[PATCH 08/26] MIPS: dma-default: Don't check hw_coherentio if device is non-coherent

From: Paul Burton
Date: Fri Aug 26 2016 - 11:40:15 EST


There are no cases where plat_device_is_coherent() will return zero
whilst hw_coherentio is non-zero, and acting any differently in such a
case doesn't make much sense - if a device is non-coherent with the CPU
caches then access to memory "coherent" with DMA must be uncached. Clean
up the nonsensical case.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---

arch/mips/mm/dma-default.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index a9c1e94..6540355 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -161,8 +161,7 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
*dma_handle = plat_map_dma_mem(dev, ret, size);
if (!plat_device_is_coherent(dev)) {
dma_cache_wback_inv((unsigned long) ret, size);
- if (!hw_coherentio)
- ret = UNCAC_ADDR(ret);
+ ret = UNCAC_ADDR(ret);
}

return ret;
@@ -190,7 +189,7 @@ static void mips_dma_free_coherent(struct device *dev, size_t size, void *vaddr,

plat_unmap_dma_mem(dev, dma_handle, size, DMA_BIDIRECTIONAL);

- if (!plat_device_is_coherent(dev) && !hw_coherentio)
+ if (!plat_device_is_coherent(dev))
addr = CAC_ADDR(addr);

page = virt_to_page((void *) addr);
@@ -210,7 +209,7 @@ static int mips_dma_mmap(struct device *dev, struct vm_area_struct *vma,
unsigned long pfn;
int ret = -ENXIO;

- if (!plat_device_is_coherent(dev) && !hw_coherentio)
+ if (!plat_device_is_coherent(dev))
addr = CAC_ADDR(addr);

pfn = page_to_pfn(virt_to_page((void *)addr));
--
2.9.3