OMAP device has 32k-sync timer which is currently used as a
clocksource in the kernel (omap2plus_defconfig).
The current implementation uses compile time selection between
gp-timer and 32k-sync timer, which breaks multi-omap build for
the devices like AM33xx, where 32k-sync timer is not available.
So use hwmod database lookup mechanism, through which at run-time
we can identify availability of 32k-sync timer on the device,
else fall back to gp-timer.
Signed-off-by: Vaibhav Hiremath <hvaibhav@xxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxx>
Cc: Benoit Cousson <b-cousson@xxxxxx>
Cc: Tony Lindgren <tony@xxxxxxxxxxx>
Cc: Paul Walmsley <paul@xxxxxxxxx>
Cc: Tarun Kanti DebBarma <tarun.kanti@xxxxxx>
---
arch/arm/mach-omap2/timer.c | 27 +++++-------
arch/arm/plat-omap/counter_32k.c | 83 +++++++++++++++++++------------------
2 files changed, 54 insertions(+), 56 deletions(-)
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 6eeff0e..b978b39 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -234,21 +234,6 @@ static void __init omap2_gp_clockevent_init(int gptimer_id,
}
/* Clocksource code */
-
-#ifdef CONFIG_OMAP_32K_TIMER
-/*
- * When 32k-timer is enabled, don't use GPTimer for clocksource
- * instead, just leave default clocksource which uses the 32k
- * sync counter. See clocksource setup in plat-omap/counter_32k.c
- */
-
-static void __init omap2_gp_clocksource_init(int unused, const char *dummy)
-{
- omap_init_clocksource_32k();
-}
-
-#else
-
static struct omap_dm_timer clksrc;
/*
@@ -281,6 +266,17 @@ static void __init omap2_gp_clocksource_init(int gptimer_id,
{
int res;
+ /*
+ * First check for availability for 32k-sync timer.
+ *
+ * Return non-zero, means the device doesn't have 32k-sync timer and
+ * execution will fallback to gp-timer.
+ */
+ res = omap_init_clocksource_32k();
+ if (!res)
+ return;
+
+ /* Fall back to gp-timer code */
res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source);
BUG_ON(res);
@@ -295,7 +291,6 @@ static void __init omap2_gp_clocksource_init(int gptimer_id,
pr_err("Could not register clocksource %s\n",
clocksource_gpt.name);
}
-#endif
#define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \
clksrc_nr, clksrc_src) \
diff --git a/arch/arm/plat-omap/counter_32k.c b/arch/arm/plat-omap/counter_32k.c
index 5f0f229..8504bea 100644
--- a/arch/arm/plat-omap/counter_32k.c
+++ b/arch/arm/plat-omap/counter_32k.c
@@ -69,52 +69,55 @@ void read_persistent_clock(struct timespec *ts)
int __init omap_init_clocksource_32k(void)
{
- static char err[] __initdata = KERN_ERR
- "%s: can't register clocksource!\n";
-
- if (cpu_is_omap16xx() || cpu_class_is_omap2()) {
- u32 pbase;
- unsigned long size = SZ_4K;
- void __iomem *base;
- struct clk *sync_32k_ick;
-
- if (cpu_is_omap16xx()) {
- pbase = OMAP16XX_TIMER_32K_SYNCHRONIZED;
- size = SZ_1K;
- } else if (cpu_is_omap2420())
- pbase = OMAP2420_32KSYNCT_BASE + 0x10;
- else if (cpu_is_omap2430())
- pbase = OMAP2430_32KSYNCT_BASE + 0x10;
- else if (cpu_is_omap34xx())
- pbase = OMAP3430_32KSYNCT_BASE + 0x10;
- else if (cpu_is_omap44xx())
- pbase = OMAP4430_32KSYNCT_BASE + 0x10;
- else
+ u32 pbase;
+ unsigned long size = SZ_4K;
+ void __iomem *base;
+ struct clk *sync_32k_ick;
+
+ if (cpu_is_omap16xx()) {
+ pbase = OMAP16XX_TIMER_32K_SYNCHRONIZED;
+ size = SZ_1K;
+ } else if (cpu_class_is_omap2()) {
+ struct omap_hwmod *oh;
+ const char *oh_name = "counter_32k";
+
+ oh = omap_hwmod_lookup(oh_name);
+ if (!oh || oh->slaves_cnt == 0) {
+ pr_err("Could not lookup %s hwmod\n", oh_name);
return -ENODEV;
+ }
+ pbase = oh->slaves[0]->addr->pa_start + 0x10;
+ } else {
+ return -ENODEV;
+ }
- /* For this to work we must have a static mapping in io.c for this area */
- base = ioremap(pbase, size);
- if (!base)
- return -ENODEV;
+ /*
+ * For this to work we must have a static mapping in io.c
+ * for this area
+ */
+ base = ioremap(pbase, size);
+ if (!base)
+ return -ENODEV;
- sync_32k_ick = clk_get(NULL, "omap_32ksync_ick");
- if (!IS_ERR(sync_32k_ick))
- clk_enable(sync_32k_ick);
+ sync_32k_ick = clk_get(NULL, "omap_32ksync_ick");
+ if (!IS_ERR(sync_32k_ick))
+ clk_enable(sync_32k_ick);
- timer_32k_base = base;
+ timer_32k_base = base;
- /*
- * 120000 rough estimate from the calculations in
- * __clocksource_updatefreq_scale.
- */
- clocks_calc_mult_shift(&persistent_mult, &persistent_shift,
- 32768, NSEC_PER_SEC, 120000);
+ /*
+ * 120000 rough estimate from the calculations in
+ * __clocksource_updatefreq_scale.
+ */
+ clocks_calc_mult_shift(&persistent_mult, &persistent_shift,
+ 32768, NSEC_PER_SEC, 120000);
- if (clocksource_mmio_init(base, "32k_counter", 32768, 250, 32,
- clocksource_mmio_readl_up))
- printk(err, "32k_counter");
+ if (clocksource_mmio_init(base, "32k_counter", 32768, 250, 32,
+ clocksource_mmio_readl_up))
+ printk(KERN_ERR "%s: can't register clocksource!\n",
+ "32k_counter");
+
+ setup_sched_clock(omap_32k_read_sched_clock, 32, 32768);
- setup_sched_clock(omap_32k_read_sched_clock, 32, 32768);
- }
return 0;
}
--
1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
