Patch "drm/i915: Only enable hotplug interrupts if the display interrupts are enabled" has been added to the 4.10-stable tree

Patch "drm/i915: Only enable hotplug interrupts if the display interrupts are enabled" has been added to the 4.10-stable tree

[gregkh]

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

    drm/i915: Only enable hotplug interrupts if the display interrupts are enabled

to the 4.10-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-only-enable-hotplug-interrupts-if-the-display-interrupts-are-enabled.patch
and it can be found in the queue-4.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 35a3abfd198e6c69a6644784bb09a2d951fc6b21 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Mon, 13 Mar 2017 17:02:31 +0000
Subject: drm/i915: Only enable hotplug interrupts if the display interrupts are enabled
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Chris Wilson <chris@chris-wilson.co.uk>

commit 35a3abfd198e6c69a6644784bb09a2d951fc6b21 upstream.

In order to prevent accessing the hpd registers outside of the display
power wells, we should refrain from writing to the registers before the
display interrupts are enabled.

[    4.740136] WARNING: CPU: 1 PID: 221 at drivers/gpu/drm/i915/intel_uncore.c:795 __unclaimed_reg_debug+0x44/0x50 [i915]
[    4.740155] Unclaimed read from register 0x1e1110
[    4.740168] Modules linked in: i915(+) intel_gtt drm_kms_helper prime_numbers
[    4.740190] CPU: 1 PID: 221 Comm: systemd-udevd Not tainted 4.10.0-rc6+ #384
[    4.740203] Hardware name:                  /        , BIOS PYBSWCEL.86A.0027.2015.0507.1758 05/07/2015
[    4.740220] Call Trace:
[    4.740236]  dump_stack+0x4d/0x6f
[    4.740251]  __warn+0xc1/0xe0
[    4.740265]  warn_slowpath_fmt+0x4a/0x50
[    4.740281]  ? insert_work+0x77/0xc0
[    4.740355]  ? fwtable_write32+0x90/0x130 [i915]
[    4.740431]  __unclaimed_reg_debug+0x44/0x50 [i915]
[    4.740507]  fwtable_read32+0xd8/0x130 [i915]
[    4.740575]  i915_hpd_irq_setup+0xa5/0x100 [i915]
[    4.740649]  intel_hpd_init+0x68/0x80 [i915]
[    4.740716]  i915_driver_load+0xe19/0x1380 [i915]
[    4.740784]  i915_pci_probe+0x32/0x90 [i915]
[    4.740799]  pci_device_probe+0x8b/0xf0
[    4.740815]  driver_probe_device+0x2b6/0x450
[    4.740828]  __driver_attach+0xda/0xe0
[    4.740841]  ? driver_probe_device+0x450/0x450
[    4.740853]  bus_for_each_dev+0x5b/0x90
[    4.740865]  driver_attach+0x19/0x20
[    4.740878]  bus_add_driver+0x166/0x260
[    4.740892]  driver_register+0x5b/0xd0
[    4.740906]  ? 0xffffffffa0166000
[    4.740920]  __pci_register_driver+0x47/0x50
[    4.740985]  i915_init+0x5c/0x5e [i915]
[    4.740999]  do_one_initcall+0x3e/0x160
[    4.741015]  ? __vunmap+0x7c/0xc0
[    4.741029]  ? kmem_cache_alloc+0xcf/0x120
[    4.741045]  do_init_module+0x55/0x1c4
[    4.741060]  load_module+0x1f3f/0x25b0
[    4.741073]  ? __symbol_put+0x40/0x40
[    4.741086]  ? kernel_read_file+0x100/0x190
[    4.741100]  SYSC_finit_module+0xbc/0xf0
[    4.741112]  SyS_finit_module+0x9/0x10
[    4.741125]  entry_SYSCALL_64_fastpath+0x17/0x98
[    4.741135] RIP: 0033:0x7f8559a140f9
[    4.741145] RSP: 002b:00007fff7509a3e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[    4.741161] RAX: ffffffffffffffda RBX: 00007f855aba02d1 RCX: 00007f8559a140f9
[    4.741172] RDX: 0000000000000000 RSI: 000055b6db0914f0 RDI: 0000000000000011
[    4.741183] RBP: 0000000000020000 R08: 0000000000000000 R09: 000000000000000e
[    4.741193] R10: 0000000000000011 R11: 0000000000000246 R12: 000055b6db0854d0
[    4.741204] R13: 000055b6db091150 R14: 0000000000000000 R15: 000055b6db035924

v2: Set dev_priv->display_irqs_enabled to true for all platforms other
than vlv/chv that manually control the display power domain.

Fixes: 19625e85c6ec ("drm/i915: Enable polling when we don't have hpd")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97798
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lyude <cpaul@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Hans de Goede <jwrdegoede@fedoraproject.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170215131547.5064-1-chris@chris-wilson.co.uk
Link: http://patchwork.freedesktop.org/patch/msgid/20170313170231.18633-1-chris@chris-wilson.co.uk
(cherry picked from commit 262fd485ac6b476479f41f00bb104f6a1766ae66)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/i915/i915_irq.c      |   10 ++++++++++
 drivers/gpu/drm/i915/intel_hotplug.c |   14 ++++++++------
 2 files changed, 18 insertions(+), 6 deletions(-)

--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -4216,6 +4216,16 @@ void intel_irq_init(struct drm_i915_priv
 	if (!IS_GEN2(dev_priv))
 		dev->vblank_disable_immediate = true;
 
+	/* Most platforms treat the display irq block as an always-on
+	 * power domain. vlv/chv can disable it at runtime and need
+	 * special care to avoid writing any of the display block registers
+	 * outside of the power domain. We defer setting up the display irqs
+	 * in this case to the runtime pm.
+	 */
+	dev_priv->display_irqs_enabled = true;
+	if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
+		dev_priv->display_irqs_enabled = false;
+
 	dev->driver->get_vblank_timestamp = i915_get_vblank_timestamp;
 	dev->driver->get_scanout_position = i915_get_crtc_scanoutpos;
 
--- a/drivers/gpu/drm/i915/intel_hotplug.c
+++ b/drivers/gpu/drm/i915/intel_hotplug.c
@@ -219,7 +219,7 @@ static void intel_hpd_irq_storm_reenable
 			}
 		}
 	}
-	if (dev_priv->display.hpd_irq_setup)
+	if (dev_priv->display_irqs_enabled && dev_priv->display.hpd_irq_setup)
 		dev_priv->display.hpd_irq_setup(dev_priv);
 	spin_unlock_irq(&dev_priv->irq_lock);
 
@@ -425,7 +425,7 @@ void intel_hpd_irq_handler(struct drm_i9
 		}
 	}
 
-	if (storm_detected)
+	if (storm_detected && dev_priv->display_irqs_enabled)
 		dev_priv->display.hpd_irq_setup(dev_priv);
 	spin_unlock(&dev_priv->irq_lock);
 
@@ -471,10 +471,12 @@ void intel_hpd_init(struct drm_i915_priv
 	 * Interrupt setup is already guaranteed to be single-threaded, this is
 	 * just to make the assert_spin_locked checks happy.
 	 */
-	spin_lock_irq(&dev_priv->irq_lock);
-	if (dev_priv->display.hpd_irq_setup)
-		dev_priv->display.hpd_irq_setup(dev_priv);
-	spin_unlock_irq(&dev_priv->irq_lock);
+	if (dev_priv->display_irqs_enabled && dev_priv->display.hpd_irq_setup) {
+		spin_lock_irq(&dev_priv->irq_lock);
+		if (dev_priv->display_irqs_enabled)
+			dev_priv->display.hpd_irq_setup(dev_priv);
+		spin_unlock_irq(&dev_priv->irq_lock);
+	}
 }
 
 static void i915_hpd_poll_init_work(struct work_struct *work)


Patches currently in stable-queue which might be from chris@chris-wilson.co.uk are

queue-4.10/drm-i915-stop-using-rp_down_ei-on-baytrail.patch
queue-4.10/drm-i915-squelch-any-ktime-jiffie-rounding-errors-for-wait-ioctl.patch
queue-4.10/drm-i915-fbdev-stop-repeating-tile-configuration-on-stagnation.patch
queue-4.10/drm-i915-only-enable-hotplug-interrupts-if-the-display-interrupts-are-enabled.patch
queue-4.10/drm-i915-store-a-permanent-error-in-obj-mm.pages.patch
queue-4.10/drm-i915-gen9-increase-pcode-request-timeout-to-50ms.patch
queue-4.10/drm-i915-avoid-tweaking-evaluation-thresholds-on-baytrail-v3.patch
queue-4.10/drm-i915-avoid-rcu_barrier-from-reclaim-paths-shrinker.patch
queue-4.10/drm-i915-drop-support-for-i915_exec_constants_-execbuf-parameters.patch
queue-4.10/drm-i915-fix-forcewake-active-domain-tracking.patch