[Intel-gfx] [PATCH 11/15] drm/i915: PSR VLV/CHV: Introduce setup, enable and disable functions

Rodrigo Vivi rodrigo.vivi at gmail.com
Wed Nov 19 23:30:29 CET 2014


On Wed, Nov 19, 2014 at 11:22 AM, R, Durgadoss <durgadoss.r at intel.com> wrote:
>>-----Original Message-----
>>From: Rodrigo Vivi [mailto:rodrigo.vivi at gmail.com]
>>Sent: Wednesday, November 19, 2014 11:51 PM
>>To: R, Durgadoss
>>Cc: Vivi, Rodrigo; intel-gfx at lists.freedesktop.org
>>Subject: Re: [Intel-gfx] [PATCH 11/15] drm/i915: PSR VLV/CHV: Introduce setup, enable and disable
>>functions
>>
>>On Tue, Nov 18, 2014 at 10:32 AM, R, Durgadoss <durgadoss.r at intel.com> wrote:
>>>>-----Original Message-----
>>>>From: Vivi, Rodrigo
>>>>Sent: Friday, November 14, 2014 10:23 PM
>>>>To: intel-gfx at lists.freedesktop.org
>>>>Cc: Vivi, Rodrigo; R, Durgadoss
>>>>Subject: [PATCH 11/15] drm/i915: PSR VLV/CHV: Introduce setup, enable and disable functions
>>>>
>>>>The biggest difference from HSW/BDW PSR here is that VLV enable_source
>>>>function enables PSR but let it in Inactive state. So it might be called
>>>>on early stage along with setup and enable_sink ones.
>>>>
>>>>v2: Rebase over intel_psr.c;
>>>>    Remove docs from static functions;
>>>>    Merge vlv_psr_active_on_pipe;
>>>>    Timeout for psr transition is 250us;
>>>>    Remove SRC_TRASMITTER_STATE;
>>>
>>> With SRC_TRANSMITTER_STATE not set to 1
>>> explicitly, if entry/exit works, I would like to know what DPCD
>>> register 71h is reading in your panel ?
>>>
>>> I would expect bit 0 of 71h to be 1.
>>> Is it the case ?
>>
>>no. It is always 0.
>>
>>DP_PSR_CAPS = 0xA
>
> 0xA ? could be.. but surprising how exit works
> Without doing link training..
> May be we are looking at 01h..?, but your
> Description seems fine .. it is DP_PSR_CAPS.
> Can we double check once ?


+       u8 caps;
        drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG,
                           DP_PSR_ENABLE);
+
+       drm_dp_dpcd_readb(&intel_dp->aux, DP_PSR_CAPS,
+                          &caps);
+       DRM_ERROR("PSR Caps %x\n", caps);


The works part is that if I

+ drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_CAPS,
                          DP_PSR_NO_TRAIN_ON_EXIT);

and read again it is still 0xA

>
> eDP spec v1.3 claims default setup time is 330 us.
> So, I would expect bits[1:3] to be 0 (usually)
>
> This is the DPCD hex dump from 00h to 0xf in the
> Panels that I use: {from dmesg}
> DPCD: 11 0a 84 41 00 00 01 c0 02 03 00 00 00 0b 00

My one is

DPCD: 12 0a 82 41 00 00 01 80 02 00 00 00 0f 0b 00

and it is funny but even with different platforms and apparently
different panel I get the same... but maybe just a coincidence with
similar panels...

>
>>
>>> Can we check once ?
>>>
>>> Thanks,
>>> Durga
>>
>>What do you suggest? get SRC_TRANSMITTER_STATE back?
>
> Yes. The reason I say is because not all panels come with
> a 1 in that bit and ideally panels with a 0 in that bit 71h[0]
> are supposed to require link training after PSR exit
> when the main link is off. The main link will be off if we do
> not set the SRC_TRANSMITTER_STATE bit to 1.

Ok, I'm resending with SRC_TRANSMITTER_STATE back to 1.

>
> So, removing it is not safe in my opinion. I would suggest
> Keeping it there. And also, the same bit in the DPCD as well.

However I'm not sure about setting PSR_CAPS to 1 since my attempt here
still shows 0xA when reading it right after writing it.

>
> Thanks,
> Durga
>
>>
>>>
>>>>
>>>>Cc: Durgadoss R <durgadoss.r at intel.com>
>>>>Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
>>>>---
>>>> drivers/gpu/drm/i915/intel_psr.c | 154 ++++++++++++++++++++++++++++++++-------
>>>> 1 file changed, 129 insertions(+), 25 deletions(-)
>>>>
>>>>diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
>>>>index c296a89..bdb28f2 100644
>>>>--- a/drivers/gpu/drm/i915/intel_psr.c
>>>>+++ b/drivers/gpu/drm/i915/intel_psr.c
>>>>@@ -81,6 +81,17 @@ bool intel_psr_is_enabled(struct drm_device *dev)
>>>>       return (bool)dev_priv->psr.enabled;
>>>> }
>>>>
>>>>+static bool vlv_is_psr_active_on_pipe(struct drm_device *dev, int pipe)
>>>>+{
>>>>+      struct drm_i915_private *dev_priv = dev->dev_private;
>>>>+      uint32_t val;
>>>>+
>>>>+      val = I915_READ(VLV_PSRSTAT(pipe)) &
>>>>+            VLV_EDP_PSR_CURR_STATE_MASK;
>>>>+      return (val == VLV_EDP_PSR_ACTIVE_NORFB_UP) ||
>>>>+             (val == VLV_EDP_PSR_ACTIVE_SF_UPDATE);
>>>>+}
>>>>+
>>>> static void intel_psr_write_vsc(struct intel_dp *intel_dp,
>>>>                                   struct edp_vsc_psr *vsc_psr)
>>>> {
>>>>@@ -110,7 +121,23 @@ static void intel_psr_write_vsc(struct intel_dp *intel_dp,
>>>>       POSTING_READ(ctl_reg);
>>>> }
>>>>
>>>>-static void intel_psr_setup_vsc(struct intel_dp *intel_dp)
>>>>+static void vlv_psr_setup_vsc(struct intel_dp *intel_dp)
>>>>+{
>>>>+      struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
>>>>+      struct drm_device *dev = intel_dig_port->base.base.dev;
>>>>+      struct drm_i915_private *dev_priv = dev->dev_private;
>>>>+      struct drm_crtc *crtc = intel_dig_port->base.base.crtc;
>>>>+      enum pipe pipe = to_intel_crtc(crtc)->pipe;
>>>>+      uint32_t val;
>>>>+
>>>>+      /* VLV auto-generate VSC package as per EDP 1.3 spec, Table 3.10 */
>>>>+      val  = I915_READ(VLV_VSCSDP(pipe));
>>>>+      val &= ~VLV_EDP_PSR_SDP_FREQ_MASK;
>>>>+      val |= VLV_EDP_PSR_SDP_FREQ_EVFRAME;
>>>>+      I915_WRITE(VLV_VSCSDP(pipe), val);
>>>>+}
>>>>+
>>>>+static void hsw_psr_setup_vsc(struct intel_dp *intel_dp)
>>>> {
>>>>       struct edp_vsc_psr psr_vsc;
>>>>
>>>>@@ -123,7 +150,13 @@ static void intel_psr_setup_vsc(struct intel_dp *intel_dp)
>>>>       intel_psr_write_vsc(intel_dp, &psr_vsc);
>>>> }
>>>>
>>>>-static void intel_psr_enable_sink(struct intel_dp *intel_dp)
>>>>+static void vlv_psr_enable_sink(struct intel_dp *intel_dp)
>>>>+{
>>>>+      drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG,
>>>>+                         DP_PSR_ENABLE);
>>>>+}
>>>>+
>>>>+static void hsw_psr_enable_sink(struct intel_dp *intel_dp)
>>>> {
>>>>       struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
>>>>       struct drm_device *dev = dig_port->base.base.dev;
>>>>@@ -167,7 +200,21 @@ static void intel_psr_enable_sink(struct intel_dp *intel_dp)
>>>>                  (aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT));
>>>> }
>>>>
>>>>-static void intel_psr_enable_source(struct intel_dp *intel_dp)
>>>>+static void vlv_psr_enable_source(struct intel_dp *intel_dp)
>>>>+{
>>>>+      struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
>>>>+      struct drm_device *dev = dig_port->base.base.dev;
>>>>+      struct drm_i915_private *dev_priv = dev->dev_private;
>>>>+      struct drm_crtc *crtc = dig_port->base.base.crtc;
>>>>+      enum pipe pipe = to_intel_crtc(crtc)->pipe;
>>>>+
>>>>+      /* Transition from PSR_state 0 to PSR_state 1, i.e. PSR Inactive */
>>>>+      I915_WRITE(VLV_PSRCTL(pipe),
>>>>+                 VLV_EDP_PSR_MODE_SW_TIMER |
>>>>+                 VLV_EDP_PSR_ENABLE);
>>>>+}
>>>>+
>>>>+static void hsw_psr_enable_source(struct intel_dp *intel_dp)
>>>> {
>>>>       struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
>>>>       struct drm_device *dev = dig_port->base.base.dev;
>>>>@@ -247,7 +294,7 @@ static bool intel_psr_match_conditions(struct intel_dp *intel_dp)
>>>>       return true;
>>>> }
>>>>
>>>>-static void intel_psr_do_enable(struct intel_dp *intel_dp)
>>>>+static void intel_psr_activate(struct intel_dp *intel_dp)
>>>> {
>>>>       struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
>>>>       struct drm_device *dev = intel_dig_port->base.base.dev;
>>>>@@ -257,9 +304,12 @@ static void intel_psr_do_enable(struct intel_dp *intel_dp)
>>>>       WARN_ON(dev_priv->psr.active);
>>>>       lockdep_assert_held(&dev_priv->psr.lock);
>>>>
>>>>-      /* Enable/Re-enable PSR on the host */
>>>>-      intel_psr_enable_source(intel_dp);
>>>>-
>>>>+      /* Enable/Re-enable PSR on the host
>>>>+       * On HSW+ after we enable PSR on source it will activate it
>>>>+       * as soon as it match configure idle_frame count. So
>>>>+       * we just actually enable it here on activation time.
>>>>+       */
>>>>+      hsw_psr_enable_source(intel_dp);
>>>>       dev_priv->psr.active = true;
>>>> }
>>>>
>>>>@@ -296,37 +346,67 @@ void intel_psr_enable(struct intel_dp *intel_dp)
>>>>
>>>>       dev_priv->psr.busy_frontbuffer_bits = 0;
>>>>
>>>>-      intel_psr_setup_vsc(intel_dp);
>>>>+      if (HAS_DDI(dev)) {
>>>>+              hsw_psr_setup_vsc(intel_dp);
>>>>
>>>>-      /* Avoid continuous PSR exit by masking memup and hpd */
>>>>-      I915_WRITE(EDP_PSR_DEBUG_CTL(dev), EDP_PSR_DEBUG_MASK_MEMUP |
>>>>-                 EDP_PSR_DEBUG_MASK_HPD | EDP_PSR_DEBUG_MASK_LPSP);
>>>>+              /* Avoid continuous PSR exit by masking memup and hpd */
>>>>+              I915_WRITE(EDP_PSR_DEBUG_CTL(dev), EDP_PSR_DEBUG_MASK_MEMUP |
>>>>+                         EDP_PSR_DEBUG_MASK_HPD | EDP_PSR_DEBUG_MASK_LPSP);
>>>>
>>>>-      /* Enable PSR on the panel */
>>>>-      intel_psr_enable_sink(intel_dp);
>>>>+              /* Enable PSR on the panel */
>>>>+              hsw_psr_enable_sink(intel_dp);
>>>>+      } else {
>>>>+              vlv_psr_setup_vsc(intel_dp);
>>>>+
>>>>+              /* Enable PSR on the panel */
>>>>+              vlv_psr_enable_sink(intel_dp);
>>>>+
>>>>+              /* On HSW+ enable_source also means go to PSR entry/active
>>>>+               * state as soon as idle_frame achieved and here would be
>>>>+               * to soon. However on VLV enable_source just enable PSR
>>>>+               * but let it on inactive state. So we might do this prior
>>>>+               * to active transition, i.e. here.
>>>>+               */
>>>>+              vlv_psr_enable_source(intel_dp);
>>>>+      }
>>>>
>>>>       dev_priv->psr.enabled = intel_dp;
>>>> unlock:
>>>>       mutex_unlock(&dev_priv->psr.lock);
>>>> }
>>>>
>>>>-/**
>>>>- * intel_psr_disable - Disable PSR
>>>>- * @intel_dp: Intel DP
>>>>- *
>>>>- * This function needs to be called before disabling pipe.
>>>>- */
>>>>-void intel_psr_disable(struct intel_dp *intel_dp)
>>>>+static void vlv_psr_disable(struct intel_dp *intel_dp)
>>>> {
>>>>       struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
>>>>       struct drm_device *dev = intel_dig_port->base.base.dev;
>>>>       struct drm_i915_private *dev_priv = dev->dev_private;
>>>>+      struct intel_crtc *intel_crtc =
>>>>+              to_intel_crtc(intel_dig_port->base.base.crtc);
>>>>+      uint32_t val;
>>>>
>>>>-      mutex_lock(&dev_priv->psr.lock);
>>>>-      if (!dev_priv->psr.enabled) {
>>>>-              mutex_unlock(&dev_priv->psr.lock);
>>>>-              return;
>>>>+      if (dev_priv->psr.active) {
>>>>+              /* Put VLV PSR back to PSR_state 0 that is PSR Disabled. */
>>>>+              if (wait_for((I915_READ(VLV_PSRSTAT(intel_crtc->pipe)) &
>>>>+                            VLV_EDP_PSR_IN_TRANS) == 0, 0.250))
>>>>+                      WARN(1, "PSR transition took longer than expected\n");
>>>>+
>>>>+              val = I915_READ(VLV_PSRCTL(intel_crtc->pipe));
>>>>+              val &= ~VLV_EDP_PSR_ACTIVE_ENTRY;
>>>>+              val &= ~VLV_EDP_PSR_ENABLE;
>>>>+              val &= ~VLV_EDP_PSR_MODE_MASK;
>>>>+              I915_WRITE(VLV_PSRCTL(intel_crtc->pipe), val);
>>>>+
>>>>+              dev_priv->psr.active = false;
>>>>+      } else {
>>>>+              WARN_ON(vlv_is_psr_active_on_pipe(dev, intel_crtc->pipe));
>>>>       }
>>>>+}
>>>>+
>>>>+static void hsw_psr_disable(struct intel_dp *intel_dp)
>>>>+{
>>>>+      struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
>>>>+      struct drm_device *dev = intel_dig_port->base.base.dev;
>>>>+      struct drm_i915_private *dev_priv = dev->dev_private;
>>>>
>>>>       if (dev_priv->psr.active) {
>>>>               I915_WRITE(EDP_PSR_CTL(dev),
>>>>@@ -341,6 +421,30 @@ void intel_psr_disable(struct intel_dp *intel_dp)
>>>>       } else {
>>>>               WARN_ON(I915_READ(EDP_PSR_CTL(dev)) & EDP_PSR_ENABLE);
>>>>       }
>>>>+}
>>>>+
>>>>+/**
>>>>+ * intel_psr_disable - Disable PSR
>>>>+ * @intel_dp: Intel DP
>>>>+ *
>>>>+ * This function needs to be called before disabling pipe.
>>>>+ */
>>>>+void intel_psr_disable(struct intel_dp *intel_dp)
>>>>+{
>>>>+      struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
>>>>+      struct drm_device *dev = intel_dig_port->base.base.dev;
>>>>+      struct drm_i915_private *dev_priv = dev->dev_private;
>>>>+
>>>>+      mutex_lock(&dev_priv->psr.lock);
>>>>+      if (!dev_priv->psr.enabled) {
>>>>+              mutex_unlock(&dev_priv->psr.lock);
>>>>+              return;
>>>>+      }
>>>>+
>>>>+      if (HAS_DDI(dev))
>>>>+              hsw_psr_disable(intel_dp);
>>>>+      else
>>>>+              vlv_psr_disable(intel_dp);
>>>>
>>>>       dev_priv->psr.enabled = NULL;
>>>>       mutex_unlock(&dev_priv->psr.lock);
>>>>@@ -379,7 +483,7 @@ static void intel_psr_work(struct work_struct *work)
>>>>       if (dev_priv->psr.busy_frontbuffer_bits)
>>>>               goto unlock;
>>>>
>>>>-      intel_psr_do_enable(intel_dp);
>>>>+      intel_psr_activate(intel_dp);
>>>> unlock:
>>>>       mutex_unlock(&dev_priv->psr.lock);
>>>> }
>>>>--
>>>>1.9.3
>>>
>>> _______________________________________________
>>> Intel-gfx mailing list
>>> Intel-gfx at lists.freedesktop.org
>>> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>>
>>
>>
>>--
>>Rodrigo Vivi
>>Blog: http://blog.vivi.eng.br



-- 
Rodrigo Vivi
Blog: http://blog.vivi.eng.br



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