linux-imx

/*

 * Altera Passive Serial SPI Driver

 *

 *  Copyright (c) 2017 United Western Technologies, Corporation

 *

 *  Joshua Clayton <stillcompiling@gmail.com>

 *

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

 * under the terms and conditions of the GNU General Public License,

 * version 2, as published by the Free Software Foundation.

 *

 * Manage Altera FPGA firmware that is loaded over SPI using the passive

 * serial configuration method.

 * Firmware must be in binary "rbf" format.

 * Works on Arria 10, Cyclone V and Stratix V. Should work on Cyclone series.

 * May work on other Altera FPGAs.

 */

​

#include <linux/bitrev.h>

#include <linux/delay.h>

#include <linux/fpga/fpga-mgr.h>

#include <linux/gpio/consumer.h>

#include <linux/module.h>

#include <linux/of_gpio.h>

#include <linux/of_device.h>

#include <linux/spi/spi.h>

#include <linux/sizes.h>

​

enum altera_ps_devtype {

    CYCLONE5,

    ARRIA10,

};

​

struct altera_ps_data {

    enum altera_ps_devtype devtype;

    int status_wait_min_us;

    int status_wait_max_us;

    int t_cfg_us;

    int t_st2ck_us;

};

​

struct altera_ps_conf {

    struct gpio_desc *config;

    struct gpio_desc *confd;

    struct gpio_desc *status;

    struct spi_device *spi;

    const struct altera_ps_data *data;

    u32 info_flags;

    char mgr_name[64];

};

​

/*          |   Arria 10  |   Cyclone5  |   Stratix5  |

 * t_CF2ST0 |     [; 600] |     [; 600] |     [; 600] |ns

 * t_CFG    |        [2;] |        [2;] |        [2;] |µs

 * t_STATUS | [268; 3000] | [268; 1506] | [268; 1506] |µs

 * t_CF2ST1 |    [; 3000] |    [; 1506] |    [; 1506] |µs

 * t_CF2CK  |     [3010;] |     [1506;] |     [1506;] |µs

 * t_ST2CK  |       [10;] |        [2;] |        [2;] |µs

 * t_CD2UM  |  [175; 830] |  [175; 437] |  [175; 437] |µs

 */

static struct altera_ps_data c5_data = {

    /* these values for Cyclone5 are compatible with Stratix5 */

    .devtype = CYCLONE5,

    .status_wait_min_us = 268,

    .status_wait_max_us = 1506,

    .t_cfg_us = 2,

    .t_st2ck_us = 2,

};

​

static struct altera_ps_data a10_data = {

    .devtype = ARRIA10,

    .status_wait_min_us = 268,  /* min(t_STATUS) */

    .status_wait_max_us = 3000, /* max(t_CF2ST1) */

    .t_cfg_us = 2,    /* max { min(t_CFG), max(tCF2ST0) } */

    .t_st2ck_us = 10, /* min(t_ST2CK) */

};

​

/* Array index is enum altera_ps_devtype */

static const struct altera_ps_data *altera_ps_data_map[] = {

    &c5_data,

    &a10_data,

};

​

static const struct of_device_id of_ef_match[] = {

    { .compatible = "altr,fpga-passive-serial", .data = &c5_data },

    { .compatible = "altr,fpga-arria10-passive-serial", .data = &a10_data },

    {}

};

MODULE_DEVICE_TABLE(of, of_ef_match);

​

static enum fpga_mgr_states altera_ps_state(struct fpga_manager *mgr)

{