On Tue, Aug 6, 2019 at 7:35 AM Robin Murphy [off-list ref] wrote:

On 06/08/2019 15:01, Vasily Khoruzhick wrote:

quoted

Looks like PMU in A64 is broken, it generates no interrupts at all and
as result 'perf top' shows no events.

Does something like 'perf stat sleep 1' at least count cycles correctly?
It could well just be that the interrupt numbers are wrong...

Looks like it does, at least result looks plausible:

$ perf stat sleep 1

Performance counter stats for 'sleep 1':

             4.08 msec task-clock:u              #    0.004 CPUs
utilized
                0      context-switches:u        #    0.000 K/sec
                0      cpu-migrations:u          #    0.000 K/sec
               55      page-faults:u             #    0.013 M/sec
          527,711      cycles:u                  #    0.129 GHz
          197,262      instructions:u            #    0.37  insn per
cycle
           24,242      branches:u                #    5.947 M/sec
            5,083      branch-misses:u           #   20.97% of all
branches

      1.011928625 seconds time elapsed

      0.000000000 seconds user
      0.007196000 seconds sys

quoted

Tested on Pine64-LTS.

Fixes: 34a97fcc71c2 ("arm64: dts: allwinner: a64: Add PMU node")
Cc: Harald Geyer <redacted>
Cc: Jared D. McNeill <redacted>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
---
  arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 9 ---------
  1 file changed, 9 deletions(-)

diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
index 9cc9bdde81ac..cd92f546c483 100644
--- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
+++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi

@@ -142,15 +142,6 @@
              clock-output-names = "ext-osc32k";
      };

-     pmu {
-             compatible = "arm,cortex-a53-pmu";
-             interrupts = <GIC_SPI 152 IRQ_TYPE_LEVEL_HIGH>,
-                          <GIC_SPI 153 IRQ_TYPE_LEVEL_HIGH>,
-                          <GIC_SPI 154 IRQ_TYPE_LEVEL_HIGH>,
-                          <GIC_SPI 155 IRQ_TYPE_LEVEL_HIGH>;

Cross-referencing between some random DTs in the H6 BSP I happen to have
to hand and the A64 User Manual, it looks a lot like someone just forgot
to subtract 32 from these to satisfy the awkward GIC binding - that
wants the SPI index rather than the actual interrupt source number,
which implies these should probably be 120-123 rather than 152-155.

Tried that, didn't work. 'grep pmu /proc/interrupts' shows zeroes, and
'perf top' is completely silent.

Robin.

quoted

-             interrupt-affinity = <&cpu0>, <&cpu1>, <&cpu2>, <&cpu3>;
-     };
-
      psci {
              compatible = "arm,psci-0.2";
              method = "smc";