On Tue, Aug 28, 2012 at 03:56:31PM +0200, Indan Zupancic wrote: > Hello, > > On Tue, August 28, 2012 08:53, Jani Nikula wrote: > > From: Daniel Vetter <daniel.vetter at ffwll.ch> > > > > This is a prep patch to stop drm/i915 from changing the LBPC registers > > itself - but we still need to properly save/restore it on > > suspend/resume. > > > > Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch> > > Signed-off-by: Jani Nikula <jani.nikula at intel.com> > > --- > > drivers/gpu/drm/i915/i915_drv.h | 1 + > > drivers/gpu/drm/i915/i915_reg.h | 3 +++ > > drivers/gpu/drm/i915/i915_suspend.c | 8 ++++++++ > > drivers/gpu/drm/i915/intel_panel.c | 2 -- > > 4 files changed, 12 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h > > index 58b43db..af1701c 100644 > > --- a/drivers/gpu/drm/i915/i915_drv.h > > +++ b/drivers/gpu/drm/i915/i915_drv.h > > @@ -606,6 +606,7 @@ typedef struct drm_i915_private { > > u32 savePP_CONTROL; > > u32 savePP_DIVISOR; > > u32 savePFIT_CONTROL; > > + u8 saveLBPC; > > u32 save_palette_a[256]; > > u32 save_palette_b[256]; > > u32 saveDPFC_CB_BASE; > > diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h > > index d0b60f2..3303c18 100644 > > --- a/drivers/gpu/drm/i915/i915_reg.h > > +++ b/drivers/gpu/drm/i915/i915_reg.h > > @@ -1889,6 +1889,9 @@ > > > > #define PFIT_AUTO_RATIOS 0x61238 > > > > +/* legacy/combination backlight modes in pci config space. */ > > +#define PCI_LBPC 0xf4 > > + > > /* Backlight control */ > > #define BLC_PWM_CTL2 0x61250 /* 965+ only */ > > #define BLM_PWM_ENABLE (1 << 31) > > diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c > > index 4776ccf..05daff7 100644 > > --- a/drivers/gpu/drm/i915/i915_suspend.c > > +++ b/drivers/gpu/drm/i915/i915_suspend.c > > @@ -639,6 +639,10 @@ static void i915_save_display(struct drm_device *dev) > > dev_priv->saveBLC_PWM_CTL2 = I915_READ(BLC_PWM_CTL2); > > if (IS_MOBILE(dev) && !IS_I830(dev)) > > dev_priv->saveLVDS = I915_READ(LVDS); > > + > > + if (IS_GEN2(dev) || IS_GEN4(dev)) > > + pci_read_config_byte(dev->pdev, PCI_LBPC, > > + &dev_priv->saveLBPC); > > What about GEN3? > > It seems weird that LBPC wouldn't be restored during resume by some BIOSes, > is this really necessary? ba3820ade317ee36e496b9b40d2ec3987dd4aef0 claims so. But that commit managed to put too many things into the same thing unfortunately. -Daniel -- Daniel Vetter Mail: daniel at ffwll.ch Mobile: +41 (0)79 365 57 48