[PATCH v2 1/4] ACPI: GTDT: Generate platform devices for MMIO timers
From: Marc Zyngier <maz@kernel.org>
Date: 2025-08-14 15:46:28
Also in:
linux-acpi, lkml
Subsystem:
acpi, the rest · Maintainers:
"Rafael J. Wysocki", Linus Torvalds
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 <redacted> Reviewed-by: Sudeep Holla <redacted> Link: https://lore.kernel.org/r/20250807160243.1970533-2-maz@kernel.org (local) 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