summaryrefslogtreecommitdiffstats
path: root/arch/sparc64/kernel/iommu.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sparc64/kernel/iommu.c')
-rw-r--r--arch/sparc64/kernel/iommu.c809
1 files changed, 809 insertions, 0 deletions
diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
new file mode 100644
index 00000000000..b35a62167e9
--- /dev/null
+++ b/arch/sparc64/kernel/iommu.c
@@ -0,0 +1,809 @@
+/* iommu.c: Generic sparc64 IOMMU support.
+ *
+ * Copyright (C) 1999, 2007 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1999, 2000 Jakub Jelinek (jakub@redhat.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+
+#ifdef CONFIG_PCI
+#include <linux/pci.h>
+#endif
+
+#include <asm/iommu.h>
+
+#include "iommu_common.h"
+
+#define STC_CTXMATCH_ADDR(STC, CTX) \
+ ((STC)->strbuf_ctxmatch_base + ((CTX) << 3))
+#define STC_FLUSHFLAG_INIT(STC) \
+ (*((STC)->strbuf_flushflag) = 0UL)
+#define STC_FLUSHFLAG_SET(STC) \
+ (*((STC)->strbuf_flushflag) != 0UL)
+
+#define iommu_read(__reg) \
+({ u64 __ret; \
+ __asm__ __volatile__("ldxa [%1] %2, %0" \
+ : "=r" (__ret) \
+ : "r" (__reg), "i" (ASI_PHYS_BYPASS_EC_E) \
+ : "memory"); \
+ __ret; \
+})
+#define iommu_write(__reg, __val) \
+ __asm__ __volatile__("stxa %0, [%1] %2" \
+ : /* no outputs */ \
+ : "r" (__val), "r" (__reg), \
+ "i" (ASI_PHYS_BYPASS_EC_E))
+
+/* Must be invoked under the IOMMU lock. */
+static void __iommu_flushall(struct iommu *iommu)
+{
+ if (iommu->iommu_flushinv) {
+ iommu_write(iommu->iommu_flushinv, ~(u64)0);
+ } else {
+ unsigned long tag;
+ int entry;
+
+ tag = iommu->iommu_tags;
+ for (entry = 0; entry < 16; entry++) {
+ iommu_write(tag, 0);
+ tag += 8;
+ }
+
+ /* Ensure completion of previous PIO writes. */
+ (void) iommu_read(iommu->write_complete_reg);
+ }
+}
+
+#define IOPTE_CONSISTENT(CTX) \
+ (IOPTE_VALID | IOPTE_CACHE | \
+ (((CTX) << 47) & IOPTE_CONTEXT))
+
+#define IOPTE_STREAMING(CTX) \
+ (IOPTE_CONSISTENT(CTX) | IOPTE_STBUF)
+
+/* Existing mappings are never marked invalid, instead they
+ * are pointed to a dummy page.
+ */
+#define IOPTE_IS_DUMMY(iommu, iopte) \
+ ((iopte_val(*iopte) & IOPTE_PAGE) == (iommu)->dummy_page_pa)
+
+static inline void iopte_make_dummy(struct iommu *iommu, iopte_t *iopte)
+{
+ unsigned long val = iopte_val(*iopte);
+
+ val &= ~IOPTE_PAGE;
+ val |= iommu->dummy_page_pa;
+
+ iopte_val(*iopte) = val;
+}
+
+/* Based largely upon the ppc64 iommu allocator. */
+static long arena_alloc(struct iommu *iommu, unsigned long npages)
+{
+ struct iommu_arena *arena = &iommu->arena;
+ unsigned long n, i, start, end, limit;
+ int pass;
+
+ limit = arena->limit;
+ start = arena->hint;
+ pass = 0;
+
+again:
+ n = find_next_zero_bit(arena->map, limit, start);
+ end = n + npages;
+ if (unlikely(end >= limit)) {
+ if (likely(pass < 1)) {
+ limit = start;
+ start = 0;
+ __iommu_flushall(iommu);
+ pass++;
+ goto again;
+ } else {
+ /* Scanned the whole thing, give up. */
+ return -1;
+ }
+ }
+
+ for (i = n; i < end; i++) {
+ if (test_bit(i, arena->map)) {
+ start = i + 1;
+ goto again;
+ }
+ }
+
+ for (i = n; i < end; i++)
+ __set_bit(i, arena->map);
+
+ arena->hint = end;
+
+ return n;
+}
+
+static void arena_free(struct iommu_arena *arena, unsigned long base, unsigned long npages)
+{
+ unsigned long i;
+
+ for (i = base; i < (base + npages); i++)
+ __clear_bit(i, arena->map);
+}
+
+int iommu_table_init(struct iommu *iommu, int tsbsize,
+ u32 dma_offset, u32 dma_addr_mask)
+{
+ unsigned long i, tsbbase, order, sz, num_tsb_entries;
+
+ num_tsb_entries = tsbsize / sizeof(iopte_t);
+
+ /* Setup initial software IOMMU state. */
+ spin_lock_init(&iommu->lock);
+ iommu->ctx_lowest_free = 1;
+ iommu->page_table_map_base = dma_offset;
+ iommu->dma_addr_mask = dma_addr_mask;
+
+ /* Allocate and initialize the free area map. */
+ sz = num_tsb_entries / 8;
+ sz = (sz + 7UL) & ~7UL;
+ iommu->arena.map = kzalloc(sz, GFP_KERNEL);
+ if (!iommu->arena.map) {
+ printk(KERN_ERR "IOMMU: Error, kmalloc(arena.map) failed.\n");
+ return -ENOMEM;
+ }
+ iommu->arena.limit = num_tsb_entries;
+
+ /* Allocate and initialize the dummy page which we
+ * set inactive IO PTEs to point to.
+ */
+ iommu->dummy_page = __get_free_pages(GFP_KERNEL, 0);
+ if (!iommu->dummy_page) {
+ printk(KERN_ERR "IOMMU: Error, gfp(dummy_page) failed.\n");
+ goto out_free_map;
+ }
+ memset((void *)iommu->dummy_page, 0, PAGE_SIZE);
+ iommu->dummy_page_pa = (unsigned long) __pa(iommu->dummy_page);
+
+ /* Now allocate and setup the IOMMU page table itself. */
+ order = get_order(tsbsize);
+ tsbbase = __get_free_pages(GFP_KERNEL, order);
+ if (!tsbbase) {
+ printk(KERN_ERR "IOMMU: Error, gfp(tsb) failed.\n");
+ goto out_free_dummy_page;
+ }
+ iommu->page_table = (iopte_t *)tsbbase;
+
+ for (i = 0; i < num_tsb_entries; i++)
+ iopte_make_dummy(iommu, &iommu->page_table[i]);
+
+ return 0;
+
+out_free_dummy_page:
+ free_page(iommu->dummy_page);
+ iommu->dummy_page = 0UL;
+
+out_free_map:
+ kfree(iommu->arena.map);
+ iommu->arena.map = NULL;
+
+ return -ENOMEM;
+}
+
+static inline iopte_t *alloc_npages(struct iommu *iommu, unsigned long npages)
+{
+ long entry;
+
+ entry = arena_alloc(iommu, npages);
+ if (unlikely(entry < 0))
+ return NULL;
+
+ return iommu->page_table + entry;
+}
+
+static inline void free_npages(struct iommu *iommu, dma_addr_t base, unsigned long npages)
+{
+ arena_free(&iommu->arena, base >> IO_PAGE_SHIFT, npages);
+}
+
+static int iommu_alloc_ctx(struct iommu *iommu)
+{
+ int lowest = iommu->ctx_lowest_free;
+ int sz = IOMMU_NUM_CTXS - lowest;
+ int n = find_next_zero_bit(iommu->ctx_bitmap, sz, lowest);
+
+ if (unlikely(n == sz)) {
+ n = find_next_zero_bit(iommu->ctx_bitmap, lowest, 1);
+ if (unlikely(n == lowest)) {
+ printk(KERN_WARNING "IOMMU: Ran out of contexts.\n");
+ n = 0;
+ }
+ }
+ if (n)
+ __set_bit(n, iommu->ctx_bitmap);
+
+ return n;
+}
+
+static inline void iommu_free_ctx(struct iommu *iommu, int ctx)
+{
+ if (likely(ctx)) {
+ __clear_bit(ctx, iommu->ctx_bitmap);
+ if (ctx < iommu->ctx_lowest_free)
+ iommu->ctx_lowest_free = ctx;
+ }
+}
+
+static void *dma_4u_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_addrp, gfp_t gfp)
+{
+ struct iommu *iommu;
+ iopte_t *iopte;
+ unsigned long flags, order, first_page;
+ void *ret;
+ int npages;
+
+ size = IO_PAGE_ALIGN(size);
+ order = get_order(size);
+ if (order >= 10)
+ return NULL;
+
+ first_page = __get_free_pages(gfp, order);
+ if (first_page == 0UL)
+ return NULL;
+ memset((char *)first_page, 0, PAGE_SIZE << order);
+
+ iommu = dev->archdata.iommu;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+ iopte = alloc_npages(iommu, size >> IO_PAGE_SHIFT);
+ spin_unlock_irqrestore(&iommu->lock, flags);
+
+ if (unlikely(iopte == NULL)) {
+ free_pages(first_page, order);
+ return NULL;
+ }
+
+ *dma_addrp = (iommu->page_table_map_base +
+ ((iopte - iommu->page_table) << IO_PAGE_SHIFT));
+ ret = (void *) first_page;
+ npages = size >> IO_PAGE_SHIFT;
+ first_page = __pa(first_page);
+ while (npages--) {
+ iopte_val(*iopte) = (IOPTE_CONSISTENT(0UL) |
+ IOPTE_WRITE |
+ (first_page & IOPTE_PAGE));
+ iopte++;
+ first_page += IO_PAGE_SIZE;
+ }
+
+ return ret;
+}
+
+static void dma_4u_free_coherent(struct device *dev, size_t size,
+ void *cpu, dma_addr_t dvma)
+{
+ struct iommu *iommu;
+ iopte_t *iopte;
+ unsigned long flags, order, npages;
+
+ npages = IO_PAGE_ALIGN(size) >> IO_PAGE_SHIFT;
+ iommu = dev->archdata.iommu;
+ iopte = iommu->page_table +
+ ((dvma - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
+
+ spin_lock_irqsave(&iommu->lock, flags);
+
+ free_npages(iommu, dvma - iommu->page_table_map_base, npages);
+
+ spin_unlock_irqrestore(&iommu->lock, flags);
+
+ order = get_order(size);
+ if (order < 10)
+ free_pages((unsigned long)cpu, order);
+}
+
+static dma_addr_t dma_4u_map_single(struct device *dev, void *ptr, size_t sz,
+ enum dma_data_direction direction)
+{
+ struct iommu *iommu;
+ struct strbuf *strbuf;
+ iopte_t *base;
+ unsigned long flags, npages, oaddr;
+ unsigned long i, base_paddr, ctx;
+ u32 bus_addr, ret;
+ unsigned long iopte_protection;
+
+ iommu = dev->archdata.iommu;
+ strbuf = dev->archdata.stc;
+
+ if (unlikely(direction == DMA_NONE))
+ goto bad_no_ctx;
+
+ oaddr = (unsigned long)ptr;
+ npages = IO_PAGE_ALIGN(oaddr + sz) - (oaddr & IO_PAGE_MASK);
+ npages >>= IO_PAGE_SHIFT;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+ base = alloc_npages(iommu, npages);
+ ctx = 0;
+ if (iommu->iommu_ctxflush)
+ ctx = iommu_alloc_ctx(iommu);
+ spin_unlock_irqrestore(&iommu->lock, flags);
+
+ if (unlikely(!base))
+ goto bad;
+
+ bus_addr = (iommu->page_table_map_base +
+ ((base - iommu->page_table) << IO_PAGE_SHIFT));
+ ret = bus_addr | (oaddr & ~IO_PAGE_MASK);
+ base_paddr = __pa(oaddr & IO_PAGE_MASK);
+ if (strbuf->strbuf_enabled)
+ iopte_protection = IOPTE_STREAMING(ctx);
+ else
+ iopte_protection = IOPTE_CONSISTENT(ctx);
+ if (direction != DMA_TO_DEVICE)
+ iopte_protection |= IOPTE_WRITE;
+
+ for (i = 0; i < npages; i++, base++, base_paddr += IO_PAGE_SIZE)
+ iopte_val(*base) = iopte_protection | base_paddr;
+
+ return ret;
+
+bad:
+ iommu_free_ctx(iommu, ctx);
+bad_no_ctx:
+ if (printk_ratelimit())
+ WARN_ON(1);
+ return DMA_ERROR_CODE;
+}
+
+static void strbuf_flush(struct strbuf *strbuf, struct iommu *iommu,
+ u32 vaddr, unsigned long ctx, unsigned long npages,
+ enum dma_data_direction direction)
+{
+ int limit;
+
+ if (strbuf->strbuf_ctxflush &&
+ iommu->iommu_ctxflush) {
+ unsigned long matchreg, flushreg;
+ u64 val;
+
+ flushreg = strbuf->strbuf_ctxflush;
+ matchreg = STC_CTXMATCH_ADDR(strbuf, ctx);
+
+ iommu_write(flushreg, ctx);
+ val = iommu_read(matchreg);
+ val &= 0xffff;
+ if (!val)
+ goto do_flush_sync;
+
+ while (val) {
+ if (val & 0x1)
+ iommu_write(flushreg, ctx);
+ val >>= 1;
+ }
+ val = iommu_read(matchreg);
+ if (unlikely(val)) {
+ printk(KERN_WARNING "strbuf_flush: ctx flush "
+ "timeout matchreg[%lx] ctx[%lx]\n",
+ val, ctx);
+ goto do_page_flush;
+ }
+ } else {
+ unsigned long i;
+
+ do_page_flush:
+ for (i = 0; i < npages; i++, vaddr += IO_PAGE_SIZE)
+ iommu_write(strbuf->strbuf_pflush, vaddr);
+ }
+
+do_flush_sync:
+ /* If the device could not have possibly put dirty data into
+ * the streaming cache, no flush-flag synchronization needs
+ * to be performed.
+ */
+ if (direction == DMA_TO_DEVICE)
+ return;
+
+ STC_FLUSHFLAG_INIT(strbuf);
+ iommu_write(strbuf->strbuf_fsync, strbuf->strbuf_flushflag_pa);
+ (void) iommu_read(iommu->write_complete_reg);
+
+ limit = 100000;
+ while (!STC_FLUSHFLAG_SET(strbuf)) {
+ limit--;
+ if (!limit)
+ break;
+ udelay(1);
+ rmb();
+ }
+ if (!limit)
+ printk(KERN_WARNING "strbuf_flush: flushflag timeout "
+ "vaddr[%08x] ctx[%lx] npages[%ld]\n",
+ vaddr, ctx, npages);
+}
+
+static void dma_4u_unmap_single(struct device *dev, dma_addr_t bus_addr,
+ size_t sz, enum dma_data_direction direction)
+{
+ struct iommu *iommu;
+ struct strbuf *strbuf;
+ iopte_t *base;
+ unsigned long flags, npages, ctx, i;
+
+ if (unlikely(direction == DMA_NONE)) {
+ if (printk_ratelimit())
+ WARN_ON(1);
+ return;
+ }
+
+ iommu = dev->archdata.iommu;
+ strbuf = dev->archdata.stc;
+
+ npages = IO_PAGE_ALIGN(bus_addr + sz) - (bus_addr & IO_PAGE_MASK);
+ npages >>= IO_PAGE_SHIFT;
+ base = iommu->page_table +
+ ((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
+ bus_addr &= IO_PAGE_MASK;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+
+ /* Record the context, if any. */
+ ctx = 0;
+ if (iommu->iommu_ctxflush)
+ ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL;
+
+ /* Step 1: Kick data out of streaming buffers if necessary. */
+ if (strbuf->strbuf_enabled)
+ strbuf_flush(strbuf, iommu, bus_addr, ctx,
+ npages, direction);
+
+ /* Step 2: Clear out TSB entries. */
+ for (i = 0; i < npages; i++)
+ iopte_make_dummy(iommu, base + i);
+
+ free_npages(iommu, bus_addr - iommu->page_table_map_base, npages);
+
+ iommu_free_ctx(iommu, ctx);
+
+ spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
+#define SG_ENT_PHYS_ADDRESS(SG) \
+ (__pa(page_address((SG)->page)) + (SG)->offset)
+
+static inline void fill_sg(iopte_t *iopte, struct scatterlist *sg,
+ int nused, int nelems,
+ unsigned long iopte_protection)
+{
+ struct scatterlist *dma_sg = sg;
+ struct scatterlist *sg_end = sg + nelems;
+ int i;
+
+ for (i = 0; i < nused; i++) {
+ unsigned long pteval = ~0UL;
+ u32 dma_npages;
+
+ dma_npages = ((dma_sg->dma_address & (IO_PAGE_SIZE - 1UL)) +
+ dma_sg->dma_length +
+ ((IO_PAGE_SIZE - 1UL))) >> IO_PAGE_SHIFT;
+ do {
+ unsigned long offset;
+ signed int len;
+
+ /* If we are here, we know we have at least one
+ * more page to map. So walk forward until we
+ * hit a page crossing, and begin creating new
+ * mappings from that spot.
+ */
+ for (;;) {
+ unsigned long tmp;
+
+ tmp = SG_ENT_PHYS_ADDRESS(sg);
+ len = sg->length;
+ if (((tmp ^ pteval) >> IO_PAGE_SHIFT) != 0UL) {
+ pteval = tmp & IO_PAGE_MASK;
+ offset = tmp & (IO_PAGE_SIZE - 1UL);
+ break;
+ }
+ if (((tmp ^ (tmp + len - 1UL)) >> IO_PAGE_SHIFT) != 0UL) {
+ pteval = (tmp + IO_PAGE_SIZE) & IO_PAGE_MASK;
+ offset = 0UL;
+ len -= (IO_PAGE_SIZE - (tmp & (IO_PAGE_SIZE - 1UL)));
+ break;
+ }
+ sg++;
+ }
+
+ pteval = iopte_protection | (pteval & IOPTE_PAGE);
+ while (len > 0) {
+ *iopte++ = __iopte(pteval);
+ pteval += IO_PAGE_SIZE;
+ len -= (IO_PAGE_SIZE - offset);
+ offset = 0;
+ dma_npages--;
+ }
+
+ pteval = (pteval & IOPTE_PAGE) + len;
+ sg++;
+
+ /* Skip over any tail mappings we've fully mapped,
+ * adjusting pteval along the way. Stop when we
+ * detect a page crossing event.
+ */
+ while (sg < sg_end &&
+ (pteval << (64 - IO_PAGE_SHIFT)) != 0UL &&
+ (pteval == SG_ENT_PHYS_ADDRESS(sg)) &&
+ ((pteval ^
+ (SG_ENT_PHYS_ADDRESS(sg) + sg->length - 1UL)) >> IO_PAGE_SHIFT) == 0UL) {
+ pteval += sg->length;
+ sg++;
+ }
+ if ((pteval << (64 - IO_PAGE_SHIFT)) == 0UL)
+ pteval = ~0UL;
+ } while (dma_npages != 0);
+ dma_sg++;
+ }
+}
+
+static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist,
+ int nelems, enum dma_data_direction direction)
+{
+ struct iommu *iommu;
+ struct strbuf *strbuf;
+ unsigned long flags, ctx, npages, iopte_protection;
+ iopte_t *base;
+ u32 dma_base;
+ struct scatterlist *sgtmp;
+ int used;
+
+ /* Fast path single entry scatterlists. */
+ if (nelems == 1) {
+ sglist->dma_address =
+ dma_4u_map_single(dev,
+ (page_address(sglist->page) +
+ sglist->offset),
+ sglist->length, direction);
+ if (unlikely(sglist->dma_address == DMA_ERROR_CODE))
+ return 0;
+ sglist->dma_length = sglist->length;
+ return 1;
+ }
+
+ iommu = dev->archdata.iommu;
+ strbuf = dev->archdata.stc;
+
+ if (unlikely(direction == DMA_NONE))
+ goto bad_no_ctx;
+
+ /* Step 1: Prepare scatter list. */
+
+ npages = prepare_sg(sglist, nelems);
+
+ /* Step 2: Allocate a cluster and context, if necessary. */
+
+ spin_lock_irqsave(&iommu->lock, flags);
+
+ base = alloc_npages(iommu, npages);
+ ctx = 0;
+ if (iommu->iommu_ctxflush)
+ ctx = iommu_alloc_ctx(iommu);
+
+ spin_unlock_irqrestore(&iommu->lock, flags);
+
+ if (base == NULL)
+ goto bad;
+
+ dma_base = iommu->page_table_map_base +
+ ((base - iommu->page_table) << IO_PAGE_SHIFT);
+
+ /* Step 3: Normalize DMA addresses. */
+ used = nelems;
+
+ sgtmp = sglist;
+ while (used && sgtmp->dma_length) {
+ sgtmp->dma_address += dma_base;
+ sgtmp++;
+ used--;
+ }
+ used = nelems - used;
+
+ /* Step 4: Create the mappings. */
+ if (strbuf->strbuf_enabled)
+ iopte_protection = IOPTE_STREAMING(ctx);
+ else
+ iopte_protection = IOPTE_CONSISTENT(ctx);
+ if (direction != DMA_TO_DEVICE)
+ iopte_protection |= IOPTE_WRITE;
+
+ fill_sg(base, sglist, used, nelems, iopte_protection);
+
+#ifdef VERIFY_SG
+ verify_sglist(sglist, nelems, base, npages);
+#endif
+
+ return used;
+
+bad:
+ iommu_free_ctx(iommu, ctx);
+bad_no_ctx:
+ if (printk_ratelimit())
+ WARN_ON(1);
+ return 0;
+}
+
+static void dma_4u_unmap_sg(struct device *dev, struct scatterlist *sglist,
+ int nelems, enum dma_data_direction direction)
+{
+ struct iommu *iommu;
+ struct strbuf *strbuf;
+ iopte_t *base;
+ unsigned long flags, ctx, i, npages;
+ u32 bus_addr;
+
+ if (unlikely(direction == DMA_NONE)) {
+ if (printk_ratelimit())
+ WARN_ON(1);
+ }
+
+ iommu = dev->archdata.iommu;
+ strbuf = dev->archdata.stc;
+
+ bus_addr = sglist->dma_address & IO_PAGE_MASK;
+
+ for (i = 1; i < nelems; i++)
+ if (sglist[i].dma_length == 0)
+ break;
+ i--;
+ npages = (IO_PAGE_ALIGN(sglist[i].dma_address + sglist[i].dma_length) -
+ bus_addr) >> IO_PAGE_SHIFT;
+
+ base = iommu->page_table +
+ ((bus_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
+
+ spin_lock_irqsave(&iommu->lock, flags);
+
+ /* Record the context, if any. */
+ ctx = 0;
+ if (iommu->iommu_ctxflush)
+ ctx = (iopte_val(*base) & IOPTE_CONTEXT) >> 47UL;
+
+ /* Step 1: Kick data out of streaming buffers if necessary. */
+ if (strbuf->strbuf_enabled)
+ strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
+
+ /* Step 2: Clear out the TSB entries. */
+ for (i = 0; i < npages; i++)
+ iopte_make_dummy(iommu, base + i);
+
+ free_npages(iommu, bus_addr - iommu->page_table_map_base, npages);
+
+ iommu_free_ctx(iommu, ctx);
+
+ spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
+static void dma_4u_sync_single_for_cpu(struct device *dev,
+ dma_addr_t bus_addr, size_t sz,
+ enum dma_data_direction direction)
+{
+ struct iommu *iommu;
+ struct strbuf *strbuf;
+ unsigned long flags, ctx, npages;
+
+ iommu = dev->archdata.iommu;
+ strbuf = dev->archdata.stc;
+
+ if (!strbuf->strbuf_enabled)
+ return;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+
+ npages = IO_PAGE_ALIGN(bus_addr + sz) - (bus_addr & IO_PAGE_MASK);
+ npages >>= IO_PAGE_SHIFT;
+ bus_addr &= IO_PAGE_MASK;
+
+ /* Step 1: Record the context, if any. */
+ ctx = 0;
+ if (iommu->iommu_ctxflush &&
+ strbuf->strbuf_ctxflush) {
+ iopte_t *iopte;
+
+ iopte = iommu->page_table +
+ ((bus_addr - iommu->page_table_map_base)>>IO_PAGE_SHIFT);
+ ctx = (iopte_val(*iopte) & IOPTE_CONTEXT) >> 47UL;
+ }
+
+ /* Step 2: Kick data out of streaming buffers. */
+ strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
+
+ spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
+static void dma_4u_sync_sg_for_cpu(struct device *dev,
+ struct scatterlist *sglist, int nelems,
+ enum dma_data_direction direction)
+{
+ struct iommu *iommu;
+ struct strbuf *strbuf;
+ unsigned long flags, ctx, npages, i;
+ u32 bus_addr;
+
+ iommu = dev->archdata.iommu;
+ strbuf = dev->archdata.stc;
+
+ if (!strbuf->strbuf_enabled)
+ return;
+
+ spin_lock_irqsave(&iommu->lock, flags);
+
+ /* Step 1: Record the context, if any. */
+ ctx = 0;
+ if (iommu->iommu_ctxflush &&
+ strbuf->strbuf_ctxflush) {
+ iopte_t *iopte;
+
+ iopte = iommu->page_table +
+ ((sglist[0].dma_address - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
+ ctx = (iopte_val(*iopte) & IOPTE_CONTEXT) >> 47UL;
+ }
+
+ /* Step 2: Kick data out of streaming buffers. */
+ bus_addr = sglist[0].dma_address & IO_PAGE_MASK;
+ for(i = 1; i < nelems; i++)
+ if (!sglist[i].dma_length)
+ break;
+ i--;
+ npages = (IO_PAGE_ALIGN(sglist[i].dma_address + sglist[i].dma_length)
+ - bus_addr) >> IO_PAGE_SHIFT;
+ strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
+
+ spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
+const struct dma_ops sun4u_dma_ops = {
+ .alloc_coherent = dma_4u_alloc_coherent,
+ .free_coherent = dma_4u_free_coherent,
+ .map_single = dma_4u_map_single,
+ .unmap_single = dma_4u_unmap_single,
+ .map_sg = dma_4u_map_sg,
+ .unmap_sg = dma_4u_unmap_sg,
+ .sync_single_for_cpu = dma_4u_sync_single_for_cpu,
+ .sync_sg_for_cpu = dma_4u_sync_sg_for_cpu,
+};
+
+const struct dma_ops *dma_ops = &sun4u_dma_ops;
+EXPORT_SYMBOL(dma_ops);
+
+int dma_supported(struct device *dev, u64 device_mask)
+{
+ struct iommu *iommu = dev->archdata.iommu;
+ u64 dma_addr_mask = iommu->dma_addr_mask;
+
+ if (device_mask >= (1UL << 32UL))
+ return 0;
+
+ if ((device_mask & dma_addr_mask) == dma_addr_mask)
+ return 1;
+
+#ifdef CONFIG_PCI
+ if (dev->bus == &pci_bus_type)
+ return pci_dma_supported(to_pci_dev(dev), device_mask);
+#endif
+
+ return 0;
+}
+EXPORT_SYMBOL(dma_supported);
+
+int dma_set_mask(struct device *dev, u64 dma_mask)
+{
+#ifdef CONFIG_PCI
+ if (dev->bus == &pci_bus_type)
+ return pci_set_dma_mask(to_pci_dev(dev), dma_mask);
+#endif
+ return -EINVAL;
+}
+EXPORT_SYMBOL(dma_set_mask);