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path: root/arch/sparc64/kernel/pci_iommu.c
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Diffstat (limited to 'arch/sparc64/kernel/pci_iommu.c')
-rw-r--r--arch/sparc64/kernel/pci_iommu.c88
1 files changed, 68 insertions, 20 deletions
diff --git a/arch/sparc64/kernel/pci_iommu.c b/arch/sparc64/kernel/pci_iommu.c
index 33ca56c90da2..2803bc7c2c79 100644
--- a/arch/sparc64/kernel/pci_iommu.c
+++ b/arch/sparc64/kernel/pci_iommu.c
@@ -196,6 +196,34 @@ static iopte_t *alloc_consistent_cluster(struct pci_iommu *iommu, unsigned long
return NULL;
}
+static int iommu_alloc_ctx(struct pci_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 pci_iommu *iommu, int ctx)
+{
+ if (likely(ctx)) {
+ __clear_bit(ctx, iommu->ctx_bitmap);
+ if (ctx < iommu->ctx_lowest_free)
+ iommu->ctx_lowest_free = ctx;
+ }
+}
+
/* Allocate and map kernel buffer of size SIZE using consistent mode
* DMA for PCI device PDEV. Return non-NULL cpu-side address if
* successful and set *DMA_ADDRP to the PCI side dma address.
@@ -236,7 +264,7 @@ void *pci_alloc_consistent(struct pci_dev *pdev, size_t size, dma_addr_t *dma_ad
npages = size >> IO_PAGE_SHIFT;
ctx = 0;
if (iommu->iommu_ctxflush)
- ctx = iommu->iommu_cur_ctx++;
+ ctx = iommu_alloc_ctx(iommu);
first_page = __pa(first_page);
while (npages--) {
iopte_val(*iopte) = (IOPTE_CONSISTENT(ctx) |
@@ -317,6 +345,8 @@ void pci_free_consistent(struct pci_dev *pdev, size_t size, void *cpu, dma_addr_
}
}
+ iommu_free_ctx(iommu, ctx);
+
spin_unlock_irqrestore(&iommu->lock, flags);
order = get_order(size);
@@ -360,7 +390,7 @@ dma_addr_t pci_map_single(struct pci_dev *pdev, void *ptr, size_t sz, int direct
base_paddr = __pa(oaddr & IO_PAGE_MASK);
ctx = 0;
if (iommu->iommu_ctxflush)
- ctx = iommu->iommu_cur_ctx++;
+ ctx = iommu_alloc_ctx(iommu);
if (strbuf->strbuf_enabled)
iopte_protection = IOPTE_STREAMING(ctx);
else
@@ -380,39 +410,53 @@ bad:
return PCI_DMA_ERROR_CODE;
}
-static void pci_strbuf_flush(struct pci_strbuf *strbuf, struct pci_iommu *iommu, u32 vaddr, unsigned long ctx, unsigned long npages)
+static void pci_strbuf_flush(struct pci_strbuf *strbuf, struct pci_iommu *iommu, u32 vaddr, unsigned long ctx, unsigned long npages, int direction)
{
int limit;
- PCI_STC_FLUSHFLAG_INIT(strbuf);
if (strbuf->strbuf_ctxflush &&
iommu->iommu_ctxflush) {
unsigned long matchreg, flushreg;
+ u64 val;
flushreg = strbuf->strbuf_ctxflush;
matchreg = PCI_STC_CTXMATCH_ADDR(strbuf, ctx);
- limit = 100000;
pci_iommu_write(flushreg, ctx);
- for(;;) {
- if (((long)pci_iommu_read(matchreg)) >= 0L)
- break;
- limit--;
- if (!limit)
- break;
- udelay(1);
+ val = pci_iommu_read(matchreg);
+ val &= 0xffff;
+ if (!val)
+ goto do_flush_sync;
+
+ while (val) {
+ if (val & 0x1)
+ pci_iommu_write(flushreg, ctx);
+ val >>= 1;
}
- if (!limit)
+ val = pci_iommu_read(matchreg);
+ if (unlikely(val)) {
printk(KERN_WARNING "pci_strbuf_flush: ctx flush "
- "timeout vaddr[%08x] ctx[%lx]\n",
- vaddr, ctx);
+ "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)
pci_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 == PCI_DMA_TODEVICE)
+ return;
+
+ PCI_STC_FLUSHFLAG_INIT(strbuf);
pci_iommu_write(strbuf->strbuf_fsync, strbuf->strbuf_flushflag_pa);
(void) pci_iommu_read(iommu->write_complete_reg);
@@ -466,7 +510,7 @@ void pci_unmap_single(struct pci_dev *pdev, dma_addr_t bus_addr, size_t sz, int
/* Step 1: Kick data out of streaming buffers if necessary. */
if (strbuf->strbuf_enabled)
- pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages);
+ pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
/* Step 2: Clear out first TSB entry. */
iopte_make_dummy(iommu, base);
@@ -474,6 +518,8 @@ void pci_unmap_single(struct pci_dev *pdev, dma_addr_t bus_addr, size_t sz, int
free_streaming_cluster(iommu, bus_addr - iommu->page_table_map_base,
npages, ctx);
+ iommu_free_ctx(iommu, ctx);
+
spin_unlock_irqrestore(&iommu->lock, flags);
}
@@ -613,7 +659,7 @@ int pci_map_sg(struct pci_dev *pdev, struct scatterlist *sglist, int nelems, int
/* Step 4: Choose a context if necessary. */
ctx = 0;
if (iommu->iommu_ctxflush)
- ctx = iommu->iommu_cur_ctx++;
+ ctx = iommu_alloc_ctx(iommu);
/* Step 5: Create the mappings. */
if (strbuf->strbuf_enabled)
@@ -678,7 +724,7 @@ void pci_unmap_sg(struct pci_dev *pdev, struct scatterlist *sglist, int nelems,
/* Step 1: Kick data out of streaming buffers if necessary. */
if (strbuf->strbuf_enabled)
- pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages);
+ pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
/* Step 2: Clear out first TSB entry. */
iopte_make_dummy(iommu, base);
@@ -686,6 +732,8 @@ void pci_unmap_sg(struct pci_dev *pdev, struct scatterlist *sglist, int nelems,
free_streaming_cluster(iommu, bus_addr - iommu->page_table_map_base,
npages, ctx);
+ iommu_free_ctx(iommu, ctx);
+
spin_unlock_irqrestore(&iommu->lock, flags);
}
@@ -724,7 +772,7 @@ void pci_dma_sync_single_for_cpu(struct pci_dev *pdev, dma_addr_t bus_addr, size
}
/* Step 2: Kick data out of streaming buffers. */
- pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages);
+ pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
spin_unlock_irqrestore(&iommu->lock, flags);
}
@@ -768,7 +816,7 @@ void pci_dma_sync_sg_for_cpu(struct pci_dev *pdev, struct scatterlist *sglist, i
i--;
npages = (IO_PAGE_ALIGN(sglist[i].dma_address + sglist[i].dma_length)
- bus_addr) >> IO_PAGE_SHIFT;
- pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages);
+ pci_strbuf_flush(strbuf, iommu, bus_addr, ctx, npages, direction);
spin_unlock_irqrestore(&iommu->lock, flags);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-25 20:21:30 +0000