MIPS: Add hook to get C0 performance counter interrupt

The hardware perf event driver and oprofile interpret the global
cp0_perfcount_irq differently: in the hardware perf event driver
it is an offset from MIPS_CPU_IRQ_BASE and in oprofile it is the
actual IRQ number.  This still works most of the time since
MIPS_CPU_IRQ_BASE is usually 0, but is clearly wrong.  Since the
performance counter interrupt may vary from platform to platform
like the C0 timer interrupt, add the optional get_c0_perfcount_int
hook which returns the IRQ number of the performance counter.
The hook should return < 0 if the performance counter interrupt is
shared with the timer.  If the hook is not present, the CPU vector
reported in C0_IntCtl (cp0_perfcount_irq) is used.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Reviewed-by: Qais Yousef <qais.yousef@imgtec.com>
Tested-by: Qais Yousef <qais.yousef@imgtec.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Jeffrey Deans <jeffrey.deans@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7805/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 7 insertions, 16 deletions

diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c
index 7633d30..9466184 100644
--- a/arch/mips/kernel/perf_event_mipsxx.c
+++ b/arch/mips/kernel/perf_event_mipsxx.c
@@ -1613,22 +1613,13 @@ init_hw_perf_events(void)
 		counters = counters_total_to_per_cpu(counters);
 #endif
 
-#ifdef MSC01E_INT_BASE
-	if (cpu_has_veic) {
-		/*
-		 * Using platform specific interrupt controller defines.
-		 */
-		irq = MSC01E_INT_BASE + MSC01E_INT_PERFCTR;
-	} else {
-#endif
-		if ((cp0_perfcount_irq >= 0) &&
-				(cp0_compare_irq != cp0_perfcount_irq))
-			irq = MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
-		else
-			irq = -1;
-#ifdef MSC01E_INT_BASE
-	}
-#endif
+	if (get_c0_perfcount_int)
+		irq = get_c0_perfcount_int();
+	else if ((cp0_perfcount_irq >= 0) &&
+		 (cp0_compare_irq != cp0_perfcount_irq))
+		irq = MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
+	else
+		irq = -1;
 
 	mipspmu.map_raw_event = mipsxx_pmu_map_raw_event;