[PATCH v2 1/4] ACPI: GTDT: Generate platform devices for MMIO timers

[Marc Zyngier <maz@kernel.org>]

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.

Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20250807160243.1970533-2-maz@kernel.org
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);
-- 
2.39.2