linux-imx

/*

 * Driver for the Octeon bootbus compact flash.

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 *

 * Copyright (C) 2005 - 2012 Cavium Inc.

 * Copyright (C) 2008 Wind River Systems

 */

​

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/libata.h>

#include <linux/hrtimer.h>

#include <linux/slab.h>

#include <linux/irq.h>

#include <linux/of.h>

#include <linux/of_platform.h>

#include <linux/platform_device.h>

#include <scsi/scsi_host.h>

​

#include <asm/byteorder.h>

#include <asm/octeon/octeon.h>

​

/*

 * The Octeon bootbus compact flash interface is connected in at least

 * 3 different configurations on various evaluation boards:

 *

 * -- 8  bits no irq, no DMA

 * -- 16 bits no irq, no DMA

 * -- 16 bits True IDE mode with DMA, but no irq.

 *

 * In the last case the DMA engine can generate an interrupt when the

 * transfer is complete.  For the first two cases only PIO is supported.

 *

 */

​

#define DRV_NAME    "pata_octeon_cf"

#define DRV_VERSION "2.2"

​

/* Poll interval in nS. */

#define OCTEON_CF_BUSY_POLL_INTERVAL 500000

​

#define DMA_CFG 0

#define DMA_TIM 0x20

#define DMA_INT 0x38

#define DMA_INT_EN 0x50

​

struct octeon_cf_port {

    struct hrtimer delayed_finish;

    struct ata_port *ap;

    int dma_finished;

    void        *c0;

    unsigned int cs0;

    unsigned int cs1;

    bool is_true_ide;

    u64 dma_base;

};

​

static struct scsi_host_template octeon_cf_sht = {

    ATA_PIO_SHT(DRV_NAME),

};

​

static int enable_dma;

module_param(enable_dma, int, 0444);

MODULE_PARM_DESC(enable_dma,

         "Enable use of DMA on interfaces that support it (0=no dma [default], 1=use dma)");

​

/**

 * Convert nanosecond based time to setting used in the

 * boot bus timing register, based on timing multiple

 */

static unsigned int ns_to_tim_reg(unsigned int tim_mult, unsigned int nsecs)

{

    unsigned int val;

​

    /*

     * Compute # of eclock periods to get desired duration in

     * nanoseconds.

     */

    val = DIV_ROUND_UP(nsecs * (octeon_get_io_clock_rate() / 1000000),

              1000 * tim_mult);

​

    return val;

}

​

static void octeon_cf_set_boot_reg_cfg(int cs, unsigned int multiplier)

{

    union cvmx_mio_boot_reg_cfgx reg_cfg;

    unsigned int tim_mult;

​