Patch "drm/i915: apply the PCI_D0/D3 hibernation workaround everywhere on pre GEN6" has been added to the 4.2-stable tree

This is a note to let you know that I've just added the patch titled

drm/i915: apply the PCI_D0/D3 hibernation workaround everywhere on pre GEN6

to the 4.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
drm-i915-apply-the-pci_d0-d3-hibernation-workaround-everywhere-on-pre-gen6.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Imre Deak <[email protected]>
Date: Tue, 30 Jun 2015 17:06:47 +0300
Subject: drm/i915: apply the PCI_D0/D3 hibernation workaround everywhere on pre GEN6

From: Imre Deak <[email protected]>

commit 54875571bbfde00fc63741715c531cbb5246c3b2 upstream.

commit da2bc1b9db3351addd293e5b82757efe1f77ed1d

Author: Imre Deak <[email protected]>
Date:   Thu Oct 23 19:23:26 2014 +0300

drm/i915: add poweroff_late handler

introduced a regression on old platforms during hibernation. A workaround was added in

commit ab3be73fa7b43f4c3648ce29b5fd649ea54d3adb

Author: Imre Deak <[email protected]>
Date:   Mon Mar 2 13:04:41 2015 +0200

drm/i915: gen4: work around hang during hibernation

using an explicit blacklist for the GENs/BIOS vendors where the issue was reported. Later there we had reports of the same failure on platforms not on this list.

To my best knowledge the correct thing to do is still to put the device to PCI D3 state during hibernation, see [1] and [2] for the reasons. This also aligns with our future plans to unify more the runtime and system suspend/resume paths. Since an exact blacklist seems to be impractical (multiple GENs and BIOS vendors are affected) apply the workaround on everything pre GEN6.

[1] http://lists.freedesktop.org/archives/intel-gfx/2015-February/060710.html
[2] https://lkml.org/lkml/2015/6/22/274

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=95061

---
 drivers/gpu/drm/i915/i915_drv.c |   15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

@@ -683,15 +683,18 @@ static int i915_drm_suspend_late(struct
 
 	pci_disable_device(drm_dev->pdev);
 	/*
-	 * During hibernation on some GEN4 platforms the BIOS may try to access
+	 * During hibernation on some 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. Platforms where this was seen:
-	 * Lenovo Thinkpad X301, X61s
+	 * power down the device properly. The issue was seen on multiple old
+	 * GENs with different BIOS vendors, so having an explicit blacklist
+	 * is inpractical; apply the workaround on everything pre GEN6. The
+	 * platforms where the issue was seen:
+	 * Lenovo Thinkpad X301, X61s, X60, T60, X41
+	 * Fujitsu FSC S7110
+	 * Acer Aspire 1830T
 	 */
-	if (!(hibernation &&
-	      drm_dev->pdev->subsystem_vendor == PCI_VENDOR_ID_LENOVO &&
-	      INTEL_INFO(dev_priv)->gen == 4))
+	if (!(hibernation && INTEL_INFO(dev_priv)->gen < 6))
 		pci_set_power_state(drm_dev->pdev, PCI_D3hot);
 
 	return 0;

Patches currently in stable-queue which might be from [email protected] are

queue-4.2/drm-i915-apply-the-pci_d0-d3-hibernation-workaround-everywhere-on-pre-gen6.patch