blob: 46ac9cf174e0db7264980c211e013df27991174f [file] [log] [blame]
/*
* Copyright (c) 2021, STMicroelectronics - All Rights Reserved
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <assert.h>
#include <endian.h>
#include <errno.h>
#include <string.h>
#include <arch_helpers.h>
#include <common/debug.h>
#include <drivers/delay_timer.h>
#include <drivers/st/stm32_iwdg.h>
#include <drivers/st/stm32_uart.h>
#include <drivers/st/stm32_uart_regs.h>
#include <lib/mmio.h>
#include <tools_share/firmware_image_package.h>
#include <platform_def.h>
#include <stm32cubeprogrammer.h>
/* USART bootloader protocol version V4.0 */
#define USART_BL_VERSION 0x40U
/* Command definition */
#define GET_CMD_COMMAND 0x00U
#define GET_VER_COMMAND 0x01U
#define GET_ID_COMMAND 0x02U
#define PHASE_COMMAND 0x03U
#define READ_PART_COMMAND 0x12U
#define START_COMMAND 0x21U
#define DOWNLOAD_COMMAND 0x31U
/* Answer defines */
#define INIT_BYTE 0x7FU
#define ACK_BYTE 0x79U
#define NACK_BYTE 0x1FU
#define ABORT 0x5FU
#define UNDEFINED_DOWN_ADDR U(0xFFFFFFFF)
#define PROGRAMMER_TIMEOUT_US 20000U
static const uint8_t command_tab[] = {
GET_CMD_COMMAND,
GET_VER_COMMAND,
GET_ID_COMMAND,
PHASE_COMMAND,
START_COMMAND,
DOWNLOAD_COMMAND
};
/* STM32CubeProgrammer over UART handle */
struct stm32prog_uart_handle_s {
struct stm32_uart_handle_s uart;
uint32_t packet;
uint8_t *addr;
uint32_t len;
uint8_t phase;
/* Error msg buffer: max 255 in UART protocol, reduced in TF-A */
uint8_t error[64];
} handle;
/* Trace and handle unrecoverable UART protocol error */
#define STM32PROG_ERROR(...) \
{ \
ERROR(__VA_ARGS__); \
if (handle.phase != PHASE_RESET) { \
snprintf((char *)&handle.error, sizeof(handle.error), __VA_ARGS__); \
handle.phase = PHASE_RESET; \
handle.addr = (uint8_t *)UNDEFINED_DOWN_ADDR; \
handle.len = 0U; \
handle.packet = 0U; \
} \
}
static int uart_write(const uint8_t *addr, uint16_t size)
{
while (size != 0U) {
if (stm32_uart_putc(&handle.uart, *addr) != 0) {
return -EIO;
}
size--;
addr++;
}
return 0;
}
static int uart_write_8(uint8_t byte)
{
return stm32_uart_putc(&handle.uart, byte);
}
static int uart_write_32(uint32_t value)
{
return uart_write((uint8_t *)&value, 4U);
}
static int uart_read_8(uint8_t *byte)
{
int ret;
uint64_t timeout_ref = timeout_init_us(PROGRAMMER_TIMEOUT_US);
do {
ret = stm32_uart_getc(&handle.uart);
if (ret == -EAGAIN) {
if (timeout_elapsed(timeout_ref)) {
return -ETIMEDOUT;
}
} else if (ret < 0) {
return ret;
}
} while (ret == -EAGAIN);
*byte = (uint8_t)ret;
return 0;
}
static int uart_send_result(uint8_t byte)
{
int ret;
/* Always flush fifo before to send result = read all pending data */
do {
ret = stm32_uart_getc(&handle.uart);
} while (ret >= 0);
return uart_write_8(byte);
}
static bool is_valid_header(fip_toc_header_t *header)
{
return (header->name == TOC_HEADER_NAME) &&
(header->serial_number != 0U);
}
static int uart_receive_command(uint8_t *command)
{
uint8_t byte = 0U;
uint8_t xor = 0U;
unsigned int count;
bool found = false;
int ret;
/* Repeat read until something is received */
do {
stm32_iwdg_refresh();
ret = uart_read_8(&byte);
} while (ret == -ETIMEDOUT);
if (ret != 0) {
return ret;
}
/* Handle reconnection request */
if (byte == INIT_BYTE) {
*command = byte;
return 0;
}
for (count = 0U; count < ARRAY_SIZE(command_tab); count++) {
if (command_tab[count] == byte) {
found = true;
break;
}
}
if (!found) {
VERBOSE("UART: Command unknown (byte=0x%x)\n", byte);
return -EPROTO;
}
ret = uart_read_8(&xor);
if (ret != 0) {
return ret;
}
if ((byte ^ xor) != 0xFF) {
VERBOSE("UART: Command XOR check fail (byte=0x%x, xor=0x%x)\n",
byte, xor);
return -EPROTO;
}
*command = byte;
return 0;
}
static int get_cmd_command(void)
{
const uint8_t msg[2] = {
sizeof(command_tab), /* Length of data - 1 */
USART_BL_VERSION
};
int ret;
ret = uart_write(msg, sizeof(msg));
if (ret != 0) {
return ret;
}
return uart_write(command_tab, sizeof(command_tab));
}
static int get_version_command(void)
{
return uart_write_8(STM32_TF_VERSION);
}
static int get_id_command(void)
{
uint8_t msg[3] = {
sizeof(msg) - 1 /* Length of data - 1 */
};
uint32_t chip_id = stm32mp_get_chip_dev_id();
be16enc(&msg[1], chip_id);
return uart_write(msg, sizeof(msg));
}
static int uart_send_phase(uint32_t address)
{
int ret;
uint8_t msg_size = 5U; /* Length of data - 1 */
uint8_t error_size = 0U;
/* Additional information only for RESET phase */
if (handle.phase == PHASE_RESET) {
error_size = strnlen((char *)&handle.error, sizeof(handle.error));
}
ret = uart_write_8(msg_size + error_size);
if (ret != 0) {
return ret;
}
/* Send the ID of next partition */
ret = uart_write_8(handle.phase);
if (ret != 0) {
return ret;
}
/* Destination address */
ret = uart_write_32(address);
if (ret != 0) {
return ret;
}
ret = uart_write_8(error_size);
if (ret != 0) {
return ret;
}
/* Additional information: message error */
if (error_size > 0U) {
ret = uart_write(handle.error, error_size);
}
return ret;
}
static int uart_download_part(void)
{
uint8_t operation = 0U;
uint8_t xor;
uint8_t byte = 0U;
uint32_t packet_number = 0U;
uint32_t packet_size = 0U;
uint32_t i = 0U;
int ret;
/* Get operation number */
ret = uart_read_8(&operation);
if (ret != 0) {
return ret;
}
xor = operation;
/* Get packet number */
for (i = 3U; i != 0U; i--) {
ret = uart_read_8(&byte);
if (ret != 0) {
return ret;
}
xor ^= byte;
packet_number = (packet_number << 8) | byte;
}
if (packet_number != handle.packet) {
WARN("UART: Bad packet number receive: %u, expected %u\n",
packet_number, handle.packet);
return -EPROTO;
}
/* Checksum */
ret = uart_read_8(&byte);
if (ret != 0) {
return ret;
}
if (xor != byte) {
VERBOSE("UART: Download Command checksum xor: %x, received %x\n",
xor, byte);
return -EPROTO;
}
ret = uart_send_result(ACK_BYTE);
if (ret != 0) {
return ret;
}
ret = uart_read_8(&byte);
if (ret != 0) {
return ret;
}
xor = byte;
packet_size = byte + 1U;
if (handle.len < packet_size) {
STM32PROG_ERROR("Download overflow at %p\n", handle.addr + packet_size);
return 0;
}
for (i = 0U; i < packet_size; i++) {
ret = uart_read_8(&byte);
if (ret != 0) {
return ret;
}
*(handle.addr + i) = byte;
xor ^= byte;
}
/* Checksum */
ret = uart_read_8(&byte) != 0;
if (ret != 0) {
return ret;
}
if (xor != byte) {
VERBOSE("UART: Download Data checksum xor: %x, received %x\n",
xor, byte);
return -EPROTO;
}
/* Packet treated */
handle.packet++;
handle.addr += packet_size;
handle.len -= packet_size;
return 0;
}
static int uart_start_cmd(uintptr_t buffer)
{
uint8_t byte = 0U;
uint8_t xor = 0U;
uint32_t i;
uint32_t start_address = 0U;
int ret;
/* Get address */
for (i = 4U; i != 0U; i--) {
ret = uart_read_8(&byte);
if (ret != 0U) {
return ret;
}
xor ^= byte;
start_address = (start_address << 8) | byte;
}
/* Checksum */
ret = uart_read_8(&byte);
if (ret != 0) {
return ret;
}
if (xor != byte) {
VERBOSE("UART: Start Command checksum xor: %x, received %x\n",
xor, byte);
return -EPROTO;
}
if (start_address != UNDEFINED_DOWN_ADDR) {
STM32PROG_ERROR("Invalid start at %x, for phase %u\n",
start_address, handle.phase);
return 0;
}
if (!is_valid_header((fip_toc_header_t *)buffer)) {
STM32PROG_ERROR("FIP Header check failed %lx, for phase %u\n",
buffer, handle.phase);
return -EIO;
}
VERBOSE("FIP header looks OK.\n");
return 0;
}
static int uart_read(uint8_t id, uintptr_t buffer, size_t length)
{
bool start_done = false;
int ret;
uint8_t command = 0U;
handle.phase = id;
handle.packet = 0U;
handle.addr = (uint8_t *)buffer;
handle.len = length;
INFO("UART: read phase %u at 0x%lx size 0x%x\n",
id, buffer, length);
while (!start_done) {
ret = uart_receive_command(&command);
if (ret != 0) {
/* Delay to wait STM32CubeProgrammer end of transmission */
mdelay(3);
ret = uart_send_result(NACK_BYTE);
if (ret != 0U) {
return ret;
}
continue;
}
uart_send_result(ACK_BYTE);
switch (command) {
case INIT_BYTE:
INFO("UART: Connected\n");
/* Nothing to do */
continue;
case GET_CMD_COMMAND:
ret = get_cmd_command();
break;
case GET_VER_COMMAND:
ret = get_version_command();
break;
case GET_ID_COMMAND:
ret = get_id_command();
break;
case PHASE_COMMAND:
ret = uart_send_phase((uint32_t)buffer);
if ((ret == 0) && (handle.phase == PHASE_RESET)) {
start_done = true;
INFO("UART: Reset\n");
}
break;
case DOWNLOAD_COMMAND:
ret = uart_download_part();
break;
case START_COMMAND:
ret = uart_start_cmd(buffer);
if ((ret == 0) && (handle.phase == id)) {
INFO("UART: Start phase %u\n", handle.phase);
start_done = true;
}
break;
default:
WARN("UART: Unknown command\n");
ret = -EINVAL;
break;
}
if (ret == 0) {
ret = uart_send_result(ACK_BYTE);
} else {
ret = uart_send_result(NACK_BYTE);
}
if (ret != 0) {
return ret;
}
}
return 0;
}
/* Init UART: 115200, 8bit 1stop parity even and enable FIFO mode */
const struct stm32_uart_init_s init = {
.baud_rate = U(115200),
.word_length = STM32_UART_WORDLENGTH_9B,
.stop_bits = STM32_UART_STOPBITS_1,
.parity = STM32_UART_PARITY_EVEN,
.hw_flow_control = STM32_UART_HWCONTROL_NONE,
.mode = STM32_UART_MODE_TX_RX,
.over_sampling = STM32_UART_OVERSAMPLING_16,
.fifo_mode = STM32_UART_FIFOMODE_EN,
};
int stm32cubeprog_uart_load(uintptr_t instance, uintptr_t base, size_t len)
{
int ret;
if (stm32_uart_init(&handle.uart, instance, &init) != 0) {
return -EIO;
}
/*
* The following NACK_BYTE is written because STM32CubeProgrammer has
* already sent its command before TF-A has reached this point, and
* because FIFO was not configured by BootROM.
* The byte in the UART_RX register is then the checksum and not the
* command. NACK_BYTE has to be written, so that the programmer will
* re-send the good command.
*/
ret = uart_send_result(NACK_BYTE);
if (ret != 0) {
return ret;
}
return uart_read(PHASE_SSBL, base, len);
}