linux/drivers
Ville Syrjälä 237aab5496 drm/i915/vrr: Configure VRR timings after enabling TRANS_DDI_FUNC_CTL
Apparently ICL may hang with an MCE if we write TRANS_VRR_VMAX/FLIPLINE
before enabling TRANS_DDI_FUNC_CTL.

Personally I was only able to reproduce a hang (on an Dell XPS 7390
2-in-1) with an external display connected via a dock using a dodgy
type-C cable that made the link training fail. After the failed
link training the machine would hang. TGL seemed immune to the
problem for whatever reason.

BSpec does tell us to configure VRR after enabling TRANS_DDI_FUNC_CTL
as well. The DMC firmware also does the VRR restore in two stages:
- first stage seems to be unconditional and includes TRANS_VRR_CTL
  and a few other VRR registers, among other things
- second stage is conditional on the DDI being enabled,
  and includes TRANS_DDI_FUNC_CTL and TRANS_VRR_VMAX/VMIN/FLIPLINE,
  among other things

So let's reorder the steps to match to avoid the hang, and
toss in an extra WARN to make sure we don't screw this up later.

BSpec: 22243
Cc: stable@vger.kernel.org
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Reported-by: Benjamin Tissoires <bentiss@kernel.org>
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15777
Tested-by: Benjamin Tissoires <bentiss@kernel.org>
Fixes: dda7dcd9da ("drm/i915/vrr: Use fixed timings for platforms that support VRR")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/20260303095414.4331-1-ville.syrjala@linux.intel.com
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
(cherry picked from commit 93f3a267c3)
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
2026-03-10 08:11:29 +00:00
..
accel accel: ethosu: Handle possible underflow in IFM size calculations 2026-03-05 15:21:17 -06:00
accessibility Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
acpi Merge branch 'acpica' 2026-03-05 18:46:43 +01:00
amba Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
android Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
ata ata: libata-eh: Fix detection of deferred qc timeouts 2026-03-06 09:58:47 +01:00
atm Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
auxdisplay Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
base Revert "driver core: enforce device_lock for driver_match_device()" 2026-03-03 13:12:42 +01:00
bcma Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
block block-7.0-20260227 2026-02-27 10:42:02 -08:00
bluetooth Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
bus Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
cache
cdrom Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cdx Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
char Bug fixes for the IPMI driver 2026-02-26 14:34:21 -08:00
clk clk: scu/imx8qxp: do not register driver in probe() 2026-02-24 12:54:17 +01:00
clocksource Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
comedi Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
connector Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
counter Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
cpufreq cpufreq: intel_pstate: Fix crash during turbo disable 2026-02-25 14:39:19 +01:00
cpuidle Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
crypto crypto: atmel-sha204a - Fix OOM ->tfm_count leak 2026-02-28 12:53:25 +09:00
cxl cxl/region: Test CXL_DECODER_F_NORMALIZED_ADDRESSING as a bitmask 2026-02-24 08:33:30 -07:00
dax Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
dca treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
devfreq Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
dibs Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
dio Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
dma Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
dma-buf Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
dpll Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
edac Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
eisa Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
extcon Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
firewire firewire: ohci: initialize page array to use alloc_pages_bulk() correctly 2026-02-28 10:09:24 -08:00
firmware x86/efi: defer freeing of boot services memory 2026-02-25 12:02:48 +01:00
fpga Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
fsi Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
fwctl Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
gnss Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
gpib Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
gpio gpiolib: normalize the return value of gc->get() on behalf of buggy drivers 2026-02-23 11:49:23 +01:00
gpu drm/i915/vrr: Configure VRR timings after enabling TRANS_DDI_FUNC_CTL 2026-03-10 08:11:29 +00:00
greybus Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
hid hid-for-linus-2026030601 2026-03-06 10:00:58 -08:00
hsi Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
hte Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
hv Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
hwmon hwmon: (pmbus/q54sj108a2) fix stack overflow in debugfs read 2026-03-04 16:48:06 -08:00
hwspinlock soc: driver updates for 7.0 2026-02-10 20:45:30 -08:00
hwtracing Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
i2c i2c: i801: Revert "i2c: i801: replace acpi_lock with I2C bus lock" 2026-03-04 12:44:14 +01:00
i3c Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
idle
iio Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
infiniband RDMA/uverbs: Import DMA-BUF module in uverbs_std_types_dmabuf file 2026-02-26 04:58:24 -05:00
input Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
interconnect Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
iommu Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
ipack Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
irqchip Arm: 2026-03-01 15:34:47 -08:00
isdn Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
leds Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
macintosh Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
mailbox treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
mcb Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
md Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
media [GIT PULL for v7.0-rc3] media fixes 2026-03-04 08:12:06 -08:00
memory Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
memstick Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
message Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
mfd Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
misc Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
mmc mmc: sdhci-brcmstb: use correct register offset for V1 pin_sel restore 2026-02-23 12:05:20 +01:00
most Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
mtd Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
mux Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
net xen: branch for v7.0-rc3 2026-03-07 07:44:32 -08:00
nfc Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
ntb kmalloc_obj treewide refactoring for v7.0-rc1 2026-02-21 11:02:58 -08:00
nubus Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
nvdimm Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
nvme block-7.0-20260305 2026-03-06 08:36:18 -08:00
nvmem Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
of Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
opp Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
parisc Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
parport Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
pci xen: branch for v7.0-rc3 2026-03-07 07:44:32 -08:00
pcmcia Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
peci Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
perf Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
phy Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
pinctrl pinctrl: cy8c95x0: Don't miss reading the last bank registers 2026-02-26 23:41:04 +01:00
platform platform/x86: dell-wmi-sysman: Don't hex dump plaintext password data 2026-03-03 14:45:17 +02:00
pmdomain pmdomain providers: 2026-03-06 09:16:39 -08:00
pnp Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
power Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
powercap Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
pps Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ps3 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ptp Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
pwm Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rapidio Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ras Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
regulator regulator: pf9453: Respect IRQ trigger settings from firmware 2026-03-02 14:46:28 +00:00
remoteproc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
resctrl Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
reset Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rpmsg Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rtc RTC for 7.0 2026-02-22 09:43:11 -08:00
s390 Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
sbus Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
scsi SCSI fixes on 20260307 2026-03-07 14:04:50 -08:00
sh Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
siox Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
slimbus Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
soc Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
soundwire Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
spi spi: spi-dw-dma: fix print error log when wait finish transaction 2026-03-02 22:33:32 +00:00
spmi Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ssb Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
staging Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
target scsi: target: Fix recursive locking in __configfs_open_file() 2026-02-28 20:41:52 -05:00
tc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
tee Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
thermal Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
thunderbolt Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
tty Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
ufs scsi: ufs: core: Fix shift out of bounds when MAXQ=32 2026-02-24 14:23:07 -05:00
uio Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
usb Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
vdpa Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
vfio Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
vhost Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
video fbdev: au1100fb: Fix build on MIPS64 2026-03-05 17:35:12 +01:00
virt Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses 2026-02-22 08:26:33 -08:00
virtio Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
w1 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
watchdog Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
xen xen: branch for v7.0-rc3 2026-03-07 07:44:32 -08:00
zorro Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
Kconfig
Makefile phy: enter drivers/phy/Makefile even without CONFIG_GENERIC_PHY 2026-02-04 20:45:26 +05:30