Commit 3c5a62b5 authored by Yuanhan Liu's avatar Yuanhan Liu Committed by Chris Wilson

drm/i915: fix calculation of eDP signal levels on Sandybridge

Some voltage swing/pre-emphasis level use the same value on eDP
Sandybridge, like 400mv_0db and 600mv_0db are with the same value
of (0x0 << 22). So, fix them, and point out the value if it isn't
a supported voltage swing/pre-emphasis level.
Signed-off-by: default avatarYuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
parent f5afcd3d
......@@ -3174,10 +3174,11 @@
#define EDP_LINK_TRAIN_600MV_3_5DB_SNB_A (0x01<<22)
#define EDP_LINK_TRAIN_800MV_0DB_SNB_A (0x0<<22)
/* SNB B-stepping */
#define EDP_LINK_TRAIN_400MV_0DB_SNB_B (0x0<<22)
#define EDP_LINK_TRAIN_400MV_6DB_SNB_B (0x3a<<22)
#define EDP_LINK_TRAIN_600MV_3_5DB_SNB_B (0x39<<22)
#define EDP_LINK_TRAIN_800MV_0DB_SNB_B (0x38<<22)
#define EDP_LINK_TRAIN_400_600MV_0DB_SNB_B (0x0<<22)
#define EDP_LINK_TRAIN_400MV_3_5DB_SNB_B (0x1<<22)
#define EDP_LINK_TRAIN_400_600MV_6DB_SNB_B (0x3a<<22)
#define EDP_LINK_TRAIN_600_800MV_3_5DB_SNB_B (0x39<<22)
#define EDP_LINK_TRAIN_800_1200MV_0DB_SNB_B (0x38<<22)
#define EDP_LINK_TRAIN_VOL_EMP_MASK_SNB (0x3f<<22)
#define FORCEWAKE 0xA18C
......
......@@ -1153,18 +1153,27 @@ intel_dp_signal_levels(uint8_t train_set, int lane_count)
static uint32_t
intel_gen6_edp_signal_levels(uint8_t train_set)
{
switch (train_set & (DP_TRAIN_VOLTAGE_SWING_MASK|DP_TRAIN_PRE_EMPHASIS_MASK)) {
int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
DP_TRAIN_PRE_EMPHASIS_MASK);
switch (signal_levels) {
case DP_TRAIN_VOLTAGE_SWING_400 | DP_TRAIN_PRE_EMPHASIS_0:
return EDP_LINK_TRAIN_400MV_0DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_600 | DP_TRAIN_PRE_EMPHASIS_0:
return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_400 | DP_TRAIN_PRE_EMPHASIS_3_5:
return EDP_LINK_TRAIN_400MV_3_5DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_400 | DP_TRAIN_PRE_EMPHASIS_6:
return EDP_LINK_TRAIN_400MV_6DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_600 | DP_TRAIN_PRE_EMPHASIS_6:
return EDP_LINK_TRAIN_400_600MV_6DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_600 | DP_TRAIN_PRE_EMPHASIS_3_5:
return EDP_LINK_TRAIN_600MV_3_5DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_800 | DP_TRAIN_PRE_EMPHASIS_3_5:
return EDP_LINK_TRAIN_600_800MV_3_5DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_800 | DP_TRAIN_PRE_EMPHASIS_0:
return EDP_LINK_TRAIN_800MV_0DB_SNB_B;
case DP_TRAIN_VOLTAGE_SWING_1200 | DP_TRAIN_PRE_EMPHASIS_0:
return EDP_LINK_TRAIN_800_1200MV_0DB_SNB_B;
default:
DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level\n");
return EDP_LINK_TRAIN_400MV_0DB_SNB_B;
DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level:"
"0x%x\n", signal_levels);
return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
}
}
......
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