On Mon, Feb 01, 2021 at 11:02:28PM +0800, Lee Shawn C wrote:
> According to Bspec #20124, max link rate table for DP was updated
> at BDB version 230. Max link rate can support upto UHBR.
> 
> After migrate to BDB v230, the definition for LBR, HBR2 and HBR3
> were changed. For backward compatibility. If BDB version was
> from 216 to 229. Driver have to follow original rule to configure
> DP max link rate value from VBT.
> 
> Cc: Ville Syrjala <[email protected]>
> Cc: Imre Deak <[email protected]>
> Cc: Jani Nikula <[email protected]>
> Cc: Cooper Chiou <[email protected]>
> Cc: William Tseng <[email protected]>
> Signed-off-by: Lee Shawn C <[email protected]>
> ---
>  drivers/gpu/drm/i915/display/intel_bios.c     | 24 ++++++++++++++++++-
>  drivers/gpu/drm/i915/display/intel_vbt_defs.h | 14 +++++++----
>  2 files changed, 32 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c 
> b/drivers/gpu/drm/i915/display/intel_bios.c
> index 04337ac6f8c4..be1f732e6550 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -1876,7 +1876,15 @@ static void parse_ddi_port(struct drm_i915_private 
> *dev_priv,
>       /* DP max link rate for CNL+ */
>       if (bdb_version >= 216) {
>               switch (child->dp_max_link_rate) {
> -             default:
> +             case VBT_DP_MAX_LINK_RATE_UHBR20:
> +                     info->dp_max_link_rate = 2000000;
> +                     break;
> +             case VBT_DP_MAX_LINK_RATE_UHBR13P5:
> +                     info->dp_max_link_rate = 1350000;
> +                     break;
> +             case VBT_DP_MAX_LINK_RATE_UHBR10:
> +                     info->dp_max_link_rate = 1000000;
> +                     break;
>               case VBT_DP_MAX_LINK_RATE_HBR3:
>                       info->dp_max_link_rate = 810000;
>                       break;
> @@ -1889,7 +1897,21 @@ static void parse_ddi_port(struct drm_i915_private 
> *dev_priv,
>               case VBT_DP_MAX_LINK_RATE_LBR:
>                       info->dp_max_link_rate = 162000;
>                       break;
> +             case VBT_DP_MAX_LINK_RATE_DEFAULT:
> +             default:
> +                     info->dp_max_link_rate = 0;
> +                     break;
> +             }
> +
> +             if (bdb_version < 230) {
> +                     if (child->dp_max_link_rate == 
> VBT_DP_MAX_LINK_RATE_DEFAULT)
> +                             info->dp_max_link_rate = 810000;
> +                     else if (child->dp_max_link_rate == 
> VBT_DP_MAX_LINK_RATE_LBR)
> +                             info->dp_max_link_rate = 540000;
> +                     else if (child->dp_max_link_rate == 
> VBT_DP_MAX_LINK_RATE_HBR2)
> +                             info->dp_max_link_rate = 162000;
>               }

I would split this into two separate functions, one does the new
mapping, the other the old mapping. 

> +
>               drm_dbg_kms(&dev_priv->drm,
>                           "VBT DP max link rate for port %c: %d\n",
>                           port_name(port), info->dp_max_link_rate);
> diff --git a/drivers/gpu/drm/i915/display/intel_vbt_defs.h 
> b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> index 6d10fa037751..578a54b33f32 100644
> --- a/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> +++ b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> @@ -343,10 +343,14 @@ enum vbt_gmbus_ddi {
>  #define DP_AUX_H 0x80
>  #define DP_AUX_I 0x90
>  
> -#define VBT_DP_MAX_LINK_RATE_HBR3    0
> -#define VBT_DP_MAX_LINK_RATE_HBR2    1
> +#define VBT_DP_MAX_LINK_RATE_DEFAULT 0
> +#define VBT_DP_MAX_LINK_RATE_LBR     1
>  #define VBT_DP_MAX_LINK_RATE_HBR     2
> -#define VBT_DP_MAX_LINK_RATE_LBR     3
> +#define VBT_DP_MAX_LINK_RATE_HBR2    3
> +#define VBT_DP_MAX_LINK_RATE_HBR3    4
> +#define VBT_DP_MAX_LINK_RATE_UHBR10  5
> +#define VBT_DP_MAX_LINK_RATE_UHBR13P5        6
> +#define VBT_DP_MAX_LINK_RATE_UHBR20  7

And we should keep both old and new names for these.

Sadly I can't right now check the spec since it no longer has the
old stuff apparently, and the VBT section got moved around so the
history no longer shows anything either :( I'll have to pull the whole
thing down I guess so I can double check against the old version.

>  
>  /*
>   * The child device config, aka the display device data structure, provides a
> @@ -445,8 +449,8 @@ struct child_device_config {
>       u16 dp_gpio_pin_num;                                    /* 195 */
>       u8 dp_iboost_level:4;                                   /* 196 */
>       u8 hdmi_iboost_level:4;                                 /* 196 */
> -     u8 dp_max_link_rate:2;                                  /* 216 CNL+ */
> -     u8 dp_max_link_rate_reserved:6;                         /* 216 */
> +     u8 dp_max_link_rate:3;                                  /* 230 */
> +     u8 dp_max_link_rate_reserved:5;                         /* 230 */
>  } __packed;
>  
>  struct bdb_general_definitions {
> -- 
> 2.17.1

-- 
Ville Syrjälä
Intel
_______________________________________________
Intel-gfx mailing list
[email protected]
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to