Re: [PATCH v20 16/17] clocksource/drivers/arm_arch_timer: Add GTDT support for memory-mapped timer

Hanjun Guo
2017-01-19T12:42:59Z

On 2017/1/19 18:02, Fu Wei wrote:
> Hi Hanjun,
>
> On 19 January 2017 at 17:16, Hanjun Guo <hanjun.guo@linaro.org> wrote:
>> On 2017/1/18 21:25, fu.wei@linaro.org wrote:
>>>
>>> From: Fu Wei <fu.wei@linaro.org>
>>>
>>> The patch add memory-mapped timer register support by using the
>>> information provided by the new GTDT driver of ACPI.
>>>
>>> Signed-off-by: Fu Wei <fu.wei@linaro.org>
>>> ---
>>> drivers/clocksource/arm_arch_timer.c | 35
>>> ++++++++++++++++++++++++++++++++---
>>> 1 file changed, 32 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/clocksource/arm_arch_timer.c
>>> b/drivers/clocksource/arm_arch_timer.c
>>> index 79dc004..7ca2da7 100644
>>> --- a/drivers/clocksource/arm_arch_timer.c
>>> +++ b/drivers/clocksource/arm_arch_timer.c
>>> @@ -1077,10 +1077,36 @@ CLOCKSOURCE_OF_DECLARE(armv7_arch_timer_mem,
>>> "arm,armv7-timer-mem",
>>> arch_timer_mem_of_init);
>>>
>>> #ifdef CONFIG_ACPI_GTDT
>>> -/* Initialize per-processor generic timer */
>>> +static int __init arch_timer_mem_acpi_init(int platform_timer_count)
>>> +{
>>> + struct arch_timer_mem *timer_mem;
>>> + int timer_count, i, ret;
>>> +
>>
>>
>> if (!platform_timer_count)
>> return 0;
>>
>> Did I miss something?
>
> Ah, thanks, I guess I miss this check below.
>
>>
>> Thanks
>> Hanjun
>>
>>
>>> + timer_mem = kcalloc(platform_timer_count, sizeof(*timer_mem),
>>> + GFP_KERNEL);
>>> + if (!timer_mem)
>>> + return -ENOMEM;
>>> +
>>> + ret = acpi_arch_timer_mem_init(timer_mem, &timer_count);
>>> + if (ret || !timer_count)
>>> + goto error;
>>> +
>>> + for (i = 0; i < timer_count; i++) {
>>> + ret = arch_timer_mem_init(timer_mem);
>>> + if (!ret)
>>> + break;
>>> + timer_mem++;
>>> + }
>>> +
>>> +error:
>>> + kfree(timer_mem);
>>> + return ret;
>>> +}
>>> +
>>> +/* Initialize per-processor generic timer and memory-mapped timer(if
>>> present) */
>>> static int __init arch_timer_acpi_init(struct acpi_table_header *table)
>>> {
>>> - int ret;
>>> + int ret, platform_timer_count;
>>>
>>> if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
>>> pr_warn("already initialized, skipping\n");
>>> @@ -1089,7 +1115,7 @@ static int __init arch_timer_acpi_init(struct
>>> acpi_table_header *table)
>>>
>>> arch_timers_present |= ARCH_TIMER_TYPE_CP15;
>>>
>>> - ret = acpi_gtdt_init(table, NULL);
>>> + ret = acpi_gtdt_init(table, &platform_timer_count);
>>> if (ret) {
>>> pr_err("Failed to init GTDT table.\n");
>>> return ret;
>>> @@ -1122,6 +1148,9 @@ static int __init arch_timer_acpi_init(struct
>>> acpi_table_header *table)
>>> if (ret)
>>> return ret;
>>>
>>> + if (arch_timer_mem_acpi_init(platform_timer_count))
>
> + if (platform_timer_count &&
> + arch_timer_mem_acpi_init(platform_timer_count))

It's better.

Thanks
Hanjun