Currently it's not possible to use perf on ath79 due to genirq flags
mismatch happening on static virtual IRQ 13 which is used for
performance counters hardware IRQ 5.
On TP-Link Archer C7v5:
CPU0
2: 0 MIPS 2 ath9k
4: 318 MIPS 4 19000000.eth
7: 55034 MIPS 7 timer
8: 1236 MISC 3 ttyS0
12: 0 INTC 1 ehci_hcd:usb1
13: 0 gpio-ath79 2 keys
14: 0 gpio-ath79 5 keys
15: 31 AR724X PCI 1 ath10k_pci
$ perf top
genirq: Flags mismatch irq 13. 00014c83 (mips_perf_pmu) vs. 00002003 (keys)
On TP-Link Archer C7v4:
CPU0
4: 0 MIPS 4 19000000.eth
5: 7135 MIPS 5 1a000000.eth
7: 98379 MIPS 7 timer
8: 30 MISC 3 ttyS0
12: 90028 INTC 0 ath9k
13: 5520 INTC 1 ehci_hcd:usb1
14: 4623 INTC 2 ehci_hcd:usb2
15: 32844 AR724X PCI 1 ath10k_pci
16: 0 gpio-ath79 16 keys
23: 0 gpio-ath79 23 keys
$ perf top
genirq: Flags mismatch irq 13. 00014c80 (mips_perf_pmu) vs. 00000080 (ehci_hcd:usb1)
This problem is happening, because currently statically assigned virtual
IRQ 13 for performance counters is not claimed during the initialization
of MIPS PMU during the bootup, so the IRQ subsystem doesn't know, that
this interrupt isn't available for further use.
So this patch fixes the issue by simply booking hardware IRQ 5 for MIPS PMU.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
78ee6b1a40