Re: [PATCH v2 12/16] drm/msm/dsi: Add support for SM8750

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 17/02/2025 20:05, Dmitry Baryshkov wrote:
> On Mon, Feb 17, 2025 at 05:41:33PM +0100, Krzysztof Kozlowski wrote:
>> Add support for DSI on Qualcomm SM8750 SoC with notable difference:
>>
>> DSI PHY PLLs, the parents of pixel and byte clocks, cannot be used as
>> parents before DSI PHY is configured and the PLLs are prepared with
>> initial rate is set.  Therefore assigned-clock-parents are not working
>> here and driver is responsible for reparenting clocks with proper
>> procedure: see dsi_clk_init_6g_v2_9().
>>
>> Part of the change is exactly the same as CLK_OPS_PARENT_ENABLE, however
>> CLK_OPS_PARENT_ENABLE won't work here because assigned-clock-parents are
>> executed way too early - before DSI PHY is configured.
>>
>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>
>> ---
>>
>> SM8750 DSI PHY also needs Dmitry's patch:
>> https://patchwork.freedesktop.org/patch/542000/?series=119177&rev=1
>> (or some other way of correct early setting of the DSI PHY PLL rate)
>> ---
>>  drivers/gpu/drm/msm/dsi/dsi.h      |  2 +
>>  drivers/gpu/drm/msm/dsi/dsi_cfg.c  | 25 ++++++++++++
>>  drivers/gpu/drm/msm/dsi/dsi_cfg.h  |  1 +
>>  drivers/gpu/drm/msm/dsi/dsi_host.c | 80 ++++++++++++++++++++++++++++++++++++++
>>  4 files changed, 108 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
>> index 87496db203d6c7582eadcb74e94eb56a219df292..93c028a122f3a59b1632da76472e0a3e781c6ae8 100644
>> --- a/drivers/gpu/drm/msm/dsi/dsi.h
>> +++ b/drivers/gpu/drm/msm/dsi/dsi.h
>> @@ -98,6 +98,7 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi);
>>  int msm_dsi_runtime_suspend(struct device *dev);
>>  int msm_dsi_runtime_resume(struct device *dev);
>>  int dsi_link_clk_set_rate_6g(struct msm_dsi_host *msm_host);
>> +int dsi_link_clk_set_rate_6g_v2_9(struct msm_dsi_host *msm_host);
>>  int dsi_link_clk_set_rate_v2(struct msm_dsi_host *msm_host);
>>  int dsi_link_clk_enable_6g(struct msm_dsi_host *msm_host);
>>  int dsi_link_clk_enable_v2(struct msm_dsi_host *msm_host);
>> @@ -115,6 +116,7 @@ int dsi_dma_base_get_6g(struct msm_dsi_host *msm_host, uint64_t *iova);
>>  int dsi_dma_base_get_v2(struct msm_dsi_host *msm_host, uint64_t *iova);
>>  int dsi_clk_init_v2(struct msm_dsi_host *msm_host);
>>  int dsi_clk_init_6g_v2(struct msm_dsi_host *msm_host);
>> +int dsi_clk_init_6g_v2_9(struct msm_dsi_host *msm_host);
>>  int dsi_calc_clk_rate_v2(struct msm_dsi_host *msm_host, bool is_bonded_dsi);
>>  int dsi_calc_clk_rate_6g(struct msm_dsi_host *msm_host, bool is_bonded_dsi);
>>  void msm_dsi_host_snapshot(struct msm_disp_state *disp_state, struct mipi_dsi_host *host);
>> diff --git a/drivers/gpu/drm/msm/dsi/dsi_cfg.c b/drivers/gpu/drm/msm/dsi/dsi_cfg.c
>> index 7754dcec33d06e3d6eb8a9d55e53f24af073adb9..e2a8d6fcc45b6c207a3018ea7c8744fcf34dabd2 100644
>> --- a/drivers/gpu/drm/msm/dsi/dsi_cfg.c
>> +++ b/drivers/gpu/drm/msm/dsi/dsi_cfg.c
>> @@ -205,6 +205,17 @@ static const struct msm_dsi_config sm8650_dsi_cfg = {
>>  	},
>>  };
>>  
>> +static const struct msm_dsi_config sm8750_dsi_cfg = {
> 
> Can we use sm8650_dsi_cfg instead? What is the difference?

Yeah, I'll changeit. I think I was looking at this even and could not
find differences.



Best regards,
Krzysztof