sysmo-bts
/
barebox
9
0
Fork 0
Code Releases Activity

implement dma_alloc_writecombine 

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Sascha Hauer 2015-08-07 11:51:29 +02:00
parent 77ac6b4786
commit 3c76d02aeb
2 changed files with 21 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/arm/cpu/mmu.c
View File

@ -66,6 +66,7 @@ static inline void tlb_invalidate(void)
}
#define PTE_FLAGS_CACHED_V7 (PTE_EXT_TEX(1) | PTE_BUFFERABLE | PTE_CACHEABLE)
#define PTE_FLAGS_WC_V7 PTE_EXT_TEX(1)
#define PTE_FLAGS_UNCACHED_V7 (0)
#define PTE_FLAGS_CACHED_V4 (PTE_SMALL_AP_UNO_SRW | PTE_BUFFERABLE | PTE_CACHEABLE)
#define PTE_FLAGS_UNCACHED_V4 PTE_SMALL_AP_UNO_SRW
@ -75,6 +76,7 @@ static inline void tlb_invalidate(void)
* This will be determined at runtime.
*/
static uint32_t pte_flags_cached;
static uint32_t pte_flags_wc;
static uint32_t pte_flags_uncached;
#define PTE_MASK ((1 << 12) - 1)
@ -325,9 +327,11 @@ static int mmu_init(void)
if (cpu_architecture() >= CPU_ARCH_ARMv7) {
pte_flags_cached = PTE_FLAGS_CACHED_V7;
pte_flags_wc = PTE_FLAGS_WC_V7;
pte_flags_uncached = PTE_FLAGS_UNCACHED_V7;
} else {
pte_flags_cached = PTE_FLAGS_CACHED_V4;
pte_flags_wc = PTE_FLAGS_UNCACHED_V4;
pte_flags_uncached = PTE_FLAGS_UNCACHED_V4;
}
@ -408,6 +412,22 @@ void *dma_alloc_coherent(size_t size, dma_addr_t *dma_handle)
return ret;
}
void *dma_alloc_writecombine(size_t size, dma_addr_t *dma_handle)
{
void *ret;
size = PAGE_ALIGN(size);
ret = xmemalign(PAGE_SIZE, size);
if (dma_handle)
*dma_handle = (dma_addr_t)ret;
dma_inv_range((unsigned long)ret, (unsigned long)ret + size);
remap_range(ret, size, pte_flags_wc);
return ret;
}
unsigned long virt_to_phys(volatile void *virt)
{
return (unsigned long)virt;

1
include/dma.h
View File

@ -39,5 +39,6 @@ void dma_sync_single_for_device(unsigned long address, size_t size,
void *dma_alloc_coherent(size_t size, dma_addr_t *dma_handle);
void dma_free_coherent(void *mem, dma_addr_t dma_handle, size_t size);
void *dma_alloc_writecombine(size_t size, dma_addr_t *dma_handle);
#endif /* __DMA_H */