linux/arch
Drew Fustini bceaae3bac clocksource/drivers/timer-ti-dm: Fix regression from errata i940 fix
The existing fix for errata i940 causes a conflict for IPU2 which is
using timer 3 and 4. From arch/arm/boot/dts/dra7-ipu-dsp-common.dtsi:

  &ipu2 {
          mboxes = <&mailbox6 &mbox_ipu2_ipc3x>;
          ti,timers = <&timer3>;
          ti,watchdog-timers = <&timer4>, <&timer9>;
  };

The conflict was noticed when booting mainline on the BeagleBoard X15
which has a TI AM5728 SoC:

  remoteproc remoteproc1: 55020000.ipu is available
  remoteproc remoteproc1: powering up 55020000.ipu
  remoteproc remoteproc1: Booting fw image dra7-ipu2-fw.xem4
  omap-rproc 55020000.ipu: could not get timer platform device
  omap-rproc 55020000.ipu: omap_rproc_enable_timers failed: -19
  remoteproc remoteproc1: can't start rproc 55020000.ipu: -19

This change modifies the errata fix to instead use timer 15 and 16 which
resolves the timer conflict.

It does not appear to introduce any latency regression. Results from
cyclictest with original errata fix using dmtimer 3 and 4:

  # cyclictest --mlockall --smp --priority=80 --interval=200 --distance=0
  policy: fifo: loadavg: 0.02 0.03 0.05

  T: 0 ( 1449) P:80 I:200 C: 800368 Min:   0 Act:   32 Avg:   22 Max:  128
  T: 1 ( 1450) P:80 I:200 C: 800301 Min:   0 Act:   12 Avg:   23 Max:   70

The results after the change to dmtimer 15 and 16:

  # cyclictest --mlockall --smp --priority=80 --interval=200 --distance=0
  policy: fifo: loadavg: 0.36 0.19 0.07

  T: 0 ( 1711) P:80 I:200 C: 759599 Min:   0 Act:    6 Avg:   22 Max:  108
  T: 1 ( 1712) P:80 I:200 C: 759539 Min:   0 Act:   19 Avg:   23 Max:   79

Fixes: 25de4ce5ed ("clocksource/drivers/timer-ti-dm: Handle dra7 timer wrap errata i940")
Link: https://lore.kernel.org/linux-omap/YfWsG0p6to3IJuvE@x1/
Suggested-by: Suman Anna <s-anna@ti.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Drew Fustini <dfustini@baylibre.com>
Link: https://lore.kernel.org/r/20220204053503.1409162-1-dfustini@baylibre.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2022-03-07 18:27:16 +01:00
..
alpha futex: Wireup futex_waitv syscall 2021-11-25 14:26:12 +01:00
arc Add linux/cacheflush.h 2021-11-17 10:36:15 -05:00
arm clocksource/drivers/timer-ti-dm: Fix regression from errata i940 fix 2022-03-07 18:27:16 +01:00
arm64 pci-v5.16-fixes-2 2021-12-10 11:56:05 -08:00
csky csky: fix typo of fpu config macro 2021-12-08 14:15:54 +08:00
h8300 Kbuild updates for v5.16 2021-11-08 09:15:45 -08:00
hexagon hexagon: ignore vmlinux.lds 2021-11-20 10:35:54 -08:00
ia64 futex: Wireup futex_waitv syscall 2021-11-25 14:26:12 +01:00
m68k asm-generic: syscall table updates 2021-11-25 10:41:28 -08:00
microblaze futex: Wireup futex_waitv syscall 2021-11-25 14:26:12 +01:00
mips Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2021-12-08 16:06:44 -08:00
nds32 Add linux/cacheflush.h 2021-11-17 10:36:15 -05:00
nios2 Add linux/cacheflush.h 2021-11-17 10:36:15 -05:00
openrisc Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2021-11-10 16:15:54 -08:00
parisc parisc: Mark cr16 CPU clocksource unstable on all SMP machines 2021-12-04 21:36:04 +01:00
powerpc powerpc fixes for 5.16 #3 2021-11-27 10:06:15 -08:00
riscv RISC-V: KVM: Fix incorrect KVM_MAX_VCPUS value 2021-11-22 10:36:19 +05:30
s390 s390: update defconfigs 2021-12-02 19:29:44 +01:00
sh asm-generic: syscall table updates 2021-11-25 10:41:28 -08:00
sparc asm-generic: syscall table updates 2021-11-25 10:41:28 -08:00
um Merge branch 'exit-cleanups-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2021-11-10 16:15:54 -08:00
x86 A single fix for the x86 scheduler topology: 2021-12-12 09:38:04 -08:00
xtensa asm-generic: syscall table updates 2021-11-25 10:41:28 -08:00
.gitignore
Kconfig arch: Add generic Kconfig option indicating page size smaller than 64k 2021-11-27 14:34:41 -08:00