[Intel-gfx] [PATCH 04/10] drm/i915: PSR VLV/CHV: Introduce setup, enable and disable functions

Rodrigo Vivi rodrigo.vivi at gmail.com
Fri Nov 14 01:33:21 CET 2014


On Thu, Nov 6, 2014 at 1:32 PM, R, Durgadoss <durgadoss.r at intel.com> wrote:
>>-----Original Message-----
>>From: Intel-gfx [mailto:intel-gfx-bounces at lists.freedesktop.org] On Behalf Of
>>Rodrigo Vivi
>>Sent: Wednesday, October 29, 2014 12:16 AM
>>To: intel-gfx at lists.freedesktop.org
>>Cc: Vivi, Rodrigo
>>Subject: [Intel-gfx] [PATCH 04/10] 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.
>>
>>Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
>>---
>> drivers/gpu/drm/i915/intel_dp.c | 161
>>++++++++++++++++++++++++++++++++++++----
>> 1 file changed, 145 insertions(+), 16 deletions(-)
>>
>>diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>>index ac70b3a..335a711 100644
>>--- a/drivers/gpu/drm/i915/intel_dp.c
>>+++ b/drivers/gpu/drm/i915/intel_dp.c
>>@@ -2134,7 +2134,44 @@ static void intel_edp_psr_write_vsc(struct intel_dp
>>*intel_dp,
>>       POSTING_READ(ctl_reg);
>> }
>>
>>-static void intel_edp_psr_setup_vsc(struct intel_dp *intel_dp)
>>+/**
>>+ * vlv_edp_psr_setup_vsc - Setup PSR related VSC aux registers on VLV+.
>>+ * @intel_dp: DP struct
>>+ *
>>+ * On VLV we don't need to generate VSC. It auto generates according
>>+ * EDP 1.3 spec, Table 3.10.
>>+ * HB0   - Secondary Data Packet ID = 0
>>+ * HB1   - Secondary Data Packet Type = 07h
>>+ * HB2   - Bits 4:0 = Revision Number = 02h
>>+ *         Bits 7:5 = Reserved (all 0s)
>>+ * HB3   - Bits 4:0 Number of Valid Data Bytes = 08h
>>+ *         Bits 7:5 Reserved
>>+ * DB0   - Bits 7:4 Stereo Interface Method Specific Paramenter
>>+ *         Bits 3:0 Stereo Interface Method Code
>>+ * DB1   - Bit 0 - PSR State (0 when Inactive / 1 when Active)
>>+ *         Bit 1 - Update RFB. (0 do not update RFB / 1 update RFB)
>>+ *         Bit 2 - CRC Valid. VLV always send 0 which
>>+ *                            means CRC value in DB7:2 invalid
>>+ *         Bits 7:3 - Reserved
>>+ * DB2-7 - CRC - don't care because DB1[2] always tells this is invalid.
>>+ */
>>+static void vlv_edp_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_edp_psr_setup_vsc(struct intel_dp *intel_dp)
>> {
>>       struct edp_vsc_psr psr_vsc;
>>
>>@@ -2147,7 +2184,20 @@ static void intel_edp_psr_setup_vsc(struct intel_dp
>>*intel_dp)
>>       intel_edp_psr_write_vsc(intel_dp, &psr_vsc);
>> }
>>
>>-static void intel_edp_psr_enable_sink(struct intel_dp *intel_dp)
>>+/**
>>+ * vlv_edp_psr_enable_sink - Enable PSR on Panel for VLV.
>>+ * @intel_dp: DP struct
>>+ *
>>+ * This function enable PSR on Panel (Sink) side over DPCD write.
>>+ */
>>+static void vlv_edp_psr_enable_sink(struct intel_dp *intel_dp)
>>+{
>>+      /* Enable PSR in sink */
>>+      drm_dp_dpcd_writeb(&intel_dp->aux, DP_PSR_EN_CFG,
>>+                         DP_PSR_ENABLE);
>>+}
>>+
>>+static void hsw_edp_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;
>>@@ -2191,7 +2241,28 @@ static void intel_edp_psr_enable_sink(struct intel_dp
>>*intel_dp)
>>                  (aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT));
>> }
>>
>>-static void intel_edp_psr_enable_source(struct intel_dp *intel_dp)
>>+/**
>>+ * vlv_edp_psr_enable_source - Enable PSR on VLV without activate it.
>>+ * @intel_dp: DP struct
>>+ *
>>+ * This function do the transition from PSR_state 0 to PSR_state 1 that is
>>+ * PSR Inactive one..
>>+ */
>>+static void vlv_edp_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;
>>+
>>+      I915_WRITE(VLV_PSRCTL(pipe),
>>+                 VLV_EDP_PSR_SRC_TRANSMITTER_STATE |
>
> I see we are keeping the source active during PSR.
> Making this '0' may provide better power savings,
> but we need to manage a lot of hassle during PSR exit..
> (like Link training, DPIO/PLL bring up etc..)

Also I think this blocked sink crc to work. So we wouldn't be able to
validate it.
Although there are other things blocking that tests :(
But I can double check that anyway.

>
>>+                 VLV_EDP_PSR_MODE_SW_TIMER |
>>+                 VLV_EDP_PSR_ENABLE);
>>+}
>>+
>>+static void hsw_edp_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;
>>@@ -2276,7 +2347,7 @@ static void intel_edp_psr_do_enable(struct intel_dp
>>*intel_dp)
>>       lockdep_assert_held(&dev_priv->psr.lock);
>>
>>       /* Enable/Re-enable PSR on the host */
>>-      intel_edp_psr_enable_source(intel_dp);
>>+      hsw_edp_psr_enable_source(intel_dp);
>>
>>       dev_priv->psr.active = true;
>> }
>>@@ -2307,30 +2378,71 @@ void intel_edp_psr_enable(struct intel_dp *intel_dp)
>>
>>       dev_priv->psr.busy_frontbuffer_bits = 0;
>>
>>-      intel_edp_psr_setup_vsc(intel_dp);
>>+      if (HAS_DDI(dev)) {
>>+              hsw_edp_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 */
>>+              hsw_edp_psr_enable_sink(intel_dp);
>>+      } else {
>>+              vlv_edp_psr_setup_vsc(intel_dp);
>>
>>-      /* Enable PSR on the panel */
>>-      intel_edp_psr_enable_sink(intel_dp);
>>+              /* Enable PSR on the panel */
>>+              vlv_edp_psr_enable_sink(intel_dp);
>>+
>>+              /* On HSW/BDW 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_edp_psr_enable_source(intel_dp);
>>+      }
>>
>>       dev_priv->psr.enabled = intel_dp;
>> unlock:
>>       mutex_unlock(&dev_priv->psr.lock);
>> }
>>
>>-void intel_edp_psr_disable(struct intel_dp *intel_dp)
>>+/**
>>+ * vlv_edp_psr_disable - Disable PSR on VLV
>>+ * @intel_dp: DP struct
>>+ *
>>+ * This function puts PSR VLV back to PSR_state 0 that is PSR Disabled.
>
> I hope you meant 'puts VLV PSR'..

Yes thanks!

>
>>+ */
>>+static void vlv_edp_psr_disable(struct intel_dp *intel_dp)
>> {
>>-      struct drm_device *dev = intel_dp_to_dev(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) {
>>+              if (wait_for((I915_READ(VLV_PSRSTAT(intel_crtc->pipe)) &
>>+                            VLV_EDP_PSR_IN_TRANS) == 0, 250))
>>+                      WARN(1, "PSR transition took longer than expected\n");
>
> The spec claims this waiting time as 250 micro seconds.
> Looks like we are waiting for 250 ms.. No ?

This is true. I'll fix that and test tomorrow.

>
> Just curious, did you see this transition during testing ?

No, I never checked.

>
> Thanks,
> Durga
>
>>+
>>+              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_edp_is_psr_enabled_on_pipe(dev, intel_crtc-
>>>pipe));
>>       }
>>+}
>>+
>>+static void hsw_edp_psr_disable(struct intel_dp *intel_dp)
>>+{
>>+      struct drm_device *dev = intel_dp_to_dev(intel_dp);
>>+      struct drm_i915_private *dev_priv = dev->dev_private;
>>
>>       if (dev_priv->psr.active) {
>>               I915_WRITE(EDP_PSR_CTL(dev),
>>@@ -2345,6 +2457,23 @@ void intel_edp_psr_disable(struct intel_dp *intel_dp)
>>       } else {
>>               WARN_ON(I915_READ(EDP_PSR_CTL(dev)) & EDP_PSR_ENABLE);
>>       }
>>+}
>>+
>>+void intel_edp_psr_disable(struct intel_dp *intel_dp)
>>+{
>>+      struct drm_device *dev = intel_dp_to_dev(intel_dp);
>>+      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_edp_psr_disable(intel_dp);
>>+      else
>>+              vlv_edp_psr_disable(intel_dp);
>>
>>       dev_priv->psr.enabled = NULL;
>>       mutex_unlock(&dev_priv->psr.lock);
>>--
>>1.9.3
>>
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-- 
Rodrigo Vivi
Blog: http://blog.vivi.eng.br



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