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authorDinh Nguyen <dinguyen@kernel.org>2020-12-05 04:52:23 -0600
committerDaniel Lezcano <daniel.lezcano@linaro.org>2020-12-05 19:33:55 +0100
commit5d9814df0aec56a638bbf20795abb4cfaf3cd331 (patch)
tree507e92555147562b03cfdff83ee06eefd35d4162 /drivers/clocksource
parentfef92cd2bc04c64bb3743d40c0b4be47aedf9e23 (diff)
clocksource/drivers/dw_apb_timer_of: Add error handling if no clock available
commit ("b0fc70ce1f02 arm64: berlin: Select DW_APB_TIMER_OF") added the support for the dw_apb_timer into the arm64 defconfig. However, for some platforms like the Intel Stratix10 and Agilex, the clock manager doesn't get loaded until after the timer driver get loaded. Thus, the driver hits the panic "No clock nor clock-frequency property for" because it cannot properly get the clock. This patch adds the error handling needed for the timer driver so that the kernel can continue booting instead of just hitting the panic. Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20201205105223.208604-1-dinguyen@kernel.org
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/dw_apb_timer_of.c57
1 files changed, 39 insertions, 18 deletions
diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c
index ab3ddebe8344..42e7e43b8fcd 100644
--- a/drivers/clocksource/dw_apb_timer_of.c
+++ b/drivers/clocksource/dw_apb_timer_of.c
@@ -14,12 +14,13 @@
#include <linux/reset.h>
#include <linux/sched_clock.h>
-static void __init timer_get_base_and_rate(struct device_node *np,
+static int __init timer_get_base_and_rate(struct device_node *np,
void __iomem **base, u32 *rate)
{
struct clk *timer_clk;
struct clk *pclk;
struct reset_control *rstc;
+ int ret;
*base = of_iomap(np, 0);
@@ -46,55 +47,67 @@ static void __init timer_get_base_and_rate(struct device_node *np,
pr_warn("pclk for %pOFn is present, but could not be activated\n",
np);
+ if (!of_property_read_u32(np, "clock-freq", rate) &&
+ !of_property_read_u32(np, "clock-frequency", rate))
+ return 0;
+
timer_clk = of_clk_get_by_name(np, "timer");
if (IS_ERR(timer_clk))
- goto try_clock_freq;
+ return PTR_ERR(timer_clk);
- if (!clk_prepare_enable(timer_clk)) {
- *rate = clk_get_rate(timer_clk);
- return;
- }
+ ret = clk_prepare_enable(timer_clk);
+ if (ret)
+ return ret;
+
+ *rate = clk_get_rate(timer_clk);
+ if (!(*rate))
+ return -EINVAL;
-try_clock_freq:
- if (of_property_read_u32(np, "clock-freq", rate) &&
- of_property_read_u32(np, "clock-frequency", rate))
- panic("No clock nor clock-frequency property for %pOFn", np);
+ return 0;
}
-static void __init add_clockevent(struct device_node *event_timer)
+static int __init add_clockevent(struct device_node *event_timer)
{
void __iomem *iobase;
struct dw_apb_clock_event_device *ced;
u32 irq, rate;
+ int ret = 0;
irq = irq_of_parse_and_map(event_timer, 0);
if (irq == 0)
panic("No IRQ for clock event timer");
- timer_get_base_and_rate(event_timer, &iobase, &rate);
+ ret = timer_get_base_and_rate(event_timer, &iobase, &rate);
+ if (ret)
+ return ret;
ced = dw_apb_clockevent_init(-1, event_timer->name, 300, iobase, irq,
rate);
if (!ced)
- panic("Unable to initialise clockevent device");
+ return -EINVAL;
dw_apb_clockevent_register(ced);
+
+ return 0;
}
static void __iomem *sched_io_base;
static u32 sched_rate;
-static void __init add_clocksource(struct device_node *source_timer)
+static int __init add_clocksource(struct device_node *source_timer)
{
void __iomem *iobase;
struct dw_apb_clocksource *cs;
u32 rate;
+ int ret;
- timer_get_base_and_rate(source_timer, &iobase, &rate);
+ ret = timer_get_base_and_rate(source_timer, &iobase, &rate);
+ if (ret)
+ return ret;
cs = dw_apb_clocksource_init(300, source_timer->name, iobase, rate);
if (!cs)
- panic("Unable to initialise clocksource device");
+ return -EINVAL;
dw_apb_clocksource_start(cs);
dw_apb_clocksource_register(cs);
@@ -106,6 +119,8 @@ static void __init add_clocksource(struct device_node *source_timer)
*/
sched_io_base = iobase + 0x04;
sched_rate = rate;
+
+ return 0;
}
static u64 notrace read_sched_clock(void)
@@ -146,10 +161,14 @@ static struct delay_timer dw_apb_delay_timer = {
static int num_called;
static int __init dw_apb_timer_init(struct device_node *timer)
{
+ int ret = 0;
+
switch (num_called) {
case 1:
pr_debug("%s: found clocksource timer\n", __func__);
- add_clocksource(timer);
+ ret = add_clocksource(timer);
+ if (ret)
+ return ret;
init_sched_clock();
#ifdef CONFIG_ARM
dw_apb_delay_timer.freq = sched_rate;
@@ -158,7 +177,9 @@ static int __init dw_apb_timer_init(struct device_node *timer)
break;
default:
pr_debug("%s: found clockevent timer\n", __func__);
- add_clockevent(timer);
+ ret = add_clockevent(timer);
+ if (ret)
+ return ret;
break;
}