MIPS: make cp0 counter clocksource/event usable as fallback.

The current mips clock build infrastructure lets a system only use
either the MIPS cp0 counter or a SoC specific timer as a clocksource /
clockevent device.

This patch renames the core cp0 counter clocksource / clockevent functions
from mips_* to r4k_* and updates the wrappers in asm-mips/time.h to
call these renamed functions instead.

Chips which can detect whether it is safe to use a chip-specific timer
can now fall back on the cp0 counter if necessary and possible
(e.g. Alchemy with a follow-on patch).

Existing behaviour is not changed in any way.

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 16 insertions, 8 deletions

diff --git a/arch/mips/include/asm/time.h b/arch/mips/include/asm/time.h
index 9601ea9..38a30d2 100644
--- a/arch/mips/include/asm/time.h
+++ b/arch/mips/include/asm/time.h
@@ -50,27 +50,35 @@ extern int (*perf_irq)(void);
 /*
  * Initialize the calling CPU's compare interrupt as clockevent device
  */
-#ifdef CONFIG_CEVT_R4K
-extern int mips_clockevent_init(void);
+#ifdef CONFIG_CEVT_R4K_LIB
 extern unsigned int __weak get_c0_compare_int(void);
-#else
+extern int r4k_clockevent_init(void);
+#endif
+
 static inline int mips_clockevent_init(void)
 {
+#ifdef CONFIG_CEVT_R4K
+	return r4k_clockevent_init();
+#else
 	return -ENXIO;
-}
 #endif
+}
 
 /*
  * Initialize the count register as a clocksource
  */
-#ifdef CONFIG_CSRC_R4K
-extern int init_mips_clocksource(void);
-#else
+#ifdef CONFIG_CSRC_R4K_LIB
+extern int init_r4k_clocksource(void);
+#endif
+
 static inline int init_mips_clocksource(void)
 {
+#ifdef CONFIG_CSRC_R4K
+	return init_r4k_clocksource();
+#else
 	return 0;
-}
 #endif
+}
 
 extern void clocksource_set_clock(struct clocksource *cs, unsigned int clock);
 extern void clockevent_set_clock(struct clock_event_device *cd,