Unverified Commit 727538a4 authored by Sarah Walker's avatar Sarah Walker Committed by Maxime Ripard
Browse files

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: default avatarSarah Walker <sarah.walker@imgtec.com>
Signed-off-by: default avatarDonald Robson <donald.robson@imgtec.com>
Reviewed-by: default avatarMaxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/e09af4ef1ff514e1d6d7f97c7c5032c643c56f9c.1700668843.git.donald.robson@imgtec.com


Signed-off-by: default avatarMaxime Ripard <mripard@kernel.org>
parent ff5f643d

drivers/gpu/drm/imagination/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ config DRM_POWERVR 
	tristate "Imagination Technologies PowerVR (Series 6 and later) & IMG Graphics"

	depends on ARM64

	depends on DRM

	depends on PM

	select DRM_GEM_SHMEM_HELPER

	select DRM_SCHED

	select DRM_GPUVM

drivers/gpu/drm/imagination/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ powervr-y := \ 
	pvr_fw.o \

	pvr_gem.o \

	pvr_mmu.o \

	pvr_power.o \

	pvr_vm.o



obj-$(CONFIG_DRM_POWERVR) += powervr.o

drivers/gpu/drm/imagination/pvr_device.c

+21 −2
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#include "pvr_device_info.h"



#include "pvr_fw.h"

#include "pvr_power.h"

#include "pvr_rogue_cr_defs.h"

#include "pvr_vm.h"
@@ -361,6 +362,8 @@ pvr_device_gpu_fini(struct pvr_device *pvr_dev) 
int

pvr_device_init(struct pvr_device *pvr_dev)

{

	struct drm_device *drm_dev = from_pvr_device(pvr_dev);

	struct device *dev = drm_dev->dev;

	int err;



	/* Enable and initialize clocks required for the device to operate. */
@@ -368,13 +371,29 @@ pvr_device_init(struct pvr_device *pvr_dev) 
	if (err)

		return err;



	/* Explicitly power the GPU so we can access control registers before the FW is booted. */

	err = pm_runtime_resume_and_get(dev);

	if (err)

		return err;



	/* Map the control registers into memory. */

	err = pvr_device_reg_init(pvr_dev);

	if (err)

		return err;

		goto err_pm_runtime_put;



	/* Perform GPU-specific initialization steps. */

	return pvr_device_gpu_init(pvr_dev);

	err = pvr_device_gpu_init(pvr_dev);

	if (err)

		goto err_pm_runtime_put;



	pm_runtime_put(dev);



	return 0;



err_pm_runtime_put:

	pm_runtime_put_sync_suspend(dev);



	return err;

}



/**

drivers/gpu/drm/imagination/pvr_device.h

+22 −0
Original line number Diff line number Diff line
@@ -141,6 +141,28 @@ struct pvr_device { 
	 * before submitting the next job.

	 */

	atomic_t mmu_flush_cache_flags;



	struct {

		/** @work: Work item for watchdog callback. */

		struct delayed_work work;



		/** @old_kccb_cmds_executed: KCCB command execution count at last watchdog poll. */

		u32 old_kccb_cmds_executed;



		/** @kccb_stall_count: Number of watchdog polls KCCB has been stalled for. */

		u32 kccb_stall_count;

	} watchdog;



	/**

	 * @lost: %true if the device has been lost.

	 *

	 * This variable is set if the device has become irretrievably unavailable, e.g. if the

	 * firmware processor has stopped responding and can not be revived via a hard reset.

	 */

	bool lost;



	/** @sched_wq: Workqueue for schedulers. */

	struct workqueue_struct *sched_wq;

};



/**

drivers/gpu/drm/imagination/pvr_drv.c

+19 −1
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#include "pvr_drv.h"

#include "pvr_gem.h"

#include "pvr_mmu.h"

#include "pvr_power.h"

#include "pvr_rogue_defs.h"

#include "pvr_rogue_fwif_client.h"

#include "pvr_rogue_fwif_shared.h"
@@ -1265,9 +1266,16 @@ pvr_probe(struct platform_device *plat_dev) 


	platform_set_drvdata(plat_dev, drm_dev);



	devm_pm_runtime_enable(&plat_dev->dev);

	pm_runtime_mark_last_busy(&plat_dev->dev);



	pm_runtime_set_autosuspend_delay(&plat_dev->dev, 50);

	pm_runtime_use_autosuspend(&plat_dev->dev);

	pvr_watchdog_init(pvr_dev);



	err = pvr_device_init(pvr_dev);

	if (err)

		return err;

		goto err_watchdog_fini;



	err = drm_dev_register(drm_dev, 0);

	if (err)
@@ -1278,6 +1286,9 @@ pvr_probe(struct platform_device *plat_dev) 
err_device_fini:

	pvr_device_fini(pvr_dev);



err_watchdog_fini:

	pvr_watchdog_fini(pvr_dev);



	return err;

}
@@ -1287,8 +1298,10 @@ pvr_remove(struct platform_device *plat_dev) 
	struct drm_device *drm_dev = platform_get_drvdata(plat_dev);

	struct pvr_device *pvr_dev = to_pvr_device(drm_dev);



	pm_runtime_suspend(drm_dev->dev);

	pvr_device_fini(pvr_dev);

	drm_dev_unplug(drm_dev);

	pvr_watchdog_fini(pvr_dev);



	return 0;

}
@@ -1299,11 +1312,16 @@ static const struct of_device_id dt_match[] = { 
};

MODULE_DEVICE_TABLE(of, dt_match);



static const struct dev_pm_ops pvr_pm_ops = {

	RUNTIME_PM_OPS(pvr_power_device_suspend, pvr_power_device_resume, pvr_power_device_idle)

};



static struct platform_driver pvr_driver = {

	.probe = pvr_probe,

	.remove = pvr_remove,

	.driver = {

		.name = PVR_DRIVER_NAME,

		.pm = &pvr_pm_ops,

		.of_match_table = dt_match,

	},

};