diff options
| author |   Jani Nikula <jani.nikula@intel.com> | 2021-09-09 15:51:53 +0300 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2021-09-20 18:43:58 +0300 |
| commit | 054ce0bce22eeb714c6cc3808869a326d0611792 (patch) | |
| tree | 224c4f21356124136845749e608c12d520fb4d85 /drivers/gpu/drm | |
| parent | drm/i915/display/adlp: Add new PSR2 workarounds (diff) | |
| download | linux-dev-054ce0bce22eeb714c6cc3808869a326d0611792.tar.xz linux-dev-054ce0bce22eeb714c6cc3808869a326d0611792.zip | |
drm/dp: add DP 2.0 UHBR link rate and bw code conversions
The bw code equals link_rate / 0.27 Gbps only for 8b/10b link
rates. Handle DP 2.0 UHBR rates as special cases, though this is not
pretty.
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/cab4edda8834d6b4db610fabb5e1f1f18ae33c2c.1631191763.git.jani.nikula@intel.com
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 6d0f2c447f3b..9b2a2961fca8 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -207,15 +207,33 @@ EXPORT_SYMBOL(drm_dp_lttpr_link_train_channel_eq_delay); u8 drm_dp_link_rate_to_bw_code(int link_rate) { - /* Spec says link_bw = link_rate / 0.27Gbps */ - return link_rate / 27000; + switch (link_rate) { + case 1000000: + return DP_LINK_BW_10; + case 1350000: + return DP_LINK_BW_13_5; + case 2000000: + return DP_LINK_BW_20; + default: + /* Spec says link_bw = link_rate / 0.27Gbps */ + return link_rate / 27000; + } } EXPORT_SYMBOL(drm_dp_link_rate_to_bw_code); int drm_dp_bw_code_to_link_rate(u8 link_bw) { - /* Spec says link_rate = link_bw * 0.27Gbps */ - return link_bw * 27000; + switch (link_bw) { + case DP_LINK_BW_10: + return 1000000; + case DP_LINK_BW_13_5: + return 1350000; + case DP_LINK_BW_20: + return 2000000; + default: + /* Spec says link_rate = link_bw * 0.27Gbps */ + return link_bw * 27000; + } } EXPORT_SYMBOL(drm_dp_bw_code_to_link_rate); |