From 5c23657bc168db12a1ba100ab65fabd305c89c8a Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Thu, 26 Feb 2015 18:38:53 +0200 Subject: [PATCH] drm/i915: gm45: work around hang during hibernation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Bjørn reported that his machine hang during hibernation and eventually bisected the problem to the following commit: commit da2bc1b9db3351addd293e5b82757efe1f77ed1d Author: Imre Deak Date: Thu Oct 23 19:23:26 2014 +0300 drm/i915: add poweroff_late handler The problem seems to be that after the kernel puts the device into D3 the BIOS still tries to access it, or otherwise assumes that it's in D0. This is clearly bogus, since ACPI mandates that devices are put into D3 by the OSPM if they are not wake-up sources. In the future we want to unify more of the driver's runtime and system suspend paths, for example by skipping all the system suspend/hibernation hooks if the device is runtime suspended already. Accordingly for all other platforms the goal is still to properly power down the device during hibernation. Reference: http://lists.freedesktop.org/archives/intel-gfx/2015-February/060633.html Reported-and-bisected-by: Bjørn Mork Signed-off-by: Imre Deak --- drivers/gpu/drm/i915/i915_drv.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 4badb23..67d212b 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -637,7 +637,7 @@ static int i915_drm_suspend(struct drm_device *dev) return 0; } -static int i915_drm_suspend_late(struct drm_device *drm_dev) +static int i915_drm_suspend_late(struct drm_device *drm_dev, bool hibernation) { struct drm_i915_private *dev_priv = drm_dev->dev_private; int ret; @@ -651,7 +651,14 @@ static int i915_drm_suspend_late(struct drm_device *drm_dev) } pci_disable_device(drm_dev->pdev); - pci_set_power_state(drm_dev->pdev, PCI_D3hot); + /* + * During hibernation on some GM45 platforms the BIOS may try to access + * the device even though it's already in D3 and hang the machine. So + * leave the device in D0 on those platforms and hope the BIOS will + * power down the device properly. + */ + if (!(hibernation && IS_GM45(dev_priv))) + pci_set_power_state(drm_dev->pdev, PCI_D3hot); return 0; } @@ -677,7 +684,7 @@ int i915_suspend_legacy(struct drm_device *dev, pm_message_t state) if (error) return error; - return i915_drm_suspend_late(dev); + return i915_drm_suspend_late(dev, false); } static int i915_drm_resume(struct drm_device *dev) @@ -965,7 +972,17 @@ static int i915_pm_suspend_late(struct device *dev) if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF) return 0; - return i915_drm_suspend_late(drm_dev); + return i915_drm_suspend_late(drm_dev, false); +} + +static int i915_pm_poweroff_late(struct device *dev) +{ + struct drm_device *drm_dev = dev_to_i915(dev)->dev; + + if (drm_dev->switch_power_state == DRM_SWITCH_POWER_OFF) + return 0; + + return i915_drm_suspend_late(drm_dev, true); } static int i915_pm_resume_early(struct device *dev) @@ -1535,7 +1552,7 @@ static const struct dev_pm_ops i915_pm_ops = { .thaw_early = i915_pm_resume_early, .thaw = i915_pm_resume, .poweroff = i915_pm_suspend, - .poweroff_late = i915_pm_suspend_late, + .poweroff_late = i915_pm_poweroff_late, .restore_early = i915_pm_resume_early, .restore = i915_pm_resume, -- 2.1.0