[PATCH] rmem: support for dma_addr different from phys_addr

From: Vladimir Kondratiev
Date: Tue Jul 04 2017 - 08:54:25 EST


On some systems, dma address differs from physical one due to
various reasons.

dma_init_coherent_memory is aware of it, it takes both
phys_addr_t and dma_addt_t arguments for memory block.
However, rmem_dma_device_init passes physical address for DMA one.

Fix this, using phys_to_dma(). This assumes the whole buffer has
same offset between physical and dma addresses.

Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@xxxxxxxxx>
---
drivers/base/dma-coherent.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index 640a7e63c453..5371cb19c918 100644
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c
@@ -292,7 +292,8 @@ static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
struct dma_coherent_mem *mem = rmem->priv;

if (!mem &&
- !dma_init_coherent_memory(rmem->base, rmem->base, rmem->size,
+ !dma_init_coherent_memory(rmem->base, phys_to_dma(dev, rmem->base),
+ rmem->size,
DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE,
&mem)) {
pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n",
--
2.11.0