u-boot/board/renesas/ulcb/cpld.c

192 lines
4.6 KiB
C
Raw Normal View History

/*
* ULCB board CPLD access support
*
* Copyright (C) 2017 Renesas Electronics Corporation
* Copyright (C) 2017 Cogent Embedded, Inc.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/gpio.h>
#include <asm/io.h>
#include <dm.h>
#include <errno.h>
#include <linux/err.h>
#include <sysreset.h>
#define CPLD_ADDR_MODE 0x00 /* RW */
#define CPLD_ADDR_MUX 0x02 /* RW */
#define CPLD_ADDR_DIPSW6 0x08 /* R */
#define CPLD_ADDR_RESET 0x80 /* RW */
#define CPLD_ADDR_VERSION 0xFF /* R */
struct renesas_ulcb_sysreset_priv {
struct gpio_desc miso;
struct gpio_desc mosi;
struct gpio_desc sck;
struct gpio_desc sstbz;
};
static u32 cpld_read(struct udevice *dev, u8 addr)
{
struct renesas_ulcb_sysreset_priv *priv = dev_get_priv(dev);
u32 data = 0;
int i;
for (i = 0; i < 8; i++) {
dm_gpio_set_value(&priv->mosi, !!(addr & 0x80)); /* MSB first */
dm_gpio_set_value(&priv->sck, 1);
addr <<= 1;
dm_gpio_set_value(&priv->sck, 0);
}
dm_gpio_set_value(&priv->mosi, 0); /* READ */
dm_gpio_set_value(&priv->sstbz, 0);
dm_gpio_set_value(&priv->sck, 1);
dm_gpio_set_value(&priv->sck, 0);
dm_gpio_set_value(&priv->sstbz, 1);
for (i = 0; i < 32; i++) {
dm_gpio_set_value(&priv->sck, 1);
data <<= 1;
data |= dm_gpio_get_value(&priv->miso); /* MSB first */
dm_gpio_set_value(&priv->sck, 0);
}
return data;
}
static void cpld_write(struct udevice *dev, u8 addr, u32 data)
{
struct renesas_ulcb_sysreset_priv *priv = dev_get_priv(dev);
int i;
for (i = 0; i < 32; i++) {
dm_gpio_set_value(&priv->mosi, data & (1 << 31)); /* MSB first */
dm_gpio_set_value(&priv->sck, 1);
data <<= 1;
dm_gpio_set_value(&priv->sck, 0);
}
for (i = 0; i < 8; i++) {
dm_gpio_set_value(&priv->mosi, addr & 0x80); /* MSB first */
dm_gpio_set_value(&priv->sck, 1);
addr <<= 1;
dm_gpio_set_value(&priv->sck, 0);
}
dm_gpio_set_value(&priv->mosi, 1); /* WRITE */
dm_gpio_set_value(&priv->sstbz, 0);
dm_gpio_set_value(&priv->sck, 1);
dm_gpio_set_value(&priv->sck, 0);
dm_gpio_set_value(&priv->sstbz, 1);
}
static int do_cpld(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
struct udevice *dev;
u32 addr, val;
int ret;
ret = uclass_get_device_by_driver(UCLASS_SYSRESET,
DM_GET_DRIVER(sysreset_renesas_ulcb),
&dev);
if (ret)
return ret;
if (argc == 2 && strcmp(argv[1], "info") == 0) {
printf("CPLD version:\t\t\t0x%08x\n",
cpld_read(dev, CPLD_ADDR_VERSION));
printf("H3 Mode setting (MD0..28):\t0x%08x\n",
cpld_read(dev, CPLD_ADDR_MODE));
printf("Multiplexer settings:\t\t0x%08x\n",
cpld_read(dev, CPLD_ADDR_MUX));
printf("DIPSW (SW6):\t\t\t0x%08x\n",
cpld_read(dev, CPLD_ADDR_DIPSW6));
return 0;
}
if (argc < 3)
return CMD_RET_USAGE;
addr = simple_strtoul(argv[2], NULL, 16);
if (!(addr == CPLD_ADDR_VERSION || addr == CPLD_ADDR_MODE ||
addr == CPLD_ADDR_MUX || addr == CPLD_ADDR_DIPSW6 ||
addr == CPLD_ADDR_RESET)) {
printf("Invalid CPLD register address\n");
return CMD_RET_USAGE;
}
if (argc == 3 && strcmp(argv[1], "read") == 0) {
printf("0x%x\n", cpld_read(dev, addr));
} else if (argc == 4 && strcmp(argv[1], "write") == 0) {
val = simple_strtoul(argv[3], NULL, 16);
cpld_write(dev, addr, val);
}
return 0;
}
U_BOOT_CMD(
cpld, 4, 1, do_cpld,
"CPLD access",
"info\n"
"cpld read addr\n"
"cpld write addr val\n"
);
static int renesas_ulcb_sysreset_request(struct udevice *dev, enum sysreset_t type)
{
cpld_write(dev, CPLD_ADDR_RESET, 1);
return -EINPROGRESS;
}
static int renesas_ulcb_sysreset_probe(struct udevice *dev)
{
struct renesas_ulcb_sysreset_priv *priv = dev_get_priv(dev);
if (gpio_request_by_name(dev, "gpio-miso", 0, &priv->miso,
GPIOD_IS_IN))
return -EINVAL;
if (gpio_request_by_name(dev, "gpio-sck", 0, &priv->sck,
GPIOD_IS_OUT))
return -EINVAL;
if (gpio_request_by_name(dev, "gpio-sstbz", 0, &priv->sstbz,
GPIOD_IS_OUT | GPIOD_IS_OUT_ACTIVE))
return -EINVAL;
if (gpio_request_by_name(dev, "gpio-mosi", 0, &priv->mosi,
GPIOD_IS_OUT))
return -EINVAL;
/* PULL-UP on MISO line */
setbits_le32(PFC_PUEN5, PUEN_SSI_SDATA4);
/* Dummy read */
cpld_read(dev, CPLD_ADDR_VERSION);
return 0;
}
static struct sysreset_ops renesas_ulcb_sysreset = {
.request = renesas_ulcb_sysreset_request,
};
static const struct udevice_id renesas_ulcb_sysreset_ids[] = {
{ .compatible = "renesas,ulcb-cpld" },
{ }
};
U_BOOT_DRIVER(sysreset_renesas_ulcb) = {
.name = "renesas_ulcb_sysreset",
.id = UCLASS_SYSRESET,
.ops = &renesas_ulcb_sysreset,
.probe = renesas_ulcb_sysreset_probe,
.of_match = renesas_ulcb_sysreset_ids,
.priv_auto_alloc_size = sizeof(struct renesas_ulcb_sysreset_priv),
};