kernel/drivers/gpu/drm/i915/intel_hotplug.c, branch linux-5.1.y

drm/i915: Rename HAS_GMCH

2019-02-05T17:43:23Z

First of all GMCH can be considered a feature by itself since it is a chip present in some platforms that connects the IA processor to memory and other components in PC. Also with the introduction of display block at device info, we got a redundant definition: .display.has_gmch_display = 1, So, let's clean up things a bit and use the standardized way of has_feature on displays side. No functional change and no manual interaction to generate this patch. It is only: sed -si -e 's/has_gmch_display/has_gmch/g' \ -e 's/HAS_GMCH_DISPLAY/HAS_GMCH/g' drivers/gpu/drm/i915/*{c,h} Cc: José Roberto de Souza Cc: Ville Syrjälä Signed-off-by: Rodrigo Vivi Reviewed-by: José Roberto de Souza Link: https://patchwork.freedesktop.org/patch/msgid/20190204222538.15842-1-rodrigo.vivi@intel.com

drm/i915/hotplug: Track temporary rpm wakeref

2019-01-14T16:18:18Z

Keep track of the temporary rpm wakeref inside hotplug detection, so that we can cancel it immediately upon release and so clearly identify leaks. Signed-off-by: Chris Wilson Cc: Jani Nikula Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-12-chris@chris-wilson.co.uk

drm/i915: Markup paired operations on wakerefs

2019-01-14T16:17:53Z

The majority of runtime-pm operations are bounded and scoped within a function; these are easy to verify that the wakeref are handled correctly. We can employ the compiler to help us, and reduce the number of wakerefs tracked when debugging, by passing around cookies provided by the various rpm_get functions to their rpm_put counterpart. This makes the pairing explicit, and given the required wakeref cookie the compiler can verify that we pass an initialised value to the rpm_put (quite handy for double checking error paths). For regular builds, the compiler should be able to eliminate the unused local variables and the program growth should be minimal. Fwiw, it came out as a net improvement as gcc was able to refactor rpm_get and rpm_get_if_in_use together, v2: Just s/rpm_put/rpm_put_unchecked/ everywhere, leaving the manual mark up for smaller more targeted patches. v3: Mention the cookie in Returns Signed-off-by: Chris Wilson Cc: Jani Nikula Cc: Mika Kuoppala Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-2-chris@chris-wilson.co.uk

drm/i915: drop all drmP.h includes

2019-01-09T08:26:36Z

Needs just a few additional includes here and there. Cc: Sam Ravnborg Cc: Daniel Vetter Cc: Laurent Pinchart Acked-by: Daniel Vetter Acked-by: Sam Ravnborg Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20190108082709.3748-1-jani.nikula@intel.com

drm/i915: Fix hpd handling for pins with two encoders

2018-11-09T15:40:57Z

In my haste to remove irq_port[] I accidentally changed the way we deal with hpd pins that are shared by multiple encoders (DP and HDMI for pre-DDI platforms). Previously we would only handle such pins via ->hpd_pulse(), but now we queue up the hotplug work for the HDMI encoder directly. Worse yet, we now count each hpd twice and this increment the hpd storm count twice as fast. This can lead to spurious storms being detected. Go back to the old way of doing things, ie. delegate to ->hpd_pulse() for any pin which has an encoder with that hook implemented. I don't really like the idea of adding irq_port[] back so let's loop through the encoders first to check if we have an encoder with ->hpd_pulse() for the pin, and then go through all the pins and decided on the correct course of action based on the earlier findings. I have occasionally toyed with the idea of unifying the pre-DDI HDMI and DP encoders into a single encoder as well. Besides the hotplug processing it would have the other benefit of preventing userspace from trying to enable both encoders at the same time. That is simply illegal as they share the same clock/data pins. We have some testcases that will attempt that and thus fail on many older machines. But for now let's stick to fixing just the hotplug code. Cc: stable@vger.kernel.org # 4.19+ Cc: Lyude Paul Cc: Rodrigo Vivi Fixes: b6ca3eee18ba ("drm/i915: Nuke dev_priv->irq_port[]") Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20181108200424.28371-1-ville.syrjala@linux.intel.com Reviewed-by: Lyude Paul

drm/i915: Add short HPD IRQ storm detection for non-MST systems

2018-11-07T20:12:30Z

Unfortunately, it seems that the HPD IRQ storm problem from the early days of Intel GPUs was never entirely solved, only mostly. Within the last couple of days, I got a bug report from one of our customers who had been having issues with their machine suddenly booting up very slowly after having updated. The amount of time it took to boot went from around 30 seconds, to over 6 minutes consistently. After some investigation, I discovered that i915 was reporting massive amounts of short HPD IRQ spam on this system from the DisplayPort port, despite there not being anything actually connected. The symptoms would start with one "long" HPD IRQ being detected at boot: [ 1.891398] [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x00440000, dig 0x00440000, pins 0x000000a0 [ 1.891436] [drm:intel_hpd_irq_handler [i915]] digital hpd port B - long [ 1.891472] [drm:intel_hpd_irq_handler [i915]] Received HPD interrupt on PIN 5 - cnt: 0 [ 1.891508] [drm:intel_hpd_irq_handler [i915]] digital hpd port D - long [ 1.891544] [drm:intel_hpd_irq_handler [i915]] Received HPD interrupt on PIN 7 - cnt: 0 [ 1.891592] [drm:intel_dp_hpd_pulse [i915]] got hpd irq on port B - long [ 1.891628] [drm:intel_dp_hpd_pulse [i915]] got hpd irq on port D - long … followed by constant short IRQs afterwards: [ 1.895091] [drm:intel_encoder_hotplug [i915]] [CONNECTOR:66:DP-1] status updated from unknown to disconnected [ 1.895129] [drm:i915_hotplug_work_func [i915]] Connector DP-3 (pin 7) received hotplug event. [ 1.895165] [drm:intel_dp_detect [i915]] [CONNECTOR:72:DP-3] [ 1.895275] [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x00200000, dig 0x00200000, pins 0x00000080 [ 1.895312] [drm:intel_hpd_irq_handler [i915]] digital hpd port D - short [ 1.895762] [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x00200000, dig 0x00200000, pins 0x00000080 [ 1.895799] [drm:intel_hpd_irq_handler [i915]] digital hpd port D - short [ 1.896239] [drm:intel_dp_aux_xfer [i915]] dp_aux_ch timeout status 0x71450085 [ 1.896293] [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x00200000, dig 0x00200000, pins 0x00000080 [ 1.896330] [drm:intel_hpd_irq_handler [i915]] digital hpd port D - short [ 1.896781] [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x00200000, dig 0x00200000, pins 0x00000080 [ 1.896817] [drm:intel_hpd_irq_handler [i915]] digital hpd port D - short [ 1.897275] [drm:intel_get_hpd_pins [i915]] hotplug event received, stat 0x00200000, dig 0x00200000, pins 0x00000080 The customer's system in question has a GM45 GPU, which is apparently well known for hotplugging storms. So, workaround this impressively broken hardware by changing the default HPD storm threshold from 5 to 50. Then, make long IRQs count for 10, and short IRQs count for 1. This makes it so that 5 long IRQs will trigger an HPD storm, and on systems with short HPD storm detection 50 short IRQs will trigger an HPD storm. 50 short IRQs amounts to 100ms of constant pulsing, which seems like a good middleground between being too sensitive and not being sensitive enough (which would cause visible stutters in userspace every time a storm occurs). And just to be extra safe: we don't enable this by default on systems with MST support. There's too high of a chance of MST support triggering storm detection, and systems that are new enough to support MST are a lot less likely to have issues with IRQ storms anyway. As a note: this patch was tested using a ThinkPad T450s and a Chamelium to simulate the short IRQ storms. Changes since v1: - Don't use two separate thresholds, just make long IRQs count for 10 each and short IRQs count for 1. This simplifies the code a bit - Ville Syrjälä Changes since v2: - Document @long_hpd in intel_hpd_irq_storm_detect, no functional changes Changes since v4: - Remove !! in long_hpd assignment - Ville Syrjälä - queue_hp = true - Ville Syrjälä Signed-off-by: Lyude Paul Cc: Ville Syrjälä Cc: Rodrigo Vivi Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20181106213017.14563-6-lyude@redhat.com

drm/i915: Clarify flow for disabling IRQs on storms

2018-11-07T20:11:44Z

This is rather confusing to look at as-is: dev_priv->display.hpd_irq_setup(dev_priv); in intel_hpd_irq_handler() handles disabling the actual HPD IRQ, while intel_hpd_irq_storm_disable() handles moving the HPD pin state over from MARK_DISABLED to DISABLED along with enabling polling for it. Changes since v3: - Rename i915_hpd_irq_storm_disable() to i915_hpd_irq_storm_switch_to_polling() - Rodrigo Vivi Signed-off-by: Lyude Paul Reviewed-by: Ville Syrjälä Cc: Rodrigo Vivi Link: https://patchwork.freedesktop.org/patch/msgid/20181106213017.14563-5-lyude@redhat.com

drm/i915: Fix threshold check in intel_hpd_irq_storm_detect()

2018-11-07T20:11:29Z

Currently in intel_hpd_irq_storm_detect() when we detect that the last recorded hotplug wasn't within the period defined by HPD_STORM_DETECT_DELAY, we make the mistake of resetting the HPD count to 0 without incrementing it. This results in us only enabling storm detection when we go +2 above the threshold, e.g. an HPD threshold of 5 would not trigger a storm until we reach a total of 7 hotplugs. So: rework the code a bit so we reset the HPD count when HPD_STORM_DETECT_DELAY has passed, then increment the count afterwards. Also, clean things up a bit to make it easier to undertand. Signed-off-by: Lyude Paul Reviewed-by: Ville Syrjälä Cc: Rodrigo Vivi Link: https://patchwork.freedesktop.org/patch/msgid/20181106213017.14563-4-lyude@redhat.com

drm/i915: Fix NULL deref when re-enabling HPD IRQs on systems with MST

2018-11-07T20:10:58Z

Turns out that if you trigger an HPD storm on a system that has an MST topology connected to it, you'll end up causing the kernel to eventually hit a NULL deref: [ 332.339041] BUG: unable to handle kernel NULL pointer dereference at 00000000000000ec [ 332.340906] PGD 0 P4D 0 [ 332.342750] Oops: 0000 [#1] SMP PTI [ 332.344579] CPU: 2 PID: 25 Comm: kworker/2:0 Kdump: loaded Tainted: G O 4.18.0-rc3short-hpd-storm+ #2 [ 332.346453] Hardware name: LENOVO 20BWS1KY00/20BWS1KY00, BIOS JBET71WW (1.35 ) 09/14/2018 [ 332.348361] Workqueue: events intel_hpd_irq_storm_reenable_work [i915] [ 332.350301] RIP: 0010:intel_hpd_irq_storm_reenable_work.cold.3+0x2f/0x86 [i915] [ 332.352213] Code: 00 00 ba e8 00 00 00 48 c7 c6 c0 aa 5f a0 48 c7 c7 d0 73 62 a0 4c 89 c1 4c 89 04 24 e8 7f f5 af e0 4c 8b 04 24 44 89 f8 29 e8 <41> 39 80 ec 00 00 00 0f 85 43 13 fc ff 41 0f b6 86 b8 04 00 00 41 [ 332.354286] RSP: 0018:ffffc90000147e48 EFLAGS: 00010006 [ 332.356344] RAX: 0000000000000005 RBX: ffff8802c226c9d4 RCX: 0000000000000006 [ 332.358404] RDX: 0000000000000000 RSI: 0000000000000082 RDI: ffff88032dc95570 [ 332.360466] RBP: 0000000000000005 R08: 0000000000000000 R09: ffff88031b3dc840 [ 332.362528] R10: 0000000000000000 R11: 000000031a069602 R12: ffff8802c226ca20 [ 332.364575] R13: ffff8802c2268000 R14: ffff880310661000 R15: 000000000000000a [ 332.366615] FS: 0000000000000000(0000) GS:ffff88032dc80000(0000) knlGS:0000000000000000 [ 332.368658] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 332.370690] CR2: 00000000000000ec CR3: 000000000200a003 CR4: 00000000003606e0 [ 332.372724] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 332.374773] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 332.376798] Call Trace: [ 332.378809] process_one_work+0x1a1/0x350 [ 332.380806] worker_thread+0x30/0x380 [ 332.382777] ? wq_update_unbound_numa+0x10/0x10 [ 332.384772] kthread+0x112/0x130 [ 332.386740] ? kthread_create_worker_on_cpu+0x70/0x70 [ 332.388706] ret_from_fork+0x35/0x40 [ 332.390651] Modules linked in: i915(O) vfat fat joydev btusb btrtl btbcm btintel bluetooth ecdh_generic iTCO_wdt wmi_bmof i2c_algo_bit drm_kms_helper intel_rapl syscopyarea sysfillrect x86_pkg_temp_thermal sysimgblt coretemp fb_sys_fops crc32_pclmul drm psmouse pcspkr mei_me mei i2c_i801 lpc_ich mfd_core i2c_core tpm_tis tpm_tis_core thinkpad_acpi wmi tpm rfkill video crc32c_intel serio_raw ehci_pci xhci_pci ehci_hcd xhci_hcd [last unloaded: i915] [ 332.394963] CR2: 00000000000000ec This appears to be due to the fact that with an MST topology, not all intel_connector structs will have ->encoder set. So, fix this by skipping connectors without encoders in intel_hpd_irq_storm_reenable_work(). For those wondering, this bug was found on accident while simulating HPD storms using a Chamelium connected to a ThinkPad T450s (Broadwell). Changes since v1: - Check intel_connector->mst_port instead of intel_connector->encoder Signed-off-by: Lyude Paul Reviewed-by: Ville Syrjälä Cc: stable@vger.kernel.org Cc: Rodrigo Vivi Link: https://patchwork.freedesktop.org/patch/msgid/20181106213017.14563-3-lyude@redhat.com

drm/i915: Pass hpd_pin to long_pulse_detect()

2018-07-13T15:22:22Z

We're doing a pointless translation from hpd_pin to port simply for passing the thing to long_pulse_detect(). Let's pass the hpd_pin directly instead. This removes the assumption that the hpd_pin and port always match. The only other place where we make that assumption anymore is intel_hpd_pin_default() and that's fine as it's what determines the relationship between the two. If we ever get hardware where the hpd pins are wired in more interesting ways it should be trivial to handle from now on. This should also fix the IS_CNL_WITH_PORT_F() case as that mapped pin E back to port F and passed that to spt_port_hotplug2_long_detect() which would always return false for port F. Now that we pass in pin E directly it'll actually do the right thing. Cc: Rodrigo Vivi Fixes: cf53902f48c3 ("drm/i915/cnl: Add HPD support for Port F.") Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20180705164357.28512-7-ville.syrjala@linux.intel.com Reviewed-by: Rodrigo Vivi