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authorHelge Deller2023-05-17 15:52:30 +0200
committerGreg Kroah-Hartman2023-06-21 16:00:53 +0200
commite522a12e4892f99b4251dbdd9dcf37f8dc2cb90e (patch)
treed65942bb2b31c572c5e72a99246966fe5ae2f12d /arch
parent0b09b35cae865b383e206d2ab54ce4560859577c (diff)
parisc: Improve cache flushing for PCXL in arch_sync_dma_for_cpu()
[ Upstream commit 59fa12646d9f56c842b4d5b6418ed77af625c588 ] Add comment in arch_sync_dma_for_device() and handle the direction flag in arch_sync_dma_for_cpu(). When receiving data from the device (DMA_FROM_DEVICE) unconditionally purge the data cache in arch_sync_dma_for_cpu(). Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/parisc/kernel/pci-dma.c18
1 files changed, 17 insertions, 1 deletions
diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index ba87f791323b..71ed5391f29d 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -446,11 +446,27 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr,
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
+ /*
+ * fdc: The data cache line is written back to memory, if and only if
+ * it is dirty, and then invalidated from the data cache.
+ */
flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
}
void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
- flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
+ unsigned long addr = (unsigned long) phys_to_virt(paddr);
+
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ case DMA_BIDIRECTIONAL:
+ flush_kernel_dcache_range(addr, size);
+ return;
+ case DMA_FROM_DEVICE:
+ purge_kernel_dcache_range_asm(addr, addr + size);
+ return;
+ default:
+ BUG();
+ }
}