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v6.2
  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}
v3.5.6
 
  1/*
  2 * iommu.c:  IOMMU specific routines for memory management.
  3 *
  4 * Copyright (C) 1995 David S. Miller  (davem@caip.rutgers.edu)
  5 * Copyright (C) 1995,2002 Pete Zaitcev     (zaitcev@yahoo.com)
  6 * Copyright (C) 1996 Eddie C. Dost    (ecd@skynet.be)
  7 * Copyright (C) 1997,1998 Jakub Jelinek    (jj@sunsite.mff.cuni.cz)
  8 */
  9 
 10#include <linux/kernel.h>
 11#include <linux/init.h>
 12#include <linux/mm.h>
 13#include <linux/slab.h>
 14#include <linux/highmem.h>	/* pte_offset_map => kmap_atomic */
 15#include <linux/scatterlist.h>
 16#include <linux/of.h>
 17#include <linux/of_device.h>
 18
 19#include <asm/pgalloc.h>
 20#include <asm/pgtable.h>
 21#include <asm/io.h>
 22#include <asm/mxcc.h>
 23#include <asm/mbus.h>
 24#include <asm/cacheflush.h>
 25#include <asm/tlbflush.h>
 26#include <asm/bitext.h>
 27#include <asm/iommu.h>
 28#include <asm/dma.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, 265KB */
 38#define IOMMU_ORDER	6				/* 4096 * (1<<6) */
 39
 40/* srmmu.c */
 41extern int viking_mxcc_present;
 42extern int flush_page_for_dma_global;
 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 tmp;
 63
 64	iommu = kmalloc(sizeof(struct iommu_struct), GFP_KERNEL);
 65	if (!iommu) {
 66		prom_printf("Unable to allocate iommu structure\n");
 67		prom_halt();
 68	}
 69
 70	iommu->regs = of_ioremap(&op->resource[0], 0, PAGE_SIZE * 3,
 71				 "iommu_regs");
 72	if (!iommu->regs) {
 73		prom_printf("Cannot map IOMMU registers\n");
 74		prom_halt();
 75	}
 76	impl = (iommu->regs->control & IOMMU_CTRL_IMPL) >> 28;
 77	vers = (iommu->regs->control & IOMMU_CTRL_VERS) >> 24;
 78	tmp = iommu->regs->control;
 79	tmp &= ~(IOMMU_CTRL_RNGE);
 80	tmp |= (IOMMU_RNGE_256MB | IOMMU_CTRL_ENAB);
 81	iommu->regs->control = tmp;
 
 
 82	iommu_invalidate(iommu->regs);
 83	iommu->start = IOMMU_START;
 84	iommu->end = 0xffffffff;
 85
 86	/* Allocate IOMMU page table */
 87	/* Stupid alignment constraints give me a headache. 
 88	   We need 256K or 512K or 1M or 2M area aligned to
 89           its size and current gfp will fortunately give
 90           it to us. */
 91        tmp = __get_free_pages(GFP_KERNEL, IOMMU_ORDER);
 92	if (!tmp) {
 93		prom_printf("Unable to allocate iommu table [0x%08x]\n",
 94			    IOMMU_NPTES*sizeof(iopte_t));
 95		prom_halt();
 96	}
 97	iommu->page_table = (iopte_t *)tmp;
 98
 99	/* Initialize new table. */
100	memset(iommu->page_table, 0, IOMMU_NPTES*sizeof(iopte_t));
101	flush_cache_all();
102	flush_tlb_all();
103	iommu->regs->base = __pa((unsigned long) iommu->page_table) >> 4;
 
 
104	iommu_invalidate(iommu->regs);
105
106	bitmap = kmalloc(IOMMU_NPTES>>3, GFP_KERNEL);
107	if (!bitmap) {
108		prom_printf("Unable to allocate iommu bitmap [%d]\n",
109			    (int)(IOMMU_NPTES>>3));
110		prom_halt();
111	}
112	bit_map_init(&iommu->usemap, bitmap, IOMMU_NPTES);
113	/* To be coherent on HyperSparc, the page color of DVMA
114	 * and physical addresses must match.
115	 */
116	if (srmmu_modtype == HyperSparc)
117		iommu->usemap.num_colors = vac_cache_size >> PAGE_SHIFT;
118	else
119		iommu->usemap.num_colors = 1;
120
121	printk(KERN_INFO "IOMMU: impl %d vers %d table 0x%p[%d B] map [%d b]\n",
122	       impl, vers, iommu->page_table,
123	       (int)(IOMMU_NPTES*sizeof(iopte_t)), (int)IOMMU_NPTES);
124
125	op->dev.archdata.iommu = iommu;
 
 
 
 
 
126}
127
128static int __init iommu_init(void)
129{
130	struct device_node *dp;
131
132	for_each_node_by_name(dp, "iommu") {
133		struct platform_device *op = of_find_device_by_node(dp);
134
135		sbus_iommu_init(op);
136		of_propagate_archdata(op);
137	}
138
139	return 0;
140}
141
142subsys_initcall(iommu_init);
143
144/* Flush the iotlb entries to ram. */
145/* This could be better if we didn't have to flush whole pages. */
146static void iommu_flush_iotlb(iopte_t *iopte, unsigned int niopte)
147{
148	unsigned long start;
149	unsigned long end;
150
151	start = (unsigned long)iopte;
152	end = PAGE_ALIGN(start + niopte*sizeof(iopte_t));
153	start &= PAGE_MASK;
154	if (viking_mxcc_present) {
155		while(start < end) {
156			viking_mxcc_flush_page(start);
157			start += PAGE_SIZE;
158		}
159	} else if (viking_flush) {
160		while(start < end) {
161			viking_flush_page(start);
162			start += PAGE_SIZE;
163		}
164	} else {
165		while(start < end) {
166			__flush_page_to_ram(start);
167			start += PAGE_SIZE;
168		}
169	}
170}
171
172static u32 iommu_get_one(struct device *dev, struct page *page, int npages)
 
173{
174	struct iommu_struct *iommu = dev->archdata.iommu;
175	int ioptex;
 
 
 
 
176	iopte_t *iopte, *iopte0;
177	unsigned int busa, busa0;
178	int i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
179
180	/* page color = pfn of page */
181	ioptex = bit_map_string_get(&iommu->usemap, npages, page_to_pfn(page));
182	if (ioptex < 0)
183		panic("iommu out");
184	busa0 = iommu->start + (ioptex << PAGE_SHIFT);
185	iopte0 = &iommu->page_table[ioptex];
186
187	busa = busa0;
188	iopte = iopte0;
189	for (i = 0; i < npages; i++) {
190		iopte_val(*iopte) = MKIOPTE(page_to_pfn(page), IOPERM);
191		iommu_invalidate_page(iommu->regs, busa);
192		busa += PAGE_SIZE;
193		iopte++;
194		page++;
195	}
196
197	iommu_flush_iotlb(iopte0, npages);
198
199	return busa0;
200}
201
202static u32 iommu_get_scsi_one(struct device *dev, char *vaddr, unsigned int len)
 
 
203{
204	unsigned long off;
205	int npages;
206	struct page *page;
207	u32 busa;
208
209	off = (unsigned long)vaddr & ~PAGE_MASK;
210	npages = (off + len + PAGE_SIZE-1) >> PAGE_SHIFT;
211	page = virt_to_page((unsigned long)vaddr & PAGE_MASK);
212	busa = iommu_get_one(dev, page, npages);
213	return busa + off;
214}
215
216static __u32 iommu_get_scsi_one_gflush(struct device *dev, char *vaddr, unsigned long len)
 
 
217{
218	flush_page_for_dma(0);
219	return iommu_get_scsi_one(dev, vaddr, len);
220}
221
222static __u32 iommu_get_scsi_one_pflush(struct device *dev, char *vaddr, unsigned long len)
 
 
223{
224	unsigned long page = ((unsigned long) vaddr) & PAGE_MASK;
 
225
226	while(page < ((unsigned long)(vaddr + len))) {
227		flush_page_for_dma(page);
228		page += PAGE_SIZE;
 
 
 
229	}
230	return iommu_get_scsi_one(dev, vaddr, len);
 
231}
232
233static void iommu_get_scsi_sgl_gflush(struct device *dev, struct scatterlist *sg, int sz)
 
234{
235	int n;
236
237	flush_page_for_dma(0);
238	while (sz != 0) {
239		--sz;
240		n = (sg->length + sg->offset + PAGE_SIZE-1) >> PAGE_SHIFT;
241		sg->dma_address = iommu_get_one(dev, sg_page(sg), n) + sg->offset;
242		sg->dma_length = sg->length;
243		sg = sg_next(sg);
244	}
245}
246
247static void iommu_get_scsi_sgl_pflush(struct device *dev, struct scatterlist *sg, int sz)
 
248{
249	unsigned long page, oldpage = 0;
250	int n, i;
251
252	while(sz != 0) {
253		--sz;
254
255		n = (sg->length + sg->offset + PAGE_SIZE-1) >> PAGE_SHIFT;
256
257		/*
258		 * We expect unmapped highmem pages to be not in the cache.
259		 * XXX Is this a good assumption?
260		 * XXX What if someone else unmaps it here and races us?
261		 */
262		if ((page = (unsigned long) page_address(sg_page(sg))) != 0) {
263			for (i = 0; i < n; i++) {
264				if (page != oldpage) {	/* Already flushed? */
265					flush_page_for_dma(page);
266					oldpage = page;
267				}
268				page += PAGE_SIZE;
269			}
270		}
271
272		sg->dma_address = iommu_get_one(dev, sg_page(sg), n) + sg->offset;
273		sg->dma_length = sg->length;
274		sg = sg_next(sg);
275	}
276}
277
278static void iommu_release_one(struct device *dev, u32 busa, int npages)
 
279{
280	struct iommu_struct *iommu = dev->archdata.iommu;
281	int ioptex;
282	int i;
 
 
 
283
284	BUG_ON(busa < iommu->start);
285	ioptex = (busa - iommu->start) >> PAGE_SHIFT;
286	for (i = 0; i < npages; i++) {
287		iopte_val(iommu->page_table[ioptex + i]) = 0;
288		iommu_invalidate_page(iommu->regs, busa);
289		busa += PAGE_SIZE;
290	}
291	bit_map_clear(&iommu->usemap, ioptex, npages);
292}
293
294static void iommu_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len)
 
295{
296	unsigned long off;
297	int npages;
298
299	off = vaddr & ~PAGE_MASK;
300	npages = (off + len + PAGE_SIZE-1) >> PAGE_SHIFT;
301	iommu_release_one(dev, vaddr & PAGE_MASK, npages);
302}
303
304static void iommu_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
305{
306	int n;
307
308	while(sz != 0) {
309		--sz;
310
311		n = (sg->length + sg->offset + PAGE_SIZE-1) >> PAGE_SHIFT;
312		iommu_release_one(dev, sg->dma_address & PAGE_MASK, n);
 
313		sg->dma_address = 0x21212121;
314		sg = sg_next(sg);
315	}
316}
317
318#ifdef CONFIG_SBUS
319static int iommu_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va,
320			      unsigned long addr, int len)
321{
322	struct iommu_struct *iommu = dev->archdata.iommu;
323	unsigned long page, end;
324	iopte_t *iopte = iommu->page_table;
325	iopte_t *first;
326	int ioptex;
327
 
 
 
 
 
 
 
 
 
 
 
 
 
328	BUG_ON((va & ~PAGE_MASK) != 0);
329	BUG_ON((addr & ~PAGE_MASK) != 0);
330	BUG_ON((len & ~PAGE_MASK) != 0);
331
332	/* page color = physical address */
333	ioptex = bit_map_string_get(&iommu->usemap, len >> PAGE_SHIFT,
334		addr >> PAGE_SHIFT);
335	if (ioptex < 0)
336		panic("iommu out");
337
338	iopte += ioptex;
339	first = iopte;
340	end = addr + len;
341	while(addr < end) {
342		page = va;
343		{
344			pgd_t *pgdp;
345			pmd_t *pmdp;
346			pte_t *ptep;
347
348			if (viking_mxcc_present)
349				viking_mxcc_flush_page(page);
350			else if (viking_flush)
351				viking_flush_page(page);
352			else
353				__flush_page_to_ram(page);
354
355			pgdp = pgd_offset(&init_mm, addr);
356			pmdp = pmd_offset(pgdp, addr);
357			ptep = pte_offset_map(pmdp, addr);
358
359			set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
360		}
361		iopte_val(*iopte++) =
362		    MKIOPTE(page_to_pfn(virt_to_page(page)), ioperm_noc);
363		addr += PAGE_SIZE;
364		va += PAGE_SIZE;
365	}
366	/* P3: why do we need this?
367	 *
368	 * DAVEM: Because there are several aspects, none of which
369	 *        are handled by a single interface.  Some cpus are
370	 *        completely not I/O DMA coherent, and some have
371	 *        virtually indexed caches.  The driver DMA flushing
372	 *        methods handle the former case, but here during
373	 *        IOMMU page table modifications, and usage of non-cacheable
374	 *        cpu mappings of pages potentially in the cpu caches, we have
375	 *        to handle the latter case as well.
376	 */
377	flush_cache_all();
378	iommu_flush_iotlb(first, len >> PAGE_SHIFT);
379	flush_tlb_all();
380	iommu_invalidate(iommu->regs);
381
382	*pba = iommu->start + (ioptex << PAGE_SHIFT);
383	return 0;
 
 
 
 
384}
385
386static void iommu_unmap_dma_area(struct device *dev, unsigned long busa, int len)
 
387{
388	struct iommu_struct *iommu = dev->archdata.iommu;
389	iopte_t *iopte = iommu->page_table;
 
 
390	unsigned long end;
391	int ioptex = (busa - iommu->start) >> PAGE_SHIFT;
 
 
392
393	BUG_ON((busa & ~PAGE_MASK) != 0);
394	BUG_ON((len & ~PAGE_MASK) != 0);
395
396	iopte += ioptex;
397	end = busa + len;
398	while (busa < end) {
399		iopte_val(*iopte++) = 0;
400		busa += PAGE_SIZE;
401	}
402	flush_tlb_all();
403	iommu_invalidate(iommu->regs);
404	bit_map_clear(&iommu->usemap, ioptex, len >> PAGE_SHIFT);
 
 
405}
406#endif
407
408static const struct sparc32_dma_ops iommu_dma_gflush_ops = {
409	.get_scsi_one		= iommu_get_scsi_one_gflush,
410	.get_scsi_sgl		= iommu_get_scsi_sgl_gflush,
411	.release_scsi_one	= iommu_release_scsi_one,
412	.release_scsi_sgl	= iommu_release_scsi_sgl,
413#ifdef CONFIG_SBUS
414	.map_dma_area		= iommu_map_dma_area,
415	.unmap_dma_area		= iommu_unmap_dma_area,
416#endif
 
 
 
 
417};
418
419static const struct sparc32_dma_ops iommu_dma_pflush_ops = {
420	.get_scsi_one		= iommu_get_scsi_one_pflush,
421	.get_scsi_sgl		= iommu_get_scsi_sgl_pflush,
422	.release_scsi_one	= iommu_release_scsi_one,
423	.release_scsi_sgl	= iommu_release_scsi_sgl,
424#ifdef CONFIG_SBUS
425	.map_dma_area		= iommu_map_dma_area,
426	.unmap_dma_area		= iommu_unmap_dma_area,
427#endif
 
 
 
 
428};
429
430void __init ld_mmu_iommu(void)
431{
432	if (flush_page_for_dma_global) {
433		/* flush_page_for_dma flushes everything, no matter of what page is it */
434		sparc32_dma_ops = &iommu_dma_gflush_ops;
435	} else {
436		sparc32_dma_ops = &iommu_dma_pflush_ops;
437	}
438
439	if (viking_mxcc_present || srmmu_modtype == HyperSparc) {
440		dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
441		ioperm_noc = IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID;
442	} else {
443		dvma_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV);
444		ioperm_noc = IOPTE_WRITE | IOPTE_VALID;
445	}
446}