[PATCH] drm/i915: Do not call intel_crtc_disable if the crtc is already disabled.

Maarten Lankhorst
2015-07-14T11:00:43Z

When resuming with dpms off, the following warn can happen:

[ 118.334082] ------------[ cut here ]------------
[ 118.334105] WARNING: CPU: 2 PID: 2274 at drivers/gpu/drm/i915/intel_display.c:6319 __intel_set_mode+0xae5/0xb90 [i915]()
[ 118.334106] WARN_ON(!crtc->state->enable)
[ 118.334137] Modules linked in: i915
[ 118.334139] CPU: 2 PID: 2274 Comm: kworker/u16:117 Not tainted 4.2.0-rc2-fixes+ #4148
[ 118.334140] Hardware name: LENOVO 2349AV8/2349AV8, BIOS G1ETA5WW (2.65 ) 04/15/2014
[ 118.334144] Workqueue: events_unbound async_run_entry_fn
[ 118.334147] ffffffffc017eef0 ffff8800ada93998 ffffffff817aa62a 0000000080000001
[ 118.334149] ffff8800ada939e8 ffff8800ada939d8 ffffffff810807e1 ffff8800ada939c8
[ 118.334151] ffff8800cea3b3d8 0000000000000000 ffff8800ad86b008 ffff880117705668
[ 118.334151] Call Trace:
[ 118.334155] [<ffffffff817aa62a>] dump_stack+0x4f/0x7b
[ 118.334157] [<ffffffff810807e1>] warn_slowpath_common+0x81/0xc0
[ 118.334158] [<ffffffff81080861>] warn_slowpath_fmt+0x41/0x50
[ 118.334173] [<ffffffffc0120375>] __intel_set_mode+0xae5/0xb90 [i915]
[ 118.334188] [<ffffffffc0121312>] ? intel_modeset_compute_config+0x52/0xb40 [i915]
[ 118.334191] [<ffffffff8144de53>] ? drm_atomic_set_fb_for_plane+0x63/0x80
[ 118.334205] [<ffffffffc01269d9>] intel_set_mode+0x29/0x60 [i915]
[ 118.334219] [<ffffffffc012730a>] intel_crtc_restore_mode+0x13a/0x1f0 [i915]
[ 118.334232] [<ffffffffc0101160>] ? gen6_write16+0x250/0x250 [i915]
[ 118.334246] [<ffffffffc01283ec>] intel_modeset_setup_hw_state+0x89c/0xcd0 [i915]
[ 118.334248] [<ffffffff8137d260>] ? pci_pm_thaw+0x90/0x90
[ 118.334255] [<ffffffffc00ac11b>] i915_drm_resume+0xcb/0x160 [i915]
[ 118.334262] [<ffffffffc00ac1d2>] i915_pm_resume+0x22/0x30 [i915]
[ 118.334263] [<ffffffff8137d2c3>] pci_pm_resume+0x63/0xa0
[ 118.334266] [<ffffffff81467550>] dpm_run_callback+0x70/0x420
[ 118.334267] [<ffffffff81467cbd>] device_resume+0x9d/0x1c0
[ 118.334269] [<ffffffff814673d0>] ? initcall_debug_start+0x60/0x60
[ 118.334270] [<ffffffff81467dfc>] async_resume+0x1c/0x50
[ 118.334271] [<ffffffff810a6a94>] async_run_entry_fn+0x34/0xd0
[ 118.334273] [<ffffffff8109d4ad>] process_one_work+0x1dd/0x7e0
[ 118.334275] [<ffffffff8109d41a>] ? process_one_work+0x14a/0x7e0
[ 118.334276] [<ffffffff8109daf9>] worker_thread+0x49/0x450
[ 118.334278] [<ffffffff8109dab0>] ? process_one_work+0x7e0/0x7e0
[ 118.334280] [<ffffffff810a3cb9>] kthread+0xf9/0x110
[ 118.334282] [<ffffffff810a3bc0>] ? insert_kthread_work+0x90/0x90
[ 118.334284] [<ffffffff817b414f>] ret_from_fork+0x3f/0x70
[ 118.334286] [<ffffffff810a3bc0>] ? insert_kthread_work+0x90/0x90
[ 118.334287] ---[ end trace 01f2cf6371b82d7a ]---

This warn is harmless, and can be fixed by not calling intel_crtc_disable when
the crtc is already disabled.

Reported-and-Tested-by: Jörg Otte <jrg.otte@gmail.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 85ac6d85dc39..30e0f54ba19d 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6315,9 +6315,6 @@ static void intel_crtc_disable(struct drm_crtc *crtc)
struct drm_connector *connector;
struct drm_i915_private *dev_priv = dev->dev_private;

- /* crtc should still be enabled when we disable it. */
- WARN_ON(!crtc->state->enable);
-
intel_crtc_disable_planes(crtc);
dev_priv->display.crtc_disable(crtc);
dev_priv->display.off(crtc);
@@ -12591,7 +12588,8 @@ static int __intel_set_mode(struct drm_crtc *modeset_crtc,
continue;

if (!crtc_state->enable) {
- intel_crtc_disable(crtc);
+ if (crtc->state->enable)
+ intel_crtc_disable(crtc);
} else if (crtc->state->enable) {
intel_crtc_disable_planes(crtc);
dev_priv->display.crtc_disable(crtc);