xref: /openbmc/linux/drivers/parisc/ccio-dma.c (revision a09d2831)
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 
48 #include <asm/byteorder.h>
49 #include <asm/cache.h>		/* for L1_CACHE_BYTES */
50 #include <asm/uaccess.h>
51 #include <asm/page.h>
52 #include <asm/dma.h>
53 #include <asm/io.h>
54 #include <asm/hardware.h>       /* for register_module() */
55 #include <asm/parisc-device.h>
56 
57 /*
58 ** Choose "ccio" since that's what HP-UX calls it.
59 ** Make it easier for folks to migrate from one to the other :^)
60 */
61 #define MODULE_NAME "ccio"
62 
63 #undef DEBUG_CCIO_RES
64 #undef DEBUG_CCIO_RUN
65 #undef DEBUG_CCIO_INIT
66 #undef DEBUG_CCIO_RUN_SG
67 
68 #ifdef CONFIG_PROC_FS
69 /* depends on proc fs support. But costs CPU performance. */
70 #undef CCIO_COLLECT_STATS
71 #endif
72 
73 #include <asm/runway.h>		/* for proc_runway_root */
74 
75 #ifdef DEBUG_CCIO_INIT
76 #define DBG_INIT(x...)  printk(x)
77 #else
78 #define DBG_INIT(x...)
79 #endif
80 
81 #ifdef DEBUG_CCIO_RUN
82 #define DBG_RUN(x...)   printk(x)
83 #else
84 #define DBG_RUN(x...)
85 #endif
86 
87 #ifdef DEBUG_CCIO_RES
88 #define DBG_RES(x...)   printk(x)
89 #else
90 #define DBG_RES(x...)
91 #endif
92 
93 #ifdef DEBUG_CCIO_RUN_SG
94 #define DBG_RUN_SG(x...) printk(x)
95 #else
96 #define DBG_RUN_SG(x...)
97 #endif
98 
99 #define CCIO_INLINE	inline
100 #define WRITE_U32(value, addr) __raw_writel(value, addr)
101 #define READ_U32(addr) __raw_readl(addr)
102 
103 #define U2_IOA_RUNWAY 0x580
104 #define U2_BC_GSC     0x501
105 #define UTURN_IOA_RUNWAY 0x581
106 #define UTURN_BC_GSC     0x502
107 
108 #define IOA_NORMAL_MODE      0x00020080 /* IO_CONTROL to turn on CCIO        */
109 #define CMD_TLB_DIRECT_WRITE 35         /* IO_COMMAND for I/O TLB Writes     */
110 #define CMD_TLB_PURGE        33         /* IO_COMMAND to Purge I/O TLB entry */
111 
112 struct ioa_registers {
113         /* Runway Supervisory Set */
114         int32_t    unused1[12];
115         uint32_t   io_command;             /* Offset 12 */
116         uint32_t   io_status;              /* Offset 13 */
117         uint32_t   io_control;             /* Offset 14 */
118         int32_t    unused2[1];
119 
120         /* Runway Auxiliary Register Set */
121         uint32_t   io_err_resp;            /* Offset  0 */
122         uint32_t   io_err_info;            /* Offset  1 */
123         uint32_t   io_err_req;             /* Offset  2 */
124         uint32_t   io_err_resp_hi;         /* Offset  3 */
125         uint32_t   io_tlb_entry_m;         /* Offset  4 */
126         uint32_t   io_tlb_entry_l;         /* Offset  5 */
127         uint32_t   unused3[1];
128         uint32_t   io_pdir_base;           /* Offset  7 */
129         uint32_t   io_io_low_hv;           /* Offset  8 */
130         uint32_t   io_io_high_hv;          /* Offset  9 */
131         uint32_t   unused4[1];
132         uint32_t   io_chain_id_mask;       /* Offset 11 */
133         uint32_t   unused5[2];
134         uint32_t   io_io_low;              /* Offset 14 */
135         uint32_t   io_io_high;             /* Offset 15 */
136 };
137 
138 /*
139 ** IOA Registers
140 ** -------------
141 **
142 ** Runway IO_CONTROL Register (+0x38)
143 **
144 ** The Runway IO_CONTROL register controls the forwarding of transactions.
145 **
146 ** | 0  ...  13  |  14 15 | 16 ... 21 | 22 | 23 24 |  25 ... 31 |
147 ** |    HV       |   TLB  |  reserved | HV | mode  |  reserved  |
148 **
149 ** o mode field indicates the address translation of transactions
150 **   forwarded from Runway to GSC+:
151 **       Mode Name     Value        Definition
152 **       Off (default)   0          Opaque to matching addresses.
153 **       Include         1          Transparent for matching addresses.
154 **       Peek            3          Map matching addresses.
155 **
156 **       + "Off" mode: Runway transactions which match the I/O range
157 **         specified by the IO_IO_LOW/IO_IO_HIGH registers will be ignored.
158 **       + "Include" mode: all addresses within the I/O range specified
159 **         by the IO_IO_LOW and IO_IO_HIGH registers are transparently
160 **         forwarded. This is the I/O Adapter's normal operating mode.
161 **       + "Peek" mode: used during system configuration to initialize the
162 **         GSC+ bus. Runway Write_Shorts in the address range specified by
163 **         IO_IO_LOW and IO_IO_HIGH are forwarded through the I/O Adapter
164 **         *AND* the GSC+ address is remapped to the Broadcast Physical
165 **         Address space by setting the 14 high order address bits of the
166 **         32 bit GSC+ address to ones.
167 **
168 ** o TLB field affects transactions which are forwarded from GSC+ to Runway.
169 **   "Real" mode is the poweron default.
170 **
171 **   TLB Mode  Value  Description
172 **   Real        0    No TLB translation. Address is directly mapped and the
173 **                    virtual address is composed of selected physical bits.
174 **   Error       1    Software fills the TLB manually.
175 **   Normal      2    IOA fetches IO TLB misses from IO PDIR (in host memory).
176 **
177 **
178 ** IO_IO_LOW_HV	  +0x60 (HV dependent)
179 ** IO_IO_HIGH_HV  +0x64 (HV dependent)
180 ** IO_IO_LOW      +0x78	(Architected register)
181 ** IO_IO_HIGH     +0x7c	(Architected register)
182 **
183 ** IO_IO_LOW and IO_IO_HIGH set the lower and upper bounds of the
184 ** I/O Adapter address space, respectively.
185 **
186 ** 0  ... 7 | 8 ... 15 |  16   ...   31 |
187 ** 11111111 | 11111111 |      address   |
188 **
189 ** Each LOW/HIGH pair describes a disjoint address space region.
190 ** (2 per GSC+ port). Each incoming Runway transaction address is compared
191 ** with both sets of LOW/HIGH registers. If the address is in the range
192 ** greater than or equal to IO_IO_LOW and less than IO_IO_HIGH the transaction
193 ** for forwarded to the respective GSC+ bus.
194 ** Specify IO_IO_LOW equal to or greater than IO_IO_HIGH to avoid specifying
195 ** an address space region.
196 **
197 ** In order for a Runway address to reside within GSC+ extended address space:
198 **	Runway Address [0:7]    must identically compare to 8'b11111111
199 **	Runway Address [8:11]   must be equal to IO_IO_LOW(_HV)[16:19]
200 ** 	Runway Address [12:23]  must be greater than or equal to
201 **	           IO_IO_LOW(_HV)[20:31] and less than IO_IO_HIGH(_HV)[20:31].
202 **	Runway Address [24:39]  is not used in the comparison.
203 **
204 ** When the Runway transaction is forwarded to GSC+, the GSC+ address is
205 ** as follows:
206 **	GSC+ Address[0:3]	4'b1111
207 **	GSC+ Address[4:29]	Runway Address[12:37]
208 **	GSC+ Address[30:31]	2'b00
209 **
210 ** All 4 Low/High registers must be initialized (by PDC) once the lower bus
211 ** is interrogated and address space is defined. The operating system will
212 ** modify the architectural IO_IO_LOW and IO_IO_HIGH registers following
213 ** the PDC initialization.  However, the hardware version dependent IO_IO_LOW
214 ** and IO_IO_HIGH registers should not be subsequently altered by the OS.
215 **
216 ** Writes to both sets of registers will take effect immediately, bypassing
217 ** the queues, which ensures that subsequent Runway transactions are checked
218 ** against the updated bounds values. However reads are queued, introducing
219 ** the possibility of a read being bypassed by a subsequent write to the same
220 ** register. This sequence can be avoided by having software wait for read
221 ** returns before issuing subsequent writes.
222 */
223 
224 struct ioc {
225 	struct ioa_registers __iomem *ioc_regs;  /* I/O MMU base address */
226 	u8  *res_map;	                /* resource map, bit == pdir entry */
227 	u64 *pdir_base;	                /* physical base address */
228 	u32 pdir_size; 			/* bytes, function of IOV Space size */
229 	u32 res_hint;	                /* next available IOVP -
230 					   circular search */
231 	u32 res_size;		    	/* size of resource map in bytes */
232 	spinlock_t res_lock;
233 
234 #ifdef CCIO_COLLECT_STATS
235 #define CCIO_SEARCH_SAMPLE 0x100
236 	unsigned long avg_search[CCIO_SEARCH_SAMPLE];
237 	unsigned long avg_idx;		  /* current index into avg_search */
238 	unsigned long used_pages;
239 	unsigned long msingle_calls;
240 	unsigned long msingle_pages;
241 	unsigned long msg_calls;
242 	unsigned long msg_pages;
243 	unsigned long usingle_calls;
244 	unsigned long usingle_pages;
245 	unsigned long usg_calls;
246 	unsigned long usg_pages;
247 #endif
248 	unsigned short cujo20_bug;
249 
250 	/* STUFF We don't need in performance path */
251 	u32 chainid_shift; 		/* specify bit location of chain_id */
252 	struct ioc *next;		/* Linked list of discovered iocs */
253 	const char *name;		/* device name from firmware */
254 	unsigned int hw_path;           /* the hardware path this ioc is associatd with */
255 	struct pci_dev *fake_pci_dev;   /* the fake pci_dev for non-pci devs */
256 	struct resource mmio_region[2]; /* The "routed" MMIO regions */
257 };
258 
259 static struct ioc *ioc_list;
260 static int ioc_count;
261 
262 /**************************************************************
263 *
264 *   I/O Pdir Resource Management
265 *
266 *   Bits set in the resource map are in use.
267 *   Each bit can represent a number of pages.
268 *   LSbs represent lower addresses (IOVA's).
269 *
270 *   This was was copied from sba_iommu.c. Don't try to unify
271 *   the two resource managers unless a way to have different
272 *   allocation policies is also adjusted. We'd like to avoid
273 *   I/O TLB thrashing by having resource allocation policy
274 *   match the I/O TLB replacement policy.
275 *
276 ***************************************************************/
277 #define IOVP_SIZE PAGE_SIZE
278 #define IOVP_SHIFT PAGE_SHIFT
279 #define IOVP_MASK PAGE_MASK
280 
281 /* Convert from IOVP to IOVA and vice versa. */
282 #define CCIO_IOVA(iovp,offset) ((iovp) | (offset))
283 #define CCIO_IOVP(iova) ((iova) & IOVP_MASK)
284 
285 #define PDIR_INDEX(iovp)    ((iovp)>>IOVP_SHIFT)
286 #define MKIOVP(pdir_idx)    ((long)(pdir_idx) << IOVP_SHIFT)
287 #define MKIOVA(iovp,offset) (dma_addr_t)((long)iovp | (long)offset)
288 
289 /*
290 ** Don't worry about the 150% average search length on a miss.
291 ** If the search wraps around, and passes the res_hint, it will
292 ** cause the kernel to panic anyhow.
293 */
294 #define CCIO_SEARCH_LOOP(ioc, res_idx, mask, size)  \
295        for(; res_ptr < res_end; ++res_ptr) { \
296 		int ret;\
297 		unsigned int idx;\
298 		idx = (unsigned int)((unsigned long)res_ptr - (unsigned long)ioc->res_map); \
299 		ret = iommu_is_span_boundary(idx << 3, pages_needed, 0, boundary_size);\
300 		if ((0 == (*res_ptr & mask)) && !ret) { \
301 			*res_ptr |= mask; \
302 			res_idx = idx;\
303 			ioc->res_hint = res_idx + (size >> 3); \
304 			goto resource_found; \
305 		} \
306 	}
307 
308 #define CCIO_FIND_FREE_MAPPING(ioa, res_idx, mask, size) \
309        u##size *res_ptr = (u##size *)&((ioc)->res_map[ioa->res_hint & ~((size >> 3) - 1)]); \
310        u##size *res_end = (u##size *)&(ioc)->res_map[ioa->res_size]; \
311        CCIO_SEARCH_LOOP(ioc, res_idx, mask, size); \
312        res_ptr = (u##size *)&(ioc)->res_map[0]; \
313        CCIO_SEARCH_LOOP(ioa, res_idx, mask, size);
314 
315 /*
316 ** Find available bit in this ioa's resource map.
317 ** Use a "circular" search:
318 **   o Most IOVA's are "temporary" - avg search time should be small.
319 ** o keep a history of what happened for debugging
320 ** o KISS.
321 **
322 ** Perf optimizations:
323 ** o search for log2(size) bits at a time.
324 ** o search for available resource bits using byte/word/whatever.
325 ** o use different search for "large" (eg > 4 pages) or "very large"
326 **   (eg > 16 pages) mappings.
327 */
328 
329 /**
330  * ccio_alloc_range - Allocate pages in the ioc's resource map.
331  * @ioc: The I/O Controller.
332  * @pages_needed: The requested number of pages to be mapped into the
333  * I/O Pdir...
334  *
335  * This function searches the resource map of the ioc to locate a range
336  * of available pages for the requested size.
337  */
338 static int
339 ccio_alloc_range(struct ioc *ioc, struct device *dev, size_t size)
340 {
341 	unsigned int pages_needed = size >> IOVP_SHIFT;
342 	unsigned int res_idx;
343 	unsigned long boundary_size;
344 #ifdef CCIO_COLLECT_STATS
345 	unsigned long cr_start = mfctl(16);
346 #endif
347 
348 	BUG_ON(pages_needed == 0);
349 	BUG_ON((pages_needed * IOVP_SIZE) > DMA_CHUNK_SIZE);
350 
351 	DBG_RES("%s() size: %d pages_needed %d\n",
352 		__func__, size, pages_needed);
353 
354 	/*
355 	** "seek and ye shall find"...praying never hurts either...
356 	** ggg sacrifices another 710 to the computer gods.
357 	*/
358 
359 	boundary_size = ALIGN((unsigned long long)dma_get_seg_boundary(dev) + 1,
360 			      1ULL << IOVP_SHIFT) >> IOVP_SHIFT;
361 
362 	if (pages_needed <= 8) {
363 		/*
364 		 * LAN traffic will not thrash the TLB IFF the same NIC
365 		 * uses 8 adjacent pages to map separate payload data.
366 		 * ie the same byte in the resource bit map.
367 		 */
368 #if 0
369 		/* FIXME: bit search should shift it's way through
370 		 * an unsigned long - not byte at a time. As it is now,
371 		 * we effectively allocate this byte to this mapping.
372 		 */
373 		unsigned long mask = ~(~0UL >> pages_needed);
374 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, mask, 8);
375 #else
376 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, 0xff, 8);
377 #endif
378 	} else if (pages_needed <= 16) {
379 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, 0xffff, 16);
380 	} else if (pages_needed <= 32) {
381 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, ~(unsigned int)0, 32);
382 #ifdef __LP64__
383 	} else if (pages_needed <= 64) {
384 		CCIO_FIND_FREE_MAPPING(ioc, res_idx, ~0UL, 64);
385 #endif
386 	} else {
387 		panic("%s: %s() Too many pages to map. pages_needed: %u\n",
388 		       __FILE__,  __func__, pages_needed);
389 	}
390 
391 	panic("%s: %s() I/O MMU is out of mapping resources.\n", __FILE__,
392 	      __func__);
393 
394 resource_found:
395 
396 	DBG_RES("%s() res_idx %d res_hint: %d\n",
397 		__func__, res_idx, ioc->res_hint);
398 
399 #ifdef CCIO_COLLECT_STATS
400 	{
401 		unsigned long cr_end = mfctl(16);
402 		unsigned long tmp = cr_end - cr_start;
403 		/* check for roll over */
404 		cr_start = (cr_end < cr_start) ?  -(tmp) : (tmp);
405 	}
406 	ioc->avg_search[ioc->avg_idx++] = cr_start;
407 	ioc->avg_idx &= CCIO_SEARCH_SAMPLE - 1;
408 	ioc->used_pages += pages_needed;
409 #endif
410 	/*
411 	** return the bit address.
412 	*/
413 	return res_idx << 3;
414 }
415 
416 #define CCIO_FREE_MAPPINGS(ioc, res_idx, mask, size) \
417         u##size *res_ptr = (u##size *)&((ioc)->res_map[res_idx]); \
418         BUG_ON((*res_ptr & mask) != mask); \
419         *res_ptr &= ~(mask);
420 
421 /**
422  * ccio_free_range - Free pages from the ioc's resource map.
423  * @ioc: The I/O Controller.
424  * @iova: The I/O Virtual Address.
425  * @pages_mapped: The requested number of pages to be freed from the
426  * I/O Pdir.
427  *
428  * This function frees the resouces allocated for the iova.
429  */
430 static void
431 ccio_free_range(struct ioc *ioc, dma_addr_t iova, unsigned long pages_mapped)
432 {
433 	unsigned long iovp = CCIO_IOVP(iova);
434 	unsigned int res_idx = PDIR_INDEX(iovp) >> 3;
435 
436 	BUG_ON(pages_mapped == 0);
437 	BUG_ON((pages_mapped * IOVP_SIZE) > DMA_CHUNK_SIZE);
438 	BUG_ON(pages_mapped > BITS_PER_LONG);
439 
440 	DBG_RES("%s():  res_idx: %d pages_mapped %d\n",
441 		__func__, res_idx, pages_mapped);
442 
443 #ifdef CCIO_COLLECT_STATS
444 	ioc->used_pages -= pages_mapped;
445 #endif
446 
447 	if(pages_mapped <= 8) {
448 #if 0
449 		/* see matching comments in alloc_range */
450 		unsigned long mask = ~(~0UL >> pages_mapped);
451 		CCIO_FREE_MAPPINGS(ioc, res_idx, mask, 8);
452 #else
453 		CCIO_FREE_MAPPINGS(ioc, res_idx, 0xffUL, 8);
454 #endif
455 	} else if(pages_mapped <= 16) {
456 		CCIO_FREE_MAPPINGS(ioc, res_idx, 0xffffUL, 16);
457 	} else if(pages_mapped <= 32) {
458 		CCIO_FREE_MAPPINGS(ioc, res_idx, ~(unsigned int)0, 32);
459 #ifdef __LP64__
460 	} else if(pages_mapped <= 64) {
461 		CCIO_FREE_MAPPINGS(ioc, res_idx, ~0UL, 64);
462 #endif
463 	} else {
464 		panic("%s:%s() Too many pages to unmap.\n", __FILE__,
465 		      __func__);
466 	}
467 }
468 
469 /****************************************************************
470 **
471 **          CCIO dma_ops support routines
472 **
473 *****************************************************************/
474 
475 typedef unsigned long space_t;
476 #define KERNEL_SPACE 0
477 
478 /*
479 ** DMA "Page Type" and Hints
480 ** o if SAFE_DMA isn't set, mapping is for FAST_DMA. SAFE_DMA should be
481 **   set for subcacheline DMA transfers since we don't want to damage the
482 **   other part of a cacheline.
483 ** o SAFE_DMA must be set for "memory" allocated via pci_alloc_consistent().
484 **   This bit tells U2 to do R/M/W for partial cachelines. "Streaming"
485 **   data can avoid this if the mapping covers full cache lines.
486 ** o STOP_MOST is needed for atomicity across cachelines.
487 **   Apparently only "some EISA devices" need this.
488 **   Using CONFIG_ISA is hack. Only the IOA with EISA under it needs
489 **   to use this hint iff the EISA devices needs this feature.
490 **   According to the U2 ERS, STOP_MOST enabled pages hurt performance.
491 ** o PREFETCH should *not* be set for cases like Multiple PCI devices
492 **   behind GSCtoPCI (dino) bus converter. Only one cacheline per GSC
493 **   device can be fetched and multiply DMA streams will thrash the
494 **   prefetch buffer and burn memory bandwidth. See 6.7.3 "Prefetch Rules
495 **   and Invalidation of Prefetch Entries".
496 **
497 ** FIXME: the default hints need to be per GSC device - not global.
498 **
499 ** HP-UX dorks: linux device driver programming model is totally different
500 **    than HP-UX's. HP-UX always sets HINT_PREFETCH since it's drivers
501 **    do special things to work on non-coherent platforms...linux has to
502 **    be much more careful with this.
503 */
504 #define IOPDIR_VALID    0x01UL
505 #define HINT_SAFE_DMA   0x02UL	/* used for pci_alloc_consistent() pages */
506 #ifdef CONFIG_EISA
507 #define HINT_STOP_MOST  0x04UL	/* LSL support */
508 #else
509 #define HINT_STOP_MOST  0x00UL	/* only needed for "some EISA devices" */
510 #endif
511 #define HINT_UDPATE_ENB 0x08UL  /* not used/supported by U2 */
512 #define HINT_PREFETCH   0x10UL	/* for outbound pages which are not SAFE */
513 
514 
515 /*
516 ** Use direction (ie PCI_DMA_TODEVICE) to pick hint.
517 ** ccio_alloc_consistent() depends on this to get SAFE_DMA
518 ** when it passes in BIDIRECTIONAL flag.
519 */
520 static u32 hint_lookup[] = {
521 	[PCI_DMA_BIDIRECTIONAL]	= HINT_STOP_MOST | HINT_SAFE_DMA | IOPDIR_VALID,
522 	[PCI_DMA_TODEVICE]	= HINT_STOP_MOST | HINT_PREFETCH | IOPDIR_VALID,
523 	[PCI_DMA_FROMDEVICE]	= HINT_STOP_MOST | IOPDIR_VALID,
524 };
525 
526 /**
527  * ccio_io_pdir_entry - Initialize an I/O Pdir.
528  * @pdir_ptr: A pointer into I/O Pdir.
529  * @sid: The Space Identifier.
530  * @vba: The virtual address.
531  * @hints: The DMA Hint.
532  *
533  * Given a virtual address (vba, arg2) and space id, (sid, arg1),
534  * load the I/O PDIR entry pointed to by pdir_ptr (arg0). Each IO Pdir
535  * entry consists of 8 bytes as shown below (MSB == bit 0):
536  *
537  *
538  * WORD 0:
539  * +------+----------------+-----------------------------------------------+
540  * | Phys | Virtual Index  |               Phys                            |
541  * | 0:3  |     0:11       |               4:19                            |
542  * |4 bits|   12 bits      |              16 bits                          |
543  * +------+----------------+-----------------------------------------------+
544  * WORD 1:
545  * +-----------------------+-----------------------------------------------+
546  * |      Phys    |  Rsvd  | Prefetch |Update |Rsvd  |Lock  |Safe  |Valid  |
547  * |     20:39    |        | Enable   |Enable |      |Enable|DMA   |       |
548  * |    20 bits   | 5 bits | 1 bit    |1 bit  |2 bits|1 bit |1 bit |1 bit  |
549  * +-----------------------+-----------------------------------------------+
550  *
551  * The virtual index field is filled with the results of the LCI
552  * (Load Coherence Index) instruction.  The 8 bits used for the virtual
553  * index are bits 12:19 of the value returned by LCI.
554  */
555 static void CCIO_INLINE
556 ccio_io_pdir_entry(u64 *pdir_ptr, space_t sid, unsigned long vba,
557 		   unsigned long hints)
558 {
559 	register unsigned long pa;
560 	register unsigned long ci; /* coherent index */
561 
562 	/* We currently only support kernel addresses */
563 	BUG_ON(sid != KERNEL_SPACE);
564 
565 	mtsp(sid,1);
566 
567 	/*
568 	** WORD 1 - low order word
569 	** "hints" parm includes the VALID bit!
570 	** "dep" clobbers the physical address offset bits as well.
571 	*/
572 	pa = virt_to_phys(vba);
573 	asm volatile("depw  %1,31,12,%0" : "+r" (pa) : "r" (hints));
574 	((u32 *)pdir_ptr)[1] = (u32) pa;
575 
576 	/*
577 	** WORD 0 - high order word
578 	*/
579 
580 #ifdef __LP64__
581 	/*
582 	** get bits 12:15 of physical address
583 	** shift bits 16:31 of physical address
584 	** and deposit them
585 	*/
586 	asm volatile ("extrd,u %1,15,4,%0" : "=r" (ci) : "r" (pa));
587 	asm volatile ("extrd,u %1,31,16,%0" : "+r" (pa) : "r" (pa));
588 	asm volatile ("depd  %1,35,4,%0" : "+r" (pa) : "r" (ci));
589 #else
590 	pa = 0;
591 #endif
592 	/*
593 	** get CPU coherency index bits
594 	** Grab virtual index [0:11]
595 	** Deposit virt_idx bits into I/O PDIR word
596 	*/
597 	asm volatile ("lci %%r0(%%sr1, %1), %0" : "=r" (ci) : "r" (vba));
598 	asm volatile ("extru %1,19,12,%0" : "+r" (ci) : "r" (ci));
599 	asm volatile ("depw  %1,15,12,%0" : "+r" (pa) : "r" (ci));
600 
601 	((u32 *)pdir_ptr)[0] = (u32) pa;
602 
603 
604 	/* FIXME: PCX_W platforms don't need FDC/SYNC. (eg C360)
605 	**        PCX-U/U+ do. (eg C200/C240)
606 	**        PCX-T'? Don't know. (eg C110 or similar K-class)
607 	**
608 	** See PDC_MODEL/option 0/SW_CAP word for "Non-coherent IO-PDIR bit".
609 	** Hopefully we can patch (NOP) these out at boot time somehow.
610 	**
611 	** "Since PCX-U employs an offset hash that is incompatible with
612 	** the real mode coherence index generation of U2, the PDIR entry
613 	** must be flushed to memory to retain coherence."
614 	*/
615 	asm volatile("fdc %%r0(%0)" : : "r" (pdir_ptr));
616 	asm volatile("sync");
617 }
618 
619 /**
620  * ccio_clear_io_tlb - Remove stale entries from the I/O TLB.
621  * @ioc: The I/O Controller.
622  * @iovp: The I/O Virtual Page.
623  * @byte_cnt: The requested number of bytes to be freed from the I/O Pdir.
624  *
625  * Purge invalid I/O PDIR entries from the I/O TLB.
626  *
627  * FIXME: Can we change the byte_cnt to pages_mapped?
628  */
629 static CCIO_INLINE void
630 ccio_clear_io_tlb(struct ioc *ioc, dma_addr_t iovp, size_t byte_cnt)
631 {
632 	u32 chain_size = 1 << ioc->chainid_shift;
633 
634 	iovp &= IOVP_MASK;	/* clear offset bits, just want pagenum */
635 	byte_cnt += chain_size;
636 
637 	while(byte_cnt > chain_size) {
638 		WRITE_U32(CMD_TLB_PURGE | iovp, &ioc->ioc_regs->io_command);
639 		iovp += chain_size;
640 		byte_cnt -= chain_size;
641 	}
642 }
643 
644 /**
645  * ccio_mark_invalid - Mark the I/O Pdir entries invalid.
646  * @ioc: The I/O Controller.
647  * @iova: The I/O Virtual Address.
648  * @byte_cnt: The requested number of bytes to be freed from the I/O Pdir.
649  *
650  * Mark the I/O Pdir entries invalid and blow away the corresponding I/O
651  * TLB entries.
652  *
653  * FIXME: at some threshold it might be "cheaper" to just blow
654  *        away the entire I/O TLB instead of individual entries.
655  *
656  * FIXME: Uturn has 256 TLB entries. We don't need to purge every
657  *        PDIR entry - just once for each possible TLB entry.
658  *        (We do need to maker I/O PDIR entries invalid regardless).
659  *
660  * FIXME: Can we change byte_cnt to pages_mapped?
661  */
662 static CCIO_INLINE void
663 ccio_mark_invalid(struct ioc *ioc, dma_addr_t iova, size_t byte_cnt)
664 {
665 	u32 iovp = (u32)CCIO_IOVP(iova);
666 	size_t saved_byte_cnt;
667 
668 	/* round up to nearest page size */
669 	saved_byte_cnt = byte_cnt = ALIGN(byte_cnt, IOVP_SIZE);
670 
671 	while(byte_cnt > 0) {
672 		/* invalidate one page at a time */
673 		unsigned int idx = PDIR_INDEX(iovp);
674 		char *pdir_ptr = (char *) &(ioc->pdir_base[idx]);
675 
676 		BUG_ON(idx >= (ioc->pdir_size / sizeof(u64)));
677 		pdir_ptr[7] = 0;	/* clear only VALID bit */
678 		/*
679 		** FIXME: PCX_W platforms don't need FDC/SYNC. (eg C360)
680 		**   PCX-U/U+ do. (eg C200/C240)
681 		** See PDC_MODEL/option 0/SW_CAP for "Non-coherent IO-PDIR bit".
682 		**
683 		** Hopefully someone figures out how to patch (NOP) the
684 		** FDC/SYNC out at boot time.
685 		*/
686 		asm volatile("fdc %%r0(%0)" : : "r" (pdir_ptr[7]));
687 
688 		iovp     += IOVP_SIZE;
689 		byte_cnt -= IOVP_SIZE;
690 	}
691 
692 	asm volatile("sync");
693 	ccio_clear_io_tlb(ioc, CCIO_IOVP(iova), saved_byte_cnt);
694 }
695 
696 /****************************************************************
697 **
698 **          CCIO dma_ops
699 **
700 *****************************************************************/
701 
702 /**
703  * ccio_dma_supported - Verify the IOMMU supports the DMA address range.
704  * @dev: The PCI device.
705  * @mask: A bit mask describing the DMA address range of the device.
706  *
707  * This function implements the pci_dma_supported function.
708  */
709 static int
710 ccio_dma_supported(struct device *dev, u64 mask)
711 {
712 	if(dev == NULL) {
713 		printk(KERN_ERR MODULE_NAME ": EISA/ISA/et al not supported\n");
714 		BUG();
715 		return 0;
716 	}
717 
718 	/* only support 32-bit devices (ie PCI/GSC) */
719 	return (int)(mask == 0xffffffffUL);
720 }
721 
722 /**
723  * ccio_map_single - Map an address range into the IOMMU.
724  * @dev: The PCI device.
725  * @addr: The start address of the DMA region.
726  * @size: The length of the DMA region.
727  * @direction: The direction of the DMA transaction (to/from device).
728  *
729  * This function implements the pci_map_single function.
730  */
731 static dma_addr_t
732 ccio_map_single(struct device *dev, void *addr, size_t size,
733 		enum dma_data_direction direction)
734 {
735 	int idx;
736 	struct ioc *ioc;
737 	unsigned long flags;
738 	dma_addr_t iovp;
739 	dma_addr_t offset;
740 	u64 *pdir_start;
741 	unsigned long hint = hint_lookup[(int)direction];
742 
743 	BUG_ON(!dev);
744 	ioc = GET_IOC(dev);
745 
746 	BUG_ON(size <= 0);
747 
748 	/* save offset bits */
749 	offset = ((unsigned long) addr) & ~IOVP_MASK;
750 
751 	/* round up to nearest IOVP_SIZE */
752 	size = ALIGN(size + offset, IOVP_SIZE);
753 	spin_lock_irqsave(&ioc->res_lock, flags);
754 
755 #ifdef CCIO_COLLECT_STATS
756 	ioc->msingle_calls++;
757 	ioc->msingle_pages += size >> IOVP_SHIFT;
758 #endif
759 
760 	idx = ccio_alloc_range(ioc, dev, size);
761 	iovp = (dma_addr_t)MKIOVP(idx);
762 
763 	pdir_start = &(ioc->pdir_base[idx]);
764 
765 	DBG_RUN("%s() 0x%p -> 0x%lx size: %0x%x\n",
766 		__func__, addr, (long)iovp | offset, size);
767 
768 	/* If not cacheline aligned, force SAFE_DMA on the whole mess */
769 	if((size % L1_CACHE_BYTES) || ((unsigned long)addr % L1_CACHE_BYTES))
770 		hint |= HINT_SAFE_DMA;
771 
772 	while(size > 0) {
773 		ccio_io_pdir_entry(pdir_start, KERNEL_SPACE, (unsigned long)addr, hint);
774 
775 		DBG_RUN(" pdir %p %08x%08x\n",
776 			pdir_start,
777 			(u32) (((u32 *) pdir_start)[0]),
778 			(u32) (((u32 *) pdir_start)[1]));
779 		++pdir_start;
780 		addr += IOVP_SIZE;
781 		size -= IOVP_SIZE;
782 	}
783 
784 	spin_unlock_irqrestore(&ioc->res_lock, flags);
785 
786 	/* form complete address */
787 	return CCIO_IOVA(iovp, offset);
788 }
789 
790 /**
791  * ccio_unmap_single - Unmap an address range from the IOMMU.
792  * @dev: The PCI device.
793  * @addr: The start address of the DMA region.
794  * @size: The length of the DMA region.
795  * @direction: The direction of the DMA transaction (to/from device).
796  *
797  * This function implements the pci_unmap_single function.
798  */
799 static void
800 ccio_unmap_single(struct device *dev, dma_addr_t iova, size_t size,
801 		  enum dma_data_direction direction)
802 {
803 	struct ioc *ioc;
804 	unsigned long flags;
805 	dma_addr_t offset = iova & ~IOVP_MASK;
806 
807 	BUG_ON(!dev);
808 	ioc = GET_IOC(dev);
809 
810 	DBG_RUN("%s() iovp 0x%lx/%x\n",
811 		__func__, (long)iova, size);
812 
813 	iova ^= offset;        /* clear offset bits */
814 	size += offset;
815 	size = ALIGN(size, IOVP_SIZE);
816 
817 	spin_lock_irqsave(&ioc->res_lock, flags);
818 
819 #ifdef CCIO_COLLECT_STATS
820 	ioc->usingle_calls++;
821 	ioc->usingle_pages += size >> IOVP_SHIFT;
822 #endif
823 
824 	ccio_mark_invalid(ioc, iova, size);
825 	ccio_free_range(ioc, iova, (size >> IOVP_SHIFT));
826 	spin_unlock_irqrestore(&ioc->res_lock, flags);
827 }
828 
829 /**
830  * ccio_alloc_consistent - Allocate a consistent DMA mapping.
831  * @dev: The PCI device.
832  * @size: The length of the DMA region.
833  * @dma_handle: The DMA address handed back to the device (not the cpu).
834  *
835  * This function implements the pci_alloc_consistent function.
836  */
837 static void *
838 ccio_alloc_consistent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag)
839 {
840       void *ret;
841 #if 0
842 /* GRANT Need to establish hierarchy for non-PCI devs as well
843 ** and then provide matching gsc_map_xxx() functions for them as well.
844 */
845 	if(!hwdev) {
846 		/* only support PCI */
847 		*dma_handle = 0;
848 		return 0;
849 	}
850 #endif
851         ret = (void *) __get_free_pages(flag, get_order(size));
852 
853 	if (ret) {
854 		memset(ret, 0, size);
855 		*dma_handle = ccio_map_single(dev, ret, size, PCI_DMA_BIDIRECTIONAL);
856 	}
857 
858 	return ret;
859 }
860 
861 /**
862  * ccio_free_consistent - Free a consistent DMA mapping.
863  * @dev: The PCI device.
864  * @size: The length of the DMA region.
865  * @cpu_addr: The cpu address returned from the ccio_alloc_consistent.
866  * @dma_handle: The device address returned from the ccio_alloc_consistent.
867  *
868  * This function implements the pci_free_consistent function.
869  */
870 static void
871 ccio_free_consistent(struct device *dev, size_t size, void *cpu_addr,
872 		     dma_addr_t dma_handle)
873 {
874 	ccio_unmap_single(dev, dma_handle, size, 0);
875 	free_pages((unsigned long)cpu_addr, get_order(size));
876 }
877 
878 /*
879 ** Since 0 is a valid pdir_base index value, can't use that
880 ** to determine if a value is valid or not. Use a flag to indicate
881 ** the SG list entry contains a valid pdir index.
882 */
883 #define PIDE_FLAG 0x80000000UL
884 
885 #ifdef CCIO_COLLECT_STATS
886 #define IOMMU_MAP_STATS
887 #endif
888 #include "iommu-helpers.h"
889 
890 /**
891  * ccio_map_sg - Map the scatter/gather list into the IOMMU.
892  * @dev: The PCI device.
893  * @sglist: The scatter/gather list to be mapped in the IOMMU.
894  * @nents: The number of entries in the scatter/gather list.
895  * @direction: The direction of the DMA transaction (to/from device).
896  *
897  * This function implements the pci_map_sg function.
898  */
899 static int
900 ccio_map_sg(struct device *dev, struct scatterlist *sglist, int nents,
901 	    enum dma_data_direction direction)
902 {
903 	struct ioc *ioc;
904 	int coalesced, filled = 0;
905 	unsigned long flags;
906 	unsigned long hint = hint_lookup[(int)direction];
907 	unsigned long prev_len = 0, current_len = 0;
908 	int i;
909 
910 	BUG_ON(!dev);
911 	ioc = GET_IOC(dev);
912 
913 	DBG_RUN_SG("%s() START %d entries\n", __func__, nents);
914 
915 	/* Fast path single entry scatterlists. */
916 	if (nents == 1) {
917 		sg_dma_address(sglist) = ccio_map_single(dev,
918 				(void *)sg_virt_addr(sglist), sglist->length,
919 				direction);
920 		sg_dma_len(sglist) = sglist->length;
921 		return 1;
922 	}
923 
924 	for(i = 0; i < nents; i++)
925 		prev_len += sglist[i].length;
926 
927 	spin_lock_irqsave(&ioc->res_lock, flags);
928 
929 #ifdef CCIO_COLLECT_STATS
930 	ioc->msg_calls++;
931 #endif
932 
933 	/*
934 	** First coalesce the chunks and allocate I/O pdir space
935 	**
936 	** If this is one DMA stream, we can properly map using the
937 	** correct virtual address associated with each DMA page.
938 	** w/o this association, we wouldn't have coherent DMA!
939 	** Access to the virtual address is what forces a two pass algorithm.
940 	*/
941 	coalesced = iommu_coalesce_chunks(ioc, dev, sglist, nents, ccio_alloc_range);
942 
943 	/*
944 	** Program the I/O Pdir
945 	**
946 	** map the virtual addresses to the I/O Pdir
947 	** o dma_address will contain the pdir index
948 	** o dma_len will contain the number of bytes to map
949 	** o page/offset contain the virtual address.
950 	*/
951 	filled = iommu_fill_pdir(ioc, sglist, nents, hint, ccio_io_pdir_entry);
952 
953 	spin_unlock_irqrestore(&ioc->res_lock, flags);
954 
955 	BUG_ON(coalesced != filled);
956 
957 	DBG_RUN_SG("%s() DONE %d mappings\n", __func__, filled);
958 
959 	for (i = 0; i < filled; i++)
960 		current_len += sg_dma_len(sglist + i);
961 
962 	BUG_ON(current_len != prev_len);
963 
964 	return filled;
965 }
966 
967 /**
968  * ccio_unmap_sg - Unmap the scatter/gather list from the IOMMU.
969  * @dev: The PCI device.
970  * @sglist: The scatter/gather list to be unmapped from the IOMMU.
971  * @nents: The number of entries in the scatter/gather list.
972  * @direction: The direction of the DMA transaction (to/from device).
973  *
974  * This function implements the pci_unmap_sg function.
975  */
976 static void
977 ccio_unmap_sg(struct device *dev, struct scatterlist *sglist, int nents,
978 	      enum dma_data_direction direction)
979 {
980 	struct ioc *ioc;
981 
982 	BUG_ON(!dev);
983 	ioc = GET_IOC(dev);
984 
985 	DBG_RUN_SG("%s() START %d entries,  %08lx,%x\n",
986 		__func__, nents, sg_virt_addr(sglist), sglist->length);
987 
988 #ifdef CCIO_COLLECT_STATS
989 	ioc->usg_calls++;
990 #endif
991 
992 	while(sg_dma_len(sglist) && nents--) {
993 
994 #ifdef CCIO_COLLECT_STATS
995 		ioc->usg_pages += sg_dma_len(sglist) >> PAGE_SHIFT;
996 #endif
997 		ccio_unmap_single(dev, sg_dma_address(sglist),
998 				  sg_dma_len(sglist), direction);
999 		++sglist;
1000 	}
1001 
1002 	DBG_RUN_SG("%s() DONE (nents %d)\n", __func__, nents);
1003 }
1004 
1005 static struct hppa_dma_ops ccio_ops = {
1006 	.dma_supported =	ccio_dma_supported,
1007 	.alloc_consistent =	ccio_alloc_consistent,
1008 	.alloc_noncoherent =	ccio_alloc_consistent,
1009 	.free_consistent =	ccio_free_consistent,
1010 	.map_single =		ccio_map_single,
1011 	.unmap_single =		ccio_unmap_single,
1012 	.map_sg = 		ccio_map_sg,
1013 	.unmap_sg = 		ccio_unmap_sg,
1014 	.dma_sync_single_for_cpu =	NULL,	/* NOP for U2/Uturn */
1015 	.dma_sync_single_for_device =	NULL,	/* NOP for U2/Uturn */
1016 	.dma_sync_sg_for_cpu =		NULL,	/* ditto */
1017 	.dma_sync_sg_for_device =		NULL,	/* ditto */
1018 };
1019 
1020 #ifdef CONFIG_PROC_FS
1021 static int ccio_proc_info(struct seq_file *m, void *p)
1022 {
1023 	int len = 0;
1024 	struct ioc *ioc = ioc_list;
1025 
1026 	while (ioc != NULL) {
1027 		unsigned int total_pages = ioc->res_size << 3;
1028 #ifdef CCIO_COLLECT_STATS
1029 		unsigned long avg = 0, min, max;
1030 		int j;
1031 #endif
1032 
1033 		len += seq_printf(m, "%s\n", ioc->name);
1034 
1035 		len += seq_printf(m, "Cujo 2.0 bug    : %s\n",
1036 				  (ioc->cujo20_bug ? "yes" : "no"));
1037 
1038 		len += seq_printf(m, "IO PDIR size    : %d bytes (%d entries)\n",
1039 			       total_pages * 8, total_pages);
1040 
1041 #ifdef CCIO_COLLECT_STATS
1042 		len += seq_printf(m, "IO PDIR entries : %ld free  %ld used (%d%%)\n",
1043 				  total_pages - ioc->used_pages, ioc->used_pages,
1044 				  (int)(ioc->used_pages * 100 / total_pages));
1045 #endif
1046 
1047 		len += seq_printf(m, "Resource bitmap : %d bytes (%d pages)\n",
1048 				  ioc->res_size, total_pages);
1049 
1050 #ifdef CCIO_COLLECT_STATS
1051 		min = max = ioc->avg_search[0];
1052 		for(j = 0; j < CCIO_SEARCH_SAMPLE; ++j) {
1053 			avg += ioc->avg_search[j];
1054 			if(ioc->avg_search[j] > max)
1055 				max = ioc->avg_search[j];
1056 			if(ioc->avg_search[j] < min)
1057 				min = ioc->avg_search[j];
1058 		}
1059 		avg /= CCIO_SEARCH_SAMPLE;
1060 		len += seq_printf(m, "  Bitmap search : %ld/%ld/%ld (min/avg/max CPU Cycles)\n",
1061 				  min, avg, max);
1062 
1063 		len += seq_printf(m, "pci_map_single(): %8ld calls  %8ld pages (avg %d/1000)\n",
1064 				  ioc->msingle_calls, ioc->msingle_pages,
1065 				  (int)((ioc->msingle_pages * 1000)/ioc->msingle_calls));
1066 
1067 		/* KLUGE - unmap_sg calls unmap_single for each mapped page */
1068 		min = ioc->usingle_calls - ioc->usg_calls;
1069 		max = ioc->usingle_pages - ioc->usg_pages;
1070 		len += seq_printf(m, "pci_unmap_single: %8ld calls  %8ld pages (avg %d/1000)\n",
1071 				  min, max, (int)((max * 1000)/min));
1072 
1073 		len += seq_printf(m, "pci_map_sg()    : %8ld calls  %8ld pages (avg %d/1000)\n",
1074 				  ioc->msg_calls, ioc->msg_pages,
1075 				  (int)((ioc->msg_pages * 1000)/ioc->msg_calls));
1076 
1077 		len += seq_printf(m, "pci_unmap_sg()  : %8ld calls  %8ld pages (avg %d/1000)\n\n\n",
1078 				  ioc->usg_calls, ioc->usg_pages,
1079 				  (int)((ioc->usg_pages * 1000)/ioc->usg_calls));
1080 #endif	/* CCIO_COLLECT_STATS */
1081 
1082 		ioc = ioc->next;
1083 	}
1084 
1085 	return 0;
1086 }
1087 
1088 static int ccio_proc_info_open(struct inode *inode, struct file *file)
1089 {
1090 	return single_open(file, &ccio_proc_info, NULL);
1091 }
1092 
1093 static const struct file_operations ccio_proc_info_fops = {
1094 	.owner = THIS_MODULE,
1095 	.open = ccio_proc_info_open,
1096 	.read = seq_read,
1097 	.llseek = seq_lseek,
1098 	.release = single_release,
1099 };
1100 
1101 static int ccio_proc_bitmap_info(struct seq_file *m, void *p)
1102 {
1103 	int len = 0;
1104 	struct ioc *ioc = ioc_list;
1105 
1106 	while (ioc != NULL) {
1107 		u32 *res_ptr = (u32 *)ioc->res_map;
1108 		int j;
1109 
1110 		for (j = 0; j < (ioc->res_size / sizeof(u32)); j++) {
1111 			if ((j & 7) == 0)
1112 				len += seq_puts(m, "\n   ");
1113 			len += seq_printf(m, "%08x", *res_ptr);
1114 			res_ptr++;
1115 		}
1116 		len += seq_puts(m, "\n\n");
1117 		ioc = ioc->next;
1118 		break; /* XXX - remove me */
1119 	}
1120 
1121 	return 0;
1122 }
1123 
1124 static int ccio_proc_bitmap_open(struct inode *inode, struct file *file)
1125 {
1126 	return single_open(file, &ccio_proc_bitmap_info, NULL);
1127 }
1128 
1129 static const struct file_operations ccio_proc_bitmap_fops = {
1130 	.owner = THIS_MODULE,
1131 	.open = ccio_proc_bitmap_open,
1132 	.read = seq_read,
1133 	.llseek = seq_lseek,
1134 	.release = single_release,
1135 };
1136 #endif /* CONFIG_PROC_FS */
1137 
1138 /**
1139  * ccio_find_ioc - Find the ioc in the ioc_list
1140  * @hw_path: The hardware path of the ioc.
1141  *
1142  * This function searches the ioc_list for an ioc that matches
1143  * the provide hardware path.
1144  */
1145 static struct ioc * ccio_find_ioc(int hw_path)
1146 {
1147 	int i;
1148 	struct ioc *ioc;
1149 
1150 	ioc = ioc_list;
1151 	for (i = 0; i < ioc_count; i++) {
1152 		if (ioc->hw_path == hw_path)
1153 			return ioc;
1154 
1155 		ioc = ioc->next;
1156 	}
1157 
1158 	return NULL;
1159 }
1160 
1161 /**
1162  * ccio_get_iommu - Find the iommu which controls this device
1163  * @dev: The parisc device.
1164  *
1165  * This function searches through the registered IOMMU's and returns
1166  * the appropriate IOMMU for the device based on its hardware path.
1167  */
1168 void * ccio_get_iommu(const struct parisc_device *dev)
1169 {
1170 	dev = find_pa_parent_type(dev, HPHW_IOA);
1171 	if (!dev)
1172 		return NULL;
1173 
1174 	return ccio_find_ioc(dev->hw_path);
1175 }
1176 
1177 #define CUJO_20_STEP       0x10000000	/* inc upper nibble */
1178 
1179 /* Cujo 2.0 has a bug which will silently corrupt data being transferred
1180  * to/from certain pages.  To avoid this happening, we mark these pages
1181  * as `used', and ensure that nothing will try to allocate from them.
1182  */
1183 void ccio_cujo20_fixup(struct parisc_device *cujo, u32 iovp)
1184 {
1185 	unsigned int idx;
1186 	struct parisc_device *dev = parisc_parent(cujo);
1187 	struct ioc *ioc = ccio_get_iommu(dev);
1188 	u8 *res_ptr;
1189 
1190 	ioc->cujo20_bug = 1;
1191 	res_ptr = ioc->res_map;
1192 	idx = PDIR_INDEX(iovp) >> 3;
1193 
1194 	while (idx < ioc->res_size) {
1195  		res_ptr[idx] |= 0xff;
1196 		idx += PDIR_INDEX(CUJO_20_STEP) >> 3;
1197 	}
1198 }
1199 
1200 #if 0
1201 /* GRANT -  is this needed for U2 or not? */
1202 
1203 /*
1204 ** Get the size of the I/O TLB for this I/O MMU.
1205 **
1206 ** If spa_shift is non-zero (ie probably U2),
1207 ** then calculate the I/O TLB size using spa_shift.
1208 **
1209 ** Otherwise we are supposed to get the IODC entry point ENTRY TLB
1210 ** and execute it. However, both U2 and Uturn firmware supplies spa_shift.
1211 ** I think only Java (K/D/R-class too?) systems don't do this.
1212 */
1213 static int
1214 ccio_get_iotlb_size(struct parisc_device *dev)
1215 {
1216 	if (dev->spa_shift == 0) {
1217 		panic("%s() : Can't determine I/O TLB size.\n", __func__);
1218 	}
1219 	return (1 << dev->spa_shift);
1220 }
1221 #else
1222 
1223 /* Uturn supports 256 TLB entries */
1224 #define CCIO_CHAINID_SHIFT	8
1225 #define CCIO_CHAINID_MASK	0xff
1226 #endif /* 0 */
1227 
1228 /* We *can't* support JAVA (T600). Venture there at your own risk. */
1229 static const struct parisc_device_id ccio_tbl[] = {
1230 	{ HPHW_IOA, HVERSION_REV_ANY_ID, U2_IOA_RUNWAY, 0xb }, /* U2 */
1231 	{ HPHW_IOA, HVERSION_REV_ANY_ID, UTURN_IOA_RUNWAY, 0xb }, /* UTurn */
1232 	{ 0, }
1233 };
1234 
1235 static int ccio_probe(struct parisc_device *dev);
1236 
1237 static struct parisc_driver ccio_driver = {
1238 	.name =		"ccio",
1239 	.id_table =	ccio_tbl,
1240 	.probe =	ccio_probe,
1241 };
1242 
1243 /**
1244  * ccio_ioc_init - Initalize the I/O Controller
1245  * @ioc: The I/O Controller.
1246  *
1247  * Initalize the I/O Controller which includes setting up the
1248  * I/O Page Directory, the resource map, and initalizing the
1249  * U2/Uturn chip into virtual mode.
1250  */
1251 static void
1252 ccio_ioc_init(struct ioc *ioc)
1253 {
1254 	int i;
1255 	unsigned int iov_order;
1256 	u32 iova_space_size;
1257 
1258 	/*
1259 	** Determine IOVA Space size from memory size.
1260 	**
1261 	** Ideally, PCI drivers would register the maximum number
1262 	** of DMA they can have outstanding for each device they
1263 	** own.  Next best thing would be to guess how much DMA
1264 	** can be outstanding based on PCI Class/sub-class. Both
1265 	** methods still require some "extra" to support PCI
1266 	** Hot-Plug/Removal of PCI cards. (aka PCI OLARD).
1267 	*/
1268 
1269 	iova_space_size = (u32) (totalram_pages / count_parisc_driver(&ccio_driver));
1270 
1271 	/* limit IOVA space size to 1MB-1GB */
1272 
1273 	if (iova_space_size < (1 << (20 - PAGE_SHIFT))) {
1274 		iova_space_size =  1 << (20 - PAGE_SHIFT);
1275 #ifdef __LP64__
1276 	} else if (iova_space_size > (1 << (30 - PAGE_SHIFT))) {
1277 		iova_space_size =  1 << (30 - PAGE_SHIFT);
1278 #endif
1279 	}
1280 
1281 	/*
1282 	** iova space must be log2() in size.
1283 	** thus, pdir/res_map will also be log2().
1284 	*/
1285 
1286 	/* We could use larger page sizes in order to *decrease* the number
1287 	** of mappings needed.  (ie 8k pages means 1/2 the mappings).
1288 	**
1289 	** Note: Grant Grunder says "Using 8k I/O pages isn't trivial either
1290 	**   since the pages must also be physically contiguous - typically
1291 	**   this is the case under linux."
1292 	*/
1293 
1294 	iov_order = get_order(iova_space_size << PAGE_SHIFT);
1295 
1296 	/* iova_space_size is now bytes, not pages */
1297 	iova_space_size = 1 << (iov_order + PAGE_SHIFT);
1298 
1299 	ioc->pdir_size = (iova_space_size / IOVP_SIZE) * sizeof(u64);
1300 
1301 	BUG_ON(ioc->pdir_size > 8 * 1024 * 1024);   /* max pdir size <= 8MB */
1302 
1303 	/* Verify it's a power of two */
1304 	BUG_ON((1 << get_order(ioc->pdir_size)) != (ioc->pdir_size >> PAGE_SHIFT));
1305 
1306 	DBG_INIT("%s() hpa 0x%p mem %luMB IOV %dMB (%d bits)\n",
1307 			__func__, ioc->ioc_regs,
1308 			(unsigned long) totalram_pages >> (20 - PAGE_SHIFT),
1309 			iova_space_size>>20,
1310 			iov_order + PAGE_SHIFT);
1311 
1312 	ioc->pdir_base = (u64 *)__get_free_pages(GFP_KERNEL,
1313 						 get_order(ioc->pdir_size));
1314 	if(NULL == ioc->pdir_base) {
1315 		panic("%s() could not allocate I/O Page Table\n", __func__);
1316 	}
1317 	memset(ioc->pdir_base, 0, ioc->pdir_size);
1318 
1319 	BUG_ON((((unsigned long)ioc->pdir_base) & PAGE_MASK) != (unsigned long)ioc->pdir_base);
1320 	DBG_INIT(" base %p\n", ioc->pdir_base);
1321 
1322 	/* resource map size dictated by pdir_size */
1323  	ioc->res_size = (ioc->pdir_size / sizeof(u64)) >> 3;
1324 	DBG_INIT("%s() res_size 0x%x\n", __func__, ioc->res_size);
1325 
1326 	ioc->res_map = (u8 *)__get_free_pages(GFP_KERNEL,
1327 					      get_order(ioc->res_size));
1328 	if(NULL == ioc->res_map) {
1329 		panic("%s() could not allocate resource map\n", __func__);
1330 	}
1331 	memset(ioc->res_map, 0, ioc->res_size);
1332 
1333 	/* Initialize the res_hint to 16 */
1334 	ioc->res_hint = 16;
1335 
1336 	/* Initialize the spinlock */
1337 	spin_lock_init(&ioc->res_lock);
1338 
1339 	/*
1340 	** Chainid is the upper most bits of an IOVP used to determine
1341 	** which TLB entry an IOVP will use.
1342 	*/
1343 	ioc->chainid_shift = get_order(iova_space_size) + PAGE_SHIFT - CCIO_CHAINID_SHIFT;
1344 	DBG_INIT(" chainid_shift 0x%x\n", ioc->chainid_shift);
1345 
1346 	/*
1347 	** Initialize IOA hardware
1348 	*/
1349 	WRITE_U32(CCIO_CHAINID_MASK << ioc->chainid_shift,
1350 		  &ioc->ioc_regs->io_chain_id_mask);
1351 
1352 	WRITE_U32(virt_to_phys(ioc->pdir_base),
1353 		  &ioc->ioc_regs->io_pdir_base);
1354 
1355 	/*
1356 	** Go to "Virtual Mode"
1357 	*/
1358 	WRITE_U32(IOA_NORMAL_MODE, &ioc->ioc_regs->io_control);
1359 
1360 	/*
1361 	** Initialize all I/O TLB entries to 0 (Valid bit off).
1362 	*/
1363 	WRITE_U32(0, &ioc->ioc_regs->io_tlb_entry_m);
1364 	WRITE_U32(0, &ioc->ioc_regs->io_tlb_entry_l);
1365 
1366 	for(i = 1 << CCIO_CHAINID_SHIFT; i ; i--) {
1367 		WRITE_U32((CMD_TLB_DIRECT_WRITE | (i << ioc->chainid_shift)),
1368 			  &ioc->ioc_regs->io_command);
1369 	}
1370 }
1371 
1372 static void __init
1373 ccio_init_resource(struct resource *res, char *name, void __iomem *ioaddr)
1374 {
1375 	int result;
1376 
1377 	res->parent = NULL;
1378 	res->flags = IORESOURCE_MEM;
1379 	/*
1380 	 * bracing ((signed) ...) are required for 64bit kernel because
1381 	 * we only want to sign extend the lower 16 bits of the register.
1382 	 * The upper 16-bits of range registers are hardcoded to 0xffff.
1383 	 */
1384 	res->start = (unsigned long)((signed) READ_U32(ioaddr) << 16);
1385 	res->end = (unsigned long)((signed) (READ_U32(ioaddr + 4) << 16) - 1);
1386 	res->name = name;
1387 	/*
1388 	 * Check if this MMIO range is disable
1389 	 */
1390 	if (res->end + 1 == res->start)
1391 		return;
1392 
1393 	/* On some platforms (e.g. K-Class), we have already registered
1394 	 * resources for devices reported by firmware. Some are children
1395 	 * of ccio.
1396 	 * "insert" ccio ranges in the mmio hierarchy (/proc/iomem).
1397 	 */
1398 	result = insert_resource(&iomem_resource, res);
1399 	if (result < 0) {
1400 		printk(KERN_ERR "%s() failed to claim CCIO bus address space (%08lx,%08lx)\n",
1401 			__func__, (unsigned long)res->start, (unsigned long)res->end);
1402 	}
1403 }
1404 
1405 static void __init ccio_init_resources(struct ioc *ioc)
1406 {
1407 	struct resource *res = ioc->mmio_region;
1408 	char *name = kmalloc(14, GFP_KERNEL);
1409 
1410 	snprintf(name, 14, "GSC Bus [%d/]", ioc->hw_path);
1411 
1412 	ccio_init_resource(res, name, &ioc->ioc_regs->io_io_low);
1413 	ccio_init_resource(res + 1, name, &ioc->ioc_regs->io_io_low_hv);
1414 }
1415 
1416 static int new_ioc_area(struct resource *res, unsigned long size,
1417 		unsigned long min, unsigned long max, unsigned long align)
1418 {
1419 	if (max <= min)
1420 		return -EBUSY;
1421 
1422 	res->start = (max - size + 1) &~ (align - 1);
1423 	res->end = res->start + size;
1424 
1425 	/* We might be trying to expand the MMIO range to include
1426 	 * a child device that has already registered it's MMIO space.
1427 	 * Use "insert" instead of request_resource().
1428 	 */
1429 	if (!insert_resource(&iomem_resource, res))
1430 		return 0;
1431 
1432 	return new_ioc_area(res, size, min, max - size, align);
1433 }
1434 
1435 static int expand_ioc_area(struct resource *res, unsigned long size,
1436 		unsigned long min, unsigned long max, unsigned long align)
1437 {
1438 	unsigned long start, len;
1439 
1440 	if (!res->parent)
1441 		return new_ioc_area(res, size, min, max, align);
1442 
1443 	start = (res->start - size) &~ (align - 1);
1444 	len = res->end - start + 1;
1445 	if (start >= min) {
1446 		if (!adjust_resource(res, start, len))
1447 			return 0;
1448 	}
1449 
1450 	start = res->start;
1451 	len = ((size + res->end + align) &~ (align - 1)) - start;
1452 	if (start + len <= max) {
1453 		if (!adjust_resource(res, start, len))
1454 			return 0;
1455 	}
1456 
1457 	return -EBUSY;
1458 }
1459 
1460 /*
1461  * Dino calls this function.  Beware that we may get called on systems
1462  * which have no IOC (725, B180, C160L, etc) but do have a Dino.
1463  * So it's legal to find no parent IOC.
1464  *
1465  * Some other issues: one of the resources in the ioc may be unassigned.
1466  */
1467 int ccio_allocate_resource(const struct parisc_device *dev,
1468 		struct resource *res, unsigned long size,
1469 		unsigned long min, unsigned long max, unsigned long align)
1470 {
1471 	struct resource *parent = &iomem_resource;
1472 	struct ioc *ioc = ccio_get_iommu(dev);
1473 	if (!ioc)
1474 		goto out;
1475 
1476 	parent = ioc->mmio_region;
1477 	if (parent->parent &&
1478 	    !allocate_resource(parent, res, size, min, max, align, NULL, NULL))
1479 		return 0;
1480 
1481 	if ((parent + 1)->parent &&
1482 	    !allocate_resource(parent + 1, res, size, min, max, align,
1483 				NULL, NULL))
1484 		return 0;
1485 
1486 	if (!expand_ioc_area(parent, size, min, max, align)) {
1487 		__raw_writel(((parent->start)>>16) | 0xffff0000,
1488 			     &ioc->ioc_regs->io_io_low);
1489 		__raw_writel(((parent->end)>>16) | 0xffff0000,
1490 			     &ioc->ioc_regs->io_io_high);
1491 	} else if (!expand_ioc_area(parent + 1, size, min, max, align)) {
1492 		parent++;
1493 		__raw_writel(((parent->start)>>16) | 0xffff0000,
1494 			     &ioc->ioc_regs->io_io_low_hv);
1495 		__raw_writel(((parent->end)>>16) | 0xffff0000,
1496 			     &ioc->ioc_regs->io_io_high_hv);
1497 	} else {
1498 		return -EBUSY;
1499 	}
1500 
1501  out:
1502 	return allocate_resource(parent, res, size, min, max, align, NULL,NULL);
1503 }
1504 
1505 int ccio_request_resource(const struct parisc_device *dev,
1506 		struct resource *res)
1507 {
1508 	struct resource *parent;
1509 	struct ioc *ioc = ccio_get_iommu(dev);
1510 
1511 	if (!ioc) {
1512 		parent = &iomem_resource;
1513 	} else if ((ioc->mmio_region->start <= res->start) &&
1514 			(res->end <= ioc->mmio_region->end)) {
1515 		parent = ioc->mmio_region;
1516 	} else if (((ioc->mmio_region + 1)->start <= res->start) &&
1517 			(res->end <= (ioc->mmio_region + 1)->end)) {
1518 		parent = ioc->mmio_region + 1;
1519 	} else {
1520 		return -EBUSY;
1521 	}
1522 
1523 	/* "transparent" bus bridges need to register MMIO resources
1524 	 * firmware assigned them. e.g. children of hppb.c (e.g. K-class)
1525 	 * registered their resources in the PDC "bus walk" (See
1526 	 * arch/parisc/kernel/inventory.c).
1527 	 */
1528 	return insert_resource(parent, res);
1529 }
1530 
1531 /**
1532  * ccio_probe - Determine if ccio should claim this device.
1533  * @dev: The device which has been found
1534  *
1535  * Determine if ccio should claim this chip (return 0) or not (return 1).
1536  * If so, initialize the chip and tell other partners in crime they
1537  * have work to do.
1538  */
1539 static int __init ccio_probe(struct parisc_device *dev)
1540 {
1541 	int i;
1542 	struct ioc *ioc, **ioc_p = &ioc_list;
1543 
1544 	ioc = kzalloc(sizeof(struct ioc), GFP_KERNEL);
1545 	if (ioc == NULL) {
1546 		printk(KERN_ERR MODULE_NAME ": memory allocation failure\n");
1547 		return 1;
1548 	}
1549 
1550 	ioc->name = dev->id.hversion == U2_IOA_RUNWAY ? "U2" : "UTurn";
1551 
1552 	printk(KERN_INFO "Found %s at 0x%lx\n", ioc->name,
1553 		(unsigned long)dev->hpa.start);
1554 
1555 	for (i = 0; i < ioc_count; i++) {
1556 		ioc_p = &(*ioc_p)->next;
1557 	}
1558 	*ioc_p = ioc;
1559 
1560 	ioc->hw_path = dev->hw_path;
1561 	ioc->ioc_regs = ioremap_nocache(dev->hpa.start, 4096);
1562 	ccio_ioc_init(ioc);
1563 	ccio_init_resources(ioc);
1564 	hppa_dma_ops = &ccio_ops;
1565 	dev->dev.platform_data = kzalloc(sizeof(struct pci_hba_data), GFP_KERNEL);
1566 
1567 	/* if this fails, no I/O cards will work, so may as well bug */
1568 	BUG_ON(dev->dev.platform_data == NULL);
1569 	HBA_DATA(dev->dev.platform_data)->iommu = ioc;
1570 
1571 #ifdef CONFIG_PROC_FS
1572 	if (ioc_count == 0) {
1573 		proc_create(MODULE_NAME, 0, proc_runway_root,
1574 			    &ccio_proc_info_fops);
1575 		proc_create(MODULE_NAME"-bitmap", 0, proc_runway_root,
1576 			    &ccio_proc_bitmap_fops);
1577 	}
1578 #endif
1579 	ioc_count++;
1580 
1581 	parisc_has_iommu();
1582 	return 0;
1583 }
1584 
1585 /**
1586  * ccio_init - ccio initialization procedure.
1587  *
1588  * Register this driver.
1589  */
1590 void __init ccio_init(void)
1591 {
1592 	register_parisc_driver(&ccio_driver);
1593 }
1594 
1595