drivers/gpu/drm/amd/amdkfd/kfd_kernel_queue.c - linux - Git at Google

 /*
  * Copyright 2014 Advanced Micro Devices, Inc.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  * OTHER DEALINGS IN THE SOFTWARE.
  *
  */

 #include <linux/types.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/printk.h>
 #include <linux/sched.h>
 #include "kfd_kernel_queue.h"
 #include "kfd_priv.h"
 #include "kfd_device_queue_manager.h"
 #include "kfd_pm4_headers.h"
 #include "kfd_pm4_opcodes.h"

 #define PM4_COUNT_ZERO (((1 << 15) - 1) << 16)

 static bool initialize(struct kernel_queue *kq, struct kfd_dev *dev,
 		enum kfd_queue_type type, unsigned int queue_size)
 {
 	struct queue_properties prop;
 	int retval;
 	union PM4_MES_TYPE_3_HEADER nop;

 	BUG_ON(!kq || !dev);
 	BUG_ON(type != KFD_QUEUE_TYPE_DIQ && type != KFD_QUEUE_TYPE_HIQ);

 	pr_debug("kfd: In func %s initializing queue type %d size %d\n",
 			__func__, KFD_QUEUE_TYPE_HIQ, queue_size);

 	nop.opcode = IT_NOP;
 	nop.type = PM4_TYPE_3;
 	nop.u32all |= PM4_COUNT_ZERO;

 	kq->dev = dev;
 	kq->nop_packet = nop.u32all;
 	switch (type) {
 	case KFD_QUEUE_TYPE_DIQ:
 	case KFD_QUEUE_TYPE_HIQ:
 		kq->mqd = dev->dqm->ops.get_mqd_manager(dev->dqm,
 						KFD_MQD_TYPE_HIQ);
 		break;
 	default:
 		BUG();
 		break;
 	}

 	if (kq->mqd == NULL)
 		return false;

 	prop.doorbell_ptr = kfd_get_kernel_doorbell(dev, &prop.doorbell_off);

 	if (prop.doorbell_ptr == NULL)
 		goto err_get_kernel_doorbell;

 	retval = kfd_gtt_sa_allocate(dev, queue_size, &kq->pq);
 	if (retval != 0)
 		goto err_pq_allocate_vidmem;

 	kq->pq_kernel_addr = kq->pq->cpu_ptr;
 	kq->pq_gpu_addr = kq->pq->gpu_addr;

 	retval = kq->ops_asic_specific.initialize(kq, dev, type, queue_size);
 	if (retval == false)
 		goto err_eop_allocate_vidmem;

 	retval = kfd_gtt_sa_allocate(dev, sizeof(*kq->rptr_kernel),
 					&kq->rptr_mem);

 	if (retval != 0)
 		goto err_rptr_allocate_vidmem;

 	kq->rptr_kernel = kq->rptr_mem->cpu_ptr;
 	kq->rptr_gpu_addr = kq->rptr_mem->gpu_addr;

 	retval = kfd_gtt_sa_allocate(dev, sizeof(*kq->wptr_kernel),
 					&kq->wptr_mem);

 	if (retval != 0)
 		goto err_wptr_allocate_vidmem;

 	kq->wptr_kernel = kq->wptr_mem->cpu_ptr;
 	kq->wptr_gpu_addr = kq->wptr_mem->gpu_addr;

 	memset(kq->pq_kernel_addr, 0, queue_size);
 	memset(kq->rptr_kernel, 0, sizeof(*kq->rptr_kernel));
 	memset(kq->wptr_kernel, 0, sizeof(*kq->wptr_kernel));

 	prop.queue_size = queue_size;
 	prop.is_interop = false;
 	prop.priority = 1;
 	prop.queue_percent = 100;
 	prop.type = type;
 	prop.vmid = 0;
 	prop.queue_address = kq->pq_gpu_addr;
 	prop.read_ptr = (uint32_t *) kq->rptr_gpu_addr;
 	prop.write_ptr = (uint32_t *) kq->wptr_gpu_addr;
 	prop.eop_ring_buffer_address = kq->eop_gpu_addr;
 	prop.eop_ring_buffer_size = PAGE_SIZE;

 	if (init_queue(&kq->queue, prop) != 0)
 		goto err_init_queue;

 	kq->queue->device = dev;
 	kq->queue->process = kfd_get_process(current);

 	retval = kq->mqd->init_mqd(kq->mqd, &kq->queue->mqd,
 					&kq->queue->mqd_mem_obj,
 					&kq->queue->gart_mqd_addr,
 					&kq->queue->properties);
 	if (retval != 0)
 		goto err_init_mqd;

 	/* assign HIQ to HQD */
 	if (type == KFD_QUEUE_TYPE_HIQ) {
 		pr_debug("assigning hiq to hqd\n");
 		kq->queue->pipe = KFD_CIK_HIQ_PIPE;
 		kq->queue->queue = KFD_CIK_HIQ_QUEUE;
 		kq->mqd->load_mqd(kq->mqd, kq->queue->mqd, kq->queue->pipe,
 					kq->queue->queue, NULL);
 	} else {
 		/* allocate fence for DIQ */

 		retval = kfd_gtt_sa_allocate(dev, sizeof(uint32_t),
 						&kq->fence_mem_obj);

 		if (retval != 0)
 			goto err_alloc_fence;

 		kq->fence_kernel_address = kq->fence_mem_obj->cpu_ptr;
 		kq->fence_gpu_addr = kq->fence_mem_obj->gpu_addr;
 	}

 	print_queue(kq->queue);

 	return true;
 err_alloc_fence:
 err_init_mqd:
 	uninit_queue(kq->queue);
 err_init_queue:
 	kfd_gtt_sa_free(dev, kq->wptr_mem);
 err_wptr_allocate_vidmem:
 	kfd_gtt_sa_free(dev, kq->rptr_mem);
 err_rptr_allocate_vidmem:
 	kfd_gtt_sa_free(dev, kq->eop_mem);
 err_eop_allocate_vidmem:
 	kfd_gtt_sa_free(dev, kq->pq);
 err_pq_allocate_vidmem:
 	pr_err("kfd: error init pq\n");
 	kfd_release_kernel_doorbell(dev, prop.doorbell_ptr);
 err_get_kernel_doorbell:
 	pr_err("kfd: error init doorbell");
 	return false;

 }

 static void uninitialize(struct kernel_queue *kq)
 {
 	BUG_ON(!kq);

 	if (kq->queue->properties.type == KFD_QUEUE_TYPE_HIQ)
 		kq->mqd->destroy_mqd(kq->mqd,
 					NULL,
 					false,
 					QUEUE_PREEMPT_DEFAULT_TIMEOUT_MS,
 					kq->queue->pipe,
 					kq->queue->queue);
 	else if (kq->queue->properties.type == KFD_QUEUE_TYPE_DIQ)
 		kfd_gtt_sa_free(kq->dev, kq->fence_mem_obj);

 	kfd_gtt_sa_free(kq->dev, kq->rptr_mem);
 	kfd_gtt_sa_free(kq->dev, kq->wptr_mem);
 	kq->ops_asic_specific.uninitialize(kq);
 	kfd_gtt_sa_free(kq->dev, kq->pq);
 	kfd_release_kernel_doorbell(kq->dev,
 					kq->queue->properties.doorbell_ptr);
 	uninit_queue(kq->queue);
 }

 static int acquire_packet_buffer(struct kernel_queue *kq,
 		size_t packet_size_in_dwords, unsigned int **buffer_ptr)
 {
 	size_t available_size;
 	size_t queue_size_dwords;
 	uint32_t wptr, rptr;
 	unsigned int *queue_address;

 	BUG_ON(!kq || !buffer_ptr);

 	rptr = *kq->rptr_kernel;
 	wptr = *kq->wptr_kernel;
 	queue_address = (unsigned int *)kq->pq_kernel_addr;
 	queue_size_dwords = kq->queue->properties.queue_size / sizeof(uint32_t);

 	pr_debug("kfd: In func %s\nrptr: %d\nwptr: %d\nqueue_address 0x%p\n",
 			__func__, rptr, wptr, queue_address);

 	available_size = (rptr - 1 - wptr + queue_size_dwords) %
 							queue_size_dwords;

 	if (packet_size_in_dwords >= queue_size_dwords ||
 			packet_size_in_dwords >= available_size) {
 		/*
 		 * make sure calling functions know
 		 * acquire_packet_buffer() failed
 		 */
 		*buffer_ptr = NULL;
 		return -ENOMEM;
 	}

 	if (wptr + packet_size_in_dwords >= queue_size_dwords) {
 		while (wptr > 0) {
 			queue_address[wptr] = kq->nop_packet;
 			wptr = (wptr + 1) % queue_size_dwords;
 		}
 	}

 	*buffer_ptr = &queue_address[wptr];
 	kq->pending_wptr = wptr + packet_size_in_dwords;

 	return 0;
 }

 static void submit_packet(struct kernel_queue *kq)
 {
 #ifdef DEBUG
 	int i;
 #endif

 	BUG_ON(!kq);

 #ifdef DEBUG
 	for (i = *kq->wptr_kernel; i < kq->pending_wptr; i++) {
 		pr_debug("0x%2X ", kq->pq_kernel_addr[i]);
 		if (i % 15 == 0)
 			pr_debug("\n");
 	}
 	pr_debug("\n");
 #endif

 	*kq->wptr_kernel = kq->pending_wptr;
 	write_kernel_doorbell(kq->queue->properties.doorbell_ptr,
 				kq->pending_wptr);
 }

 static void rollback_packet(struct kernel_queue *kq)
 {
 	BUG_ON(!kq);
 	kq->pending_wptr = *kq->queue->properties.write_ptr;
 }

 struct kernel_queue *kernel_queue_init(struct kfd_dev *dev,
 					enum kfd_queue_type type)
 {
 	struct kernel_queue *kq;

 	BUG_ON(!dev);

 	kq = kzalloc(sizeof(struct kernel_queue), GFP_KERNEL);
 	if (!kq)
 		return NULL;

 	kq->ops.initialize = initialize;
 	kq->ops.uninitialize = uninitialize;
 	kq->ops.acquire_packet_buffer = acquire_packet_buffer;
 	kq->ops.submit_packet = submit_packet;
 	kq->ops.rollback_packet = rollback_packet;

 	switch (dev->device_info->asic_family) {
 	case CHIP_CARRIZO:
 		kernel_queue_init_vi(&kq->ops_asic_specific);
 		break;

 	case CHIP_KAVERI:
 		kernel_queue_init_cik(&kq->ops_asic_specific);
 		break;
 	}

 	if (kq->ops.initialize(kq, dev, type, KFD_KERNEL_QUEUE_SIZE) == false) {
 		pr_err("kfd: failed to init kernel queue\n");
 		kfree(kq);
 		return NULL;
 	}
 	return kq;
 }

 void kernel_queue_uninit(struct kernel_queue *kq)
 {
 	BUG_ON(!kq);

 	kq->ops.uninitialize(kq);
 	kfree(kq);
 }

 static __attribute__((unused)) void test_kq(struct kfd_dev *dev)
 {
 	struct kernel_queue *kq;
 	uint32_t *buffer, i;
 	int retval;

 	BUG_ON(!dev);

 	pr_err("kfd: starting kernel queue test\n");

 	kq = kernel_queue_init(dev, KFD_QUEUE_TYPE_HIQ);
 	BUG_ON(!kq);

 	retval = kq->ops.acquire_packet_buffer(kq, 5, &buffer);
 	BUG_ON(retval != 0);
 	for (i = 0; i < 5; i++)
 		buffer[i] = kq->nop_packet;
 	kq->ops.submit_packet(kq);

 	pr_err("kfd: ending kernel queue test\n");
 }
	/*
	* Copyright 2014 Advanced Micro Devices, Inc.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
	* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
	* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
	* OTHER DEALINGS IN THE SOFTWARE.
	*
	*/

	#include <linux/types.h>
	#include <linux/mutex.h>
	#include <linux/slab.h>
	#include <linux/printk.h>
	#include <linux/sched.h>
	#include "kfd_kernel_queue.h"
	#include "kfd_priv.h"
	#include "kfd_device_queue_manager.h"
	#include "kfd_pm4_headers.h"
	#include "kfd_pm4_opcodes.h"

	#define PM4_COUNT_ZERO (((1 << 15) - 1) << 16)

	static bool initialize(struct kernel_queue kq, struct kfd_dev dev,
	enum kfd_queue_type type, unsigned int queue_size)
	{
	struct queue_properties prop;
	int retval;
	union PM4_MES_TYPE_3_HEADER nop;

	BUG_ON(!kq \|\| !dev);
	BUG_ON(type != KFD_QUEUE_TYPE_DIQ && type != KFD_QUEUE_TYPE_HIQ);

	pr_debug("kfd: In func %s initializing queue type %d size %d\n",
	__func__, KFD_QUEUE_TYPE_HIQ, queue_size);

	nop.opcode = IT_NOP;
	nop.type = PM4_TYPE_3;
	nop.u32all \|= PM4_COUNT_ZERO;

	kq->dev = dev;
	kq->nop_packet = nop.u32all;
	switch (type) {
	case KFD_QUEUE_TYPE_DIQ:
	case KFD_QUEUE_TYPE_HIQ:
	kq->mqd = dev->dqm->ops.get_mqd_manager(dev->dqm,
	KFD_MQD_TYPE_HIQ);
	break;
	default:
	BUG();
	break;
	}

	if (kq->mqd == NULL)
	return false;

	prop.doorbell_ptr = kfd_get_kernel_doorbell(dev, &prop.doorbell_off);

	if (prop.doorbell_ptr == NULL)
	goto err_get_kernel_doorbell;

	retval = kfd_gtt_sa_allocate(dev, queue_size, &kq->pq);
	if (retval != 0)
	goto err_pq_allocate_vidmem;

	kq->pq_kernel_addr = kq->pq->cpu_ptr;
	kq->pq_gpu_addr = kq->pq->gpu_addr;

	retval = kq->ops_asic_specific.initialize(kq, dev, type, queue_size);
	if (retval == false)
	goto err_eop_allocate_vidmem;

	retval = kfd_gtt_sa_allocate(dev, sizeof(*kq->rptr_kernel),
	&kq->rptr_mem);

	if (retval != 0)
	goto err_rptr_allocate_vidmem;

	kq->rptr_kernel = kq->rptr_mem->cpu_ptr;
	kq->rptr_gpu_addr = kq->rptr_mem->gpu_addr;

	retval = kfd_gtt_sa_allocate(dev, sizeof(*kq->wptr_kernel),
	&kq->wptr_mem);

	if (retval != 0)
	goto err_wptr_allocate_vidmem;

	kq->wptr_kernel = kq->wptr_mem->cpu_ptr;
	kq->wptr_gpu_addr = kq->wptr_mem->gpu_addr;

	memset(kq->pq_kernel_addr, 0, queue_size);
	memset(kq->rptr_kernel, 0, sizeof(*kq->rptr_kernel));
	memset(kq->wptr_kernel, 0, sizeof(*kq->wptr_kernel));

	prop.queue_size = queue_size;
	prop.is_interop = false;
	prop.priority = 1;
	prop.queue_percent = 100;
	prop.type = type;
	prop.vmid = 0;
	prop.queue_address = kq->pq_gpu_addr;
	prop.read_ptr = (uint32_t *) kq->rptr_gpu_addr;
	prop.write_ptr = (uint32_t *) kq->wptr_gpu_addr;
	prop.eop_ring_buffer_address = kq->eop_gpu_addr;
	prop.eop_ring_buffer_size = PAGE_SIZE;

	if (init_queue(&kq->queue, prop) != 0)
	goto err_init_queue;

	kq->queue->device = dev;
	kq->queue->process = kfd_get_process(current);

	retval = kq->mqd->init_mqd(kq->mqd, &kq->queue->mqd,
	&kq->queue->mqd_mem_obj,
	&kq->queue->gart_mqd_addr,
	&kq->queue->properties);
	if (retval != 0)
	goto err_init_mqd;

	/* assign HIQ to HQD */
	if (type == KFD_QUEUE_TYPE_HIQ) {
	pr_debug("assigning hiq to hqd\n");
	kq->queue->pipe = KFD_CIK_HIQ_PIPE;
	kq->queue->queue = KFD_CIK_HIQ_QUEUE;
	kq->mqd->load_mqd(kq->mqd, kq->queue->mqd, kq->queue->pipe,
	kq->queue->queue, NULL);
	} else {
	/* allocate fence for DIQ */

	retval = kfd_gtt_sa_allocate(dev, sizeof(uint32_t),
	&kq->fence_mem_obj);

	if (retval != 0)
	goto err_alloc_fence;

	kq->fence_kernel_address = kq->fence_mem_obj->cpu_ptr;
	kq->fence_gpu_addr = kq->fence_mem_obj->gpu_addr;
	}

	print_queue(kq->queue);

	return true;
	err_alloc_fence:
	err_init_mqd:
	uninit_queue(kq->queue);
	err_init_queue:
	kfd_gtt_sa_free(dev, kq->wptr_mem);
	err_wptr_allocate_vidmem:
	kfd_gtt_sa_free(dev, kq->rptr_mem);
	err_rptr_allocate_vidmem:
	kfd_gtt_sa_free(dev, kq->eop_mem);
	err_eop_allocate_vidmem:
	kfd_gtt_sa_free(dev, kq->pq);
	err_pq_allocate_vidmem:
	pr_err("kfd: error init pq\n");
	kfd_release_kernel_doorbell(dev, prop.doorbell_ptr);
	err_get_kernel_doorbell:
	pr_err("kfd: error init doorbell");
	return false;

	}

	static void uninitialize(struct kernel_queue *kq)
	{
	BUG_ON(!kq);

	if (kq->queue->properties.type == KFD_QUEUE_TYPE_HIQ)
	kq->mqd->destroy_mqd(kq->mqd,
	NULL,
	false,
	QUEUE_PREEMPT_DEFAULT_TIMEOUT_MS,
	kq->queue->pipe,
	kq->queue->queue);
	else if (kq->queue->properties.type == KFD_QUEUE_TYPE_DIQ)
	kfd_gtt_sa_free(kq->dev, kq->fence_mem_obj);

	kfd_gtt_sa_free(kq->dev, kq->rptr_mem);
	kfd_gtt_sa_free(kq->dev, kq->wptr_mem);
	kq->ops_asic_specific.uninitialize(kq);
	kfd_gtt_sa_free(kq->dev, kq->pq);
	kfd_release_kernel_doorbell(kq->dev,
	kq->queue->properties.doorbell_ptr);
	uninit_queue(kq->queue);
	}

	static int acquire_packet_buffer(struct kernel_queue *kq,
	size_t packet_size_in_dwords, unsigned int **buffer_ptr)
	{
	size_t available_size;
	size_t queue_size_dwords;
	uint32_t wptr, rptr;
	unsigned int *queue_address;

	BUG_ON(!kq \|\| !buffer_ptr);

	rptr = *kq->rptr_kernel;
	wptr = *kq->wptr_kernel;
	queue_address = (unsigned int *)kq->pq_kernel_addr;
	queue_size_dwords = kq->queue->properties.queue_size / sizeof(uint32_t);

	pr_debug("kfd: In func %s\nrptr: %d\nwptr: %d\nqueue_address 0x%p\n",
	__func__, rptr, wptr, queue_address);

	available_size = (rptr - 1 - wptr + queue_size_dwords) %
	queue_size_dwords;

	if (packet_size_in_dwords >= queue_size_dwords \|\|
	packet_size_in_dwords >= available_size) {
	/*
	* make sure calling functions know
	* acquire_packet_buffer() failed
	*/
	*buffer_ptr = NULL;
	return -ENOMEM;
	}

	if (wptr + packet_size_in_dwords >= queue_size_dwords) {
	while (wptr > 0) {
	queue_address[wptr] = kq->nop_packet;
	wptr = (wptr + 1) % queue_size_dwords;
	}
	}

	*buffer_ptr = &queue_address[wptr];
	kq->pending_wptr = wptr + packet_size_in_dwords;

	return 0;
	}

	static void submit_packet(struct kernel_queue *kq)
	{
	#ifdef DEBUG
	int i;
	#endif

	BUG_ON(!kq);

	#ifdef DEBUG
	for (i = *kq->wptr_kernel; i < kq->pending_wptr; i++) {
	pr_debug("0x%2X ", kq->pq_kernel_addr[i]);
	if (i % 15 == 0)
	pr_debug("\n");
	}
	pr_debug("\n");
	#endif

	*kq->wptr_kernel = kq->pending_wptr;
	write_kernel_doorbell(kq->queue->properties.doorbell_ptr,
	kq->pending_wptr);
	}

	static void rollback_packet(struct kernel_queue *kq)
	{
	BUG_ON(!kq);
	kq->pending_wptr = *kq->queue->properties.write_ptr;
	}

	struct kernel_queue kernel_queue_init(struct kfd_dev dev,
	enum kfd_queue_type type)
	{
	struct kernel_queue *kq;

	BUG_ON(!dev);

	kq = kzalloc(sizeof(struct kernel_queue), GFP_KERNEL);
	if (!kq)
	return NULL;

	kq->ops.initialize = initialize;
	kq->ops.uninitialize = uninitialize;
	kq->ops.acquire_packet_buffer = acquire_packet_buffer;
	kq->ops.submit_packet = submit_packet;
	kq->ops.rollback_packet = rollback_packet;

	switch (dev->device_info->asic_family) {
	case CHIP_CARRIZO:
	kernel_queue_init_vi(&kq->ops_asic_specific);
	break;

	case CHIP_KAVERI:
	kernel_queue_init_cik(&kq->ops_asic_specific);
	break;
	}

	if (kq->ops.initialize(kq, dev, type, KFD_KERNEL_QUEUE_SIZE) == false) {
	pr_err("kfd: failed to init kernel queue\n");
	kfree(kq);
	return NULL;
	}
	return kq;
	}

	void kernel_queue_uninit(struct kernel_queue *kq)
	{
	BUG_ON(!kq);

	kq->ops.uninitialize(kq);
	kfree(kq);
	}

	static __attribute__((unused)) void test_kq(struct kfd_dev *dev)
	{
	struct kernel_queue *kq;
	uint32_t *buffer, i;
	int retval;

	BUG_ON(!dev);

	pr_err("kfd: starting kernel queue test\n");

	kq = kernel_queue_init(dev, KFD_QUEUE_TYPE_HIQ);
	BUG_ON(!kq);

	retval = kq->ops.acquire_packet_buffer(kq, 5, &buffer);
	BUG_ON(retval != 0);
	for (i = 0; i < 5; i++)
	buffer[i] = kq->nop_packet;
	kq->ops.submit_packet(kq);

	pr_err("kfd: ending kernel queue test\n");
	}