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 Signed-off-by: Jani Nikula jani.nikula@intel.com --- drivers/gpu/drm/drm_dp_helper.c | 26 ++++++++++++++++++++++---- 1 file 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);