Re: [PATCH v6 2/5] drm: add constant N value in helper file

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 08 Jun 2020, Tanmay Shah <tanmay@codeaurora.org> wrote:
> From: Chandan Uddaraju <chandanu@codeaurora.org>
>
> The constant N value (0x8000) is used by i915 DP
> driver. Define this value in dp helper header file
> to use in multiple Display Port drivers. Change
> i915 driver accordingly.
>
> Change in v6: Change commit message
>
> Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>
> Signed-off-by: Vara Reddy <varar@codeaurora.org>
> Signed-off-by: Tanmay Shah <tanmay@codeaurora.org>

Acked-by: Jani Nikula <jani.nikula@intel.com>

for merging via drm-misc if that helps you.


> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 2 +-
>  include/drm/drm_dp_helper.h                  | 1 +
>  2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 9ea1a39..4b2cfff 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -8085,7 +8085,7 @@ static void compute_m_n(unsigned int m, unsigned int n,
>  	 * which the devices expect also in synchronous clock mode.
>  	 */
>  	if (constant_n)
> -		*ret_n = 0x8000;
> +		*ret_n = DP_LINK_CONSTANT_N_VALUE;
>  	else
>  		*ret_n = min_t(unsigned int, roundup_pow_of_two(n), DATA_LINK_N_MAX);
>  
> diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
> index 2035ac4..589132a 100644
> --- a/include/drm/drm_dp_helper.h
> +++ b/include/drm/drm_dp_helper.h
> @@ -1134,6 +1134,7 @@
>  #define DP_MST_PHYSICAL_PORT_0 0
>  #define DP_MST_LOGICAL_PORT_0 8
>  
> +#define DP_LINK_CONSTANT_N_VALUE 0x8000
>  #define DP_LINK_STATUS_SIZE	   6
>  bool drm_dp_channel_eq_ok(const u8 link_status[DP_LINK_STATUS_SIZE],
>  			  int lane_count);

-- 
Jani Nikula, Intel Open Source Graphics Center