This is a note to let you know that I've just added the patch titled
drm/i915: Retry DP aux_ch communications with a different clock after failure
to the 3.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-i915-retry-dp-aux_ch-communications-with-a-different-clock-after-failure.patch
and it can be found in the queue-3.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From bc86625a4ff7574d4d4dba79723457711eb784e0 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Date: Sun, 21 Jul 2013 16:00:03 +0100
Subject: drm/i915: Retry DP aux_ch communications with a different clock after failure
From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
commit bc86625a4ff7574d4d4dba79723457711eb784e0 upstream.
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: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/intel_dp.c | 90 ++++++++++++++++++++++------------------
1 file changed, 50 insertions(+), 40 deletions(-)
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -276,7 +276,8 @@ intel_dp_aux_wait_done(struct intel_dp *
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(st
* 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_d
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_d
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;
}
Patches currently in stable-queue which might be from chris@xxxxxxxxxxxxxxxxxx are
queue-3.11/drm-i915-retry-dp-aux_ch-communications-with-a-different-clock-after-failure.patch
queue-3.11/drm-prevent-overwriting-from-userspace-underallocating-core-ioctl-structs.patch
queue-3.11/drm-pad-drm_mode_get_connector-to-64-bit-boundary.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html