Re: [Patch v5 5/8] firmware: qcom: scm: Convert to streaming DMA APIS

From: Bjorn Andersson
Date: Fri May 13 2016 - 19:49:01 EST


On Thu 12 May 20:46 PDT 2016, Andy Gross wrote:

> This patch converts the Qualcomm SCM driver to use the streaming DMA APIs
> for communication buffers.
>
> Signed-off-by: Andy Gross <andy.gross@xxxxxxxxxx>
> ---
> drivers/firmware/qcom_scm-32.c | 189 +++++++++++------------------------------
> drivers/firmware/qcom_scm.c | 6 +-
> drivers/firmware/qcom_scm.h | 10 ++-
> 3 files changed, 59 insertions(+), 146 deletions(-)
>
> diff --git a/drivers/firmware/qcom_scm-32.c b/drivers/firmware/qcom_scm-32.c
[..]
> +static int qcom_scm_call(struct device *dev, u32 svc_id, u32 cmd_id,
> + const void *cmd_buf, size_t cmd_len, void *resp_buf,
> + size_t resp_len)
> {
> int ret;
> struct qcom_scm_command *cmd;
> struct qcom_scm_response *rsp;
> - unsigned long start, end;
> + size_t alloc_len = sizeof(*cmd) + cmd_len + sizeof(*rsp) + resp_len;
> + dma_addr_t cmd_phys;
>
> - cmd = alloc_qcom_scm_command(cmd_len, resp_len);
> + cmd = kzalloc(PAGE_ALIGN(alloc_len), GFP_KERNEL);
> if (!cmd)
> return -ENOMEM;
>
> + cmd->len = cpu_to_le32(alloc_len);
> + cmd->buf_offset = cpu_to_le32(sizeof(*cmd));
> + cmd->resp_hdr_offset = cpu_to_le32(sizeof(*cmd) + cmd_len);
> +
> cmd->id = cpu_to_le32((svc_id << 10) | cmd_id);
> if (cmd_buf)
> - memcpy(qcom_scm_get_command_buffer(cmd), cmd_buf, cmd_len);
> + memcpy(cmd->buf, cmd_buf, cmd_len);
> +
> + rsp = (void *)cmd->buf + le32_to_cpu(cmd->resp_hdr_offset);

I believe resp_hdr_offset counts from the beginning of the buffer and
that this therefor is supposed to be:

rsp = (void *)cmd + le32_to_cpu(cmd->resp_hdr_offset);

With that corrected, feel free to add:

Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Regards,
Bjorn