[PATCH v3 14/18] ARM: mmp/mmp2: dt: enable the clock

From: Lubomir Rintel
Date: Sun Nov 11 2018 - 22:21:42 EST


The device-tree booted MMP2 needs to enable the timer clock, otherwise
it would stop ticking when the boot finishes.

It can also use the clock rate from the clk, the non-DT boards need to
keep using the hardcoded rates.

Signed-off-by: Lubomir Rintel <lkundrak@xxxxx>
Acked-by: Pavel Machek <pavel@xxxxxx>

---
Changes since v2:
- Wording improvement, whitespace fix and an ack from Pavel

Changes since v1:
- Made the clock optional, to keep compatibility with DTs without it

arch/arm/mach-mmp/common.h | 2 +-
arch/arm/mach-mmp/mmp2.c | 2 +-
arch/arm/mach-mmp/pxa168.c | 2 +-
arch/arm/mach-mmp/time.c | 32 ++++++++++++++++++++------------
4 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/arch/arm/mach-mmp/common.h b/arch/arm/mach-mmp/common.h
index 7e284d9c429f..5ac2851ef5d3 100644
--- a/arch/arm/mach-mmp/common.h
+++ b/arch/arm/mach-mmp/common.h
@@ -2,7 +2,7 @@
#include <linux/reboot.h>
#define ARRAY_AND_SIZE(x) (x), ARRAY_SIZE(x)

-extern void timer_init(int irq);
+extern void timer_init(int irq, unsigned long rate);

extern void __init mmp_map_io(void);
extern void mmp_restart(enum reboot_mode, const char *);
diff --git a/arch/arm/mach-mmp/mmp2.c b/arch/arm/mach-mmp/mmp2.c
index b670fafedeac..8717de7d0757 100644
--- a/arch/arm/mach-mmp/mmp2.c
+++ b/arch/arm/mach-mmp/mmp2.c
@@ -134,7 +134,7 @@ void __init mmp2_timer_init(void)
clk_rst = APBC_APBCLK | APBC_FNCLK | APBC_FNCLKSEL(1);
__raw_writel(clk_rst, APBC_TIMERS);

- timer_init(IRQ_MMP2_TIMER1);
+ timer_init(IRQ_MMP2_TIMER1, 6500000);
}

/* on-chip devices */
diff --git a/arch/arm/mach-mmp/pxa168.c b/arch/arm/mach-mmp/pxa168.c
index 0f5f16fb8c66..77a358165a56 100644
--- a/arch/arm/mach-mmp/pxa168.c
+++ b/arch/arm/mach-mmp/pxa168.c
@@ -79,7 +79,7 @@ void __init pxa168_timer_init(void)
/* 3.25MHz, bus/functional clock enabled, release reset */
__raw_writel(TIMER_CLK_RST, APBC_TIMERS);

- timer_init(IRQ_PXA168_TIMER1);
+ timer_init(IRQ_PXA168_TIMER1, 6500000);
}

void pxa168_clear_keypad_wakeup(void)
diff --git a/arch/arm/mach-mmp/time.c b/arch/arm/mach-mmp/time.c
index 0f49ac579a17..007b94a92923 100644
--- a/arch/arm/mach-mmp/time.c
+++ b/arch/arm/mach-mmp/time.c
@@ -22,6 +22,7 @@
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/clockchips.h>
+#include <linux/clk.h>

#include <linux/io.h>
#include <linux/irq.h>
@@ -38,12 +39,6 @@
#include "cputype.h"
#include "clock.h"

-#ifdef CONFIG_CPU_MMP2
-#define MMP_CLOCK_FREQ 6500000
-#else
-#define MMP_CLOCK_FREQ 3250000
-#endif
-
#define TIMERS_VIRT_BASE TIMERS1_VIRT_BASE

#define MAX_DELTA (0xfffffffe)
@@ -189,19 +184,18 @@ static struct irqaction timer_irq = {
.dev_id = &ckevt,
};

-void __init timer_init(int irq)
+void __init timer_init(int irq, unsigned long rate)
{
timer_config();

- sched_clock_register(mmp_read_sched_clock, 32, MMP_CLOCK_FREQ);
+ sched_clock_register(mmp_read_sched_clock, 32, rate);

ckevt.cpumask = cpumask_of(0);

setup_irq(irq, &timer_irq);

- clocksource_register_hz(&cksrc, MMP_CLOCK_FREQ);
- clockevents_config_and_register(&ckevt, MMP_CLOCK_FREQ,
- MIN_DELTA, MAX_DELTA);
+ clocksource_register_hz(&cksrc, rate);
+ clockevents_config_and_register(&ckevt, rate, MIN_DELTA, MAX_DELTA);
}

#ifdef CONFIG_OF
@@ -213,7 +207,9 @@ static const struct of_device_id mmp_timer_dt_ids[] = {
void __init mmp_dt_init_timer(void)
{
struct device_node *np;
+ struct clk *clk;
int irq, ret;
+ unsigned long rate;

np = of_find_matching_node(NULL, mmp_timer_dt_ids);
if (!np) {
@@ -221,6 +217,18 @@ void __init mmp_dt_init_timer(void)
goto out;
}

+ clk = of_clk_get(np, 0);
+ if (!IS_ERR(clk)) {
+ ret = clk_prepare_enable(clk);
+ if (ret)
+ goto out;
+ rate = clk_get_rate(clk) / 2;
+ } else if (cpu_is_pj4()) {
+ rate = 6500000;
+ } else {
+ rate = 3250000;
+ }
+
irq = irq_of_parse_and_map(np, 0);
if (!irq) {
ret = -EINVAL;
@@ -231,7 +239,7 @@ void __init mmp_dt_init_timer(void)
ret = -ENOMEM;
goto out;
}
- timer_init(irq);
+ timer_init(irq, rate);
return;
out:
pr_err("Failed to get timer from device tree with error:%d\n", ret);
--
2.19.1