Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * iommu.c: IOMMU specific routines for memory management.
4 *
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 * Copyright (C) 1995,2002 Pete Zaitcev (zaitcev@yahoo.com)
7 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
8 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9 */
10
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/mm.h>
14#include <linux/slab.h>
15#include <linux/dma-map-ops.h>
16#include <linux/of.h>
17#include <linux/of_device.h>
18
19#include <asm/io.h>
20#include <asm/mxcc.h>
21#include <asm/mbus.h>
22#include <asm/cacheflush.h>
23#include <asm/tlbflush.h>
24#include <asm/bitext.h>
25#include <asm/iommu.h>
26#include <asm/dma.h>
27
28#include "mm_32.h"
29
30/*
31 * This can be sized dynamically, but we will do this
32 * only when we have a guidance about actual I/O pressures.
33 */
34#define IOMMU_RNGE IOMMU_RNGE_256MB
35#define IOMMU_START 0xF0000000
36#define IOMMU_WINSIZE (256*1024*1024U)
37#define IOMMU_NPTES (IOMMU_WINSIZE/PAGE_SIZE) /* 64K PTEs, 256KB */
38#define IOMMU_ORDER 6 /* 4096 * (1<<6) */
39
40static int viking_flush;
41/* viking.S */
42extern void viking_flush_page(unsigned long page);
43extern void viking_mxcc_flush_page(unsigned long page);
44
45/*
46 * Values precomputed according to CPU type.
47 */
48static unsigned int ioperm_noc; /* Consistent mapping iopte flags */
49static pgprot_t dvma_prot; /* Consistent mapping pte flags */
50
51#define IOPERM (IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID)
52#define MKIOPTE(pfn, perm) (((((pfn)<<8) & IOPTE_PAGE) | (perm)) & ~IOPTE_WAZ)
53
54static const struct dma_map_ops sbus_iommu_dma_gflush_ops;
55static const struct dma_map_ops sbus_iommu_dma_pflush_ops;
56
57static void __init sbus_iommu_init(struct platform_device *op)
58{
59 struct iommu_struct *iommu;
60 unsigned int impl, vers;
61 unsigned long *bitmap;
62 unsigned long control;
63 unsigned long base;
64 unsigned long tmp;
65
66 iommu = kmalloc(sizeof(struct iommu_struct), GFP_KERNEL);
67 if (!iommu) {
68 prom_printf("Unable to allocate iommu structure\n");
69 prom_halt();
70 }
71
72 iommu->regs = of_ioremap(&op->resource[0], 0, PAGE_SIZE * 3,
73 "iommu_regs");
74 if (!iommu->regs) {
75 prom_printf("Cannot map IOMMU registers\n");
76 prom_halt();
77 }
78
79 control = sbus_readl(&iommu->regs->control);
80 impl = (control & IOMMU_CTRL_IMPL) >> 28;
81 vers = (control & IOMMU_CTRL_VERS) >> 24;
82 control &= ~(IOMMU_CTRL_RNGE);
83 control |= (IOMMU_RNGE_256MB | IOMMU_CTRL_ENAB);
84 sbus_writel(control, &iommu->regs->control);
85
86 iommu_invalidate(iommu->regs);
87 iommu->start = IOMMU_START;
88 iommu->end = 0xffffffff;
89
90 /* Allocate IOMMU page table */
91 /* Stupid alignment constraints give me a headache.
92 We need 256K or 512K or 1M or 2M area aligned to
93 its size and current gfp will fortunately give
94 it to us. */
95 tmp = __get_free_pages(GFP_KERNEL, IOMMU_ORDER);
96 if (!tmp) {
97 prom_printf("Unable to allocate iommu table [0x%lx]\n",
98 IOMMU_NPTES * sizeof(iopte_t));
99 prom_halt();
100 }
101 iommu->page_table = (iopte_t *)tmp;
102
103 /* Initialize new table. */
104 memset(iommu->page_table, 0, IOMMU_NPTES*sizeof(iopte_t));
105 flush_cache_all();
106 flush_tlb_all();
107
108 base = __pa((unsigned long)iommu->page_table) >> 4;
109 sbus_writel(base, &iommu->regs->base);
110 iommu_invalidate(iommu->regs);
111
112 bitmap = kmalloc(IOMMU_NPTES>>3, GFP_KERNEL);
113 if (!bitmap) {
114 prom_printf("Unable to allocate iommu bitmap [%d]\n",
115 (int)(IOMMU_NPTES>>3));
116 prom_halt();
117 }
118 bit_map_init(&iommu->usemap, bitmap, IOMMU_NPTES);
119 /* To be coherent on HyperSparc, the page color of DVMA
120 * and physical addresses must match.
121 */
122 if (srmmu_modtype == HyperSparc)
123 iommu->usemap.num_colors = vac_cache_size >> PAGE_SHIFT;
124 else
125 iommu->usemap.num_colors = 1;
126
127 printk(KERN_INFO "IOMMU: impl %d vers %d table 0x%p[%d B] map [%d b]\n",
128 impl, vers, iommu->page_table,
129 (int)(IOMMU_NPTES*sizeof(iopte_t)), (int)IOMMU_NPTES);
130
131 op->dev.archdata.iommu = iommu;
132
133 if (flush_page_for_dma_global)
134 op->dev.dma_ops = &sbus_iommu_dma_gflush_ops;
135 else
136 op->dev.dma_ops = &sbus_iommu_dma_pflush_ops;
137}
138
139static int __init iommu_init(void)
140{
141 struct device_node *dp;
142
143 for_each_node_by_name(dp, "iommu") {
144 struct platform_device *op = of_find_device_by_node(dp);
145
146 sbus_iommu_init(op);
147 of_propagate_archdata(op);
148 }
149
150 return 0;
151}
152
153subsys_initcall(iommu_init);
154
155/* Flush the iotlb entries to ram. */
156/* This could be better if we didn't have to flush whole pages. */
157static void iommu_flush_iotlb(iopte_t *iopte, unsigned int niopte)
158{
159 unsigned long start;
160 unsigned long end;
161
162 start = (unsigned long)iopte;
163 end = PAGE_ALIGN(start + niopte*sizeof(iopte_t));
164 start &= PAGE_MASK;
165 if (viking_mxcc_present) {
166 while(start < end) {
167 viking_mxcc_flush_page(start);
168 start += PAGE_SIZE;
169 }
170 } else if (viking_flush) {
171 while(start < end) {
172 viking_flush_page(start);
173 start += PAGE_SIZE;
174 }
175 } else {
176 while(start < end) {
177 __flush_page_to_ram(start);
178 start += PAGE_SIZE;
179 }
180 }
181}
182
183static dma_addr_t __sbus_iommu_map_page(struct device *dev, struct page *page,
184 unsigned long offset, size_t len, bool per_page_flush)
185{
186 struct iommu_struct *iommu = dev->archdata.iommu;
187 phys_addr_t paddr = page_to_phys(page) + offset;
188 unsigned long off = paddr & ~PAGE_MASK;
189 unsigned long npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
190 unsigned long pfn = __phys_to_pfn(paddr);
191 unsigned int busa, busa0;
192 iopte_t *iopte, *iopte0;
193 int ioptex, i;
194
195 /* XXX So what is maxphys for us and how do drivers know it? */
196 if (!len || len > 256 * 1024)
197 return DMA_MAPPING_ERROR;
198
199 /*
200 * We expect unmapped highmem pages to be not in the cache.
201 * XXX Is this a good assumption?
202 * XXX What if someone else unmaps it here and races us?
203 */
204 if (per_page_flush && !PageHighMem(page)) {
205 unsigned long vaddr, p;
206
207 vaddr = (unsigned long)page_address(page) + offset;
208 for (p = vaddr & PAGE_MASK; p < vaddr + len; p += PAGE_SIZE)
209 flush_page_for_dma(p);
210 }
211
212 /* page color = pfn of page */
213 ioptex = bit_map_string_get(&iommu->usemap, npages, pfn);
214 if (ioptex < 0)
215 panic("iommu out");
216 busa0 = iommu->start + (ioptex << PAGE_SHIFT);
217 iopte0 = &iommu->page_table[ioptex];
218
219 busa = busa0;
220 iopte = iopte0;
221 for (i = 0; i < npages; i++) {
222 iopte_val(*iopte) = MKIOPTE(pfn, IOPERM);
223 iommu_invalidate_page(iommu->regs, busa);
224 busa += PAGE_SIZE;
225 iopte++;
226 pfn++;
227 }
228
229 iommu_flush_iotlb(iopte0, npages);
230 return busa0 + off;
231}
232
233static dma_addr_t sbus_iommu_map_page_gflush(struct device *dev,
234 struct page *page, unsigned long offset, size_t len,
235 enum dma_data_direction dir, unsigned long attrs)
236{
237 flush_page_for_dma(0);
238 return __sbus_iommu_map_page(dev, page, offset, len, false);
239}
240
241static dma_addr_t sbus_iommu_map_page_pflush(struct device *dev,
242 struct page *page, unsigned long offset, size_t len,
243 enum dma_data_direction dir, unsigned long attrs)
244{
245 return __sbus_iommu_map_page(dev, page, offset, len, true);
246}
247
248static int __sbus_iommu_map_sg(struct device *dev, struct scatterlist *sgl,
249 int nents, enum dma_data_direction dir, unsigned long attrs,
250 bool per_page_flush)
251{
252 struct scatterlist *sg;
253 int j;
254
255 for_each_sg(sgl, sg, nents, j) {
256 sg->dma_address =__sbus_iommu_map_page(dev, sg_page(sg),
257 sg->offset, sg->length, per_page_flush);
258 if (sg->dma_address == DMA_MAPPING_ERROR)
259 return -EIO;
260 sg->dma_length = sg->length;
261 }
262
263 return nents;
264}
265
266static int sbus_iommu_map_sg_gflush(struct device *dev, struct scatterlist *sgl,
267 int nents, enum dma_data_direction dir, unsigned long attrs)
268{
269 flush_page_for_dma(0);
270 return __sbus_iommu_map_sg(dev, sgl, nents, dir, attrs, false);
271}
272
273static int sbus_iommu_map_sg_pflush(struct device *dev, struct scatterlist *sgl,
274 int nents, enum dma_data_direction dir, unsigned long attrs)
275{
276 return __sbus_iommu_map_sg(dev, sgl, nents, dir, attrs, true);
277}
278
279static void sbus_iommu_unmap_page(struct device *dev, dma_addr_t dma_addr,
280 size_t len, enum dma_data_direction dir, unsigned long attrs)
281{
282 struct iommu_struct *iommu = dev->archdata.iommu;
283 unsigned int busa = dma_addr & PAGE_MASK;
284 unsigned long off = dma_addr & ~PAGE_MASK;
285 unsigned int npages = (off + len + PAGE_SIZE-1) >> PAGE_SHIFT;
286 unsigned int ioptex = (busa - iommu->start) >> PAGE_SHIFT;
287 unsigned int i;
288
289 BUG_ON(busa < iommu->start);
290 for (i = 0; i < npages; i++) {
291 iopte_val(iommu->page_table[ioptex + i]) = 0;
292 iommu_invalidate_page(iommu->regs, busa);
293 busa += PAGE_SIZE;
294 }
295 bit_map_clear(&iommu->usemap, ioptex, npages);
296}
297
298static void sbus_iommu_unmap_sg(struct device *dev, struct scatterlist *sgl,
299 int nents, enum dma_data_direction dir, unsigned long attrs)
300{
301 struct scatterlist *sg;
302 int i;
303
304 for_each_sg(sgl, sg, nents, i) {
305 sbus_iommu_unmap_page(dev, sg->dma_address, sg->length, dir,
306 attrs);
307 sg->dma_address = 0x21212121;
308 }
309}
310
311#ifdef CONFIG_SBUS
312static void *sbus_iommu_alloc(struct device *dev, size_t len,
313 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
314{
315 struct iommu_struct *iommu = dev->archdata.iommu;
316 unsigned long va, addr, page, end, ret;
317 iopte_t *iopte = iommu->page_table;
318 iopte_t *first;
319 int ioptex;
320
321 /* XXX So what is maxphys for us and how do drivers know it? */
322 if (!len || len > 256 * 1024)
323 return NULL;
324
325 len = PAGE_ALIGN(len);
326 va = __get_free_pages(gfp | __GFP_ZERO, get_order(len));
327 if (va == 0)
328 return NULL;
329
330 addr = ret = sparc_dma_alloc_resource(dev, len);
331 if (!addr)
332 goto out_free_pages;
333
334 BUG_ON((va & ~PAGE_MASK) != 0);
335 BUG_ON((addr & ~PAGE_MASK) != 0);
336 BUG_ON((len & ~PAGE_MASK) != 0);
337
338 /* page color = physical address */
339 ioptex = bit_map_string_get(&iommu->usemap, len >> PAGE_SHIFT,
340 addr >> PAGE_SHIFT);
341 if (ioptex < 0)
342 panic("iommu out");
343
344 iopte += ioptex;
345 first = iopte;
346 end = addr + len;
347 while(addr < end) {
348 page = va;
349 {
350 pmd_t *pmdp;
351 pte_t *ptep;
352
353 if (viking_mxcc_present)
354 viking_mxcc_flush_page(page);
355 else if (viking_flush)
356 viking_flush_page(page);
357 else
358 __flush_page_to_ram(page);
359
360 pmdp = pmd_off_k(addr);
361 ptep = pte_offset_map(pmdp, addr);
362
363 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
364 }
365 iopte_val(*iopte++) =
366 MKIOPTE(page_to_pfn(virt_to_page(page)), ioperm_noc);
367 addr += PAGE_SIZE;
368 va += PAGE_SIZE;
369 }
370 /* P3: why do we need this?
371 *
372 * DAVEM: Because there are several aspects, none of which
373 * are handled by a single interface. Some cpus are
374 * completely not I/O DMA coherent, and some have
375 * virtually indexed caches. The driver DMA flushing
376 * methods handle the former case, but here during
377 * IOMMU page table modifications, and usage of non-cacheable
378 * cpu mappings of pages potentially in the cpu caches, we have
379 * to handle the latter case as well.
380 */
381 flush_cache_all();
382 iommu_flush_iotlb(first, len >> PAGE_SHIFT);
383 flush_tlb_all();
384 iommu_invalidate(iommu->regs);
385
386 *dma_handle = iommu->start + (ioptex << PAGE_SHIFT);
387 return (void *)ret;
388
389out_free_pages:
390 free_pages(va, get_order(len));
391 return NULL;
392}
393
394static void sbus_iommu_free(struct device *dev, size_t len, void *cpu_addr,
395 dma_addr_t busa, unsigned long attrs)
396{
397 struct iommu_struct *iommu = dev->archdata.iommu;
398 iopte_t *iopte = iommu->page_table;
399 struct page *page = virt_to_page(cpu_addr);
400 int ioptex = (busa - iommu->start) >> PAGE_SHIFT;
401 unsigned long end;
402
403 if (!sparc_dma_free_resource(cpu_addr, len))
404 return;
405
406 BUG_ON((busa & ~PAGE_MASK) != 0);
407 BUG_ON((len & ~PAGE_MASK) != 0);
408
409 iopte += ioptex;
410 end = busa + len;
411 while (busa < end) {
412 iopte_val(*iopte++) = 0;
413 busa += PAGE_SIZE;
414 }
415 flush_tlb_all();
416 iommu_invalidate(iommu->regs);
417 bit_map_clear(&iommu->usemap, ioptex, len >> PAGE_SHIFT);
418
419 __free_pages(page, get_order(len));
420}
421#endif
422
423static const struct dma_map_ops sbus_iommu_dma_gflush_ops = {
424#ifdef CONFIG_SBUS
425 .alloc = sbus_iommu_alloc,
426 .free = sbus_iommu_free,
427#endif
428 .map_page = sbus_iommu_map_page_gflush,
429 .unmap_page = sbus_iommu_unmap_page,
430 .map_sg = sbus_iommu_map_sg_gflush,
431 .unmap_sg = sbus_iommu_unmap_sg,
432};
433
434static const struct dma_map_ops sbus_iommu_dma_pflush_ops = {
435#ifdef CONFIG_SBUS
436 .alloc = sbus_iommu_alloc,
437 .free = sbus_iommu_free,
438#endif
439 .map_page = sbus_iommu_map_page_pflush,
440 .unmap_page = sbus_iommu_unmap_page,
441 .map_sg = sbus_iommu_map_sg_pflush,
442 .unmap_sg = sbus_iommu_unmap_sg,
443};
444
445void __init ld_mmu_iommu(void)
446{
447 if (viking_mxcc_present || srmmu_modtype == HyperSparc) {
448 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
449 ioperm_noc = IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID;
450 } else {
451 dvma_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV);
452 ioperm_noc = IOPTE_WRITE | IOPTE_VALID;
453 }
454}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * iommu.c: IOMMU specific routines for memory management.
4 *
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 * Copyright (C) 1995,2002 Pete Zaitcev (zaitcev@yahoo.com)
7 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
8 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
9 */
10
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/mm.h>
14#include <linux/slab.h>
15#include <linux/highmem.h> /* pte_offset_map => kmap_atomic */
16#include <linux/dma-mapping.h>
17#include <linux/of.h>
18#include <linux/of_device.h>
19
20#include <asm/pgalloc.h>
21#include <asm/pgtable.h>
22#include <asm/io.h>
23#include <asm/mxcc.h>
24#include <asm/mbus.h>
25#include <asm/cacheflush.h>
26#include <asm/tlbflush.h>
27#include <asm/bitext.h>
28#include <asm/iommu.h>
29#include <asm/dma.h>
30
31#include "mm_32.h"
32
33/*
34 * This can be sized dynamically, but we will do this
35 * only when we have a guidance about actual I/O pressures.
36 */
37#define IOMMU_RNGE IOMMU_RNGE_256MB
38#define IOMMU_START 0xF0000000
39#define IOMMU_WINSIZE (256*1024*1024U)
40#define IOMMU_NPTES (IOMMU_WINSIZE/PAGE_SIZE) /* 64K PTEs, 256KB */
41#define IOMMU_ORDER 6 /* 4096 * (1<<6) */
42
43static int viking_flush;
44/* viking.S */
45extern void viking_flush_page(unsigned long page);
46extern void viking_mxcc_flush_page(unsigned long page);
47
48/*
49 * Values precomputed according to CPU type.
50 */
51static unsigned int ioperm_noc; /* Consistent mapping iopte flags */
52static pgprot_t dvma_prot; /* Consistent mapping pte flags */
53
54#define IOPERM (IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID)
55#define MKIOPTE(pfn, perm) (((((pfn)<<8) & IOPTE_PAGE) | (perm)) & ~IOPTE_WAZ)
56
57static void __init sbus_iommu_init(struct platform_device *op)
58{
59 struct iommu_struct *iommu;
60 unsigned int impl, vers;
61 unsigned long *bitmap;
62 unsigned long control;
63 unsigned long base;
64 unsigned long tmp;
65
66 iommu = kmalloc(sizeof(struct iommu_struct), GFP_KERNEL);
67 if (!iommu) {
68 prom_printf("Unable to allocate iommu structure\n");
69 prom_halt();
70 }
71
72 iommu->regs = of_ioremap(&op->resource[0], 0, PAGE_SIZE * 3,
73 "iommu_regs");
74 if (!iommu->regs) {
75 prom_printf("Cannot map IOMMU registers\n");
76 prom_halt();
77 }
78
79 control = sbus_readl(&iommu->regs->control);
80 impl = (control & IOMMU_CTRL_IMPL) >> 28;
81 vers = (control & IOMMU_CTRL_VERS) >> 24;
82 control &= ~(IOMMU_CTRL_RNGE);
83 control |= (IOMMU_RNGE_256MB | IOMMU_CTRL_ENAB);
84 sbus_writel(control, &iommu->regs->control);
85
86 iommu_invalidate(iommu->regs);
87 iommu->start = IOMMU_START;
88 iommu->end = 0xffffffff;
89
90 /* Allocate IOMMU page table */
91 /* Stupid alignment constraints give me a headache.
92 We need 256K or 512K or 1M or 2M area aligned to
93 its size and current gfp will fortunately give
94 it to us. */
95 tmp = __get_free_pages(GFP_KERNEL, IOMMU_ORDER);
96 if (!tmp) {
97 prom_printf("Unable to allocate iommu table [0x%lx]\n",
98 IOMMU_NPTES * sizeof(iopte_t));
99 prom_halt();
100 }
101 iommu->page_table = (iopte_t *)tmp;
102
103 /* Initialize new table. */
104 memset(iommu->page_table, 0, IOMMU_NPTES*sizeof(iopte_t));
105 flush_cache_all();
106 flush_tlb_all();
107
108 base = __pa((unsigned long)iommu->page_table) >> 4;
109 sbus_writel(base, &iommu->regs->base);
110 iommu_invalidate(iommu->regs);
111
112 bitmap = kmalloc(IOMMU_NPTES>>3, GFP_KERNEL);
113 if (!bitmap) {
114 prom_printf("Unable to allocate iommu bitmap [%d]\n",
115 (int)(IOMMU_NPTES>>3));
116 prom_halt();
117 }
118 bit_map_init(&iommu->usemap, bitmap, IOMMU_NPTES);
119 /* To be coherent on HyperSparc, the page color of DVMA
120 * and physical addresses must match.
121 */
122 if (srmmu_modtype == HyperSparc)
123 iommu->usemap.num_colors = vac_cache_size >> PAGE_SHIFT;
124 else
125 iommu->usemap.num_colors = 1;
126
127 printk(KERN_INFO "IOMMU: impl %d vers %d table 0x%p[%d B] map [%d b]\n",
128 impl, vers, iommu->page_table,
129 (int)(IOMMU_NPTES*sizeof(iopte_t)), (int)IOMMU_NPTES);
130
131 op->dev.archdata.iommu = iommu;
132}
133
134static int __init iommu_init(void)
135{
136 struct device_node *dp;
137
138 for_each_node_by_name(dp, "iommu") {
139 struct platform_device *op = of_find_device_by_node(dp);
140
141 sbus_iommu_init(op);
142 of_propagate_archdata(op);
143 }
144
145 return 0;
146}
147
148subsys_initcall(iommu_init);
149
150/* Flush the iotlb entries to ram. */
151/* This could be better if we didn't have to flush whole pages. */
152static void iommu_flush_iotlb(iopte_t *iopte, unsigned int niopte)
153{
154 unsigned long start;
155 unsigned long end;
156
157 start = (unsigned long)iopte;
158 end = PAGE_ALIGN(start + niopte*sizeof(iopte_t));
159 start &= PAGE_MASK;
160 if (viking_mxcc_present) {
161 while(start < end) {
162 viking_mxcc_flush_page(start);
163 start += PAGE_SIZE;
164 }
165 } else if (viking_flush) {
166 while(start < end) {
167 viking_flush_page(start);
168 start += PAGE_SIZE;
169 }
170 } else {
171 while(start < end) {
172 __flush_page_to_ram(start);
173 start += PAGE_SIZE;
174 }
175 }
176}
177
178static dma_addr_t __sbus_iommu_map_page(struct device *dev, struct page *page,
179 unsigned long offset, size_t len, bool per_page_flush)
180{
181 struct iommu_struct *iommu = dev->archdata.iommu;
182 phys_addr_t paddr = page_to_phys(page) + offset;
183 unsigned long off = paddr & ~PAGE_MASK;
184 unsigned long npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
185 unsigned long pfn = __phys_to_pfn(paddr);
186 unsigned int busa, busa0;
187 iopte_t *iopte, *iopte0;
188 int ioptex, i;
189
190 /* XXX So what is maxphys for us and how do drivers know it? */
191 if (!len || len > 256 * 1024)
192 return DMA_MAPPING_ERROR;
193
194 /*
195 * We expect unmapped highmem pages to be not in the cache.
196 * XXX Is this a good assumption?
197 * XXX What if someone else unmaps it here and races us?
198 */
199 if (per_page_flush && !PageHighMem(page)) {
200 unsigned long vaddr, p;
201
202 vaddr = (unsigned long)page_address(page) + offset;
203 for (p = vaddr & PAGE_MASK; p < vaddr + len; p += PAGE_SIZE)
204 flush_page_for_dma(p);
205 }
206
207 /* page color = pfn of page */
208 ioptex = bit_map_string_get(&iommu->usemap, npages, pfn);
209 if (ioptex < 0)
210 panic("iommu out");
211 busa0 = iommu->start + (ioptex << PAGE_SHIFT);
212 iopte0 = &iommu->page_table[ioptex];
213
214 busa = busa0;
215 iopte = iopte0;
216 for (i = 0; i < npages; i++) {
217 iopte_val(*iopte) = MKIOPTE(pfn, IOPERM);
218 iommu_invalidate_page(iommu->regs, busa);
219 busa += PAGE_SIZE;
220 iopte++;
221 pfn++;
222 }
223
224 iommu_flush_iotlb(iopte0, npages);
225 return busa0 + off;
226}
227
228static dma_addr_t sbus_iommu_map_page_gflush(struct device *dev,
229 struct page *page, unsigned long offset, size_t len,
230 enum dma_data_direction dir, unsigned long attrs)
231{
232 flush_page_for_dma(0);
233 return __sbus_iommu_map_page(dev, page, offset, len, false);
234}
235
236static dma_addr_t sbus_iommu_map_page_pflush(struct device *dev,
237 struct page *page, unsigned long offset, size_t len,
238 enum dma_data_direction dir, unsigned long attrs)
239{
240 return __sbus_iommu_map_page(dev, page, offset, len, true);
241}
242
243static int __sbus_iommu_map_sg(struct device *dev, struct scatterlist *sgl,
244 int nents, enum dma_data_direction dir, unsigned long attrs,
245 bool per_page_flush)
246{
247 struct scatterlist *sg;
248 int j;
249
250 for_each_sg(sgl, sg, nents, j) {
251 sg->dma_address =__sbus_iommu_map_page(dev, sg_page(sg),
252 sg->offset, sg->length, per_page_flush);
253 if (sg->dma_address == DMA_MAPPING_ERROR)
254 return 0;
255 sg->dma_length = sg->length;
256 }
257
258 return nents;
259}
260
261static int sbus_iommu_map_sg_gflush(struct device *dev, struct scatterlist *sgl,
262 int nents, enum dma_data_direction dir, unsigned long attrs)
263{
264 flush_page_for_dma(0);
265 return __sbus_iommu_map_sg(dev, sgl, nents, dir, attrs, false);
266}
267
268static int sbus_iommu_map_sg_pflush(struct device *dev, struct scatterlist *sgl,
269 int nents, enum dma_data_direction dir, unsigned long attrs)
270{
271 return __sbus_iommu_map_sg(dev, sgl, nents, dir, attrs, true);
272}
273
274static void sbus_iommu_unmap_page(struct device *dev, dma_addr_t dma_addr,
275 size_t len, enum dma_data_direction dir, unsigned long attrs)
276{
277 struct iommu_struct *iommu = dev->archdata.iommu;
278 unsigned int busa = dma_addr & PAGE_MASK;
279 unsigned long off = dma_addr & ~PAGE_MASK;
280 unsigned int npages = (off + len + PAGE_SIZE-1) >> PAGE_SHIFT;
281 unsigned int ioptex = (busa - iommu->start) >> PAGE_SHIFT;
282 unsigned int i;
283
284 BUG_ON(busa < iommu->start);
285 for (i = 0; i < npages; i++) {
286 iopte_val(iommu->page_table[ioptex + i]) = 0;
287 iommu_invalidate_page(iommu->regs, busa);
288 busa += PAGE_SIZE;
289 }
290 bit_map_clear(&iommu->usemap, ioptex, npages);
291}
292
293static void sbus_iommu_unmap_sg(struct device *dev, struct scatterlist *sgl,
294 int nents, enum dma_data_direction dir, unsigned long attrs)
295{
296 struct scatterlist *sg;
297 int i;
298
299 for_each_sg(sgl, sg, nents, i) {
300 sbus_iommu_unmap_page(dev, sg->dma_address, sg->length, dir,
301 attrs);
302 sg->dma_address = 0x21212121;
303 }
304}
305
306#ifdef CONFIG_SBUS
307static void *sbus_iommu_alloc(struct device *dev, size_t len,
308 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
309{
310 struct iommu_struct *iommu = dev->archdata.iommu;
311 unsigned long va, addr, page, end, ret;
312 iopte_t *iopte = iommu->page_table;
313 iopte_t *first;
314 int ioptex;
315
316 /* XXX So what is maxphys for us and how do drivers know it? */
317 if (!len || len > 256 * 1024)
318 return NULL;
319
320 len = PAGE_ALIGN(len);
321 va = __get_free_pages(gfp | __GFP_ZERO, get_order(len));
322 if (va == 0)
323 return NULL;
324
325 addr = ret = sparc_dma_alloc_resource(dev, len);
326 if (!addr)
327 goto out_free_pages;
328
329 BUG_ON((va & ~PAGE_MASK) != 0);
330 BUG_ON((addr & ~PAGE_MASK) != 0);
331 BUG_ON((len & ~PAGE_MASK) != 0);
332
333 /* page color = physical address */
334 ioptex = bit_map_string_get(&iommu->usemap, len >> PAGE_SHIFT,
335 addr >> PAGE_SHIFT);
336 if (ioptex < 0)
337 panic("iommu out");
338
339 iopte += ioptex;
340 first = iopte;
341 end = addr + len;
342 while(addr < end) {
343 page = va;
344 {
345 pgd_t *pgdp;
346 pmd_t *pmdp;
347 pte_t *ptep;
348
349 if (viking_mxcc_present)
350 viking_mxcc_flush_page(page);
351 else if (viking_flush)
352 viking_flush_page(page);
353 else
354 __flush_page_to_ram(page);
355
356 pgdp = pgd_offset(&init_mm, addr);
357 pmdp = pmd_offset(pgdp, addr);
358 ptep = pte_offset_map(pmdp, addr);
359
360 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
361 }
362 iopte_val(*iopte++) =
363 MKIOPTE(page_to_pfn(virt_to_page(page)), ioperm_noc);
364 addr += PAGE_SIZE;
365 va += PAGE_SIZE;
366 }
367 /* P3: why do we need this?
368 *
369 * DAVEM: Because there are several aspects, none of which
370 * are handled by a single interface. Some cpus are
371 * completely not I/O DMA coherent, and some have
372 * virtually indexed caches. The driver DMA flushing
373 * methods handle the former case, but here during
374 * IOMMU page table modifications, and usage of non-cacheable
375 * cpu mappings of pages potentially in the cpu caches, we have
376 * to handle the latter case as well.
377 */
378 flush_cache_all();
379 iommu_flush_iotlb(first, len >> PAGE_SHIFT);
380 flush_tlb_all();
381 iommu_invalidate(iommu->regs);
382
383 *dma_handle = iommu->start + (ioptex << PAGE_SHIFT);
384 return (void *)ret;
385
386out_free_pages:
387 free_pages(va, get_order(len));
388 return NULL;
389}
390
391static void sbus_iommu_free(struct device *dev, size_t len, void *cpu_addr,
392 dma_addr_t busa, unsigned long attrs)
393{
394 struct iommu_struct *iommu = dev->archdata.iommu;
395 iopte_t *iopte = iommu->page_table;
396 struct page *page = virt_to_page(cpu_addr);
397 int ioptex = (busa - iommu->start) >> PAGE_SHIFT;
398 unsigned long end;
399
400 if (!sparc_dma_free_resource(cpu_addr, len))
401 return;
402
403 BUG_ON((busa & ~PAGE_MASK) != 0);
404 BUG_ON((len & ~PAGE_MASK) != 0);
405
406 iopte += ioptex;
407 end = busa + len;
408 while (busa < end) {
409 iopte_val(*iopte++) = 0;
410 busa += PAGE_SIZE;
411 }
412 flush_tlb_all();
413 iommu_invalidate(iommu->regs);
414 bit_map_clear(&iommu->usemap, ioptex, len >> PAGE_SHIFT);
415
416 __free_pages(page, get_order(len));
417}
418#endif
419
420static const struct dma_map_ops sbus_iommu_dma_gflush_ops = {
421#ifdef CONFIG_SBUS
422 .alloc = sbus_iommu_alloc,
423 .free = sbus_iommu_free,
424#endif
425 .map_page = sbus_iommu_map_page_gflush,
426 .unmap_page = sbus_iommu_unmap_page,
427 .map_sg = sbus_iommu_map_sg_gflush,
428 .unmap_sg = sbus_iommu_unmap_sg,
429};
430
431static const struct dma_map_ops sbus_iommu_dma_pflush_ops = {
432#ifdef CONFIG_SBUS
433 .alloc = sbus_iommu_alloc,
434 .free = sbus_iommu_free,
435#endif
436 .map_page = sbus_iommu_map_page_pflush,
437 .unmap_page = sbus_iommu_unmap_page,
438 .map_sg = sbus_iommu_map_sg_pflush,
439 .unmap_sg = sbus_iommu_unmap_sg,
440};
441
442void __init ld_mmu_iommu(void)
443{
444 if (flush_page_for_dma_global) {
445 /* flush_page_for_dma flushes everything, no matter of what page is it */
446 dma_ops = &sbus_iommu_dma_gflush_ops;
447 } else {
448 dma_ops = &sbus_iommu_dma_pflush_ops;
449 }
450
451 if (viking_mxcc_present || srmmu_modtype == HyperSparc) {
452 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
453 ioperm_noc = IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID;
454 } else {
455 dvma_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV);
456 ioperm_noc = IOPTE_WRITE | IOPTE_VALID;
457 }
458}