_io_high;             /* Offset 15 */
139 };
140 
141 /*
142 ** IOA Registers
143 ** -------------
144 **
145 ** Runway IO_CONTROL Register (+0x38)
146 **
147 ** The Runway IO_CONTROL register controls the forwarding of transactions.
148 **
149 ** | 0  ...  13  |  14 15 | 16 ... 21 | 22 | 23 24 |  25 ... 31 |
150 ** |    HV       |   TLB  |  reserved | HV | mode  |  reserved  |
151 **
152 ** o mode field indicates the address translation of transactions
153 **   forwarded from Runway to GSC+:
154 **       Mode Name     Value        Definition
155 **       Off (default)   0          Opaque to matching addresses.
156 **       Include         1          Transparent for matching addresses.
157 **       Peek            3          Map matching addresses.
158 **
159 **       + "Off" mode: Runway transactions which match the I/O range
160 **         specified by the IO_IO_LOW/IO_IO_HIGH registers will be ignored.
161 **       + "Include" mode: all addresses within the I/O range specified
162 **         by the IO_IO_LOW and IO_IO_HIGH registers are transparently
163 **         forwarded. This is the I/O Adapter's normal operating mode.
164 **       + "Peek" mode: used during system configuration to initialize the
165 **         GSC+ bus. Runway Write_Shorts in the address range specified by
166 **         IO_IO_LOW and IO_IO_HIGH are forwarded through the I/O Adapter
167 **         *AND* the GSC+ address is remapped to the Broadcast Physical
168 **         Address space by setting the 14 high order address bits of the
169 **         32 bit GSC+ address to ones.
170 **
171 ** o TLB field affects transactions which are forwarded from GSC+ to Runway.
172 **   "Real" mode is the poweron default.
173 **
174 **   TLB Mode  Value  Description
175 **   Real        0    No TLB translation. Address is directly mapped and the
176 **                    virtual address is composed of selected physical bits.
177 **   Error       1    Software fills the TLB manually.
178 **   Normal      2    IOA fetches IO TLB misses from IO PDIR (in host memory).
179 **
180 **
181 ** IO_IO_LOW_HV	  +0x60 (HV dependent)
182 ** IO_IO_HIGH_HV  +0x64 (HV dependent)
183 ** IO_IO_LOW      +0x78	(Architected register)
184 ** IO_IO_HIGH     +0x7c	(Architected register)
185 **
186 ** IO_IO_LOW and IO_IO_HIGH set the lower and upper bounds of the
187 ** I/O Adapter address space, respectively.
188 **
189 ** 0  ... 7 | 8 ... 15 |  16   ...   31 |
190 ** 11111111 | 11111111 |      address   |
191 **
192 ** Each LOW/HIGH pair describes a disjoint address space region.
193 ** (2 per GSC+ port). Each incoming Runway transaction address is compared
194 ** with both sets of LOW/HIGH registers. If the address is in the range
195 ** greater than or equal to IO_IO_LOW and less than IO_IO_HIGH the transaction
196 ** for forwarded to the respective GSC+ bus.
197 ** Specify IO_IO_LOW equal to or greater than IO_IO_HIGH to avoid specifying
198 ** an address space region.
199 **
200 ** In order for a Runway address to reside within GSC+ extended address space:
201 **	Runway Address [0:7]    must identically compare to 8'b11111111
202 **	Runway Address [8:11]   must be equal to IO_IO_LOW(_HV)[16:19]
203 ** 	Runway Address [12:23]  must be greater than or equal to
204 **	           IO_IO_LOW(_HV)[20:31] and less than IO_IO_HIGH(_HV)[20:31].
205 **	Runway Address [24:39]  is not used in the comparison.
206 **
207 ** When the Runway transaction is forwarded to GSC+, the GSC+ address is
208 ** as follows:
209 **	GSC+ Address[0:3]	4'b1111
210 **	GSC+ Address[4:29]	Runway Address[12:37]
211 **	GSC+ Address[30:31]	2'b00
212 **
213 ** All 4 Low/High registers must be initialized (by PDC) once the lower bus
214 ** is interrogated and address space is defined. The operating system will
215 ** modify the architectural IO_IO_LOW and IO_IO_HIGH registers following
216 ** the PDC initialization.  However, the hardware version dependent IO_IO_LOW
217 ** and IO_IO_HIGH registers should not be subsequently altered by the OS.
218 **
219 ** Writes to both sets of registers will take effect immediately, bypassing
220 ** the queues, which ensures that subsequent Runway transactions are checked
221 ** against the updated bounds values. However reads are queued, introducing
222 ** the possibility of a read being bypassed by a subsequent write to the same
223 ** register. This sequence can be avoided by having software wait for read
224 ** returns before issuing subsequent writes.
225 */
226 
227 struct ioc {
228 	struct ioa_registers __iomem *ioc_regs;  /* I/O MMU base address */
229 	u8  *res_map;	                /* resource map, bit == pdir entry */
230 	u64 *pdir_base;	                /* physical base address */
231 	u32 pdir_size; 			/* bytes, function of IOV Space size */
232 	u32 res_hint;	                /* next available IOVP -
233 					   circular search */
234 	u32 res_size;		    	/* size of resource map in bytes */
235 	spinlock_t res_lock;
236 
237 #ifdef CCIO_COLLECT_STATS
238 #define CCIO_SEARCH_SAMPLE 0x100
239 	unsigned long avg_search[CCIO_SEARCH_SAMPLE];
240 	unsigned long avg_idx;		  /* current index into avg_search */
241 	unsigned long used_pages;
242 	unsigned long msingle_calls;
243 	unsigned long msingle_pages;
244 	unsigned long msg_calls;
245 	unsigned long msg_pages;
246 	unsigned long usingle_calls;
247 	unsigned long usingle_pages;
248 	unsigned long usg_calls;
249 	unsigned long usg_pages;
250 #endif
251 	unsigned short cujo20_bug;
252 
253 	/* STUFF We don't need in performance path */
254 	u32 chainid_shift; 		/* specify bit location of chain_id */
255 	struct ioc *next;		/* Linked list of discovered iocs */
256 	const char *name;		/* device name from firmware */
257 	unsigned int hw_path;           /* the hardware path this ioc is associatd with */
258 	struct pci_dev *fake_pci_dev;   /* the fake pci_dev for non-pci devs */
259 	struct resource mmio_region[2]; /* The "routed" MMIO regions */
260 };
261 
262 static struct ioc *ioc_list;
263 static int ioc_count;
264 
265 /**************************************************************
266 *
267 *   I/O Pdir Resource Management
268 *
269 *   Bits set in the resource map are in use.
270 *   Each bit can represent a number of pages.
271 *   LSbs represent lower addresses (IOVA's).
272 *
273 *   This was was copied from sba_iommu.c. Don't try to unify
274 *   the two resource managers unless a way to have different
275 *   allocation policies is also adjusted. We'd like to avoid
276 *   I/O TLB thrashing by having resource allocation policy
277 *   match the I/O TLB replacement policy.
278 *
279 ***************************************************************/
280 #define IOVP_SIZE PAGE_SIZE
281 #define IOVP_SHIFT PAGE_SHIFT
282 #define IOVP_MASK PAGE_MASK
283 
284 /* Convert from IOVP to IOVA and vice versa. */
285 #define CCIO_IOVA(iovp,offset) ((iovp) | (offset))
286 #define CCIO_IOVP(iova) ((iova) & IOVP_MASK)
287 
288 #define PDIR_INDEX(iovp)    ((iovp)>>IOVP_SHIFT)
289 #define MKIOVP(pdir_idx)    ((long)(pdir_idx) << IOVP_SHIFT)
290 #define MKIOVA(iovp,offset) (dma_addr_t)((long)iovp | (long)offset)
291 
292 /*
293 ** Don't worry about the 150% average search length on a miss.
294 ** If the search wraps around, and passes the res_hint, it will
295 ** cause the kernel to panic anyhow.
296 */
297 #define CCIO_SEARCH_LOOP(ioc, res_idx, mask, size)  \
298        for(; res_ptr < res_end; ++res_ptr) { \
299 		int ret;\
300 		unsigned int idx;\
301 		idx = (unsigned int)((unsigned long)res_ptr - (unsigned long)ioc->res_map); \
302 		ret = iommu_is_span_boundary(idx << 3, pages_needed, 0, boundary_size);\
303 		if ((0 == (*res_ptr & mask)) && !ret) { \
304 			*res_ptr |= mask; \
305 			res_idx = idx;\
306 			ioc->res_hint = res_idx + (size >> 3); \
307 			goto resource_found; \
308 		} \
309 	}
310 
311 #define CCIO_FIND_FREE_MAPPING(ioa, res_idx, mask, size) \
312        u##size *res_ptr = (u##size *)&((ioc)->res_map[ioa->res_hint & ~((size >> 3) - 1)]); \
313        u##size *res_end = (u##size *)&(ioc)->res_map[ioa->res_size]; \
314        CCIO_SEARCH_LOOP(ioc, res_idx, mask, size); \
315        res_ptr = (u##size *)&(ioc)->res_map[0]; \
316        CCIO_SEARCH_LOOP(ioa, res_idx, mask, size);
317 
318 /*
319 ** Find available bit in this ioa's resource map.
320 ** Use a "circular" search:
321 **   o Most IOVA's are "temporary" - avg search time should be small.
322 ** o keep a history of what happened for debugging
323 ** o KISS.
324 **
325 ** Perf optimizations:
326 ** o search for log2(size) bits at a time.
327 ** o search for available resource bits using byte/word/whatever.
328 ** o use different search for "large" (eg > 4 pages) or "very large"
329 **   (eg > 16 pages) mappings.
330 */
331 
332 /**
333  * ccio_alloc_range - Allocate pages in the ioc's resource map.
334  * @ioc: The I/O Controller.
335  * @pages_needed: The requested number of pages to be mapped into the
336  * I/O Pdir...
337  *
338  * This function searches the resource map of the ioc to locate a range
339  * of available pages for the requested size.
340  */
341 static int
342 ccio_alloc_range(struct ioc *ioc, struct device *dev, size_t size)
343 {
344 	unsigned int pages_needed = size >> IOVP_SHIFT;
345 	unsigned int res_idx;
346 	unsigned long boundary_size;
347 #ifdef CCIO_COLLECT_STATS
348 	unsigned long cr_start = mfctl(16);
349 #endif
350 
351 	BUG_ON(pages_needed == 0);
352 	BUG_ON((pages_needed * IOVP_SIZE) > DMA_CHUNK_SIZE);
353 
354 	DBG_RES("%s() size: %d pages_needed %d\n",
355 		__func__, size, pages_needed);
356 
357 	/*
358 	** "seek and ye shall find"...praying never hurts either...
359 	** ggg sacrifices another 710 to the computer gods.
360 	*/
361 
362 	boundary_size = ALIGN((unsigned long long)dma_get_seg_boundary(dev) + 1,
363 			      1ULL << IOVP_SHIFT) >> IOVP_SHIFT;
364 
365 	if (pages_needed <= 8) {
366 		/*
367 		 * LAN traffic will not thrash the TLB IFF the same NIC
368 		 * uses 8 adjacent pages to map separate payload data.
369 		 * ie the same byte in the resource bit map.
370 		 */
371 #if 0
372 		/* FIXME: bit search should shift it's way through
373 		 * an unsigned long - not byte at a time. As it is now,
374 		 * we effectively allocate this byte to this mapping.
375 		 */
376 		unsigned long mask = ~(~0UL >> pages_needed);
377 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, mask, 8);
378 #else
379 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, 0xff, 8);
380 #endif
381 	} else if (pages_needed <= 16) {
382 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, 0xffff, 16);
383 	} else if (pages_needed <= 32) {
384 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, ~(unsigned int)0, 32);
385 #ifdef __LP64__
386 	} else if (pages_needed <= 64) {
387 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, ~0UL, 64);
388 #endif
389 	} else {
390 		panic("%s: %s() Too many pages to map. pages_needed: %u\n",
391 		       __FILE__,  __func__, pages_needed);
392 	}
393 
394 	panic("%s: %s() I/O MMU is out of mapping resources.\n", __FILE__,
395 	      __func__);
396 
397 resource_found:
398 
399 	DBG_RES("%s() res_idx %d res_hint: %d\n",
400 		__func__, res_idx, ioc->res_hint);
401 
402 #ifdef CCIO_COLLECT_STATS
403 	{
404 		unsigned long cr_end = mfctl(16);
405 		unsigned long tmp = cr_end - cr_start;
406 		/* check for roll over */
407 		cr_start = (cr_end < cr_start) ?  -(tmp) : (tmp);
408 	}
409 	ioc->avg_search[ioc->avg_idx++] = cr_start;
410 	ioc->avg_idx &= CCIO_SEARCH_SAMPLE - 1;
411 	ioc->used_pages += pages_needed;
412 #endif
413 	/*
414 	** return the bit address.
415 	*/
416 	return res_idx << 3;
417 }
418 
419 #define CCIO_FREE_MAPPINGS(ioc, res_idx, mask, size) \
420         u##size *res_ptr = (u##size *)&((ioc)->res_map[res_idx]); \
421         BUG_ON((*res_ptr & mask) != mask); \
422         *res_ptr &= ~(mask);
423 
424 /**
425  * ccio_free_range - Free pages from the ioc's resource map.
426  * @ioc: The I/O Controller.
427  * @iova: The I/O Virtual Address.
428  * @pages_mapped: The requested number of pages to be freed from the
429  * I/O Pdir.
430  *
431  * This function frees the resouces allocated for the iova.
432  */
433 static void
434 ccio_free_range(struct ioc *ioc, dma_addr_t iova, unsigned long pages_mapped)
435 {
436 	unsigned long iovp = CCIO_IOVP(iova);
437 	unsigned int res_idx = PDIR_INDEX(iovp) >> 3;
438 
439 	BUG_ON(pages_mapped == 0);
440 	BUG_ON((pages_mapped * IOVP_SIZE) > DMA_CHUNK_SIZE);
441 	BUG_ON(pages_mapped > BITS_PER_LONG);
442 
443 	DBG_RES("%s():  res_idx: %d pages_mapped %d\n",
444 		__func__, res_idx, pages_mapped);
445 
446 #ifdef CCIO_COLLECT_STATS
447 	ioc->used_pages -= pages_mapped;
448 #endif
449 
450 	if(pages_mapped <= 8) {
451 #if 0
452 		/* see matching comments in alloc_range */
453 		unsigned long mask = ~(~0UL >> pages_mapped);
454 		CCIO_FREE_MAPPINGS(ioc, res_idx, mask, 8);
455 #else
456 		CCIO_FREE_MAPPINGS(ioc, res_idx, 0xffUL, 8);
457 #endif
458 	} else if(pages_mapped <= 16) {
459 		CCIO_FREE_MAPPINGS(ioc, res_idx, 0xffffUL, 16);
460 	} else if(pages_mapped <= 32) {
461 		CCIO_FREE_MAPPINGS(ioc, res_idx, ~(unsigned int)0, 32);
462 #ifdef __LP64__
463 	} else if(pages_mapped <= 64) {
464 		CCIO_FREE_MAPPINGS(ioc, res_idx, ~0UL, 64);
465 #endif
466 	} else {
467 		panic("%s:%s() Too many pages to unmap.\n", __FILE__,
468 		      __func__);
469 	}
470 }
471 
472 /****************************************************************
473 **
474 **          CCIO dma_ops support routines
475 **
476 *****************************************************************/
477 
478 typedef unsigned long space_t;
479 #define KERNEL_SPACE 0
480 
481 /*
482 ** DMA "Page Type" and Hints
483 ** o if SAFE_DMA isn't set, mapping is for FAST_DMA. SAFE_DMA should be
484 **   set for subcacheline DMA transfers since we don't want to damage the
485 **   other part of a cacheline.
486 ** o SAFE_DMA must be set for "memory" allocated via pci_alloc_consistent().
487 **   This bit tells U2 to do R/M/W for partial cachelines. "Streaming"
488 **   data can avoid this if the mapping covers full cache lines.
489 ** o STOP_MOST is needed for atomicity across cachelines.
490 **   Apparently only "some EISA devices" need this.
491 **   Using CONFIG_ISA is hack. Only the IOA with EISA under it needs
492 **   to use this hint iff the EISA devices needs this feature.
493 **   According to the U2 ERS, STOP_MOST enabled pages hurt performance.
494 ** o PREFETCH should *not* be set for cases like Multiple PCI devices
495 **   behind GSCtoPCI (dino) bus converter. Only one cacheline per GSC
496 **   device can be fetched and multiply DMA streams will thrash the
497 **   prefetch buffer and burn memory bandwidth. See 6.7.3 "Prefetch Rules
498 **   and Invalidation of Prefetch Entries".
499 **
500 ** FIXME: the default hints need to be per GSC device - not global.
501 **
502 ** HP-UX dorks: linux device driver programming model is totally different
503 **    than HP-UX's. HP-UX always sets HINT_PREFETCH since it's drivers
504 **    do special things to work on non-coherent platforms...linux has to
505 **    be much more careful with this.
506 */
507 #define IOPDIR_VALID    0x01UL
508 #define HINT_SAFE_DMA   0x02UL	/* used for pci_alloc_consistent() pages */
509 #ifdef CONFIG_EISA
510 #define HINT_STOP_MOST  0x04UL	/* LSL support */
511 #else
512 #define HINT_STOP_MOST  0x00UL	/* only needed for "some EISA devices" */
513 #endif
514 #define HINT_UDPATE_ENB 0x08UL  /* not used/supported by U2 */
515 #define HINT_PREFETCH   0x10UL	/* for outbound pages which are not SAFE */
516 
517 
518 /*
519 ** Use direction (ie PCI_DMA_TODEVICE) to pick hint.
520 ** ccio_alloc_consistent() depends on this to get SAFE_DMA
521 ** when it passes in BIDIRECTIONAL flag.
522 */
523 static u32 hint_lookup[] = {
524 	[PCI_DMA_BIDIRECTIONAL]	= HINT_STOP_MOST | HINT_SAFE_DMA | IOPDIR_VALID,
525 	[PCI_DMA_TODEVICE]	= HINT_STOP_MOST | HINT_PREFETCH | IOPDIR_VALID,
526 	[PCI_DMA_FROMDEVICE]	= HINT_STOP_MOST | IOPDIR_VALID,
527 };
528 
529 /**
530  * ccio_io_pdir_entry - Initialize an I/O Pdir.
531  * @pdir_ptr: A pointer into I/O Pdir.
532  * @sid: The Space Identifier.
533  * @vba: The virtual address.
534  * @hints: The DMA Hint.
535  *
536  * Given a virtual address (vba, arg2) and space id, (sid, arg1),
537  * load the I/O PDIR entry pointed to by pdir_ptr (arg0). Each IO Pdir
538  * entry consists of 8 bytes as shown below (MSB == bit 0):
539  *
540  *
541  * WORD 0:
542  * +------+----------------+-----------------------------------------------+
543  * | Phys | Virtual Index  |               Phys                            |
544  * | 0:3  |     0:11       |               4:19                            |
545  * |4 bits|   12 bits      |              16 bits                          |
546  * +------+----------------+-----------------------------------------------+
547  * WORD 1:
548  * +-----------------------+-----------------------------------------------+
549  * |      Phys    |  Rsvd  | Prefetch |Update |Rsvd  |Lock  |Safe  |Valid  |
550  * |     20:39    |        | Enable   |Enable |      |Enable|DMA   |       |
551  * |    20 bits   | 5 bits | 1 bit    |1 bit  |2 bits|1 bit |1 bit |1 bit  |
552  * +-----------------------+-----------------------------------------------+
553  *
554  * The virtual index field is filled with the results of the LCI
555  * (Load Coherence Index) instruction.  The 8 bits used for the virtual
556  * index are bits 12:19 of the value returned by LCI.
557  */
558 static void CCIO_INLINE
559 ccio_io_pdir_entry(u64 *pdir_ptr, space_t sid, unsigned long vba,
560 		   unsigned long hints)
561 {
562 	register unsigned long pa;
563 	register unsigned long ci; /* coherent index */
564 
565 	/* We currently only support kernel addresses */
566 	BUG_ON(sid != KERNEL_SPACE);
567 
568 	mtsp(sid,1);
569 
570 	/*
571 	** WORD 1 - low order word
572 	** "hints" parm includes the VALID bit!
573 	** "dep" clobbers the physical address offset bits as well.
574 	*/
575 	pa = virt_to_phys(vba);
576 	asm volatile("depw  %1,31,12,%0" : "+r" (pa) : "r" (hints));
577 	((u32 *)pdir_ptr)[1] = (u32) pa;
578 
579 	/*
580 	** WORD 0 - high order word
581 	*/
582 
583 #ifdef __LP64__
584 	/*
585 	** get bits 12:15 of physical address
586 	** shift bits 16:31 of physical address
587 	** and deposit them
588 	*/
589 	asm volatile ("extrd,u %1,15,4,%0" : "=r" (ci) : "r" (pa));
590 	asm volatile ("extrd,u %1,31,16,%0" : "+r" (pa) : "r" (pa));
591 	asm volatile ("depd  %1,35,4,%0" : "+r" (pa) : "r" (ci));
592 #else
593 	pa = 0;
594 #endif
595 	/*
596 	** get CPU coherency index bits
597 	** Grab virtual index [0:11]
598 	** Deposit virt_idx bits into I/O PDIR word
599 	*/
600 	asm volatile ("lci %%r0(%%sr1, %1), %0" : "=r" (ci) : "r" (vba));
601 	asm volatile ("extru %1,19,12,%0" : "+r" (ci) : "r" (ci));
602 	asm volatile ("depw  %1,15,12,%0" : "+r" (pa) : "r" (ci));
603 
604 	((u32 *)pdir_ptr)[0] = (u32) pa;
605 
606 
607 	/* FIXME: PCX_W platforms don't need FDC/SYNC. (eg C360)
608 	**        PCX-U/U+ do. (eg C200/C240)
609 	**        PCX-T'? Don't know. (eg C110 or similar K-class)
610 	**
611 	** See PDC_MODEL/option 0/SW_CAP word for "Non-coherent IO-PDIR bit".
612 	**
613 	** "Since PCX-U employs an offset hash that is incompatible with
614 	** the real mode coherence index generation of U2, the PDIR entry
615 	** must be flushed to memory to retain coherence."
616 	*/
617 	asm_io_fdc(pdir_ptr);
618 	asm_io_sync();
619 }
620 
621 /**
622  * ccio_clear_io_tlb - Remove stale entries from the I/O TLB.
623  * @ioc: The I/O Controller.
624  * @iovp: The I/O Virtual Page.
625  * @byte_cnt: The requested number of bytes to be freed from the I/O Pdir.
626  *
627  * Purge invalid I/O PDIR entries from the I/O TLB.
628  *
629  * FIXME: Can we change the byte_cnt to pages_mapped?
630  */
631 static CCIO_INLINE void
632 ccio_clear_io_tlb(struct ioc *ioc, dma_addr_t iovp, size_t byte_cnt)
633 {
634 	u32 chain_size = 1 << ioc->chainid_shift;
635 
636 	iovp &= IOVP_MASK;	/* clear offset bits, just want pagenum */
637 	byte_cnt += chain_size;
638 
639 	while(byte_cnt > chain_size) {
640 		WRITE_U32(CMD_TLB_PURGE | iovp, &ioc->ioc_regs->io_command);
641 		iovp += chain_size;
642 		byte_cnt -= chain_size;
643 	}
644 }
645 
646 /**
647  * ccio_mark_invalid - Mark the I/O Pdir entries invalid.
648  * @ioc: The I/O Controller.
649  * @iova: The I/O Virtual Address.
650  * @byte_cnt: The requested number of bytes to be freed from the I/O Pdir.
651  *
652  * Mark the I/O Pdir entries invalid and blow away the corresponding I/O
653  * TLB entries.
654  *
655  * FIXME: at some threshold it might be "cheaper" to just blow
656  *        away the entire I/O TLB instead of individual entries.
657  *
658  * FIXME: Uturn has 256 TLB entries. We don't need to purge every
659  *        PDIR entry - just once for each possible TLB entry.
660  *        (We do need to maker I/O PDIR entries invalid regardless).
661  *
662  * FIXME: Can we change byte_cnt to pages_mapped?
663  */
664 static CCIO_INLINE void
665 ccio_mark_invalid(struct ioc *ioc, dma_addr_t iova, size_t byte_cnt)
666 {
667 	u32 iovp = (u32)CCIO_IOVP(iova);
668 	size_t saved_byte_cnt;
669 
670 	/* round up to nearest page size */
671 	saved_byte_cnt = byte_cnt = ALIGN(byte_cnt, IOVP_SIZE);
672 
673 	while(byte_cnt > 0) {
674 		/* invalidate one page at a time */
675 		unsigned int idx = PDIR_INDEX(iovp);
676 		char *pdir_ptr = (char *) &(ioc->pdir_base[idx]);
677 
678 		BUG_ON(idx >= (ioc->pdir_size / sizeof(u64)));
679 		pdir_ptr[7] = 0;	/* clear only VALID bit */
680 		/*
681 		** FIXME: PCX_W platforms don't need FDC/SYNC. (eg C360)
682 		**   PCX-U/U+ do. (eg C200/C240)
683 		** See PDC_MODEL/option 0/SW_CAP for "Non-coherent IO-PDIR bit".
684 		*/
685 		asm_io_fdc(pdir_ptr);
686 
687 		iovp     += IOVP_SIZE;
688 		byte_cnt -= IOVP_SIZE;
689 	}
690 
691 	asm_io_sync();
692 	ccio_clear_io_tlb(ioc, CCIO_IOVP(iova), saved_byte_cnt);
693 }
694 
695 /****************************************************************
696 **
697 **          CCIO dma_ops
698 **
699 *****************************************************************/
700 
701 /**
702  * ccio_dma_supported - Verify the IOMMU supports the DMA address range.
703  * @dev: The PCI device.
704  * @mask: A bit mask describing the DMA address range of the device.
705  */
706 static int
707 ccio_dma_supported(struct device *dev, u64 mask)
708 {
709 	if(dev == NULL) {
710 		printk(KERN_ERR MODULE_NAME ": EISA/ISA/et al not supported\n");
711 		BUG();
712 		return 0;
713 	}
714 
715 	/* only support 32-bit or better devices (ie PCI/GSC) */
716 	return (int)(mask >= 0xffffffffUL);
717 }
718 
719 /**
720  * ccio_map_single - Map an address range into the IOMMU.
721  * @dev: The PCI device.
722  * @addr: The start address of the DMA region.
723  * @size: The length of the DMA region.
724  * @direction: The direction of the DMA transaction (to/from device).
725  *
726  * This function implements the pci_map_single function.
727  */
728 static dma_addr_t
729 ccio_map_single(struct device *dev, void *addr, size_t size,
730 		enum dma_data_direction direction)
731 {
732 	int idx;
733 	struct ioc *ioc;
734 	unsigned long flags;
735 	dma_addr_t iovp;
736 	dma_addr_t offset;
737 	u64 *pdir_start;
738 	unsigned long hint = hint_lookup[(int)direction];
739 
740 	BUG_ON(!dev);
741 	ioc = GET_IOC(dev);
742 	if (!ioc)
743 		return DMA_MAPPING_ERROR;
744 
745 	BUG_ON(size <= 0);
746 
747 	/* save offset bits */
748 	offset = ((unsigned long) addr) & ~IOVP_MASK;
749 
750 	/* round up to nearest IOVP_SIZE */
751 	size = ALIGN(size + offset, IOVP_SIZE);
752 	spin_lock_irqsave(&ioc->res_lock, flags);
753 
754 #ifdef CCIO_COLLECT_STATS
755 	ioc->msingle_calls++;
756 	ioc->msingle_pages += size >> IOVP_SHIFT;
757 #endif
758 
759 	idx = ccio_alloc_range(ioc, dev, size);
760 	iovp = (dma_addr_t)MKIOVP(idx);
761 
762 	pdir_start = &(ioc->pdir_base[idx]);
763 
764 	DBG_RUN("%s() 0x%p -> 0x%lx size: %0x%x\n",
765 		__func__, addr, (long)iovp | offset, size);
766 
767 	/* If not cacheline aligned, force SAFE_DMA on the whole mess */
768 	if((size % L1_CACHE_BYTES) || ((unsigned long)addr % L1_CACHE_BYTES))
769 		hint |= HINT_SAFE_DMA;
770 
771 	while(size > 0) {
772 		ccio_io_pdir_entry(pdir_start, KERNEL_SPACE, (unsigned long)addr, hint);
773 
774 		DBG_RUN(" pdir %p %08x%08x\n",
775 			pdir_start,
776 			(u32) (((u32 *) pdir_start)[0]),
777 			(u32) (((u32 *) pdir_start)[1]));
778 		++pdir_start;
779 		addr += IOVP_SIZE;
780 		size -= IOVP_SIZE;
781 	}
782 
783 	spin_unlock_irqrestore(&ioc->res_lock, flags);
784 
785 	/* form complete address */
786 	return CCIO_IOVA(iovp, offset);
787 }
788 
789 
790 static dma_addr_t
791 ccio_map_page(struct device *dev, struct page *page, unsigned long offset,
792 		size_t size, enum dma_data_direction direction,
793 		unsigned long attrs)
794 {
795 	return ccio_map_single(dev, page_address(page) + offset, size,
796 			direction);
797 }
798 
799 
800 /**
801  * ccio_unmap_page - Unmap an address range from the IOMMU.
802  * @dev: The PCI device.
803  * @addr: The start address of the DMA region.
804  * @size: The length of the DMA region.
805  * @direction: The direction of the DMA transaction (to/from device).
806  */
807 static void
808 ccio_unmap_page(struct device *dev, dma_addr_t iova, size_t size,
809 		enum dma_data_direction direction, unsigned long attrs)
810 {
811 	struct ioc *ioc;
812 	unsigned long flags;
813 	dma_addr_t offset = iova & ~IOVP_MASK;
814 
815 	BUG_ON(!dev);
816 	ioc = GET_IOC(dev);
817 	if (!ioc) {
818 		WARN_ON(!ioc);
819 		return;
820 	}
821 
822 	DBG_RUN("%s() iovp 0x%lx/%x\n",
823 		__func__, (long)iova, size);
824 
825 	iova ^= offset;        /* clear offset bits */
826 	size += offset;
827 	size = ALIGN(size, IOVP_SIZE);
828 
829 	spin_lock_irqsave(&ioc->res_lock, flags);
830 
831 #ifdef CCIO_COLLECT_STATS
832 	ioc->usingle_calls++;
833 	ioc->usingle_pages += size >> IOVP_SHIFT;
834 #endif
835 
836 	ccio_mark_invalid(ioc, iova, size);
837 	ccio_free_range(ioc, iova, (size >> IOVP_SHIFT));
838 	spin_unlock_irqrestore(&ioc->res_lock, flags);
839 }
840 
841 /**
842  * ccio_alloc - Allocate a consistent DMA mapping.
843  * @dev: The PCI device.
844  * @size: The length of the DMA region.
845  * @dma_handle: The DMA address handed back to the device (not the cpu).
846  *
847  * This function implements the pci_alloc_consistent function.
848  */
849 static void *
850 ccio_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag,
851 		unsigned long attrs)
852 {
853       void *ret;
854 #if 0
855 /* GRANT Need to establish hierarchy for non-PCI devs as well
856 ** and then provide matching gsc_map_xxx() functions for them as well.
857 */
858 	if(!hwdev) {
859 		/* only support PCI */
860 		*dma_handle = 0;
861 		return 0;
862 	}
863 #endif
864         ret = (void *) __get_free_pages(flag, get_order(size));
865 
866 	if (ret) {
867 		memset(ret, 0, size);
868 		*dma_handle = ccio_map_single(dev, ret, size, PCI_DMA_BIDIRECTIONAL);
869 	}
870 
871 	return ret;
872 }
873 
874 /**
875  * ccio_free - Free a consistent DMA mapping.
876  * @dev: The PCI device.
877  * @size: The length of the DMA region.
878  * @cpu_addr: The cpu address returned from the ccio_alloc_consistent.
879  * @dma_handle: The device address returned from the ccio_alloc_consistent.
880  *
881  * This function implements the pci_free_consistent function.
882  */
883 static void
884 ccio_free(struct device *dev, size_t size, void *cpu_addr,
885 		dma_addr_t dma_handle, unsigned long attrs)
886 {
887 	ccio_unmap_page(dev, dma_handle, size, 0, 0);
888 	free_pages((unsigned long)cpu_addr, get_order(size));
889 }
890 
891 /*
892 ** Since 0 is a valid pdir_base index value, can't use that
893 ** to determine if a value is valid or not. Use a flag to indicate
894 ** the SG list entry contains a valid pdir index.
895 */
896 #define PIDE_FLAG 0x80000000UL
897 
898 #ifdef CCIO_COLLECT_STATS
899 #define IOMMU_MAP_STATS
900 #endif
901 #include "iommu-helpers.h"
902 
903 /**
904  * ccio_map_sg - Map the scatter/gather list into the IOMMU.
905  * @dev: The PCI device.
906  * @sglist: The scatter/gather list to be mapped in the IOMMU.
907  * @nents: The number of entries in the scatter/gather list.
908  * @direction: The direction of the DMA transaction (to/from device).
909  *
910  * This function implements the pci_map_sg function.
911  */
912 static int
913 ccio_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
914 	    enum dma_data_direction direction, unsigned long attrs)
915 {
916 	struct ioc *ioc;
917 	int coalesced, filled = 0;
918 	unsigned long flags;
919 	unsigned long hint = hint_lookup[(int)direction];
920 	unsigned long prev_len = 0, current_len = 0;
921 	int i;
922 
923 	BUG_ON(!dev);
924 	ioc = GET_IOC(dev);
925 	if (!ioc)
926 		return 0;
927 
928 	DBG_RUN_SG("%s() START %d entries\n", __func__, nents);
929 
930 	/* Fast path single entry scatterlists. */
931 	if (nents == 1) {
932 		sg_dma_address(sglist) = ccio_map_single(dev,
933 				sg_virt(sglist), sglist->length,
934 				direction);
935 		sg_dma_len(sglist) = sglist->length;
936 		return 1;
937 	}
938 
939 	for(i = 0; i < nents; i++)
940 		prev_len += sglist[i].length;
941 
942 	spin_lock_irqsave(&ioc->res_lock, flags);
943 
944 #ifdef CCIO_COLLECT_STATS
945 	ioc->msg_calls++;
946 #endif
947 
948 	/*
949 	** First coalesce the chunks and allocate I/O pdir space
950 	**
951 	** If this is one DMA stream, we can properly map using the
952 	** correct virtual address associated with each DMA page.
953 	** w/o this association, we wouldn't have coherent DMA!
954 	** Access to the virtual address is what forces a two pass algorithm.
955 	*/
956 	coalesced = iommu_coalesce_chunks(ioc, dev, sglist, nents, ccio_alloc_range);
957 
958 	/*
959 	** Program the I/O Pdir
960 	**
961 	** map the virtual addresses to the I/O Pdir
962 	** o dma_address will contain the pdir index
963 	** o dma_len will contain the number of bytes to map
964 	** o page/offset contain the virtual address.
965 	*/
966 	filled = iommu_fill_pdir(ioc, sglist, nents, hint, ccio_io_pdir_entry);
967 
968 	spin_unlock_irqrestore(&ioc->res_lock, flags);
969 
970 	BUG_ON(coalesced != filled);
971 
972 	DBG_RUN_SG("%s() DONE %d mappings\n", __func__, filled);
973 
974 	for (i = 0; i < filled; i++)
975 		current_len += sg_dma_len(sglist + i);
976 
977 	BUG_ON(current_len != prev_len);
978 
979 	return filled;
980 }
981 
982 /**
983  * ccio_unmap_sg - Unmap the scatter/gather list from the IOMMU.
984  * @dev: The PCI device.
985  * @sglist: The scatter/gather list to be unmapped from the IOMMU.
986  * @nents: The number of entries in the scatter/gather list.
987  * @direction: The direction of the DMA transaction (to/from device).
988  *
989  * This function implements the pci_unmap_sg function.
990  */
991 static void
992 ccio_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents,
993 	      enum dma_data_direction direction, unsigned long attrs)
994 {
995 	struct ioc *ioc;
996 
997 	BUG_ON(!dev);
998 	ioc = GET_IOC(dev);
999 	if (!ioc) {
1000 		WARN_ON(!ioc);
1001 		return;
1002 	}
1003 
1004 	DBG_RUN_SG("%s() START %d entries, %p,%x\n",
1005 		__func__, nents, sg_virt(sglist), sglist->length);
1006 
1007 #ifdef CCIO_COLLECT_STATS
1008 	ioc->usg_calls++;
1009 #endif
1010 
1011 	while(sg_dma_len(sglist) && nents--) {
1012 
1013 #ifdef CCIO_COLLECT_STATS
1014 		ioc->usg_pages += sg_dma_len(sglist) >> PAGE_SHIFT;
1015 #endif
1016 		ccio_unmap_page(dev, sg_dma_address(sglist),
1017 				  sg_dma_len(sglist), direction, 0);
1018 		++sglist;
1019 	}
1020 
1021 	DBG_RUN_SG("%s() DONE (nents %d)\n", __func__, nents);
1022 }
1023 
1024 static const struct dma_map_ops ccio_ops = {
1025 	.dma_supported =	ccio_dma_supported,
1026 	.alloc =		ccio_alloc,
1027 	.free =			ccio_free,
1028 	.map_page =		ccio_map_page,
1029 	.unmap_page =		ccio_unmap_page,
1030 	.map_sg = 		ccio_map_sg,
1031 	.unmap_sg = 		ccio_unmap_sg,
1032 };
1033 
1034 #ifdef CONFIG_PROC_FS
1035 static int ccio_proc_info(struct seq_file *m, void *p)
1036 {
1037 	struct ioc *ioc = ioc_list;
1038 
1039 	while (ioc != NULL) {
1040 		unsigned int total_pages = ioc->res_size << 3;
1041 #ifdef CCIO_COLLECT_STATS
1042 		unsigned long avg = 0, min, max;
1043 		int j;
1044 #endif
1045 
1046 		seq_printf(m, "%s\n", ioc->name);
1047 
1048 		seq_printf(m, "Cujo 2.0 bug    : %s\n",
1049 			   (ioc->cujo20_bug ? "yes" : "no"));
1050 
1051 		seq_printf(m, "IO PDIR size    : %d bytes (%d entries)\n",
1052 			   total_pages * 8, total_pages);
1053 
1054 #ifdef CCIO_COLLECT_STATS
1055 		seq_printf(m, "IO PDIR entries : %ld free  %ld used (%d%%)\n",
1056 			   total_pages - ioc->used_pages, ioc->used_pages,
1057 			   (int)(ioc->used_pages * 100 / total_pages));
1058 #endif
1059 
1060 		seq_printf(m, "Resource bitmap : %d bytes (%d pages)\n",
1061 			   ioc->res_size, total_pages);
1062 
1063 #ifdef CCIO_COLLECT_STATS
1064 		min = max = ioc->avg_search[0];
1065 		for(j = 0; j < CCIO_SEARCH_SAMPLE; ++j) {
1066 			avg += ioc->avg_search[j];
1067 			if(ioc->avg_search[j] > max)
1068 				max = ioc->avg_search[j];
1069 			if(ioc->avg_search[j] < min)
1070 				min = ioc->avg_search[j];
1071 		}
1072 		avg /= CCIO_SEARCH_SAMPLE;
1073 		seq_printf(m, "  Bitmap search : %ld/%ld/%ld (min/avg/max CPU Cycles)\n",
1074 			   min, avg, max);
1075 
1076 		seq_printf(m, "pci_map_single(): %8ld calls  %8ld pages (avg %d/1000)\n",
1077 			   ioc->msingle_calls, ioc->msingle_pages,
1078 			   (int)((ioc->msingle_pages * 1000)/ioc->msingle_calls));
1079 
1080 		/* KLUGE - unmap_sg calls unmap_page for each mapped page */
1081 		min = ioc->usingle_calls - ioc->usg_calls;
1082 		max = ioc->usingle_pages - ioc->usg_pages;
1083 		seq_printf(m, "pci_unmap_single: %8ld calls  %8ld pages (avg %d/1000)\n",
1084 			   min, max, (int)((max * 1000)/min));
1085 
1086 		seq_printf(m, "pci_map_sg()    : %8ld calls  %8ld pages (avg %d/1000)\n",
1087 			   ioc->msg_calls, ioc->msg_pages,
1088 			   (int)((ioc->msg_pages * 1000)/ioc->msg_calls));
1089 
1090 		seq_printf(m, "pci_unmap_sg()  : %8ld calls  %8ld pages (avg %d/1000)\n\n\n",
1091 			   ioc->usg_calls, ioc->usg_pages,
1092 			   (int)((ioc->usg_pages * 1000)/ioc->usg_calls));
1093 #endif	/* CCIO_COLLECT_STATS */
1094 
1095 		ioc = ioc->next;
1096 	}
1097 
1098 	return 0;
1099 }
1100 
1101 static int ccio_proc_bitmap_info(struct seq_file *m, void *p)
1102 {
1103 	struct ioc *ioc = ioc_list;
1104 
1105 	while (ioc != NULL) {
1106 		seq_hex_dump(m, "   ", DUMP_PREFIX_NONE, 32, 4, ioc->res_map,
1107 			     ioc->res_size, false);
1108 		seq_putc(m, '\n');
1109 		ioc = ioc->next;
1110 		break; /* XXX - remove me */
1111 	}
1112 
1113 	return 0;
1114 }
1115 #endif /* CONFIG_PROC_FS */
1116 
1117 /**
1118  * ccio_find_ioc - Find the ioc in the ioc_list
1119  * @hw_path: The hardware path of the ioc.
1120  *
1121  * This function searches the ioc_list for an ioc that matches
1122  * the provide hardware path.
1123  */
1124 static struct ioc * ccio_find_ioc(int hw_path)
1125 {
1126 	int i;
1127 	struct ioc *ioc;
1128 
1129 	ioc = ioc_list;
1130 	for (i = 0; i < ioc_count; i++) {
1131 		if (ioc->hw_path == hw_path)
1132 			return ioc;
1133 
1134 		ioc = ioc->next;
1135 	}
1136 
1137 	return NULL;
1138 }
1139 
1140 /**
1141  * ccio_get_iommu - Find the iommu which controls this device
1142  * @dev: The parisc device.
1143  *
1144  * This function searches through the registered IOMMU's and returns
1145  * the appropriate IOMMU for the device based on its hardware path.
1146  */
1147 void * ccio_get_iommu(const struct parisc_device *dev)
1148 {
1149 	dev = find_pa_parent_type(dev, HPHW_IOA);
1150 	if (!dev)
1151 		return NULL;
1152 
1153 	return ccio_find_ioc(dev->hw_path);
1154 }
1155 
1156 #define CUJO_20_STEP       0x10000000	/* inc upper nibble */
1157 
1158 /* Cujo 2.0 has a bug which will silently corrupt data being transferred
1159  * to/from certain pages.  To avoid this happening, we mark these pages
1160  * as `used', and ensure that nothing will try to allocate from them.
1161  */
1162 void __init ccio_cujo20_fixup(struct parisc_device *cujo, u32 iovp)
1163 {
1164 	unsigned int idx;
1165 	struct parisc_device *dev = parisc_parent(cujo);
1166 	struct ioc *ioc = ccio_get_iommu(dev);
1167 	u8 *res_ptr;
1168 
1169 	ioc->cujo20_bug = 1;
1170 	res_ptr = ioc->res_map;
1171 	idx = PDIR_INDEX(iovp) >> 3;
1172 
1173 	while (idx < ioc->res_size) {
1174  		res_ptr[idx] |= 0xff;
1175 		idx += PDIR_INDEX(CUJO_20_STEP) >> 3;
1176 	}
1177 }
1178 
1179 #if 0
1180 /* GRANT -  is this needed for U2 or not? */
1181 
1182 /*
1183 ** Get the size of the I/O TLB for this I/O MMU.
1184 **
1185 ** If spa_shift is non-zero (ie probably U2),
1186 ** then calculate the I/O TLB size using spa_shift.
1187 **
1188 ** Otherwise we are supposed to get the IODC entry point ENTRY TLB
1189 ** and execute it. However, both U2 and Uturn firmware supplies spa_shift.
1190 ** I think only Java (K/D/R-class too?) systems don't do this.
1191 */
1192 static int
1193 ccio_get_iotlb_size(struct parisc_device *dev)
1194 {
1195 	if (dev->spa_shift == 0) {
1196 		panic("%s() : Can't determine I/O TLB size.\n", __func__);
1197 	}
1198 	return (1 << dev->spa_shift);
1199 }
1200 #else
1201 
1202 /* Uturn supports 256 TLB entries */
1203 #define CCIO_CHAINID_SHIFT	8
1204 #define CCIO_CHAINID_MASK	0xff
1205 #endif /* 0 */
1206 
1207 /* We *can't* support JAVA (T600). Venture there at your own risk. */
1208 static const struct parisc_device_id ccio_tbl[] __initconst = {
1209 	{ HPHW_IOA, HVERSION_REV_ANY_ID, U2_IOA_RUNWAY, 0xb }, /* U2 */
1210 	{ HPHW_IOA, HVERSION_REV_ANY_ID, UTURN_IOA_RUNWAY, 0xb }, /* UTurn */
1211 	{ 0, }
1212 };
1213 
1214 static int ccio_probe(struct parisc_device *dev);
1215 
1216 static struct parisc_driver ccio_driver __refdata = {
1217 	.name =		"ccio",
1218 	.id_table =	ccio_tbl,
1219 	.probe =	ccio_probe,
1220 };
1221 
1222 /**
1223  * ccio_ioc_init - Initialize the I/O Controller
1224  * @ioc: The I/O Controller.
1225  *
1226  * Initialize the I/O Controller which includes setting up the
1227  * I/O Page Directory, the resource map, and initalizing the
1228  * U2/Uturn chip into virtual mode.
1229  */
1230 static void __init
1231 ccio_ioc_init(struct ioc *ioc)
1232 {
1233 	int i;
1234 	unsigned int iov_order;
1235 	u32 iova_space_size;
1236 
1237 	/*
1238 	** Determine IOVA Space size from memory size.
1239 	**
1240 	** Ideally, PCI drivers would register the maximum number
1241 	** of DMA they can have outstanding for each device they
1242 	** own.  Next best thing would be to guess how much DMA
1243 	** can be outstanding based on PCI Class/sub-class. Both
1244 	** methods still require some "extra" to support PCI
1245 	** Hot-Plug/Removal of PCI cards. (aka PCI OLARD).
1246 	*/
1247 
1248 	iova_space_size = (u32) (totalram_pages() / count_parisc_driver(&ccio_driver));
1249 
1250 	/* limit IOVA space size to 1MB-1GB */
1251 
1252 	if (iova_space_size < (1 << (20 - PAGE_SHIFT))) {
1253 		iova_space_size =  1 << (20 - PAGE_SHIFT);
1254 #ifdef __LP64__
1255 	} else if (iova_space_size > (1 << (30 - PAGE_SHIFT))) {
1256 		iova_space_size =  1 << (30 - PAGE_SHIFT);
1257 #endif
1258 	}
1259 
1260 	/*
1261 	** iova space must be log2() in size.
1262 	** thus, pdir/res_map will also be log2().
1263 	*/
1264 
1265 	/* We could use larger page sizes in order to *decrease* the number
1266 	** of mappings needed.  (ie 8k pages means 1/2 the mappings).
1267 	**
1268 	** Note: Grant Grunder says "Using 8k I/O pages isn't trivial either
1269 	**   since the pages must also be physically contiguous - typically
1270 	**   this is the case under linux."
1271 	*/
1272 
1273 	iov_order = get_order(iova_space_size << PAGE_SHIFT);
1274 
1275 	/* iova_space_size is now bytes, not pages */
1276 	iova_space_size = 1 << (iov_order + PAGE_SHIFT);
1277 
1278 	ioc->pdir_size = (iova_space_size / IOVP_SIZE) * sizeof(u64);
1279 
1280 	BUG_ON(ioc->pdir_size > 8 * 1024 * 1024);   /* max pdir size <= 8MB */
1281 
1282 	/* Verify it's a power of two */
1283 	BUG_ON((1 << get_order(ioc->pdir_size)) != (ioc->pdir_size >> PAGE_SHIFT));
1284 
1285 	DBG_INIT("%s() hpa 0x%p mem %luMB IOV %dMB (%d bits)\n",
1286 			__func__, ioc->ioc_regs,
1287 			(unsigned long) totalram_pages() >> (20 - PAGE_SHIFT),
1288 			iova_space_size>>20,
1289 			iov_order + PAGE_SHIFT);
1290 
1291 	ioc->pdir_base = (u64 *)__get_free_pages(GFP_KERNEL,
1292 						 get_order(ioc->pdir_size));
1293 	if(NULL == ioc->pdir_base) {
1294 		panic("%s() could not allocate I/O Page Table\n", __func__);
1295 	}
1296 	memset(ioc->pdir_base, 0, ioc->pdir_size);
1297 
1298 	BUG_ON((((unsigned long)ioc->pdir_base) & PAGE_MASK) != (unsigned long)ioc->pdir_base);
1299 	DBG_INIT(" base %p\n", ioc->pdir_base);
1300 
1301 	/* resource map size dictated by pdir_size */
1302  	ioc->res_size = (ioc->pdir_size / sizeof(u64)) >> 3;
1303 	DBG_INIT("%s() res_size 0x%x\n", __func__, ioc->res_size);
1304 
1305 	ioc->res_map = (u8 *)__get_free_pages(GFP_KERNEL,
1306 					      get_order(ioc->res_size));
1307 	if(NULL == ioc->res_map) {
1308 		panic("%s() could not allocate resource map\n", __func__);
1309 	}
1310 	memset(ioc->res_map, 0, ioc->res_size);
1311 
1312 	/* Initialize the res_hint to 16 */
1313 	ioc->res_hint = 16;
1314 
1315 	/* Initialize the spinlock */
1316 	spin_lock_init(&ioc->res_lock);
1317 
1318 	/*
1319 	** Chainid is the upper most bits of an IOVP used to determine
1320 	** which TLB entry an IOVP will use.
1321 	*/
1322 	ioc->chainid_shift = get_order(iova_space_size) + PAGE_SHIFT - CCIO_CHAINID_SHIFT;
1323 	DBG_INIT(" chainid_shift 0x%x\n", ioc->chainid_shift);
1324 
1325 	/*
1326 	** Initialize IOA hardware
1327 	*/
1328 	WRITE_U32(CCIO_CHAINID_MASK << ioc->chainid_shift,
1329 		  &ioc->ioc_regs->io_chain_id_mask);
1330 
1331 	WRITE_U32(virt_to_phys(ioc->pdir_base),
1332 		  &ioc->ioc_regs->io_pdir_base);
1333 
1334 	/*
1335 	** Go to "Virtual Mode"
1336 	*/
1337 	WRITE_U32(IOA_NORMAL_MODE, &ioc->ioc_regs->io_control);
1338 
1339 	/*
1340 	** Initialize all I/O TLB entries to 0 (Valid bit off).
1341 	*/
1342 	WRITE_U32(0, &ioc->ioc_regs->io_tlb_entry_m);
1343 	WRITE_U32(0, &ioc->ioc_regs->io_tlb_entry_l);
1344 
1345 	for(i = 1 << CCIO_CHAINID_SHIFT; i ; i--) {
1346 		WRITE_U32((CMD_TLB_DIRECT_WRITE | (i << ioc->chainid_shift)),
1347 			  &ioc->ioc_regs->io_command);
1348 	}
1349 }
1350 
1351 static void __init
1352 ccio_init_resource(struct resource *res, char *name, void __iomem *ioaddr)
1353 {
1354 	int result;
1355 
1356 	res->parent = NULL;
1357 	res->flags = IORESOURCE_MEM;
1358 	/*
1359 	 * bracing ((signed) ...) are required for 64bit kernel because
1360 	 * we only want to sign extend the lower 16 bits of the register.
1361 	 * The upper 16-bits of range registers are hardcoded to 0xffff.
1362 	 */
1363 	res->start = (unsigned long)((signed) READ_U32(ioaddr) << 16);
1364 	res->end = (unsigned long)((signed) (READ_U32(ioaddr + 4) << 16) - 1);
1365 	res->name = name;
1366 	/*
1367 	 * Check if this MMIO range is disable
1368 	 */
1369 	if (res->end + 1 == res->start)
1370 		return;
1371 
1372 	/* On some platforms (e.g. K-Class), we have already registered
1373 	 * resources for devices reported by firmware. Some are children
1374 	 * of ccio.
1375 	 * "insert" ccio ranges in the mmio hierarchy (/proc/iomem).
1376 	 */
1377 	result = insert_resource(&iomem_resource, res);
1378 	if (result < 0) {
1379 		printk(KERN_ERR "%s() failed to claim CCIO bus address space (%08lx,%08lx)\n",
1380 			__func__, (unsigned long)res->start, (unsigned long)res->end);
1381 	}
1382 }
1383 
1384 static void __init ccio_init_resources(struct ioc *ioc)
1385 {
1386 	struct resource *res = ioc->mmio_region;
1387 	char *name = kmalloc(14, GFP_KERNEL);
1388 
1389 	snprintf(name, 14, "GSC Bus [%d/]", ioc->hw_path);
1390 
1391 	ccio_init_resource(res, name, &ioc->ioc_regs->io_io_low);
1392 	ccio_init_resource(res + 1, name, &ioc->ioc_regs->io_io_low_hv);
1393 }
1394 
1395 static int new_ioc_area(struct resource *res, unsigned long size,
1396 		unsigned long min, unsigned long max, unsigned long align)
1397 {
1398 	if (max <= min)
1399 		return -EBUSY;
1400 
1401 	res->start = (max - size + 1) &~ (align - 1);
1402 	res->end = res->start + size;
1403 
1404 	/* We might be trying to expand the MMIO range to include
1405 	 * a child device that has already registered it's MMIO space.
1406 	 * Use "insert" instead of request_resource().
1407 	 */
1408 	if (!insert_resource(&iomem_resource, res))
1409 		return 0;
1410 
1411 	return new_ioc_area(res, size, min, max - size, align);
1412 }
1413 
1414 static int expand_ioc_area(struct resource *res, unsigned long size,
1415 		unsigned long min, unsigned long max, unsigned long align)
1416 {
1417 	unsigned long start, len;
1418 
1419 	if (!res->parent)
1420 		return new_ioc_area(res, size, min, max, align);
1421 
1422 	start = (res->start - size) &~ (align - 1);
1423 	len = res->end - start + 1;
1424 	if (start >= min) {
1425 		if (!adjust_resource(res, start, len))
1426 			return 0;
1427 	}
1428 
1429 	start = res->start;
1430 	len = ((size + res->end + align) &~ (align - 1)) - start;
1431 	if (start + len <= max) {
1432 		if (!adjust_resource(res, start, len))
1433 			return 0;
1434 	}
1435 
1436 	return -EBUSY;
1437 }
1438 
1439 /*
1440  * Dino calls this function.  Beware that we may get called on systems
1441  * which have no IOC (725, B180, C160L, etc) but do have a Dino.
1442  * So it's legal to find no parent IOC.
1443  *
1444  * Some other issues: one of the resources in the ioc may be unassigned.
1445  */
1446 int ccio_allocate_resource(const struct parisc_device *dev,
1447 		struct resource *res, unsigned long size,
1448 		unsigned long min, unsigned long max, unsigned long align)
1449 {
1450 	struct resource *parent = &iomem_resource;
1451 	struct ioc *ioc = ccio_get_iommu(dev);
1452 	if (!ioc)
1453 		goto out;
1454 
1455 	parent = ioc->mmio_region;
1456 	if (parent->parent &&
1457 	    !allocate_resource(parent, res, size, min, max, align, NULL, NULL))
1458 		return 0;
1459 
1460 	if ((parent + 1)->parent &&
1461 	    !allocate_resource(parent + 1, res, size, min, max, align,
1462 				NULL, NULL))
1463 		return 0;
1464 
1465 	if (!expand_ioc_area(parent, size, min, max, align)) {
1466 		__raw_writel(((parent->start)>>16) | 0xffff0000,
1467 			     &ioc->ioc_regs->io_io_low);
1468 		__raw_writel(((parent->end)>>16) | 0xffff0000,
1469 			     &ioc->ioc_regs->io_io_high);
1470 	} else if (!expand_ioc_area(parent + 1, size, min, max, align)) {
1471 		parent++;
1472 		__raw_writel(((parent->start)>>16) | 0xffff0000,
1473 			     &ioc->ioc_regs->io_io_low_hv);
1474 		__raw_writel(((parent->end)>>16) | 0xffff0000,
1475 			     &ioc->ioc_regs->io_io_high_hv);
1476 	} else {
1477 		return -EBUSY;
1478 	}
1479 
1480  out:
1481 	return allocate_resource(parent, res, size, min, max, align, NULL,NULL);
1482 }
1483 
1484 int ccio_request_resource(const struct parisc_device *dev,
1485 		struct resource *res)
1486 {
1487 	struct resource *parent;
1488 	struct ioc *ioc = ccio_get_iommu(dev);
1489 
1490 	if (!ioc) {
1491 		parent = &iomem_resource;
1492 	} else if ((ioc->mmio_region->start <= res->start) &&
1493 			(res->end <= ioc->mmio_region->end)) {
1494 		parent = ioc->mmio_region;
1495 	} else if (((ioc->mmio_region + 1)->start <= res->start) &&
1496 			(res->end <= (ioc->mmio_region + 1)->end)) {
1497 		parent = ioc->mmio_region + 1;
1498 	} else {
1499 		return -EBUSY;
1500 	}
1501 
1502 	/* "transparent" bus bridges need to register MMIO resources
1503 	 * firmware assigned them. e.g. children of hppb.c (e.g. K-class)
1504 	 * registered their resources in the PDC "bus walk" (See
1505 	 * arch/parisc/kernel/inventory.c).
1506 	 */
1507 	return insert_resource(parent, res);
1508 }
1509 
1510 /**
1511  * ccio_probe - Determine if ccio should claim this device.
1512  * @dev: The device which has been found
1513  *
1514  * Determine if ccio should claim this chip (return 0) or not (return 1).
1515  * If so, initialize the chip and tell other partners in crime they
1516  * have work to do.
1517  */
1518 static int __init ccio_probe(struct parisc_device *dev)
1519 {
1520 	int i;
1521 	struct ioc *ioc, **ioc_p = &ioc_list;
1522 	struct pci_hba_data *hba;
1523 
1524 	ioc = kzalloc(sizeof(struct ioc), GFP_KERNEL);
1525 	if (ioc == NULL) {
1526 		printk(KERN_ERR MODULE_NAME ": memory allocation failure\n");
1527 		return -ENOMEM;
1528 	}
1529 
1530 	ioc->name = dev->id.hversion == U2_IOA_RUNWAY ? "U2" : "UTurn";
1531 
1532 	printk(KERN_INFO "Found %s at 0x%lx\n", ioc->name,
1533 		(unsigned long)dev->hpa.start);
1534 
1535 	for (i = 0; i < ioc_count; i++) {
1536 		ioc_p = &(*ioc_p)->next;
1537 	}
1538 	*ioc_p = ioc;
1539 
1540 	ioc->hw_path = dev->hw_path;
1541 	ioc->ioc_regs = ioremap_nocache(dev->hpa.start, 4096);
1542 	if (!ioc->ioc_regs) {
1543 		kfree(ioc);
1544 		return -ENOMEM;
1545 	}
1546 	ccio_ioc_init(ioc);
1547 	ccio_init_resources(ioc);
1548 	hppa_dma_ops = &ccio_ops;
1549 
1550 	hba = kzalloc(sizeof(*hba), GFP_KERNEL);
1551 	/* if this fails, no I/O cards will work, so may as well bug */
1552 	BUG_ON(hba == NULL);
1553 
1554 	hba->iommu = ioc;
1555 	dev->dev.platform_data = hba;
1556 
1557 #ifdef CONFIG_PROC_FS
1558 	if (ioc_count == 0) {
1559 		proc_create_single(MODULE_NAME, 0, proc_runway_root,
1560 				ccio_proc_info);
1561 		proc_create_single(MODULE_NAME"-bitmap", 0, proc_runway_root,
1562 				ccio_proc_bitmap_info);
1563 	}
1564 #endif
1565 	ioc_count++;
1566 	return 0;
1567 }
1568 
1569 /**
1570  * ccio_init - ccio initialization procedure.
1571  *
1572  * Register this driver.
1573  */
1574 void __init ccio_init(void)
1575 {
1576 	register_parisc_driver(&ccio_driver);
1577 }
1578 
1579