Add helpers to issue reset commands through the PWR_CONTROL interface and wait for reset completion using IRQ signaling. This enables support for both RESET_SOFT and RESET_FAST operations with timeout handling and status verification.
Signed-off-by: Karunika Choo <[email protected]> --- drivers/gpu/drm/panthor/panthor_pwr.c | 62 ++++++++++++++++++++++++++- drivers/gpu/drm/panthor/panthor_pwr.h | 2 + 2 files changed, 63 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panthor/panthor_pwr.c b/drivers/gpu/drm/panthor/panthor_pwr.c index 594181aba847..ecb278824d06 100644 --- a/drivers/gpu/drm/panthor/panthor_pwr.c +++ b/drivers/gpu/drm/panthor/panthor_pwr.c @@ -3,6 +3,7 @@ #include <linux/platform_device.h> #include <linux/interrupt.h> +#include <linux/cleanup.h> #include <linux/iopoll.h> #include <linux/wait.h> @@ -31,6 +32,8 @@ #define PWR_RETRACT_TIMEOUT_US 2000 +#define PWR_RESET_TIMEOUT_MS 500 + /** * struct panthor_pwr - PWR_CONTROL block management data. */ @@ -80,6 +83,42 @@ static void panthor_pwr_write_command(struct panthor_device *ptdev, u32 command, gpu_write(ptdev, PWR_COMMAND, command); } +static bool reset_irq_raised(struct panthor_device *ptdev) +{ + return gpu_read(ptdev, PWR_INT_RAWSTAT) & PWR_IRQ_RESET_COMPLETED; +} + +static bool reset_completed(struct panthor_device *ptdev) +{ + return (ptdev->pwr->pending_reqs & PWR_IRQ_RESET_COMPLETED); +} + +static int panthor_pwr_reset(struct panthor_device *ptdev, u32 reset_cmd) +{ + scoped_guard(spinlock_irqsave, &ptdev->pwr->reqs_lock) { + if (!drm_WARN_ON(&ptdev->base, !reset_completed(ptdev))) { + ptdev->pwr->pending_reqs |= PWR_IRQ_RESET_COMPLETED; + gpu_write(ptdev, PWR_INT_CLEAR, PWR_IRQ_RESET_COMPLETED); + panthor_pwr_write_command(ptdev, reset_cmd, 0); + } + } + + if (!wait_event_timeout(ptdev->pwr->reqs_acked, reset_completed(ptdev), + msecs_to_jiffies(PWR_RESET_TIMEOUT_MS))) { + guard(spinlock_irqsave)(&ptdev->pwr->reqs_lock); + + if (!reset_completed(ptdev) && !reset_irq_raised(ptdev)) { + drm_err(&ptdev->base, "RESET_%s timed out", + reset_cmd == PWR_COMMAND_RESET_SOFT ? "SOFT" : "FAST"); + return -ETIMEDOUT; + } + + ptdev->pwr->pending_reqs &= ~PWR_IRQ_RESET_COMPLETED; + } + + return 0; +} + static const char *get_domain_name(u8 domain) { switch (domain) { @@ -407,9 +446,30 @@ int panthor_pwr_init(struct panthor_device *ptdev) return 0; } +int panthor_pwr_reset_fast(struct panthor_device *ptdev) +{ + if (!ptdev->pwr) + return 0; + + if (!(panthor_pwr_read_status(ptdev) & PWR_STATUS_ALLOW_FAST_RESET)) { + drm_err(&ptdev->base, "RESET_SOFT not allowed"); + return -EOPNOTSUPP; + } + + return panthor_pwr_reset(ptdev, PWR_COMMAND_RESET_FAST); +} + int panthor_pwr_reset_soft(struct panthor_device *ptdev) { - return 0; + if (!ptdev->pwr) + return 0; + + if (!(panthor_pwr_read_status(ptdev) & PWR_STATUS_ALLOW_SOFT_RESET)) { + drm_err(&ptdev->base, "RESET_SOFT not allowed"); + return -EOPNOTSUPP; + } + + return panthor_pwr_reset(ptdev, PWR_COMMAND_RESET_SOFT); } int panthor_pwr_l2_power_off(struct panthor_device *ptdev) diff --git a/drivers/gpu/drm/panthor/panthor_pwr.h b/drivers/gpu/drm/panthor/panthor_pwr.h index a4042c125448..2301c26dab86 100644 --- a/drivers/gpu/drm/panthor/panthor_pwr.h +++ b/drivers/gpu/drm/panthor/panthor_pwr.h @@ -10,6 +10,8 @@ void panthor_pwr_unplug(struct panthor_device *ptdev); int panthor_pwr_init(struct panthor_device *ptdev); +int panthor_pwr_reset_fast(struct panthor_device *ptdev); + int panthor_pwr_reset_soft(struct panthor_device *ptdev); int panthor_pwr_l2_power_on(struct panthor_device *ptdev); -- 2.49.0
