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

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/*
* 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 <spi.h>
#include <asm/io.h>
#include <asm/gpio.h>
#define SCLK (192 + 8) /* GPIO6 8 */
#define SSTBZ (64 + 3) /* GPIO2 3 */
#define MOSI (192 + 7) /* GPIO6 8 */
#define MISO (192 + 10) /* GPIO6 10 */
#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 */
static int cpld_initialized;
int spi_cs_is_valid(unsigned int bus, unsigned int cs)
{
/* Always valid */
return 1;
}
void spi_cs_activate(struct spi_slave *slave)
{
/* Always active */
}
void spi_cs_deactivate(struct spi_slave *slave)
{
/* Always active */
}
void ulcb_softspi_sda(int set)
{
gpio_set_value(MOSI, set);
}
void ulcb_softspi_scl(int set)
{
gpio_set_value(SCLK, set);
}
unsigned char ulcb_softspi_read(void)
{
return !!gpio_get_value(MISO);
}
static void cpld_rw(u8 write)
{
gpio_set_value(MOSI, write);
gpio_set_value(SSTBZ, 0);
gpio_set_value(SCLK, 1);
gpio_set_value(SCLK, 0);
gpio_set_value(SSTBZ, 1);
}
static u32 cpld_read(u8 addr)
{
u32 data = 0;
spi_xfer(NULL, 8, &addr, NULL, SPI_XFER_BEGIN | SPI_XFER_END);
cpld_rw(0);
spi_xfer(NULL, 32, NULL, &data, SPI_XFER_BEGIN | SPI_XFER_END);
return swab32(data);
}
static void cpld_write(u8 addr, u32 data)
{
data = swab32(data);
spi_xfer(NULL, 32, &data, NULL, SPI_XFER_BEGIN | SPI_XFER_END);
spi_xfer(NULL, 8, NULL, &addr, SPI_XFER_BEGIN | SPI_XFER_END);
cpld_rw(1);
}
static void cpld_init(void)
{
if (cpld_initialized)
return;
/* PULL-UP on MISO line */
setbits_le32(PFC_PUEN5, PUEN_SSI_SDATA4);
gpio_request(SCLK, NULL);
gpio_request(SSTBZ, NULL);
gpio_request(MOSI, NULL);
gpio_request(MISO, NULL);
gpio_direction_output(SCLK, 0);
gpio_direction_output(SSTBZ, 1);
gpio_direction_output(MOSI, 0);
gpio_direction_input(MISO);
/* Dummy read */
cpld_read(CPLD_ADDR_VERSION);
cpld_initialized = 1;
}
static int do_cpld(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
u32 addr, val;
cpld_init();
if (argc == 2 && strcmp(argv[1], "info") == 0) {
printf("CPLD version:\t\t\t0x%08x\n",
cpld_read(CPLD_ADDR_VERSION));
printf("H3 Mode setting (MD0..28):\t0x%08x\n",
cpld_read(CPLD_ADDR_MODE));
printf("Multiplexer settings:\t\t0x%08x\n",
cpld_read(CPLD_ADDR_MUX));
printf("DIPSW (SW6):\t\t\t0x%08x\n",
cpld_read(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(addr));
} else if (argc == 4 && strcmp(argv[1], "write") == 0) {
val = simple_strtoul(argv[3], NULL, 16);
cpld_write(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"
);
void reset_cpu(ulong addr)
{
cpld_init();
cpld_write(CPLD_ADDR_RESET, 1);
}