Commit ce0925e8 authored by Tomas Winkler's avatar Tomas Winkler Committed by Greg Kroah-Hartman
Browse files

mei: dma ring buffers allocation 



Allocate DMA ring buffers from managed coherent memory.

Signed-off-by: default avatarTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: default avatarAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 986fb2e0

drivers/misc/mei/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ mei-objs += hbm.o 
mei-objs += interrupt.o

mei-objs += client.o

mei-objs += main.o

mei-objs += dma-ring.o

mei-objs += bus.o

mei-objs += bus-fixup.o

mei-$(CONFIG_DEBUG_FS) += debugfs.o

drivers/misc/mei/dma-ring.c

0 → 100644
+99 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright(c) 2016 - 2018 Intel Corporation. All rights reserved.

 */

#include <linux/dma-mapping.h>

#include <linux/mei.h>



#include "mei_dev.h"



/**

 * mei_dmam_dscr_alloc() - allocate a managed coherent buffer

 *     for the dma descriptor

 * @dev: mei_device

 * @dscr: dma descriptor

 *

 * Return:

 * * 0       - on success or zero allocation request

 * * -EINVAL - if size is not power of 2

 * * -ENOMEM - of allocation has failed

 */

static int mei_dmam_dscr_alloc(struct mei_device *dev,

			       struct mei_dma_dscr *dscr)

{

	if (!dscr->size)

		return 0;



	if (WARN_ON(!is_power_of_2(dscr->size)))

		return -EINVAL;



	if (dscr->vaddr)

		return 0;



	dscr->vaddr = dmam_alloc_coherent(dev->dev, dscr->size, &dscr->daddr,

					  GFP_KERNEL);

	if (!dscr->vaddr)

		return -ENOMEM;



	return 0;

}



/**

 * mei_dmam_dscr_free() - free a managed coherent buffer

 *     from the dma descriptor

 * @dev: mei_device

 * @dscr: dma descriptor

 */

static void mei_dmam_dscr_free(struct mei_device *dev,

			       struct mei_dma_dscr *dscr)

{

	if (!dscr->vaddr)

		return;



	dmam_free_coherent(dev->dev, dscr->size, dscr->vaddr, dscr->daddr);

	dscr->vaddr = NULL;

}



/**

 * mei_dmam_ring_free() - free dma ring buffers

 * @dev: mei device

 */

void mei_dmam_ring_free(struct mei_device *dev)

{

	int i;



	for (i = 0; i < DMA_DSCR_NUM; i++)

		mei_dmam_dscr_free(dev, &dev->dr_dscr[i]);

}



/**

 * mei_dmam_ring_alloc() - allocate dma ring buffers

 * @dev: mei device

 *

 * Return: -ENOMEM on allocation failure 0 otherwise

 */

int mei_dmam_ring_alloc(struct mei_device *dev)

{

	int i;



	for (i = 0; i < DMA_DSCR_NUM; i++)

		if (mei_dmam_dscr_alloc(dev, &dev->dr_dscr[i]))

			goto err;



	return 0;



err:

	mei_dmam_ring_free(dev);

	return -ENOMEM;

}



/**

 * mei_dma_ring_is_allocated() - check if dma ring is allocated

 * @dev: mei device

 *

 * Return: true if dma ring is allocated

 */

bool mei_dma_ring_is_allocated(struct mei_device *dev)

{

	return !!dev->dr_dscr[DMA_DSCR_HOST].vaddr;

}

drivers/misc/mei/hw-me.c

+6 −0
Original line number Diff line number Diff line
@@ -1471,15 +1471,21 @@ struct mei_device *mei_me_dev_init(struct pci_dev *pdev, 
{

	struct mei_device *dev;

	struct mei_me_hw *hw;

	int i;



	dev = devm_kzalloc(&pdev->dev, sizeof(struct mei_device) +

			   sizeof(struct mei_me_hw), GFP_KERNEL);

	if (!dev)

		return NULL;



	hw = to_me_hw(dev);



	for (i = 0; i < DMA_DSCR_NUM; i++)

		dev->dr_dscr[i].size = cfg->dma_size[i];



	mei_device_init(dev, &pdev->dev, &mei_me_hw_ops);

	hw->cfg = cfg;



	return dev;

}

drivers/misc/mei/mei_dev.h

+20 −0
Original line number Diff line number Diff line
@@ -122,6 +122,19 @@ struct mei_msg_data { 
	unsigned char *data;

};



/**

 * struct mei_dma_dscr - dma address descriptor

 *

 * @vaddr: dma buffer virtual address

 * @daddr: dma buffer physical address

 * @size : dma buffer size

 */

struct mei_dma_dscr {

	void *vaddr;

	dma_addr_t daddr;

	size_t size;

};



/* Maximum number of processed FW status registers */

#define MEI_FW_STATUS_MAX 6

/* Minimal  buffer for FW status string (8 bytes in dw + space or '\0') */
@@ -409,6 +422,7 @@ struct mei_fw_version { 
 * @rd_msg_hdr  : read message header storage

 *

 * @hbuf_is_ready : query if the host host/write buffer is ready

 * @dr_dscr: DMA ring descriptors: TX, RX, and CTRL

 *

 * @version     : HBM protocol version in use

 * @hbm_f_pg_supported  : hbm feature pgi protocol
@@ -488,6 +502,8 @@ struct mei_device { 
	/* write buffer */

	bool hbuf_is_ready;



	struct mei_dma_dscr dr_dscr[DMA_DSCR_NUM];



	struct hbm_version version;

	unsigned int hbm_f_pg_supported:1;

	unsigned int hbm_f_dc_supported:1;
@@ -578,6 +594,10 @@ int mei_restart(struct mei_device *dev); 
void mei_stop(struct mei_device *dev);

void mei_cancel_work(struct mei_device *dev);



int mei_dmam_ring_alloc(struct mei_device *dev);

void mei_dmam_ring_free(struct mei_device *dev);

bool mei_dma_ring_is_allocated(struct mei_device *dev);



/*

 *  MEI interrupt functions prototype

 */