parisc: Improve cache flushing for PCXL in arch_sync_dma_for_cpu()

[ Upstream commit 59fa12646d ]

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>
This commit is contained in:
Helge Deller 2023-05-17 15:52:30 +02:00 committed by Greg Kroah-Hartman
parent 0f32085e68
commit 6f50472d64

View file

@ -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();
}
}