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>
diff --git a/arch/mips/ralink/irq.c b/arch/mips/ralink/irq.c
index 0495011..7634dcd 100644
--- a/arch/mips/ralink/irq.c
+++ b/arch/mips/ralink/irq.c
@@ -45,6 +45,7 @@
#define RALINK_INTC_IRQ_PERFC (RALINK_INTC_IRQ_BASE + 9)
static void __iomem *rt_intc_membase;
+static int rt_perfcount_irq;
static inline void rt_intc_w32(u32 val, unsigned reg)
{
@@ -73,6 +74,11 @@
.irq_mask_ack = ralink_intc_irq_mask,
};
+int get_c0_perfcount_int(void)
+{
+ return rt_perfcount_irq;
+}
+
unsigned int get_c0_compare_int(void)
{
return CP0_LEGACY_COMPARE_IRQ;
@@ -167,7 +173,7 @@
irq_set_handler_data(irq, domain);
/* tell the kernel which irq is used for performance monitoring */
- cp0_perfcount_irq = irq_create_mapping(domain, 9);
+ rt_perfcount_irq = irq_create_mapping(domain, 9);
return 0;
}
