Commit c27787f2 authored by Karunika Choo's avatar Karunika Choo Committed by Boris Brezillon
Browse files

drm/panthor: Introduce panthor_pwr API and power control framework 



Add the new panthor_pwr module, which provides basic power control
management for Mali-G1 GPUs. The initial implementation includes
infrastructure for initializing the PWR_CONTROL block, requesting and
handling its IRQ, and checking for PWR_CONTROL support based on GPU
architecture.

The patch also integrates panthor_pwr with the device lifecycle (init,
suspend, resume, and unplug) through the new API functions. It also
registers the IRQ handler under the 'gpu' IRQ as the PWR_CONTROL block
is located within the GPU_CONTROL block.

Reviewed-by: default avatarSteven Price <steven.price@arm.com>
Signed-off-by: default avatarKarunika Choo <karunika.choo@arm.com>
Link: https://patch.msgid.link/20251125125548.3282320-4-karunika.choo@arm.com


Signed-off-by: default avatarBoris Brezillon <boris.brezillon@collabora.com>
parent 7d334f5c

drivers/gpu/drm/panthor/Makefile

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

	panthor_hw.o \

	panthor_mmu.o \

	panthor_pwr.o \

	panthor_sched.o



obj-$(CONFIG_DRM_PANTHOR) += panthor.o

drivers/gpu/drm/panthor/panthor_device.c

+13 −1
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ 
#include "panthor_gpu.h"

#include "panthor_hw.h"

#include "panthor_mmu.h"

#include "panthor_pwr.h"

#include "panthor_regs.h"

#include "panthor_sched.h"
@@ -113,6 +114,7 @@ void panthor_device_unplug(struct panthor_device *ptdev) 
	panthor_fw_unplug(ptdev);

	panthor_mmu_unplug(ptdev);

	panthor_gpu_unplug(ptdev);

	panthor_pwr_unplug(ptdev);



	pm_runtime_dont_use_autosuspend(ptdev->base.dev);

	pm_runtime_put_sync_suspend(ptdev->base.dev);
@@ -268,10 +270,14 @@ int panthor_device_init(struct panthor_device *ptdev) 
	if (ret)

		goto err_rpm_put;



	ret = panthor_gpu_init(ptdev);

	ret = panthor_pwr_init(ptdev);

	if (ret)

		goto err_rpm_put;



	ret = panthor_gpu_init(ptdev);

	if (ret)

		goto err_unplug_pwr;



	ret = panthor_gpu_coherency_init(ptdev);

	if (ret)

		goto err_unplug_gpu;
@@ -312,6 +318,9 @@ int panthor_device_init(struct panthor_device *ptdev) 
err_unplug_gpu:

	panthor_gpu_unplug(ptdev);



err_unplug_pwr:

	panthor_pwr_unplug(ptdev);



err_rpm_put:

	pm_runtime_put_sync_suspend(ptdev->base.dev);

	return ret;
@@ -465,6 +474,7 @@ static int panthor_device_resume_hw_components(struct panthor_device *ptdev) 
{

	int ret;



	panthor_pwr_resume(ptdev);

	panthor_gpu_resume(ptdev);

	panthor_mmu_resume(ptdev);
@@ -474,6 +484,7 @@ static int panthor_device_resume_hw_components(struct panthor_device *ptdev) 


	panthor_mmu_suspend(ptdev);

	panthor_gpu_suspend(ptdev);

	panthor_pwr_suspend(ptdev);

	return ret;

}
@@ -587,6 +598,7 @@ int panthor_device_suspend(struct device *dev) 
		panthor_fw_suspend(ptdev);

		panthor_mmu_suspend(ptdev);

		panthor_gpu_suspend(ptdev);

		panthor_pwr_suspend(ptdev);

		drm_dev_exit(cookie);

	}

drivers/gpu/drm/panthor/panthor_device.h

+4 −0
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ struct panthor_job; 
struct panthor_mmu;

struct panthor_fw;

struct panthor_perfcnt;

struct panthor_pwr;

struct panthor_vm;

struct panthor_vm_pool;
@@ -138,6 +139,9 @@ struct panthor_device { 
	/** @hw: GPU-specific data. */

	struct panthor_hw *hw;



	/** @pwr: Power control management data. */

	struct panthor_pwr *pwr;



	/** @gpu: GPU management data. */

	struct panthor_gpu *gpu;

drivers/gpu/drm/panthor/panthor_hw.h

+6 −0
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
#define __PANTHOR_HW_H__



#include "panthor_device.h"

#include "panthor_regs.h"



/**

 * struct panthor_hw_ops - HW operations that are specific to a GPU
@@ -47,4 +48,9 @@ static inline void panthor_hw_l2_power_off(struct panthor_device *ptdev) 
	ptdev->hw->ops.l2_power_off(ptdev);

}



static inline bool panthor_hw_has_pwr_ctrl(struct panthor_device *ptdev)

{

	return GPU_ARCH_MAJOR(ptdev->gpu_info.gpu_id) >= 14;

}



#endif /* __PANTHOR_HW_H__ */

drivers/gpu/drm/panthor/panthor_pwr.c

0 → 100644
+121 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0 or MIT

/* Copyright 2025 ARM Limited. All rights reserved. */



#include <linux/platform_device.h>

#include <linux/interrupt.h>

#include <linux/iopoll.h>

#include <linux/wait.h>



#include <drm/drm_managed.h>

#include <drm/drm_print.h>



#include "panthor_device.h"

#include "panthor_hw.h"

#include "panthor_pwr.h"

#include "panthor_regs.h"



#define PWR_INTERRUPTS_MASK \

	(PWR_IRQ_POWER_CHANGED_SINGLE | \

	 PWR_IRQ_POWER_CHANGED_ALL | \

	 PWR_IRQ_DELEGATION_CHANGED | \

	 PWR_IRQ_RESET_COMPLETED | \

	 PWR_IRQ_RETRACT_COMPLETED | \

	 PWR_IRQ_INSPECT_COMPLETED | \

	 PWR_IRQ_COMMAND_NOT_ALLOWED | \

	 PWR_IRQ_COMMAND_INVALID)



/**

 * struct panthor_pwr - PWR_CONTROL block management data.

 */

struct panthor_pwr {

	/** @irq: PWR irq. */

	struct panthor_irq irq;



	/** @reqs_lock: Lock protecting access to pending_reqs. */

	spinlock_t reqs_lock;



	/** @pending_reqs: Pending PWR requests. */

	u32 pending_reqs;



	/** @reqs_acked: PWR request wait queue. */

	wait_queue_head_t reqs_acked;

};



static void panthor_pwr_irq_handler(struct panthor_device *ptdev, u32 status)

{

	spin_lock(&ptdev->pwr->reqs_lock);

	gpu_write(ptdev, PWR_INT_CLEAR, status);



	if (unlikely(status & PWR_IRQ_COMMAND_NOT_ALLOWED))

		drm_err(&ptdev->base, "PWR_IRQ: COMMAND_NOT_ALLOWED");



	if (unlikely(status & PWR_IRQ_COMMAND_INVALID))

		drm_err(&ptdev->base, "PWR_IRQ: COMMAND_INVALID");



	if (status & ptdev->pwr->pending_reqs) {

		ptdev->pwr->pending_reqs &= ~status;

		wake_up_all(&ptdev->pwr->reqs_acked);

	}

	spin_unlock(&ptdev->pwr->reqs_lock);

}

PANTHOR_IRQ_HANDLER(pwr, PWR, panthor_pwr_irq_handler);



void panthor_pwr_unplug(struct panthor_device *ptdev)

{

	unsigned long flags;



	if (!ptdev->pwr)

		return;



	/* Make sure the IRQ handler is not running after that point. */

	panthor_pwr_irq_suspend(&ptdev->pwr->irq);



	/* Wake-up all waiters. */

	spin_lock_irqsave(&ptdev->pwr->reqs_lock, flags);

	ptdev->pwr->pending_reqs = 0;

	wake_up_all(&ptdev->pwr->reqs_acked);

	spin_unlock_irqrestore(&ptdev->pwr->reqs_lock, flags);

}



int panthor_pwr_init(struct panthor_device *ptdev)

{

	struct panthor_pwr *pwr;

	int err, irq;



	if (!panthor_hw_has_pwr_ctrl(ptdev))

		return 0;



	pwr = drmm_kzalloc(&ptdev->base, sizeof(*pwr), GFP_KERNEL);

	if (!pwr)

		return -ENOMEM;



	spin_lock_init(&pwr->reqs_lock);

	init_waitqueue_head(&pwr->reqs_acked);

	ptdev->pwr = pwr;



	irq = platform_get_irq_byname(to_platform_device(ptdev->base.dev), "gpu");

	if (irq < 0)

		return irq;



	err = panthor_request_pwr_irq(ptdev, &pwr->irq, irq, PWR_INTERRUPTS_MASK);

	if (err)

		return err;



	return 0;

}



void panthor_pwr_suspend(struct panthor_device *ptdev)

{

	if (!ptdev->pwr)

		return;



	panthor_pwr_irq_suspend(&ptdev->pwr->irq);

}



void panthor_pwr_resume(struct panthor_device *ptdev)

{

	if (!ptdev->pwr)

		return;



	panthor_pwr_irq_resume(&ptdev->pwr->irq, PWR_INTERRUPTS_MASK);

}