[PATCH 12/21] mips: dma-mapping: split out cache operation logic

Arnd Bergmann
2023-03-27T12:16:34Z

From: Arnd Bergmann <arnd@arndb.de>

The mips arch_sync_dma_for_device()/arch_sync_dma_for_cpu() functions
behave the same way as on other architectures, but in order to unify
the implementations, the code needs to be rearranged to pick the type
of cache operation in the outermost function.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
arch/mips/mm/dma-noncoherent.c | 75 ++++++++++++++--------------------
1 file changed, 30 insertions(+), 45 deletions(-)

diff --git a/arch/mips/mm/dma-noncoherent.c b/arch/mips/mm/dma-noncoherent.c
index b4350faf4f1e..b9d68bcc5d53 100644
--- a/arch/mips/mm/dma-noncoherent.c
+++ b/arch/mips/mm/dma-noncoherent.c
@@ -54,50 +54,13 @@ void *arch_dma_set_uncached(void *addr, size_t size)
return (void *)(__pa(addr) + UNCAC_BASE);
}

-static inline void dma_sync_virt_for_device(void *addr, size_t size,
- enum dma_data_direction dir)
-{
- switch (dir) {
- case DMA_TO_DEVICE:
- dma_cache_wback((unsigned long)addr, size);
- break;
- case DMA_FROM_DEVICE:
- dma_cache_inv((unsigned long)addr, size);
- break;
- case DMA_BIDIRECTIONAL:
- if (IS_ENABLED(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) &&
- cpu_needs_post_dma_flush())
- dma_cache_wback((unsigned long)addr, size);
- else
- dma_cache_wback_inv((unsigned long)addr, size);
- break;
- default:
- BUG();
- }
-}
-
-static inline void dma_sync_virt_for_cpu(void *addr, size_t size,
- enum dma_data_direction dir)
-{
- switch (dir) {
- case DMA_TO_DEVICE:
- break;
- case DMA_FROM_DEVICE:
- case DMA_BIDIRECTIONAL:
- dma_cache_inv((unsigned long)addr, size);
- break;
- default:
- BUG();
- }
-}
-
/*
* A single sg entry may refer to multiple physically contiguous pages. But
* we still need to process highmem pages individually. If highmem is not
* configured then the bulk of this loop gets optimized out.
*/
static inline void dma_sync_phys(phys_addr_t paddr, size_t size,
- enum dma_data_direction dir, bool for_device)
+ void(*cache_op)(unsigned long start, unsigned long size))
{
struct page *page = pfn_to_page(paddr >> PAGE_SHIFT);
unsigned long offset = paddr & ~PAGE_MASK;
@@ -113,10 +76,7 @@ static inline void dma_sync_phys(phys_addr_t paddr, size_t size,
}

addr = kmap_atomic(page);
- if (for_device)
- dma_sync_virt_for_device(addr + offset, len, dir);
- else
- dma_sync_virt_for_cpu(addr + offset, len, dir);
+ cache_op((unsigned long)addr + offset, len);
kunmap_atomic(addr);

offset = 0;
@@ -128,15 +88,40 @@ static inline void dma_sync_phys(phys_addr_t paddr, size_t size,
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
- dma_sync_phys(paddr, size, dir, true);
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ dma_sync_phys(paddr, size, _dma_cache_wback);
+ break;
+ case DMA_FROM_DEVICE:
+ dma_sync_phys(paddr, size, _dma_cache_inv);
+ break;
+ case DMA_BIDIRECTIONAL:
+ if (IS_ENABLED(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) &&
+ cpu_needs_post_dma_flush())
+ dma_sync_phys(paddr, size, _dma_cache_wback);
+ else
+ dma_sync_phys(paddr, size, _dma_cache_wback_inv);
+ break;
+ default:
+ break;
+ }
}

#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
- if (cpu_needs_post_dma_flush())
- dma_sync_phys(paddr, size, dir, false);
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ break;
+ case DMA_FROM_DEVICE:
+ case DMA_BIDIRECTIONAL:
+ if (cpu_needs_post_dma_flush())
+ dma_sync_phys(paddr, size, _dma_cache_inv);
+ break;
+ default:
+ break;
+ }
}
#endif

--
2.39.2