kernel/linux.git/drivers/gpu/drm/i915/intel_hotplug.c, branch linux-4.20.y

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

2018-11-12T15:07:12+00:00

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 (cherry picked from commit 5a3aeca97af1b6b3498d59a7fd4e8bb95814c108) Signed-off-by: Joonas Lahtinen

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

2018-11-12T15:07:12+00:00

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 (cherry picked from commit fee61deecb1d850bf34f682a6a452e5ee51b7572) Signed-off-by: Joonas Lahtinen

drm/i915: Pass hpd_pin to long_pulse_detect()

2018-07-13T15:22:22+00:00

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

drm/i915: s/int i/enum hpd_pin pin/

2018-07-13T15:22:22+00:00

Use the enum hpd_pin type when talking about HPD pins, and rename the variable from a very nondescript 'i' to 'pin', a name we already use in other parts of the code. Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20180705164357.28512-6-ville.syrjala@linux.intel.com Reviewed-by: Rodrigo Vivi

drm/i915: Nuke dev_priv->irq_port[]

2018-07-13T15:22:22+00:00

Instead of looping over ports and hpd_pins, let's loop over the encoders when doing hotplug processing. And instead of depending on dev_priv->irq_port[] to tell us whether the encoder has the ->hpd_pulse() hook or not, we can just check for that directly. So we can just nuke irq_port[] entirely. Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20180705164357.28512-5-ville.syrjala@linux.intel.com Reviewed-by: Rodrigo Vivi

drm/i915/icl: HPD pin for port F

2018-03-23T21:59:09+00:00

Extend enum hpd_pin to port F so that we can start using this for ICL. v2: Rebase. Cc: Rodrigo Vivi Cc: Paulo Zanoni Reviewed-by: Rodrigo Vivi Signed-off-by: Dhinakaran Pandiyan Signed-off-by: Paulo Zanoni Link: https://patchwork.freedesktop.org/patch/msgid/20180323172419.24911-6-paulo.r.zanoni@intel.com

drm/i915: Reinitialize sink scrambling/TMDS clock ratio on HPD

2018-03-06T22:57:24+00:00

The LG 4k TV I have doesn't deassert HPD when I turn the TV off, but when I turn it back on it will pulse the HPD line. By that time it has forgotten everything we told it about scrambling and the clock ratio. Hence if we want to get a picture out if it again we have to tell it whether we're currently sending scrambled data or not. Implement that via the encoder->hotplug() hook. v2: Force a full modeset to not follow the HDMI 2.0 spec more closely (Shashank) [pushed with whitespace fixes to make sparse happy] Cc: Shashank Sharma Cc: Maarten Lankhorst Signed-off-by: Ville Syrjälä Signed-off-by: Lyude Paul Link: https://patchwork.freedesktop.org/patch/msgid/20180117192149.17760-1-ville.syrjala@linux.intel.com

drm/i915/cnl: Add HPD support for Port F.

2018-01-30T18:24:20+00:00

On CNP boards that are using DDI F, bit 25 (SDE_PORTE_HOTPLUG_SPT) is representing the Digital Port F hotplug line when the Digital Port F hotplug detect input is enabled. v2: Reuse all existent structure instead of adding a new HPD_PORT_F pointing to pin of port E. v3: Use IS_CNL_WITH_PORT_F so we can start upstreaming this right now. If that SKU ever get a proper name we come back and update it. v4: Rebase on top of digital connected port using encoder instead of port. v5: Moved IS_CNL_WITH_PORT_F definition to the PCI IDs patch. Cc: Lucas De Marchi Cc: Manasi Navare Cc: Dhinakaran Pandiyan Cc: Ville Syrjälä Signed-off-by: Rodrigo Vivi Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20180129232223.766-8-rodrigo.vivi@intel.com

drm/i915: Introduce intel_hpd_pin function.

2017-08-11T18:53:47+00:00

The idea is to have an unique place to decide the pin-port per platform. So let's create this function now without any functional change. Just adding together code from hdmi and dp together. v2: Add missing pin for port A. v3: Fix typo on subject. Avoid behaviour change so add WARN_ON and return if port A on HDMI. (by DK). Cc: Dhinakaran Pandiyan Cc: Ville Syrjälä Signed-off-by: Rodrigo Vivi Reviewed-by: Dhinakaran Pandiyan Link: https://patchwork.freedesktop.org/patch/msgid/20170811182650.14327-2-rodrigo.vivi@intel.com

drm/i915: Simplify hpd pin to port

2017-08-11T18:53:31+00:00

We will soon need to make that pin port association per platform, so let's try to simplify it beforehand. Also we are moving the backwards port to pin here as well so let's use a standardized way. One extra possibility here would be to add a MISSING_CASE along with PORT_NONE, but I don't want to change this behaviour for now. Cc: Ville Syrjälä Signed-off-by: Rodrigo Vivi Reviewed-by: Dhinakaran Pandiyan Link: https://patchwork.freedesktop.org/patch/msgid/20170811182650.14327-1-rodrigo.vivi@intel.com