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@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));
+ if (IS_ERR(pdev)) {
+ pr_err("Can't register timer %d\n", gwdt_count);
+ continue;
+ }
+
+ mmio_timer_count++;
}
}
if (gwdt_count)
pr_info("found %d SBSA generic Watchdog(s).\n", gwdt_count);
+ if (mmio_timer_count)
+ pr_info("found %d Generic MMIO timer(s).\n", mmio_timer_count);
out_put_gtdt:
acpi_put_table(table);
return ret;
}
-device_initcall(gtdt_sbsa_gwdt_init);
+device_initcall(gtdt_platform_timer_init);
--
2.39.2On 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@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
On Thu, 30 Oct 2025 08:10:31 +0000,
Pavan Kondeti <pavan.kondeti@oss.qualcomm.com> wrote:
>
> 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@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()?
I did. Clearly a brain fart. And looking at this again, there are
additional cleanups that can be applied. I'll spin something shortly.
Thanks,
M.
--
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