linux/drivers
Suravee Suthikulpanit 994d6608ef iommu/amd: Remove performance counter pre-initialization test
In early AMD desktop/mobile platforms (during 2013), when the IOMMU
Performance Counter (PMC) support was first introduced in
commit 30861ddc9c ("perf/x86/amd: Add IOMMU Performance Counter
resource management"), there was a HW bug where the counters could not
be accessed. The result was reading of the counter always return zero.

At the time, the suggested workaround was to add a test logic prior
to initializing the PMC feature to check if the counters can be programmed
and read back the same value. This has been working fine until the more
recent desktop/mobile platforms start enabling power gating for the PMC,
which prevents access to the counters. This results in the PMC support
being disabled unnecesarily.

Unfortunatly, there is no documentation of since which generation
of hardware the original PMC HW bug was fixed. Although, it was fixed
soon after the first introduction of the PMC. Base on this, we assume
that the buggy platforms are less likely to be in used, and it should
be relatively safe to remove this legacy logic.

Link: https://lore.kernel.org/linux-iommu/alpine.LNX.3.20.13.2006030935570.3181@monopod.intra.ispras.ru/
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=201753
Cc: Tj (Elloe Linux) <ml.linux@elloe.vision>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Alexander Monakov <amonakov@ispras.ru>
Cc: David Coe <david.coe@live.co.uk>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210409085848.3908-3-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2021-04-15 15:41:22 +02:00
..
accessibility Char/Misc driver patches for 5.12-rc1 2021-02-24 10:25:37 -08:00
acpi Additional ACPI updates for v5.12-rc1 2021-02-25 12:03:13 -08:00
amba
android
ata
atm atm: idt77252: fix null-ptr-dereference 2021-03-08 15:16:30 -08:00
auxdisplay treewide: Miguel has moved 2021-02-26 09:41:03 -08:00
base software node: Fix device_add_software_node() 2021-03-10 15:25:02 +01:00
bcma
block Merge branch 'akpm' (patches from Andrew) 2021-03-14 12:23:34 -07:00
bluetooth TTY/Serial driver changes for 5.12-rc1 2021-02-20 21:28:04 -08:00
bus Char/Misc driver patches for 5.12-rc1 2021-02-24 10:25:37 -08:00
cdrom
char powerpc fixes for 5.12 #2 2021-03-07 13:24:44 -08:00
clk RISC-V Patches for the 5.12 Merge Window 2021-02-26 10:28:35 -08:00
clocksource A small set of clockevent fixes which fell through the cracks 2021-02-22 14:11:36 -08:00
connector
counter
cpufreq cpufreq: blacklist Arm Vexpress platforms in cpufreq-dt-platdev 2021-03-08 16:20:07 +05:30
cpuidle
crypto vio: make remove callback return void 2021-03-02 22:41:23 +11:00
cxl cxl/mem: Fix potential memory leak 2021-02-22 14:44:39 -08:00
dax Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-02-27 08:07:12 -08:00
dca
devfreq Merge branches 'pm-devfreq' and 'pm-tools' 2021-02-15 17:02:04 +01:00
dio
dma dmaengine updates for v5.12-rc1 2021-02-23 15:05:10 -08:00
dma-buf dma-fence: allow signaling drivers to set fence timestamp 2021-02-24 21:05:28 +05:30
edac Merge branch 'edac-misc' into edac-updates-for-v5.12 2021-02-15 10:06:58 +01:00
eisa
extcon
firewire firewire: replace tricky statement by two simple ones 2021-02-09 12:16:20 +01:00
firmware EFI fix for 5.12-rc2 2021-03-14 12:54:56 -07:00
fpga
fsi
gnss
gpio gpiolib: Read "gpio-line-names" from a firmware node 2021-03-08 11:59:17 +01:00
gpu iommu/amd: Move a few prototypes to include/linux/amd-iommu.h 2021-04-07 11:14:55 +02:00
greybus
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid 2021-02-23 14:52:22 -08:00
hsi
hv mm/memory_hotplug: MEMHP_MERGE_RESOURCE -> MHP_MERGE_RESOURCE 2021-02-26 09:41:00 -08:00
hwmon Devicetree updates for v5.12: 2021-02-22 10:05:12 -08:00
hwspinlock hwspinlock: omap: Add support for K3 AM64x SoCs 2021-02-09 11:36:50 -06:00
hwtracing ARM updates for 5.12-rc1: 2021-02-22 14:27:07 -08:00
i2c i2c: exynos5: Preserve high speed master code 2021-02-26 11:47:42 +01:00
i3c I3C for 5.12 2021-02-22 09:52:55 -08:00
ide ide-5.11-2021-02-28 2021-02-28 15:48:25 -08:00
idle
iio - Use the newly introduced 'hot' and 'critical' ops for the acpi 2021-02-22 09:39:11 -08:00
infiniband RDMA/rxe: Fix errant WARN_ONCE in rxe_completer() 2021-03-05 14:15:22 -04:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2021-02-23 14:56:23 -08:00
interconnect
iommu iommu/amd: Remove performance counter pre-initialization test 2021-04-15 15:41:22 +02:00
ipack ipack: Handle a driver without remove callback 2021-02-09 09:48:23 +01:00
irqchip irqchip/ingenic: Add support for the JZ4760 2021-03-09 08:45:17 +00:00
isdn
leds leds: trigger/tty: Use led_set_brightness_sync() from workqueue 2021-03-10 09:27:56 +01:00
lightnvm lightnvm: pblk: Replace guid_copy() with export_guid()/import_guid() 2021-02-14 21:27:24 -07:00
macintosh
mailbox mailbox: arm_mhuv2: Skip calling kfree() with invalid pointer 2021-02-22 13:34:27 -06:00
mcb
md block-5.12-2021-03-12-v2 2021-03-12 13:25:49 -08:00
media media: rkisp1: params: fix wrong bits settings 2021-03-11 11:40:29 +01:00
memory Char/Misc driver patches for 5.12-rc1 2021-02-24 10:25:37 -08:00
memstick
message
mfd Simple Firmware Interface (SFI) support removal for v5.12-rc1 2021-02-24 10:35:29 -08:00
misc Char/misc driver fixes for 5.12-rc3 2021-03-13 12:38:44 -08:00
mmc mmc: cqhci: Fix random crash when remove mmc module/card 2021-03-09 10:00:52 +01:00
most
mtd This pull request contains changes (actually just fixes) for UBIFS 2021-02-21 13:57:08 -08:00
mux
net Merge git://git.kernel.org:/pub/scm/linux/kernel/git/netdev/net 2021-03-09 17:15:56 -08:00
nfc Char/Misc driver patches for 5.12-rc1 2021-02-24 10:25:37 -08:00
ntb NTB: Add support for EPF PCI Non-Transparent Bridge 2021-02-23 14:12:53 -06:00
nubus
nvdimm libnvdimm + device-dax for 5.12 2021-02-24 09:35:54 -08:00
nvme nvme: fix the nsid value to print in nvme_validate_or_alloc_ns 2021-03-12 13:17:45 -07:00
nvmem nvmem: qcom-spmi-sdam: Fix uninitialized pdev pointer 2021-02-05 11:25:52 +01:00
of Char/Misc driver patches for 5.12-rc1 2021-02-24 10:25:37 -08:00
opp opp: Don't drop extra references to OPPs accidentally 2021-03-12 09:26:52 +05:30
parisc
parport
pci xen: branch for v5.12-rc3 2021-03-12 11:34:36 -08:00
pcmcia Merge branch 'pcmcia-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux 2021-02-26 13:54:43 -08:00
perf perf/arm_dmc620_pmu: Fix error return code in dmc620_pmu_device_probe() 2021-03-12 11:30:31 +00:00
phy phy: second round of phy fixes for v5.11 2021-02-10 10:39:23 +01:00
pinctrl RISC-V Patches for the 5.12 Merge Window 2021-02-26 10:28:35 -08:00
platform Additional ACPI updates for v5.12-rc1 2021-02-25 12:03:13 -08:00
pnp
power
powercap powercap/drivers/dtpm: Add the experimental label to the option description 2021-03-01 17:43:29 +01:00
pps
ps3
ptp ptp: ptp_clockmatrix: clean-up - parenthesis around a == b are unnecessary 2021-02-17 13:49:26 -08:00
pwm pwm: Changes for v5.12-rc1 2021-02-25 12:23:49 -08:00
rapidio
ras
regulator regulator: mt6315: Fix off-by-one for .n_voltages 2021-03-11 13:23:21 +00:00
remoteproc remoteproc: qcom: pas: Add SM8350 PAS remoteprocs 2021-02-11 12:52:18 -06:00
reset RISC-V Patches for the 5.12 Merge Window 2021-02-26 10:28:35 -08:00
rpmsg
rtc Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-02-27 08:07:12 -08:00
s390 block-5.12-2021-03-12-v2 2021-03-12 13:25:49 -08:00
sbus
scsi SCSI fixes on 20210312 2021-03-12 13:37:18 -08:00
sh
siox
slimbus
soc OpenRISC updates for 5.12 2021-02-26 14:16:06 -08:00
soundwire ALSA: hda: move Intel SoundWire ACPI scan to dedicated module 2021-03-02 15:33:00 +01:00
spi powerpc updates for 5.12 2021-02-22 14:34:00 -08:00
spmi spmi: spmi-pmic-arb: Fix hw_irq overflow 2021-02-12 12:26:46 +01:00
ssb
staging Revert "staging: wfx: remove unused included header files" 2021-03-10 09:23:30 +01:00
target SCSI misc on 20210228 2021-02-28 11:51:20 -08:00
tc
tee Simplify i2c acess in OP-TEE driver 2021-02-09 16:10:49 +01:00
thermal - Use the newly introduced 'hot' and 'critical' ops for the acpi 2021-02-22 09:39:11 -08:00
thunderbolt thunderbolt: Changes for v5.12 merge window 2021-02-09 13:00:07 +01:00
tty TTY/Serial fixes for 5.12-rc3 2021-03-13 12:34:29 -08:00
uio uio: uio_pci_generic: don't fail probe if pdev->irq equals to IRQ_NOTCONNECTED 2021-02-09 12:25:32 +01:00
usb USB fixes for 5.12-rc3 2021-03-13 12:32:57 -08:00
vdpa vdpa/mlx5: fix param validation in mlx5_vdpa_get_config() 2021-02-23 07:52:59 -05:00
vfio VFIO updates for v5.12-rc1 2021-02-24 10:43:40 -08:00
vhost virtio: features, fixes 2021-02-25 12:21:08 -08:00
video fbdev: atyfb: use LCD management functions for PPC_PMAC also 2021-03-11 11:11:32 +01:00
virt virt: acrn: Correct type casting of argument of copy_from_user() 2021-03-10 16:59:50 +01:00
virtio Merge branch 'akpm' (patches from Andrew) 2021-02-26 09:50:09 -08:00
visorbus
vlynq
vme vme: make remove callback return void 2021-02-09 12:15:07 +01:00
w1
watchdog Char/Misc driver patches for 5.12-rc1 2021-02-24 10:25:37 -08:00
xen xen: branch for v5.12-rc3 2021-03-12 11:34:36 -08:00
zorro
Kconfig cxl/mem: Introduce a driver for CXL-2.0-Type-3 endpoints 2021-02-16 20:36:38 -08:00
Makefile Simple Firmware Interface (SFI) support removal for v5.12-rc1 2021-02-24 10:35:29 -08:00