From 9f49c37635d5c2a801f7670d5fbf0b25ec461f2c Mon Sep 17 00:00:00 2001 From: Jesse Barnes Date: Wed, 10 Dec 2014 12:16:05 -0800 Subject: [PATCH] drm/i915: save/restore GMBUS freq across suspend/resume on gen4 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Should probably just init this in the GMbus code all the time, based on the cdclk and HPLL like we do on newer platforms. Ville has code for that in a rework branch, but until then we can fix this bug fairly easily. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76301 Signed-off-by: Jesse Barnes Reviewed-by: Ville Syrjälä Tested-by: Nikolay Cc: stable@vger.kernel.org Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/i915_suspend.c | 8 ++++++++ 3 files changed, 10 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index be910d2..63bcda5 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -924,6 +924,7 @@ struct i915_suspend_saved_registers { u32 savePIPEB_LINK_N1; u32 saveMCHBAR_RENDER_STANDBY; u32 savePCH_PORT_HOTPLUG; + u16 saveGCDGMBUS; }; struct vlv_s0ix_state { diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index b607bbe..eefdc23 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -85,6 +85,7 @@ #define I915_GC_RENDER_CLOCK_166_MHZ (0 << 0) #define I915_GC_RENDER_CLOCK_200_MHZ (1 << 0) #define I915_GC_RENDER_CLOCK_333_MHZ (4 << 0) +#define GCDGMBUS 0xcc #define PCI_LBPC 0xf4 /* legacy/combination backlight modes, also called LBB */ diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c index dfe6617..2636882 100644 --- a/drivers/gpu/drm/i915/i915_suspend.c +++ b/drivers/gpu/drm/i915/i915_suspend.c @@ -303,6 +303,10 @@ int i915_save_state(struct drm_device *dev) } } + if (IS_GEN4(dev)) + pci_read_config_word(dev->pdev, GCDGMBUS, + &dev_priv->regfile.saveGCDGMBUS); + /* Cache mode state */ if (INTEL_INFO(dev)->gen < 7) dev_priv->regfile.saveCACHE_MODE_0 = I915_READ(CACHE_MODE_0); @@ -331,6 +335,10 @@ int i915_restore_state(struct drm_device *dev) mutex_lock(&dev->struct_mutex); i915_gem_restore_fences(dev); + + if (IS_GEN4(dev)) + pci_write_config_word(dev->pdev, GCDGMBUS, + dev_priv->regfile.saveGCDGMBUS); i915_restore_display(dev); if (!drm_core_check_feature(dev, DRIVER_MODESET)) { -- 2.7.4