Commit bc86625a authored by Chris Wilson's avatar Chris Wilson Committed by Daniel Vetter

drm/i915: Retry DP aux_ch communications with a different clock after failure

The w/a db makes the recommendation to both use a non-default value for
the initial clock and then to retry with an alternative clock for
Haswell with the Lakeport PCH.

"On LPT:H, use a divider value of 63 decimal (03Fh). If there is a
failure, retry at least three times with 63, then retry at least three
times with 72 decimal (048h)."
Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: default avatarJani Nikula <jani.nikula@intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent b8f102e8
......@@ -276,7 +276,8 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
return status;
}
static uint32_t get_aux_clock_divider(struct intel_dp *intel_dp)
static uint32_t get_aux_clock_divider(struct intel_dp *intel_dp,
int index)
{
struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
struct drm_device *dev = intel_dig_port->base.base.dev;
......@@ -290,22 +291,27 @@ static uint32_t get_aux_clock_divider(struct intel_dp *intel_dp)
* clock divider.
*/
if (IS_VALLEYVIEW(dev)) {
return 100;
return index ? 0 : 100;
} else if (intel_dig_port->port == PORT_A) {
if (index)
return 0;
if (HAS_DDI(dev))
return DIV_ROUND_CLOSEST(
intel_ddi_get_cdclk_freq(dev_priv), 2000);
return DIV_ROUND_CLOSEST(intel_ddi_get_cdclk_freq(dev_priv), 2000);
else if (IS_GEN6(dev) || IS_GEN7(dev))
return 200; /* SNB & IVB eDP input clock at 400Mhz */
else
return 225; /* eDP input clock at 450Mhz */
} else if (dev_priv->pch_id == INTEL_PCH_LPT_DEVICE_ID_TYPE) {
/* Workaround for non-ULT HSW */
return 74;
switch (index) {
case 0: return 63;
case 1: return 72;
default: return 0;
}
} else if (HAS_PCH_SPLIT(dev)) {
return DIV_ROUND_UP(intel_pch_rawclk(dev), 2);
return index ? 0 : DIV_ROUND_UP(intel_pch_rawclk(dev), 2);
} else {
return intel_hrawclk(dev) / 2;
return index ? 0 :intel_hrawclk(dev) / 2;
}
}
......@@ -319,10 +325,10 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
struct drm_i915_private *dev_priv = dev->dev_private;
uint32_t ch_ctl = intel_dp->aux_ch_ctl_reg;
uint32_t ch_data = ch_ctl + 4;
uint32_t aux_clock_divider;
int i, ret, recv_bytes;
uint32_t status;
uint32_t aux_clock_divider = get_aux_clock_divider(intel_dp);
int try, precharge;
int try, precharge, clock = 0;
bool has_aux_irq = INTEL_INFO(dev)->gen >= 5 && !IS_VALLEYVIEW(dev);
/* dp aux is extremely sensitive to irq latency, hence request the
......@@ -353,37 +359,41 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
goto out;
}
/* Must try at least 3 times according to DP spec */
for (try = 0; try < 5; try++) {
/* Load the send data into the aux channel data registers */
for (i = 0; i < send_bytes; i += 4)
I915_WRITE(ch_data + i,
pack_aux(send + i, send_bytes - i));
/* Send the command and wait for it to complete */
I915_WRITE(ch_ctl,
DP_AUX_CH_CTL_SEND_BUSY |
(has_aux_irq ? DP_AUX_CH_CTL_INTERRUPT : 0) |
DP_AUX_CH_CTL_TIME_OUT_400us |
(send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
(precharge << DP_AUX_CH_CTL_PRECHARGE_2US_SHIFT) |
(aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT) |
DP_AUX_CH_CTL_DONE |
DP_AUX_CH_CTL_TIME_OUT_ERROR |
DP_AUX_CH_CTL_RECEIVE_ERROR);
status = intel_dp_aux_wait_done(intel_dp, has_aux_irq);
/* Clear done status and any errors */
I915_WRITE(ch_ctl,
status |
DP_AUX_CH_CTL_DONE |
DP_AUX_CH_CTL_TIME_OUT_ERROR |
DP_AUX_CH_CTL_RECEIVE_ERROR);
if (status & (DP_AUX_CH_CTL_TIME_OUT_ERROR |
DP_AUX_CH_CTL_RECEIVE_ERROR))
continue;
while ((aux_clock_divider = get_aux_clock_divider(intel_dp, clock++))) {
/* Must try at least 3 times according to DP spec */
for (try = 0; try < 5; try++) {
/* Load the send data into the aux channel data registers */
for (i = 0; i < send_bytes; i += 4)
I915_WRITE(ch_data + i,
pack_aux(send + i, send_bytes - i));
/* Send the command and wait for it to complete */
I915_WRITE(ch_ctl,
DP_AUX_CH_CTL_SEND_BUSY |
(has_aux_irq ? DP_AUX_CH_CTL_INTERRUPT : 0) |
DP_AUX_CH_CTL_TIME_OUT_400us |
(send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
(precharge << DP_AUX_CH_CTL_PRECHARGE_2US_SHIFT) |
(aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT) |
DP_AUX_CH_CTL_DONE |
DP_AUX_CH_CTL_TIME_OUT_ERROR |
DP_AUX_CH_CTL_RECEIVE_ERROR);
status = intel_dp_aux_wait_done(intel_dp, has_aux_irq);
/* Clear done status and any errors */
I915_WRITE(ch_ctl,
status |
DP_AUX_CH_CTL_DONE |
DP_AUX_CH_CTL_TIME_OUT_ERROR |
DP_AUX_CH_CTL_RECEIVE_ERROR);
if (status & (DP_AUX_CH_CTL_TIME_OUT_ERROR |
DP_AUX_CH_CTL_RECEIVE_ERROR))
continue;
if (status & DP_AUX_CH_CTL_DONE)
break;
}
if (status & DP_AUX_CH_CTL_DONE)
break;
}
......@@ -1453,7 +1463,7 @@ static void intel_edp_psr_enable_sink(struct intel_dp *intel_dp)
{
struct drm_device *dev = intel_dp_to_dev(intel_dp);
struct drm_i915_private *dev_priv = dev->dev_private;
uint32_t aux_clock_divider = get_aux_clock_divider(intel_dp);
uint32_t aux_clock_divider = get_aux_clock_divider(intel_dp, 0);
int precharge = 0x3;
int msg_size = 5; /* Header(4) + Message(1) */
......
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