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Diffstat (limited to 'arch/sparc64/kernel/sbus.c')
-rw-r--r--arch/sparc64/kernel/sbus.c41
1 files changed, 32 insertions, 9 deletions
diff --git a/arch/sparc64/kernel/sbus.c b/arch/sparc64/kernel/sbus.c
index 14d9c3a21b9..89f5e019f24 100644
--- a/arch/sparc64/kernel/sbus.c
+++ b/arch/sparc64/kernel/sbus.c
@@ -117,19 +117,42 @@ static void iommu_flush(struct sbus_iommu *iommu, u32 base, unsigned long npages
#define STRBUF_TAG_VALID 0x02UL
-static void strbuf_flush(struct sbus_iommu *iommu, u32 base, unsigned long npages)
+static void sbus_strbuf_flush(struct sbus_iommu *iommu, u32 base, unsigned long npages, int direction)
{
- iommu->strbuf_flushflag = 0UL;
- while (npages--)
- upa_writeq(base + (npages << IO_PAGE_SHIFT),
+ unsigned long n;
+ int limit;
+
+ n = npages;
+ while (n--)
+ upa_writeq(base + (n << IO_PAGE_SHIFT),
iommu->strbuf_regs + STRBUF_PFLUSH);
+ /* If the device could not have possibly put dirty data into
+ * the streaming cache, no flush-flag synchronization needs
+ * to be performed.
+ */
+ if (direction == SBUS_DMA_TODEVICE)
+ return;
+
+ iommu->strbuf_flushflag = 0UL;
+
/* Whoopee cushion! */
upa_writeq(__pa(&iommu->strbuf_flushflag),
iommu->strbuf_regs + STRBUF_FSYNC);
upa_readq(iommu->sbus_control_reg);
- while (iommu->strbuf_flushflag == 0UL)
+
+ limit = 100000;
+ while (iommu->strbuf_flushflag == 0UL) {
+ limit--;
+ if (!limit)
+ break;
+ udelay(1);
membar("#LoadLoad");
+ }
+ if (!limit)
+ printk(KERN_WARNING "sbus_strbuf_flush: flushflag timeout "
+ "vaddr[%08x] npages[%ld]\n",
+ base, npages);
}
static iopte_t *alloc_streaming_cluster(struct sbus_iommu *iommu, unsigned long npages)
@@ -406,7 +429,7 @@ void sbus_unmap_single(struct sbus_dev *sdev, dma_addr_t dma_addr, size_t size,
spin_lock_irqsave(&iommu->lock, flags);
free_streaming_cluster(iommu, dma_base, size >> IO_PAGE_SHIFT);
- strbuf_flush(iommu, dma_base, size >> IO_PAGE_SHIFT);
+ sbus_strbuf_flush(iommu, dma_base, size >> IO_PAGE_SHIFT, direction);
spin_unlock_irqrestore(&iommu->lock, flags);
}
@@ -569,7 +592,7 @@ void sbus_unmap_sg(struct sbus_dev *sdev, struct scatterlist *sg, int nents, int
iommu = sdev->bus->iommu;
spin_lock_irqsave(&iommu->lock, flags);
free_streaming_cluster(iommu, dvma_base, size >> IO_PAGE_SHIFT);
- strbuf_flush(iommu, dvma_base, size >> IO_PAGE_SHIFT);
+ sbus_strbuf_flush(iommu, dvma_base, size >> IO_PAGE_SHIFT, direction);
spin_unlock_irqrestore(&iommu->lock, flags);
}
@@ -581,7 +604,7 @@ void sbus_dma_sync_single_for_cpu(struct sbus_dev *sdev, dma_addr_t base, size_t
size = (IO_PAGE_ALIGN(base + size) - (base & IO_PAGE_MASK));
spin_lock_irqsave(&iommu->lock, flags);
- strbuf_flush(iommu, base & IO_PAGE_MASK, size >> IO_PAGE_SHIFT);
+ sbus_strbuf_flush(iommu, base & IO_PAGE_MASK, size >> IO_PAGE_SHIFT, direction);
spin_unlock_irqrestore(&iommu->lock, flags);
}
@@ -605,7 +628,7 @@ void sbus_dma_sync_sg_for_cpu(struct sbus_dev *sdev, struct scatterlist *sg, int
size = IO_PAGE_ALIGN(sg[i].dma_address + sg[i].dma_length) - base;
spin_lock_irqsave(&iommu->lock, flags);
- strbuf_flush(iommu, base, size >> IO_PAGE_SHIFT);
+ sbus_strbuf_flush(iommu, base, size >> IO_PAGE_SHIFT, direction);
spin_unlock_irqrestore(&iommu->lock, flags);
}