Re: [PATCH] clocksource/drivers/timer-sun4i: Partially convert to a platform driver

[Samuel Holland]

On 2024-03-13 9:43 AM, Daniel Lezcano wrote:
> On 12/03/2024 20:25, Samuel Holland wrote:
>> Commit 8ec99b033147 ("irqchip/sifive-plic: Convert PLIC driver into a
>> platform driver") broke the MMIO timer on the Allwinner D1 SoC because
>> the IRQ domain is no longer available when timer_probe() is called:
> 
> Did you mean: s/no longer available/not yet available/ ?

I mean that, before this commit, the IRQ domain was available during
timer_probe(); but after this commit, the IRQ domain is not available during
timer_probe().

>>    [    0.000000] irq: no irq domain found for interrupt-controller@10000000 !
>>    [    0.000000] Failed to map interrupt for /soc/timer@2050000
>>    [    0.000000] Failed to initialize '/soc/timer@2050000': -22
>>
>> Fix this by wrapping the timer initialization in a platform driver.
>> builtin_platform_driver_probe() must be used because the driver uses
>> timer_of_init(), which is marked as __init. Only convert the sun8i
>> variants of the hardware, because some older SoCs still need the timer
>> probed early for sched_clock().
>>
>> Fixes: 8ec99b033147 ("irqchip/sifive-plic: Convert PLIC driver into a platform
>> driver")
>> Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx>
>> ---
>>
>>   drivers/clocksource/timer-sun4i.c | 24 ++++++++++++++++++++----
>>   1 file changed, 20 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/clocksource/timer-sun4i.c
>> b/drivers/clocksource/timer-sun4i.c
>> index 7bdcc60ad43c..728dac2baa84 100644
>> --- a/drivers/clocksource/timer-sun4i.c
>> +++ b/drivers/clocksource/timer-sun4i.c
>> @@ -20,6 +20,7 @@
>>   #include <linux/of.h>
>>   #include <linux/of_address.h>
>>   #include <linux/of_irq.h>
>> +#include <linux/platform_device.h>
>>     #include "timer-of.h"
>>   @@ -218,9 +219,24 @@ static int __init sun4i_timer_init(struct device_node
>> *node)
>>   }
>>   TIMER_OF_DECLARE(sun4i, "allwinner,sun4i-a10-timer",
>>                  sun4i_timer_init);
>> -TIMER_OF_DECLARE(sun8i_a23, "allwinner,sun8i-a23-timer",
>> -         sun4i_timer_init);
>> -TIMER_OF_DECLARE(sun8i_v3s, "allwinner,sun8i-v3s-timer",
>> -         sun4i_timer_init);
>>   TIMER_OF_DECLARE(suniv, "allwinner,suniv-f1c100s-timer",
>>                  sun4i_timer_init);
>> +
>> +static int __init sun4i_timer_probe(struct platform_device *pdev)
>> +{
>> +    return sun4i_timer_init(dev_of_node(&pdev->dev));
>> +}
>> +
>> +static const struct of_device_id sun4i_timer_of_match[] = {
>> +    { .compatible = "allwinner,sun8i-a23-timer" },
>> +    { .compatible = "allwinner,sun8i-v3s-timer" },
>> +    { /* sentinel */ }
>> +};
>> +
>> +static struct platform_driver sun4i_timer_driver = {
>> +    .driver    = {
>> +        .name        = "sun4i-timer",
>> +        .of_match_table    = sun4i_timer_of_match,
>> +    },
>> +};
>> +builtin_platform_driver_probe(sun4i_timer_driver, sun4i_timer_probe);
>