[PATCH 2/9] MIPS: Read CPU IRQ line that FDC to routed to

From: James Hogan
Date: Thu Jan 29 2015 - 06:14:45 EST


Read the CPU IRQ line reportedly used for the Fast Debug Channel (FDC)
interrupt from the IntCtl register and store it in cp0_fdc_irq where
platform implementations of the new weak platform function
get_c0_fdc_int() can refer to it.

Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxx
---
arch/mips/include/asm/irq.h | 3 +++
arch/mips/kernel/traps.c | 11 +++++++++++
2 files changed, 14 insertions(+)

diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h
index 5a4e1bb8fb1b..f0db99f8defe 100644
--- a/arch/mips/include/asm/irq.h
+++ b/arch/mips/include/asm/irq.h
@@ -47,6 +47,9 @@ extern void free_irqno(unsigned int irq);
extern int cp0_compare_irq;
extern int cp0_compare_irq_shift;
extern int cp0_perfcount_irq;
+extern int cp0_fdc_irq;
+
+extern int __weak get_c0_fdc_int(void);

void arch_trigger_all_cpu_backtrace(bool);
#define arch_trigger_all_cpu_backtrace arch_trigger_all_cpu_backtrace
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 9c109fd8ba99..290da81c0532 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -1920,6 +1920,12 @@ int cp0_compare_irq_shift;
int cp0_perfcount_irq;
EXPORT_SYMBOL_GPL(cp0_perfcount_irq);

+/*
+ * Fast debug channel IRQ or -1 if not present
+ */
+int cp0_fdc_irq;
+EXPORT_SYMBOL_GPL(cp0_fdc_irq);
+
static int noulri;

static int __init ulri_disable(char *s)
@@ -2001,15 +2007,20 @@ void per_cpu_trap_init(bool is_boot_cpu)
*
* o read IntCtl.IPTI to determine the timer interrupt
* o read IntCtl.IPPCI to determine the performance counter interrupt
+ * o read IntCtl.IPFDC to determine the fast debug channel interrupt
*/
if (cpu_has_mips_r2) {
cp0_compare_irq_shift = CAUSEB_TI - CAUSEB_IP;
cp0_compare_irq = (read_c0_intctl() >> INTCTLB_IPTI) & 7;
cp0_perfcount_irq = (read_c0_intctl() >> INTCTLB_IPPCI) & 7;
+ cp0_fdc_irq = (read_c0_intctl() >> INTCTLB_IPFDC) & 7;
+ if (!cp0_fdc_irq)
+ cp0_fdc_irq = -1;
} else {
cp0_compare_irq = CP0_LEGACY_COMPARE_IRQ;
cp0_compare_irq_shift = CP0_LEGACY_PERFCNT_IRQ;
cp0_perfcount_irq = -1;
+ cp0_fdc_irq = -1;
}

if (!cpu_data[cpu].asid_cache)
--
2.0.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/