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authorLinus Torvalds <torvalds@linux-foundation.org>2020-07-25 23:27:12 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-07-25 23:27:12 +0300
commita7b36c2b134f7ca75789d174b97d07acccbf6b93 (patch)
tree6985822140c5849b7d2d008dc0d5615f8693375a /drivers
parent3077805eebb63d75ad716e36777a54a3321d34a5 (diff)
parentb4a25fb0e62990df467451744b22e0e24960a5e6 (diff)
downloadlinux-a7b36c2b134f7ca75789d174b97d07acccbf6b93.tar.xz
Merge tag 'timers-urgent-2020-07-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull timer fix from Ingo Molnar: "Fix a suspend/resume regression (crash) on TI AM3/AM4 SoC's" * tag 'timers-urgent-2020-07-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/drivers/timer-ti-dm: Fix suspend and resume for am3 and am4
Diffstat (limited to 'drivers')
-rw-r--r--drivers/bus/ti-sysc.c22
-rw-r--r--drivers/clocksource/timer-ti-dm-systimer.c46
2 files changed, 58 insertions, 10 deletions
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
index 4f513fa3362f..191c97b84715 100644
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -2865,6 +2865,24 @@ static int sysc_check_disabled_devices(struct sysc *ddata)
return error;
}
+/*
+ * Ignore timers tagged with no-reset and no-idle. These are likely in use,
+ * for example by drivers/clocksource/timer-ti-dm-systimer.c. If more checks
+ * are needed, we could also look at the timer register configuration.
+ */
+static int sysc_check_active_timer(struct sysc *ddata)
+{
+ if (ddata->cap->type != TI_SYSC_OMAP2_TIMER &&
+ ddata->cap->type != TI_SYSC_OMAP4_TIMER)
+ return 0;
+
+ if ((ddata->cfg.quirks & SYSC_QUIRK_NO_RESET_ON_INIT) &&
+ (ddata->cfg.quirks & SYSC_QUIRK_NO_IDLE))
+ return -EBUSY;
+
+ return 0;
+}
+
static const struct of_device_id sysc_match_table[] = {
{ .compatible = "simple-bus", },
{ /* sentinel */ },
@@ -2921,6 +2939,10 @@ static int sysc_probe(struct platform_device *pdev)
if (error)
return error;
+ error = sysc_check_active_timer(ddata);
+ if (error)
+ return error;
+
error = sysc_get_clocks(ddata);
if (error)
return error;
diff --git a/drivers/clocksource/timer-ti-dm-systimer.c b/drivers/clocksource/timer-ti-dm-systimer.c
index 6fd1f219a512..f6fd1c1cc527 100644
--- a/drivers/clocksource/timer-ti-dm-systimer.c
+++ b/drivers/clocksource/timer-ti-dm-systimer.c
@@ -19,7 +19,7 @@
/* For type1, set SYSC_OMAP2_CLOCKACTIVITY for fck off on idle, l4 clock on */
#define DMTIMER_TYPE1_ENABLE ((1 << 9) | (SYSC_IDLE_SMART << 3) | \
SYSC_OMAP2_ENAWAKEUP | SYSC_OMAP2_AUTOIDLE)
-
+#define DMTIMER_TYPE1_DISABLE (SYSC_OMAP2_SOFTRESET | SYSC_OMAP2_AUTOIDLE)
#define DMTIMER_TYPE2_ENABLE (SYSC_IDLE_SMART_WKUP << 2)
#define DMTIMER_RESET_WAIT 100000
@@ -44,6 +44,8 @@ struct dmtimer_systimer {
u8 ctrl;
u8 wakeup;
u8 ifctrl;
+ struct clk *fck;
+ struct clk *ick;
unsigned long rate;
};
@@ -298,16 +300,20 @@ static void __init dmtimer_systimer_select_best(void)
}
/* Interface clocks are only available on some SoCs variants */
-static int __init dmtimer_systimer_init_clock(struct device_node *np,
+static int __init dmtimer_systimer_init_clock(struct dmtimer_systimer *t,
+ struct device_node *np,
const char *name,
unsigned long *rate)
{
struct clk *clock;
unsigned long r;
+ bool is_ick = false;
int error;
+ is_ick = !strncmp(name, "ick", 3);
+
clock = of_clk_get_by_name(np, name);
- if ((PTR_ERR(clock) == -EINVAL) && !strncmp(name, "ick", 3))
+ if ((PTR_ERR(clock) == -EINVAL) && is_ick)
return 0;
else if (IS_ERR(clock))
return PTR_ERR(clock);
@@ -320,6 +326,11 @@ static int __init dmtimer_systimer_init_clock(struct device_node *np,
if (!r)
return -ENODEV;
+ if (is_ick)
+ t->ick = clock;
+ else
+ t->fck = clock;
+
*rate = r;
return 0;
@@ -339,7 +350,10 @@ static void dmtimer_systimer_enable(struct dmtimer_systimer *t)
static void dmtimer_systimer_disable(struct dmtimer_systimer *t)
{
- writel_relaxed(0, t->base + t->sysc);
+ if (!dmtimer_systimer_revision1(t))
+ return;
+
+ writel_relaxed(DMTIMER_TYPE1_DISABLE, t->base + t->sysc);
}
static int __init dmtimer_systimer_setup(struct device_node *np,
@@ -366,13 +380,13 @@ static int __init dmtimer_systimer_setup(struct device_node *np,
pr_err("%s: clock source init failed: %i\n", __func__, error);
/* For ti-sysc, we have timer clocks at the parent module level */
- error = dmtimer_systimer_init_clock(np->parent, "fck", &rate);
+ error = dmtimer_systimer_init_clock(t, np->parent, "fck", &rate);
if (error)
goto err_unmap;
t->rate = rate;
- error = dmtimer_systimer_init_clock(np->parent, "ick", &rate);
+ error = dmtimer_systimer_init_clock(t, np->parent, "ick", &rate);
if (error)
goto err_unmap;
@@ -496,12 +510,18 @@ static void omap_clockevent_idle(struct clock_event_device *evt)
struct dmtimer_systimer *t = &clkevt->t;
dmtimer_systimer_disable(t);
+ clk_disable(t->fck);
}
static void omap_clockevent_unidle(struct clock_event_device *evt)
{
struct dmtimer_clockevent *clkevt = to_dmtimer_clockevent(evt);
struct dmtimer_systimer *t = &clkevt->t;
+ int error;
+
+ error = clk_enable(t->fck);
+ if (error)
+ pr_err("could not enable timer fck on resume: %i\n", error);
dmtimer_systimer_enable(t);
writel_relaxed(OMAP_TIMER_INT_OVERFLOW, t->base + t->irq_ena);
@@ -570,8 +590,8 @@ static int __init dmtimer_clockevent_init(struct device_node *np)
3, /* Timer internal resynch latency */
0xffffffff);
- if (of_device_is_compatible(np, "ti,am33xx") ||
- of_device_is_compatible(np, "ti,am43")) {
+ if (of_machine_is_compatible("ti,am33xx") ||
+ of_machine_is_compatible("ti,am43")) {
dev->suspend = omap_clockevent_idle;
dev->resume = omap_clockevent_unidle;
}
@@ -616,12 +636,18 @@ static void dmtimer_clocksource_suspend(struct clocksource *cs)
clksrc->loadval = readl_relaxed(t->base + t->counter);
dmtimer_systimer_disable(t);
+ clk_disable(t->fck);
}
static void dmtimer_clocksource_resume(struct clocksource *cs)
{
struct dmtimer_clocksource *clksrc = to_dmtimer_clocksource(cs);
struct dmtimer_systimer *t = &clksrc->t;
+ int error;
+
+ error = clk_enable(t->fck);
+ if (error)
+ pr_err("could not enable timer fck on resume: %i\n", error);
dmtimer_systimer_enable(t);
writel_relaxed(clksrc->loadval, t->base + t->counter);
@@ -653,8 +679,8 @@ static int __init dmtimer_clocksource_init(struct device_node *np)
dev->mask = CLOCKSOURCE_MASK(32);
dev->flags = CLOCK_SOURCE_IS_CONTINUOUS;
- if (of_device_is_compatible(np, "ti,am33xx") ||
- of_device_is_compatible(np, "ti,am43")) {
+ /* Unlike for clockevent, legacy code sets suspend only for am4 */
+ if (of_machine_is_compatible("ti,am43")) {
dev->suspend = dmtimer_clocksource_suspend;
dev->resume = dmtimer_clocksource_resume;
}