Re: [PATCH 1/3] crypto: marvell/cesa - replace dma_to_phys with dma_map_single

From: okaya
Date: Thu Mar 17 2016 - 19:17:30 EST

On 2016-03-17 18:54, Russell King - ARM Linux wrote:
On Thu, Mar 17, 2016 at 06:02:15PM -0400, Sinan Kaya wrote:
Getting ready to remove dma_to_phys API. Drivers should not be
using this API for DMA operations. Instead, they should go
through the dma_map or dma_alloc APIs.

Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
drivers/crypto/marvell/cesa.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/marvell/cesa.c b/drivers/crypto/marvell/cesa.c
index c0656e7..52ddfa4 100644
--- a/drivers/crypto/marvell/cesa.c
+++ b/drivers/crypto/marvell/cesa.c
@@ -350,8 +350,8 @@ static int mv_cesa_get_sram(struct platform_device *pdev, int idx)
if (IS_ERR(engine->sram))
return PTR_ERR(engine->sram);

- engine->sram_dma = phys_to_dma(cesa->dev,
- (phys_addr_t)res->start);
+ engine->sram_dma = dma_map_single(cesa->dev, engine->sram,


dma_map_single(struct device *dev, void *cpu_addr, size_t size,
enum dma_data_direction direction)

Notes: Not all memory regions in a machine can be mapped by this API.
Further, contiguous kernel virtual space may not be contiguous as
physical memory. Since this API does not provide any scatter/gather
capability, it will fail if the user tries to map a non-physically
contiguous piece of memory. For this reason, memory to be mapped by
this API should be obtained from sources which guarantee it to be
physically contiguous (like kmalloc).

Specifically, ioremapped memory will *not* work as you expect with

What is the correct way? I don't want to write engine->sram_dma = sram