[PATCH 1/4] ACPI: GTDT: Generate platform devices for MMIO timers

Pavan Kondeti pavan.kondeti at oss.qualcomm.com
Thu Oct 30 01:10:31 PDT 2025


On Thu, Aug 07, 2025 at 05:02:40PM +0100, Marc Zyngier wrote:
> In preparation for the MMIO timer support code becoming an actual
> driver, mimic what is done for the SBSA watchdog and expose
> a synthetic device for each MMIO timer block.
> 
> Signed-off-by: Marc Zyngier <maz at kernel.org>
> ---
>  drivers/acpi/arm64/gtdt.c | 29 +++++++++++++++++++++++++----
>  1 file changed, 25 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c
> index 70f8290b659de..fd995a1d3d248 100644
> --- a/drivers/acpi/arm64/gtdt.c
> +++ b/drivers/acpi/arm64/gtdt.c
> @@ -388,11 +388,11 @@ static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd,
>  	return 0;
>  }
>  
> -static int __init gtdt_sbsa_gwdt_init(void)
> +static int __init gtdt_platform_timer_init(void)
>  {
>  	void *platform_timer;
>  	struct acpi_table_header *table;
> -	int ret, timer_count, gwdt_count = 0;
> +	int ret, timer_count, gwdt_count = 0, mmio_timer_count = 0;
>  
>  	if (acpi_disabled)
>  		return 0;
> @@ -414,20 +414,41 @@ static int __init gtdt_sbsa_gwdt_init(void)
>  		goto out_put_gtdt;
>  
>  	for_each_platform_timer(platform_timer) {
> +		ret = 0;
> +
>  		if (is_non_secure_watchdog(platform_timer)) {
>  			ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count);
>  			if (ret)
> -				break;
> +				continue;
>  			gwdt_count++;
> +		} else 	if (is_timer_block(platform_timer)) {
> +			struct arch_timer_mem atm = {};
> +			struct platform_device *pdev;
> +
> +			ret = gtdt_parse_timer_block(platform_timer, &atm);
> +			if (ret)
> +				continue;
> +
> +			pdev = platform_device_register_data(NULL, "gtdt-arm-mmio-timer",
> +							     gwdt_count, &atm,
> +							     sizeof(atm));

Did you mean to pass `mmio_timer_count` as the `id` argument to
platform_device_register_data()?


> +			if (IS_ERR(pdev)) {
> +				pr_err("Can't register timer %d\n", gwdt_count);
> +				continue;
> +			}

and here too.

Thanks,
Pavan



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