mtip32xx.c

/*
 * Driver for the Micron P320 SSD
 *   Copyright (C) 2011 Micron Technology, Inc.
 *
 * Portions of this code were derived from works subjected to the
 * following copyright:
 *    Copyright (C) 2009 Integrated Device Technology, Inc.
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/ata.h>
#include <linux/delay.h>
#include <linux/hdreg.h>
#include <linux/uaccess.h>
#include <linux/random.h>
#include <linux/smp.h>
#include <linux/compat.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/genhd.h>
#include <linux/blkdev.h>
#include <linux/bio.h>
#include <linux/dma-mapping.h>
#include <linux/idr.h>
#include <linux/kthread.h>
#include <../drivers/ata/ahci.h>
#include <linux/export.h>
#include <linux/debugfs.h>
#include "mtip32xx.h"

#define HW_CMD_SLOT_SZ		(MTIP_MAX_COMMAND_SLOTS * 32)
#define HW_CMD_TBL_SZ		(AHCI_CMD_TBL_HDR_SZ + (MTIP_MAX_SG * 16))
#define HW_CMD_TBL_AR_SZ	(HW_CMD_TBL_SZ * MTIP_MAX_COMMAND_SLOTS)
#define HW_PORT_PRIV_DMA_SZ \
		(HW_CMD_SLOT_SZ + HW_CMD_TBL_AR_SZ + AHCI_RX_FIS_SZ)

#define HOST_CAP_NZDMA		(1 << 19)
#define HOST_HSORG		0xFC
#define HSORG_DISABLE_SLOTGRP_INTR (1<<24)
#define HSORG_DISABLE_SLOTGRP_PXIS (1<<16)
#define HSORG_HWREV		0xFF00
#define HSORG_STYLE		0x8
#define HSORG_SLOTGROUPS	0x7

#define PORT_COMMAND_ISSUE	0x38
#define PORT_SDBV		0x7C

#define PORT_OFFSET		0x100
#define PORT_MEM_SIZE		0x80

#define PORT_IRQ_ERR \
	(PORT_IRQ_HBUS_ERR | PORT_IRQ_IF_ERR | PORT_IRQ_CONNECT | \
	 PORT_IRQ_PHYRDY | PORT_IRQ_UNK_FIS | PORT_IRQ_BAD_PMP | \
	 PORT_IRQ_TF_ERR | PORT_IRQ_HBUS_DATA_ERR | PORT_IRQ_IF_NONFATAL | \
	 PORT_IRQ_OVERFLOW)
#define PORT_IRQ_LEGACY \
	(PORT_IRQ_PIOS_FIS | PORT_IRQ_D2H_REG_FIS)
#define PORT_IRQ_HANDLED \
	(PORT_IRQ_SDB_FIS | PORT_IRQ_LEGACY | \
	 PORT_IRQ_TF_ERR | PORT_IRQ_IF_ERR | \
	 PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)
#define DEF_PORT_IRQ \
	(PORT_IRQ_ERR | PORT_IRQ_LEGACY | PORT_IRQ_SDB_FIS)

/* product numbers */
#define MTIP_PRODUCT_UNKNOWN	0x00
#define MTIP_PRODUCT_ASICFPGA	0x11

/* Device instance number, incremented each time a device is probed. */
static int instance;

/*
 * Global variable used to hold the major block device number
 * allocated in mtip_init().
 */
static int mtip_major;
static struct dentry *dfs_parent;

static DEFINE_SPINLOCK(rssd_index_lock);
static DEFINE_IDA(rssd_index_ida);

static int mtip_block_initialize(struct driver_data *dd);

#ifdef CONFIG_COMPAT
struct mtip_compat_ide_task_request_s {
	__u8		io_ports[8];
	__u8		hob_ports[8];
	ide_reg_valid_t	out_flags;
	ide_reg_valid_t	in_flags;
	int		data_phase;
	int		req_cmd;
	compat_ulong_t	out_size;
	compat_ulong_t	in_size;
};
#endif

/*
 * This function check_for_surprise_removal is called
 * while card is removed from the system and it will
 * read the vendor id from the configration space
 *
 * @pdev Pointer to the pci_dev structure.
 *
 * return value
 *	 true if device removed, else false
 */
static bool mtip_check_surprise_removal(struct pci_dev *pdev)
{
	u16 vendor_id = 0;

       /* Read the vendorID from the configuration space */
	pci_read_config_word(pdev, 0x00, &vendor_id);
	if (vendor_id == 0xFFFF)
		return true; /* device removed */

	return false; /* device present */
}

/*
 * This function is called for clean the pending command in the
 * command slot during the surprise removal of device and return
 * error to the upper layer.
 *
 * @dd Pointer to the DRIVER_DATA structure.
 *
 * return value
 *	None
 */
static void mtip_command_cleanup(struct driver_data *dd)
{
	int group = 0, commandslot = 0, commandindex = 0;
	struct mtip_cmd *command;
	struct mtip_port *port = dd->port;
	static int in_progress;

	if (in_progress)
		return;

	in_progress = 1;

	for (group = 0; group < 4; group++) {
		for (commandslot = 0; commandslot < 32; commandslot++) {
			if (!(port->allocated[group] & (1 << commandslot)))
				continue;

			commandindex = group << 5 | commandslot;
			command = &port->commands[commandindex];

			if (atomic_read(&command->active)
			    && (command->async_callback)) {
				command->async_callback(command->async_data,
					-ENODEV);
				command->async_callback = NULL;
				command->async_data = NULL;
			}

			dma_unmap_sg(&port->dd->pdev->dev,
				command->sg,
				command->scatter_ents,
				command->direction);
		}
	}

	up(&port->cmd_slot);

	set_bit(MTIP_DDF_CLEANUP_BIT, &dd->dd_flag);
	in_progress = 0;
}

/*
 * Obtain an empty command slot.
 *
 * This function needs to be reentrant since it could be called
 * at the same time on multiple CPUs. The allocation of the
 * command slot must be atomic.
 *
 * @port Pointer to the port data structure.
 *
 * return value
 *	>= 0	Index of command slot obtained.
 *	-1	No command slots available.
 */
static int get_slot(struct mtip_port *port)
{
	int slot, i;
	unsigned int num_command_slots = port->dd->slot_groups * 32;

	/*