Re: [PATCH] Platform: goldfish: goldfish_pipe.c: Add DMA support using managed version
On Fri, 2016-02-12 at 12:53 +0530, Shraddha Barke wrote:
> setup_access_params_addr has 2 goals-
>
> -Initialize the access_params field so that it can be used to send and read
> commands from the device in access_with_param
> -Get a bus address for the allocated memory to transfer to the device.
>
> Replace the combination of devm_kzalloc and _pa() with dmam_alloc_coherent.
trivia:
> diff --git a/drivers/platform/goldfish/goldfish_pipe.c
> b/drivers/platform/goldfish/goldfish_pipe.c
[]
> @@ -217,17 +218,18 @@ static int valid_batchbuffer_addr(struct
> goldfish_pipe_dev *dev,
> static int setup_access_params_addr(struct platform_device *pdev,
> struct goldfish_pipe_dev *dev)
> {
> - u64 paddr;
> + dma_addr_t dma_handle;
> struct access_params *aps;
>
> - aps = devm_kzalloc(&pdev->dev, sizeof(struct access_params),
> GFP_KERNEL);
> - if (!aps)
> - return -1;
> + aps = dmam_alloc_coherent(&pdev->dev, sizeof(struct access_params),
> + &dma_handle, GFP_KERNEL);
> + if (!aps) {
> + dev_err(&pdev->dev, "allocate buffer failed\n");
This is still an unnecessary allocation failure message.
There's already a generic OOM message and stack dump emitted.
Re: [PATCH] Platform: goldfish: goldfish_pipe.c: Add DMA support using managed version
On Sat, Feb 06, 2016 at 10:36:20AM +0530, Shraddha Barke wrote: > setup_access_params_addr has 2 goals- > > -Initialize the access_params field so that it can be used to send and read > commands from the device in access_with_param > -Get a bus address for the allocated memory to transfer to the device. > > Replace the combination of devm_kzalloc and _pa() with dmam_alloc_coherent. > Coherent mapping guarantees that the device and CPU are in sync. > > Signed-off-by: Shraddha Barke > --- > drivers/platform/goldfish/goldfish_pipe.c | 14 +++--- > 1 file changed, 7 insertions(+), 7 deletions(-) Doesn't apply to my char-misc tree anymore due to other changes in the driver, can you rebase and resend? thanks, greg k-h
Re: [PATCH] Platform: goldfish: goldfish_pipe.c: Add DMA support using managed version
On Sat, 2016-01-23 at 01:21 +0530, Shraddha Barke wrote:
> Function setup_access_params_addr is called only from probe function, hence
> managed version dmam_alloc_coherent is used.
trivia:
> diff --git a/drivers/platform/goldfish/goldfish_pipe.c
> b/drivers/platform/goldfish/goldfish_pipe.c
[]
> @@ -217,17 +218,19 @@ static int valid_batchbuffer_addr(struct
> goldfish_pipe_dev *dev,
> static int setup_access_params_addr(struct platform_device *pdev,
> struct goldfish_pipe_dev *dev)
> {
> - u64 paddr;
> + dma_addr_t dma_handle;
> struct access_params *aps;
>
> - aps = devm_kzalloc(&pdev->dev, sizeof(struct access_params),
> GFP_KERNEL);
> - if (!aps)
> - return -1;
> + aps = dmam_alloc_coherent(&pdev->dev, sizeof(struct access_params),
> + &dma_handle, GFP_KERNEL);
> + if (!aps) {
> + dev_err(&pdev->dev, "allocate buffer failed\n");
Unnecessary error message
> + return -ENOMEM;
> + }
>
> - /* FIXME */
> - paddr = __pa(aps);
> - writel((u32)(paddr >> 32), dev->base + PIPE_REG_PARAMS_ADDR_HIGH);
> - writel((u32)paddr, dev->base + PIPE_REG_PARAMS_ADDR_LOW);
> + writel((u32)((u64)dma_handle >> 32), dev->base +
> + PIPE_REG_PARAMS_ADDR_HIGH);
> + writel((u32)dma_handle, dev->base + PIPE_REG_PARAMS_ADDR_LOW);
Probably better to use upper_32_bits and lower_32_bits
