On Mon, 8 Aug 2011 13:01:28 -0700, Jesse Barnes jbarnes@virtuousgeek.org wrote:
On Mon, 08 Aug 2011 12:53:31 -0700 Keith Packard keithp@keithp.com wrote:
On Mon, 8 Aug 2011 11:49:54 -0700, Jesse Barnes jbarnes@virtuousgeek.org wrote:
Yep, it's safe and possible to do on pre-PCH as well. For panel fitting we do need to do an actual power cycle when going from non-native back to native iirc, but we can still leave them unlocked so we don't have to worry about the lock/unlock sequence everywhere.
Hidden in the unlock patch was a call to intel_lvds_disable from intel_lvds_prepare -- that *always* turns off the LVDS for mode setting. Do we care enough about LVDS mode setting performance that we should try leave the optimization in place that doesn't turn off the backlight when switching between modes?
We hate flicker right? But generally yes it's safer to just turn it off all the time.
I'll leave the optimization in place then; it's been there for a while so at least it shouldn't cause any regressions.
How about this? Has the advantage of not lying in the commit message anymore.
From 092719152aa5a235d6678798a34dc784d5cec2ad Mon Sep 17 00:00:00 2001 From: Keith Packard keithp@keithp.com Date: Sat, 6 Aug 2011 10:33:12 -0700 Subject: [PATCH 2/5] drm/i915: Leave LVDS registers unlocked
There's no reason to relock them; it just makes operations more complex. This fixes DPMS where the panel registers were locked making the disable not work.
Signed-off-by: Keith Packard keithp@keithp.com --- drivers/gpu/drm/i915/intel_lvds.c | 51 +++++++++++------------------------- 1 files changed, 16 insertions(+), 35 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c index 6318828..8b521a2 100644 --- a/drivers/gpu/drm/i915/intel_lvds.c +++ b/drivers/gpu/drm/i915/intel_lvds.c @@ -400,53 +400,21 @@ out:
static void intel_lvds_prepare(struct drm_encoder *encoder) { - struct drm_device *dev = encoder->dev; - struct drm_i915_private *dev_priv = dev->dev_private; struct intel_lvds *intel_lvds = to_intel_lvds(encoder);
- /* We try to do the minimum that is necessary in order to unlock - * the registers for mode setting. - * - * On Ironlake, this is quite simple as we just set the unlock key - * and ignore all subtleties. (This may cause some issues...) - * + /* * Prior to Ironlake, we must disable the pipe if we want to adjust * the panel fitter. However at all other times we can just reset * the registers regardless. */ - - if (HAS_PCH_SPLIT(dev)) { - I915_WRITE(PCH_PP_CONTROL, - I915_READ(PCH_PP_CONTROL) | PANEL_UNLOCK_REGS); - } else if (intel_lvds->pfit_dirty) { - I915_WRITE(PP_CONTROL, - (I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS) - & ~POWER_TARGET_ON); - } else { - I915_WRITE(PP_CONTROL, - I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS); - } + if (!HAS_PCH_SPLIT(encoder->dev) && intel_lvds->pfit_dirty) + intel_lvds_disable(intel_lvds); }
static void intel_lvds_commit(struct drm_encoder *encoder) { - struct drm_device *dev = encoder->dev; - struct drm_i915_private *dev_priv = dev->dev_private; struct intel_lvds *intel_lvds = to_intel_lvds(encoder);
- /* Undo any unlocking done in prepare to prevent accidental - * adjustment of the registers. - */ - if (HAS_PCH_SPLIT(dev)) { - u32 val = I915_READ(PCH_PP_CONTROL); - if ((val & PANEL_UNLOCK_REGS) == PANEL_UNLOCK_REGS) - I915_WRITE(PCH_PP_CONTROL, val & 0x3); - } else { - u32 val = I915_READ(PP_CONTROL); - if ((val & PANEL_UNLOCK_REGS) == PANEL_UNLOCK_REGS) - I915_WRITE(PP_CONTROL, val & 0x3); - } - /* Always do a full power on as we do not know what state * we were left in. */ @@ -1042,6 +1010,19 @@ out: pwm = I915_READ(BLC_PWM_PCH_CTL1); pwm |= PWM_PCH_ENABLE; I915_WRITE(BLC_PWM_PCH_CTL1, pwm); + /* + * Unlock registers and just + * leave them unlocked + */ + I915_WRITE(PCH_PP_CONTROL, + I915_READ(PCH_PP_CONTROL) | PANEL_UNLOCK_REGS); + } else { + /* + * Unlock registers and just + * leave them unlocked + */ + I915_WRITE(PP_CONTROL, + I915_READ(PP_CONTROL) | PANEL_UNLOCK_REGS); } dev_priv->lid_notifier.notifier_call = intel_lid_notify; if (acpi_lid_notifier_register(&dev_priv->lid_notifier)) {