linux/drivers/gpu/drm/i915
Rodrigo Vivi bc5f2ab11c drm/i915/skl: Don't call intel_prepare_ddi when encoder list isn't yet initialized.
In case something goes wrong with power well initialization we were calling
intel_prepare_ddi during boot while encoder list isnt't initilized.

[    9.618747] i915 0000:00:02.0: Invalid ROM contents
[    9.631446] [drm] failed to find VBIOS tables
[    9.720036] BUG: unable to handle kernel NULL pointer dereference at 00000000
00000058
[    9.721986] IP: [<ffffffffa014eb72>] ddi_get_encoder_port+0x82/0x190 [i915]
[    9.723736] PGD 0
[    9.724286] Oops: 0000 [#1] PREEMPT SMP
[    9.725386] Modules linked in: intel_powerclamp snd_hda_intel(+) coretemp crc
32c_intel snd_hda_codec snd_hda_core serio_raw snd_pcm snd_timer i915(+) parport
_pc parport pinctrl_sunrisepoint pinctrl_intel nfsd nfs_acl
[    9.730635] CPU: 0 PID: 497 Comm: systemd-udevd Not tainted 4.3.0-rc2-eywa-10
967-g72de2cfd-dirty #2
[    9.732785] Hardware name: Intel Corporation Cannonlake Client platform/Skyla
ke DT DDR4 RVP8, BIOS CNLSE2R1.R00.X021.B00.1508040310 08/04/2015
[    9.735785] task: ffff88008a704700 ti: ffff88016a1ac000 task.ti: ffff88016a1a
c000
[    9.737584] RIP: 0010:[<ffffffffa014eb72>]  [<ffffffffa014eb72>] ddi_get_enco
der_port+0x82/0x190 [i915]
[    9.739934] RSP: 0000:ffff88016a1af710  EFLAGS: 00010296
[    9.741184] RAX: 000000000000004e RBX: ffff88008a9edc98 RCX: 0000000000000001
[    9.742934] RDX: 000000000000004e RSI: ffffffff81fc1e82 RDI: 00000000ffffffff
[    9.744634] RBP: ffff88016a1af730 R08: 0000000000000000 R09: 0000000000000578
[    9.746333] R10: 0000000000001065 R11: 0000000000000578 R12: fffffffffffffff8
[    9.748033] R13: ffff88016a1af7a8 R14: ffff88016a1af794 R15: 0000000000000000
[    9.749733] FS:  00007eff2e1e07c0(0000) GS:ffff88016fc00000(0000) knlGS:00000
00000000000
[    9.751683] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    9.753083] CR2: 0000000000000058 CR3: 000000016922b000 CR4: 00000000003406f0
[    9.754782] Stack:
[    9.755332]  ffff88008a9edc98 ffff88008a9ed800 ffffffffa01d07b0 00000000fffb9
09e
[    9.757232]  ffff88016a1af7d8 ffffffffa0154ea7 0000000000000246 ffff88016a370
080
[    9.759182]  ffff88016a370080 ffff88008a9ed800 0000000000000246 ffff88008a9ed
c98
[    9.761132] Call Trace:
[    9.761782]  [<ffffffffa0154ea7>] intel_prepare_ddi+0x67/0x860 [i915]
[    9.763332]  [<ffffffff81a56996>] ? _raw_spin_unlock_irqrestore+0x26/0x40
[    9.765031]  [<ffffffffa00fad01>] ? gen9_read32+0x141/0x360 [i915]
[    9.766531]  [<ffffffffa00b43e1>] skl_set_power_well+0x431/0xa80 [i915]
[    9.768181]  [<ffffffffa00b4a63>] skl_power_well_enable+0x13/0x20 [i915]
[    9.769781]  [<ffffffffa00b2188>] intel_power_well_enable+0x28/0x50 [i915]
[    9.771481]  [<ffffffffa00b4d52>] intel_display_power_get+0x92/0xc0 [i915]
[    9.773180]  [<ffffffffa00b4fcb>] intel_display_set_init_power+0x3b/0x40 [i91
5]
[    9.774980]  [<ffffffffa00b5170>] intel_power_domains_init_hw+0x120/0x520 [i9
15]
[    9.776780]  [<ffffffffa0194c61>] i915_driver_load+0xb21/0xf40 [i915]

So let's protect this case.

My first attempt was to remove the intel_prepare_ddi, but Daniel had pointed out
this is really needed to restore those registers values. And Imre pointed out
that this case was without the flag protection and this was actually where things
were going bad. So I've just checked and this indeed solves my issue.

The regressing intel_prepare_ddi call was added in

commit 1d2b9526a7
Author: Damien Lespiau <damien.lespiau@intel.com>
Date:   Fri Mar 6 18:50:53 2015 +0000

    drm/i915/skl: Restore the DDI translation tables when enabling PW1

Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
[Jani: regression reference]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2015-09-28 11:05:13 +03:00
..
dvo_ch7xxx.c
dvo_ch7017.c
dvo_ivch.c Fix resume from suspend on IBM X30 2015-06-15 12:21:01 +02:00
dvo_ns2501.c drm/i915: Enable dithering on NatSemi DVO2501 for Fujitsu S6010 2015-04-23 21:31:58 +02:00
dvo_sil164.c
dvo_tfp410.c
dvo.h
i915_cmd_parser.c drm/i915: Fix command parser table validator 2015-07-29 10:31:04 +02:00
i915_debugfs.c drm/i915/skl: Adding DDI_E power well domain 2015-08-31 18:40:48 +03:00
i915_dma.c drm/i915: Fake AGP is dead 2015-07-28 13:30:00 +02:00
i915_drv.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-09-04 15:49:32 -07:00
i915_drv.h Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2015-09-11 09:35:56 -07:00
i915_gem_batch_pool.c drm/i915: Split batch pool into size buckets 2015-04-10 08:56:05 +02:00
i915_gem_batch_pool.h drm/i915: Split batch pool into size buckets 2015-04-10 08:56:05 +02:00
i915_gem_context.c drm/i915: Remove the failed context from the fpriv->context_idr 2015-08-14 17:50:41 +02:00
i915_gem_debug.c drm/i915: Implement inter-engine read-read optimisations 2015-05-21 15:11:42 +02:00
i915_gem_dmabuf.c drm/i915: remove unused has_dma_mapping flag 2015-07-13 22:42:41 +02:00
i915_gem_evict.c
i915_gem_execbuffer.c drm/i915: Always mark the object as dirty when used by the GPU 2015-09-02 16:21:53 +03:00
i915_gem_fence.c drm/i915: kerneldoc for tiling IOCTL and swizzle functions 2015-07-27 10:26:30 +02:00
i915_gem_gtt.c Linux 4.2-rc7 2015-08-17 14:13:53 +10:00
i915_gem_gtt.h drm/i915/gtt: Move scratch_pd and scratch_pt into vm struct 2015-06-26 11:06:30 +02:00
i915_gem_render_state.c drm/i915: Add provision to extend Golden context batch 2015-07-21 09:30:57 +02:00
i915_gem_render_state.h drm/i915: Add provision to extend Golden context batch 2015-07-21 09:30:57 +02:00
i915_gem_shrinker.c drm/i915: Simplify object is-pinned checking for shrinker 2015-04-10 10:58:34 +02:00
i915_gem_stolen.c drm/i915: Fix build warning on 32-bit 2015-08-26 10:15:36 +03:00
i915_gem_tiling.c Merge tag 'drm-intel-fixes-2015-08-14' into drm-intel-next-fixes 2015-08-14 18:11:30 +02:00
i915_gem_userptr.c drm/i915: avoid leaking DMA mappings 2015-07-13 22:42:40 +02:00
i915_gem.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-09-04 15:49:32 -07:00
i915_gpu_error.c drm/i915: Report IOMMU enabled status for GPU hangs 2015-08-14 17:50:41 +02:00
i915_guc_reg.h drm/i915: Add GuC-related header files 2015-07-21 08:38:00 +02:00
i915_ioc32.c Merge tag 'drm-intel-fixes-2015-07-15' into drm-intel-next-queued 2015-07-15 16:36:50 +02:00
i915_irq.c drm/i915: workaround bad DSL readout v3 2015-09-23 10:13:50 +03:00
i915_params.c drm/i915: Add GuC-related module parameters 2015-07-21 08:37:35 +02:00
i915_reg.h drm/i915/skl: enable DDI-E hotplug 2015-08-26 10:24:25 +03:00
i915_suspend.c drm/i915: use dev_priv for the FBC functions 2015-07-08 11:39:45 +02:00
i915_sysfs.c drm/i915/vlv: fix RC6 residency time calculation 2015-06-15 11:56:37 +02:00
i915_trace_points.c
i915_trace.h Merge tag 'drm-intel-fixes-2015-07-15' into drm-intel-next-queued 2015-07-15 16:36:50 +02:00
i915_vgpu.c
i915_vgpu.h
intel_acpi.c
intel_atomic_plane.c drm/i915: Remove transitional references from intel_plane_atomic_check. 2015-06-22 14:28:29 +02:00
intel_atomic.c drm/i915: Commit planes on each crtc separately. 2015-08-13 12:09:18 +03:00
intel_audio.c drm/i915: fix kernel-doc warnings in intel_audio.c 2015-09-21 10:03:53 +03:00
intel_bios.c drm/i915/bios: handle MIPI Sequence Block v3+ gracefully 2015-09-23 16:59:37 +03:00
intel_bios.h drm/i915: eDP can be present on DDI-E 2015-08-31 18:36:38 +03:00
intel_crt.c drm/i915: Get rid of dpms handling. 2015-08-14 17:50:33 +02:00
intel_csr.c drm/i915: Fix CSR MMIO address check 2015-09-10 10:32:48 +03:00
intel_ddi.c drm/i915: Don't use link_bw for PLL setup 2015-09-01 12:31:44 +03:00
intel_display.c drm/i915: Add primary plane to mask if it's visible 2015-09-23 13:18:26 +03:00
intel_dp_mst.c drm/i915: Fix broken mst get_hw_state. 2015-09-08 16:16:50 +03:00
intel_dp.c i915: Set ddi_pll_sel in DP MST path 2015-09-01 12:42:27 +03:00
intel_drv.h i915: Set ddi_pll_sel in DP MST path 2015-09-01 12:42:27 +03:00
intel_dsi_panel_vbt.c drm/i915: s/dpio_lock/sb_lock/ 2015-05-28 11:13:51 +02:00
intel_dsi_pll.c drm/i915: Changes required to enable DSI Video Mode on CHT 2015-07-03 07:39:02 +02:00
intel_dsi.c drm/i915: Allow DSI dual link to be configured on any pipe 2015-09-10 16:23:42 +03:00
intel_dsi.h drm/i915: Use the CRC gpio for panel enable/disable 2015-07-21 09:22:43 +02:00
intel_dvo.c drm/i915: Get rid of dpms handling. 2015-08-14 17:50:33 +02:00
intel_fbc.c drm/i915: fix FBC frontbuffer tracking flushing code 2015-08-05 09:59:44 +02:00
intel_fbdev.c drm/i915: Use new drm_fb_helper functions 2015-08-06 14:13:05 +02:00
intel_fifo_underrun.c
intel_frontbuffer.c drm/i915: fix FBC frontbuffer tracking flushing code 2015-08-05 09:59:44 +02:00
intel_guc_fwif.h drm/i915: Add GuC-related header files 2015-07-21 08:38:00 +02:00
intel_hdmi.c drm/i915: Enable HDMI on DDI-E 2015-08-31 18:27:02 +03:00
intel_hotplug.c drm/i915/skl: enable DDI-E hotplug 2015-08-26 10:24:25 +03:00
intel_i2c.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-06-26 13:18:51 -07:00
intel_lrc.c Linux 4.2-rc8 2015-08-24 16:36:42 +10:00
intel_lrc.h drm/i915: Added Programming of the MOCS 2015-07-14 17:13:14 +02:00
intel_lvds.c drm/i915: Get rid of dpms handling. 2015-08-14 17:50:33 +02:00
intel_mocs.c drm/i915: Added Programming of the MOCS 2015-07-14 17:13:14 +02:00
intel_mocs.h drm/i915: Added Programming of the MOCS 2015-07-14 17:13:14 +02:00
intel_modes.c
intel_opregion.c Merge tag 'drm-intel-fixes-2015-07-15' into drm-intel-next-queued 2015-07-15 16:36:50 +02:00
intel_overlay.c drm/i915: Update intel_ring_begin() to take a request structure 2015-06-23 14:02:29 +02:00
intel_panel.c drm/i915: Backlight control using CRC PMIC based PWM driver 2015-07-21 09:22:48 +02:00
intel_pm.c drm/i915: Don't try to use DDR DVFS on CHV when disabled in the BIOS 2015-09-10 15:40:02 +03:00
intel_psr.c drm/i915: VLV/CHV PSR: Increase wait delay time before active PSR. 2015-08-05 10:07:44 +02:00
intel_renderstate_gen6.c
intel_renderstate_gen7.c
intel_renderstate_gen8.c
intel_renderstate_gen9.c
intel_renderstate.h
intel_ringbuffer.c drm/i915: Contain the WA_REG macro 2015-08-14 17:50:42 +02:00
intel_ringbuffer.h Merge tag 'drm-intel-fixes-2015-07-15' into drm-intel-next-queued 2015-07-15 16:36:50 +02:00
intel_runtime_pm.c drm/i915/skl: Don't call intel_prepare_ddi when encoder list isn't yet initialized. 2015-09-28 11:05:13 +03:00
intel_sdvo_regs.h
intel_sdvo.c drm/i915: Get rid of dpms handling. 2015-08-14 17:50:33 +02:00
intel_sideband.c drm/i915: s/dpio_lock/sb_lock/ 2015-05-28 11:13:51 +02:00
intel_sprite.c drm/i915: always disable irqs in intel_pipe_update_start 2015-07-15 15:06:02 +02:00
intel_tv.c drm/i915: Get rid of dpms handling. 2015-08-14 17:50:33 +02:00
intel_uncore.c Linux 4.2-rc7 2015-08-17 14:13:53 +10:00
Kconfig drm/i915: Use CONFIG_DRM_FBDEV_EMULATION 2015-08-11 14:00:29 +02:00
Makefile Merge tag 'drm-intel-next-fixes-2015-08-16' of git://anongit.freedesktop.org/drm-intel into drm-next 2015-08-17 14:14:44 +10:00