linux-imx

/*

 * Copyright (C) 2017 Broadcom

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License as

 * published by the Free Software Foundation version 2.

 *

 * This program is distributed "as is" WITHOUT ANY WARRANTY of any

 * kind, whether express or implied; without even the implied warranty

 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

​

/*

 * Broadcom SBA RAID Driver

 *

 * The Broadcom stream buffer accelerator (SBA) provides offloading

 * capabilities for RAID operations. The SBA offload engine is accessible

 * via Broadcom SoC specific ring manager. Two or more offload engines

 * can share same Broadcom SoC specific ring manager due to this Broadcom

 * SoC specific ring manager driver is implemented as a mailbox controller

 * driver and offload engine drivers are implemented as mallbox clients.

 *

 * Typically, Broadcom SoC specific ring manager will implement larger

 * number of hardware rings over one or more SBA hardware devices. By

 * design, the internal buffer size of SBA hardware device is limited

 * but all offload operations supported by SBA can be broken down into

 * multiple small size requests and executed parallely on multiple SBA

 * hardware devices for achieving high through-put.

 *

 * The Broadcom SBA RAID driver does not require any register programming

 * except submitting request to SBA hardware device via mailbox channels.

 * This driver implements a DMA device with one DMA channel using a single

 * mailbox channel provided by Broadcom SoC specific ring manager driver.

 * For having more SBA DMA channels, we can create more SBA device nodes

 * in Broadcom SoC specific DTS based on number of hardware rings supported

 * by Broadcom SoC ring manager.

 */

​

#include <linux/bitops.h>

#include <linux/debugfs.h>

#include <linux/dma-mapping.h>

#include <linux/dmaengine.h>

#include <linux/list.h>

#include <linux/mailbox_client.h>

#include <linux/mailbox/brcm-message.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/slab.h>

#include <linux/raid/pq.h>

​

#include "dmaengine.h"

​

/* ====== Driver macros and defines ===== */

​

#define SBA_TYPE_SHIFT                  48

#define SBA_TYPE_MASK                   GENMASK(1, 0)

#define SBA_TYPE_A                  0x0

#define SBA_TYPE_B                  0x2

#define SBA_TYPE_C                  0x3

#define SBA_USER_DEF_SHIFT              32

#define SBA_USER_DEF_MASK               GENMASK(15, 0)

#define SBA_R_MDATA_SHIFT               24