#define STRBUF_TAG_VALID 0x02UL
-static void sbus_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)
{
unsigned long n;
int limit;
- iommu->strbuf_flushflag = 0UL;
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);
if (!limit)
break;
udelay(1);
- membar("#LoadLoad");
+ rmb();
}
if (!limit)
printk(KERN_WARNING "sbus_strbuf_flush: flushflag timeout "
spin_lock_irqsave(&iommu->lock, flags);
free_streaming_cluster(iommu, dma_base, size >> IO_PAGE_SHIFT);
- sbus_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);
}
iommu = sdev->bus->iommu;
spin_lock_irqsave(&iommu->lock, flags);
free_streaming_cluster(iommu, dvma_base, size >> IO_PAGE_SHIFT);
- sbus_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);
}
size = (IO_PAGE_ALIGN(base + size) - (base & IO_PAGE_MASK));
spin_lock_irqsave(&iommu->lock, flags);
- sbus_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);
}
size = IO_PAGE_ALIGN(sg[i].dma_address + sg[i].dma_length) - base;
spin_lock_irqsave(&iommu->lock, flags);
- sbus_strbuf_flush(iommu, base, size >> IO_PAGE_SHIFT);
+ sbus_strbuf_flush(iommu, base, size >> IO_PAGE_SHIFT, direction);
spin_unlock_irqrestore(&iommu->lock, flags);
}