diff options
author | Sarah Walker <sarah.walker@imgtec.com> | 2023-11-22 19:34:33 +0300 |
---|---|---|
committer | Maxime Ripard <mripard@kernel.org> | 2023-11-23 11:01:46 +0300 |
commit | 727538a4bbff07736ecfd704efd7e21718fca3e4 (patch) | |
tree | 5eb5f5382274583f9f3fb5120b1d2eecce4ecfc6 /drivers/gpu/drm/imagination/pvr_power.c | |
parent | ff5f643de0bf27874c4033cd57a0bd034b5c7d11 (diff) | |
download | linux-727538a4bbff07736ecfd704efd7e21718fca3e4.tar.xz |
drm/imagination: Implement power management
Add power management to the driver, using runtime pm. The power off
sequence depends on firmware commands which are not implemented in this
patch.
Changes since v8:
- Corrected license identifiers
Changes since v5:
- Use RUNTIME_PM_OPS() to declare PM callbacks
- Add Kconfig dependency on CONFIG_PM
Changes since v4:
- Suspend runtime PM before unplugging device on rmmod
Changes since v3:
- Don't power device when calling pvr_device_gpu_fini()
- Documentation for pvr_dev->lost has been improved
- pvr_power_init() renamed to pvr_watchdog_init()
- Use drm_dev_{enter,exit}
Changes since v2:
- Use runtime PM
- Implement watchdog
Signed-off-by: Sarah Walker <sarah.walker@imgtec.com>
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/e09af4ef1ff514e1d6d7f97c7c5032c643c56f9c.1700668843.git.donald.robson@imgtec.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Diffstat (limited to 'drivers/gpu/drm/imagination/pvr_power.c')
-rw-r--r-- | drivers/gpu/drm/imagination/pvr_power.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/drivers/gpu/drm/imagination/pvr_power.c b/drivers/gpu/drm/imagination/pvr_power.c new file mode 100644 index 000000000000..88f14a4d31ab --- /dev/null +++ b/drivers/gpu/drm/imagination/pvr_power.c @@ -0,0 +1,271 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* Copyright (c) 2023 Imagination Technologies Ltd. */ + +#include "pvr_device.h" +#include "pvr_fw.h" +#include "pvr_power.h" +#include "pvr_rogue_fwif.h" + +#include <drm/drm_drv.h> +#include <drm/drm_managed.h> +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/timer.h> +#include <linux/types.h> +#include <linux/workqueue.h> + +#define POWER_SYNC_TIMEOUT_US (1000000) /* 1s */ + +#define WATCHDOG_TIME_MS (500) + +static int +pvr_power_send_command(struct pvr_device *pvr_dev, struct rogue_fwif_kccb_cmd *pow_cmd) +{ + /* TODO: implement */ + return -ENODEV; +} + +static int +pvr_power_request_idle(struct pvr_device *pvr_dev) +{ + struct rogue_fwif_kccb_cmd pow_cmd; + + /* Send FORCED_IDLE request to FW. */ + pow_cmd.cmd_type = ROGUE_FWIF_KCCB_CMD_POW; + pow_cmd.cmd_data.pow_data.pow_type = ROGUE_FWIF_POW_FORCED_IDLE_REQ; + pow_cmd.cmd_data.pow_data.power_req_data.pow_request_type = ROGUE_FWIF_POWER_FORCE_IDLE; + + return pvr_power_send_command(pvr_dev, &pow_cmd); +} + +static int +pvr_power_request_pwr_off(struct pvr_device *pvr_dev) +{ + struct rogue_fwif_kccb_cmd pow_cmd; + + /* Send POW_OFF request to firmware. */ + pow_cmd.cmd_type = ROGUE_FWIF_KCCB_CMD_POW; + pow_cmd.cmd_data.pow_data.pow_type = ROGUE_FWIF_POW_OFF_REQ; + pow_cmd.cmd_data.pow_data.power_req_data.forced = true; + + return pvr_power_send_command(pvr_dev, &pow_cmd); +} + +static int +pvr_power_fw_disable(struct pvr_device *pvr_dev, bool hard_reset) +{ + if (!hard_reset) { + int err; + + cancel_delayed_work_sync(&pvr_dev->watchdog.work); + + err = pvr_power_request_idle(pvr_dev); + if (err) + return err; + + err = pvr_power_request_pwr_off(pvr_dev); + if (err) + return err; + } + + /* TODO: stop firmware */ + return -ENODEV; +} + +static int +pvr_power_fw_enable(struct pvr_device *pvr_dev) +{ + int err; + + /* TODO: start firmware */ + err = -ENODEV; + if (err) + return err; + + queue_delayed_work(pvr_dev->sched_wq, &pvr_dev->watchdog.work, + msecs_to_jiffies(WATCHDOG_TIME_MS)); + + return 0; +} + +bool +pvr_power_is_idle(struct pvr_device *pvr_dev) +{ + /* TODO: implement */ + return true; +} + +static bool +pvr_watchdog_kccb_stalled(struct pvr_device *pvr_dev) +{ + /* TODO: implement */ + return false; +} + +static void +pvr_watchdog_worker(struct work_struct *work) +{ + struct pvr_device *pvr_dev = container_of(work, struct pvr_device, + watchdog.work.work); + bool stalled; + + if (pvr_dev->lost) + return; + + if (pm_runtime_get_if_in_use(from_pvr_device(pvr_dev)->dev) <= 0) + goto out_requeue; + + stalled = pvr_watchdog_kccb_stalled(pvr_dev); + + if (stalled) { + drm_err(from_pvr_device(pvr_dev), "FW stalled, trying hard reset"); + + pvr_power_reset(pvr_dev, true); + /* Device may be lost at this point. */ + } + + pm_runtime_put(from_pvr_device(pvr_dev)->dev); + +out_requeue: + if (!pvr_dev->lost) { + queue_delayed_work(pvr_dev->sched_wq, &pvr_dev->watchdog.work, + msecs_to_jiffies(WATCHDOG_TIME_MS)); + } +} + +/** + * pvr_watchdog_init() - Initialise watchdog for device + * @pvr_dev: Target PowerVR device. + * + * Returns: + * * 0 on success, or + * * -%ENOMEM on out of memory. + */ +int +pvr_watchdog_init(struct pvr_device *pvr_dev) +{ + INIT_DELAYED_WORK(&pvr_dev->watchdog.work, pvr_watchdog_worker); + + return 0; +} + +int +pvr_power_device_suspend(struct device *dev) +{ + struct platform_device *plat_dev = to_platform_device(dev); + struct drm_device *drm_dev = platform_get_drvdata(plat_dev); + struct pvr_device *pvr_dev = to_pvr_device(drm_dev); + int idx; + + if (!drm_dev_enter(drm_dev, &idx)) + return -EIO; + + clk_disable_unprepare(pvr_dev->mem_clk); + clk_disable_unprepare(pvr_dev->sys_clk); + clk_disable_unprepare(pvr_dev->core_clk); + + drm_dev_exit(idx); + + return 0; +} + +int +pvr_power_device_resume(struct device *dev) +{ + struct platform_device *plat_dev = to_platform_device(dev); + struct drm_device *drm_dev = platform_get_drvdata(plat_dev); + struct pvr_device *pvr_dev = to_pvr_device(drm_dev); + int idx; + int err; + + if (!drm_dev_enter(drm_dev, &idx)) + return -EIO; + + err = clk_prepare_enable(pvr_dev->core_clk); + if (err) + goto err_drm_dev_exit; + + err = clk_prepare_enable(pvr_dev->sys_clk); + if (err) + goto err_core_clk_disable; + + err = clk_prepare_enable(pvr_dev->mem_clk); + if (err) + goto err_sys_clk_disable; + + drm_dev_exit(idx); + + return 0; + +err_sys_clk_disable: + clk_disable_unprepare(pvr_dev->sys_clk); + +err_core_clk_disable: + clk_disable_unprepare(pvr_dev->core_clk); + +err_drm_dev_exit: + drm_dev_exit(idx); + + return err; +} + +int +pvr_power_device_idle(struct device *dev) +{ + struct platform_device *plat_dev = to_platform_device(dev); + struct drm_device *drm_dev = platform_get_drvdata(plat_dev); + struct pvr_device *pvr_dev = to_pvr_device(drm_dev); + + return pvr_power_is_idle(pvr_dev) ? 0 : -EBUSY; +} + +/** + * pvr_power_reset() - Reset the GPU + * @pvr_dev: Device pointer + * @hard_reset: %true for hard reset, %false for soft reset + * + * If @hard_reset is %false and the FW processor fails to respond during the reset process, this + * function will attempt a hard reset. + * + * If a hard reset fails then the GPU device is reported as lost. + * + * Returns: + * * 0 on success, or + * * Any error code returned by pvr_power_get, pvr_power_fw_disable or pvr_power_fw_enable(). + */ +int +pvr_power_reset(struct pvr_device *pvr_dev, bool hard_reset) +{ + /* TODO: Implement hard reset. */ + int err; + + /* + * Take a power reference during the reset. This should prevent any interference with the + * power state during reset. + */ + WARN_ON(pvr_power_get(pvr_dev)); + + err = pvr_power_fw_disable(pvr_dev, false); + if (err) + goto err_power_put; + + err = pvr_power_fw_enable(pvr_dev); + +err_power_put: + pvr_power_put(pvr_dev); + + return err; +} + +/** + * pvr_watchdog_fini() - Shutdown watchdog for device + * @pvr_dev: Target PowerVR device. + */ +void +pvr_watchdog_fini(struct pvr_device *pvr_dev) +{ + cancel_delayed_work_sync(&pvr_dev->watchdog.work); +} |