coreboot-libre-fam15h-rdimm/3rdparty/arm-trusted-firmware/drivers/allwinner/sunxi_rsb.c

139 lines
3.2 KiB
C

/*
* Copyright (c) 2017-2018 ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <errno.h>
#include <common/debug.h>
#include <drivers/delay_timer.h>
#include <lib/mmio.h>
#include <sunxi_mmap.h>
#define RSB_CTRL 0x00
#define RSB_CCR 0x04
#define RSB_INTE 0x08
#define RSB_STAT 0x0c
#define RSB_DADDR0 0x10
#define RSB_DLEN 0x18
#define RSB_DATA0 0x1c
#define RSB_LCR 0x24
#define RSB_PMCR 0x28
#define RSB_CMD 0x2c
#define RSB_SADDR 0x30
#define RSBCMD_SRTA 0xE8
#define RSBCMD_RD8 0x8B
#define RSBCMD_RD16 0x9C
#define RSBCMD_RD32 0xA6
#define RSBCMD_WR8 0x4E
#define RSBCMD_WR16 0x59
#define RSBCMD_WR32 0x63
#define MAX_TRIES 100000
static int rsb_wait_bit(const char *desc, unsigned int offset, uint32_t mask)
{
uint32_t reg, tries = MAX_TRIES;
do
reg = mmio_read_32(SUNXI_R_RSB_BASE + offset);
while ((reg & mask) && --tries); /* transaction in progress */
if (reg & mask) {
ERROR("%s: timed out\n", desc);
return -ETIMEDOUT;
}
return 0;
}
static int rsb_wait_stat(const char *desc)
{
uint32_t reg;
int ret = rsb_wait_bit(desc, RSB_CTRL, BIT(7));
if (ret)
return ret;
reg = mmio_read_32(SUNXI_R_RSB_BASE + RSB_STAT);
if (reg == 0x01)
return 0;
ERROR("%s: 0x%x\n", desc, reg);
return -reg;
}
/* Initialize the RSB controller. */
int rsb_init_controller(void)
{
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CTRL, 0x01); /* soft reset */
return rsb_wait_bit("RSB: reset controller", RSB_CTRL, BIT(0));
}
int rsb_read(uint8_t rt_addr, uint8_t reg_addr)
{
int ret;
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CMD, RSBCMD_RD8); /* read a byte */
mmio_write_32(SUNXI_R_RSB_BASE + RSB_SADDR, rt_addr << 16);
mmio_write_32(SUNXI_R_RSB_BASE + RSB_DADDR0, reg_addr);
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CTRL, 0x80);/* start transaction */
ret = rsb_wait_stat("RSB: read command");
if (ret)
return ret;
return mmio_read_32(SUNXI_R_RSB_BASE + RSB_DATA0) & 0xff; /* result */
}
int rsb_write(uint8_t rt_addr, uint8_t reg_addr, uint8_t value)
{
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CMD, RSBCMD_WR8); /* byte write */
mmio_write_32(SUNXI_R_RSB_BASE + RSB_SADDR, rt_addr << 16);
mmio_write_32(SUNXI_R_RSB_BASE + RSB_DADDR0, reg_addr);
mmio_write_32(SUNXI_R_RSB_BASE + RSB_DATA0, value);
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CTRL, 0x80);/* start transaction */
return rsb_wait_stat("RSB: write command");
}
int rsb_set_device_mode(uint32_t device_mode)
{
mmio_write_32(SUNXI_R_RSB_BASE + RSB_PMCR,
(device_mode & 0x00ffffff) | BIT(31));
return rsb_wait_bit("RSB: set device to RSB", RSB_PMCR, BIT(31));
}
int rsb_set_bus_speed(uint32_t source_freq, uint32_t bus_freq)
{
uint32_t reg;
if (bus_freq == 0)
return -EINVAL;
reg = source_freq / bus_freq;
if (reg < 2)
return -EINVAL;
reg = reg / 2 - 1;
reg |= (1U << 8); /* one cycle of CD output delay */
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CCR, reg);
return 0;
}
/* Initialize the RSB PMIC connection. */
int rsb_assign_runtime_address(uint16_t hw_addr, uint8_t rt_addr)
{
mmio_write_32(SUNXI_R_RSB_BASE + RSB_SADDR, hw_addr | (rt_addr << 16));
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CMD, RSBCMD_SRTA);
mmio_write_32(SUNXI_R_RSB_BASE + RSB_CTRL, 0x80);
return rsb_wait_stat("RSB: set run-time address");
}