From 4f7f7b7eb94bd37c449f06932459bbed78826f8d Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 18 Aug 2010 18:12:56 +0100 Subject: drm/i915/dp: Really try 5 times before giving up. Only stop trying if the aux channel sucessfully reports that the transmission was completed, otherwise try again. On the 5th failure, bail and report that something is amiss. This fixes a sporadic failure in reading the EDID for my external panel over DP. Signed-off-by: Chris Wilson Cc: stable@kernel.org --- drivers/gpu/drm/i915/intel_dp.c | 58 ++++++++++++++++++++--------------------- 1 file changed, 28 insertions(+), 30 deletions(-) (limited to 'drivers/gpu/drm/i915/intel_dp.c') diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 9caccd03dccb..51d142939a26 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -239,7 +239,6 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, uint32_t ch_data = ch_ctl + 4; int i; int recv_bytes; - uint32_t ctl; uint32_t status; uint32_t aux_clock_divider; int try, precharge; @@ -263,41 +262,43 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, else precharge = 5; + if (I915_READ(ch_ctl) & DP_AUX_CH_CTL_SEND_BUSY) { + DRM_ERROR("dp_aux_ch not started status 0x%08x\n", + I915_READ(ch_ctl)); + return -EBUSY; + } + /* 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) { - uint32_t d = pack_aux(send + i, send_bytes - i); - - I915_WRITE(ch_data + i, d); - } - - ctl = (DP_AUX_CH_CTL_SEND_BUSY | - 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); + 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, ctl); - (void) I915_READ(ch_ctl); + I915_WRITE(ch_ctl, + DP_AUX_CH_CTL_SEND_BUSY | + 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); for (;;) { - udelay(100); status = I915_READ(ch_ctl); if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0) break; + udelay(100); } /* 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)); - (void) I915_READ(ch_ctl); - if ((status & DP_AUX_CH_CTL_TIME_OUT_ERROR) == 0) + 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_DONE) break; } @@ -324,15 +325,12 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, /* Unload any bytes sent back from the other side */ recv_bytes = ((status & DP_AUX_CH_CTL_MESSAGE_SIZE_MASK) >> DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT); - if (recv_bytes > recv_size) recv_bytes = recv_size; - for (i = 0; i < recv_bytes; i += 4) { - uint32_t d = I915_READ(ch_data + i); - - unpack_aux(d, recv + i, recv_bytes - i); - } + for (i = 0; i < recv_bytes; i += 4) + unpack_aux(I915_READ(ch_data + i), + recv + i, recv_bytes - i); return recv_bytes; } -- cgit v1.2.2 From 7b334fcb45b757ffb093696ca3de1b0c8b4a33f1 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 9 Sep 2010 23:51:02 +0100 Subject: drm: Use a nondestructive mode for output detect when polling MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Destructive load-detection is very expensive and due to failings elsewhere can trigger system wide stalls of up to 600ms. A simple first step to correcting this is not to invoke such an expensive and destructive load-detection operation automatically. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29536 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=16265 Reported-by: Bruno Prémont Tested-by: Sitsofe Wheeler Signed-off-by: Chris Wilson Cc: stable@kernel.org Signed-off-by: Dave Airlie --- drivers/gpu/drm/i915/intel_dp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/i915/intel_dp.c') diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 51d142939a26..e1a2a05fb838 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1386,7 +1386,8 @@ ironlake_dp_detect(struct drm_connector *connector) * \return false if DP port is disconnected. */ static enum drm_connector_status -intel_dp_detect(struct drm_connector *connector) +intel_dp_detect(struct drm_connector *connector, + bool nondestructive) { struct drm_encoder *encoder = intel_attached_encoder(connector); struct intel_dp *intel_dp = enc_to_intel_dp(encoder); -- cgit v1.2.2 From 930a9e283516a3a3595c0c515113f1b78d07f695 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 14 Sep 2010 11:07:23 +0100 Subject: drm: Use a nondestructive mode for output detect when polling (v2) v2: Julien Cristau pointed out that @nondestructive results in double-negatives and confusion when trying to interpret the parameter, so use @force instead. Much easier to type as well. ;-) And fix the miscompilation of vmgfx reported by Sedat Dilek. Signed-off-by: Chris Wilson Cc: stable@kernel.org Signed-off-by: Dave Airlie --- drivers/gpu/drm/i915/intel_dp.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/gpu/drm/i915/intel_dp.c') diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index e1a2a05fb838..1a51ee07de3e 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1386,8 +1386,7 @@ ironlake_dp_detect(struct drm_connector *connector) * \return false if DP port is disconnected. */ static enum drm_connector_status -intel_dp_detect(struct drm_connector *connector, - bool nondestructive) +intel_dp_detect(struct drm_connector *connector, bool force) { struct drm_encoder *encoder = intel_attached_encoder(connector); struct intel_dp *intel_dp = enc_to_intel_dp(encoder); -- cgit v1.2.2