Initial Realtek MST i2c_spi support

This spi master allows for programming of a Realtek RTD2142
MST with external SPI flash chip routed via its internal i2c
transport mechanism.

BUG=b:152558985,b:148745673
BRANCH=none
TEST=echo "00000000:0004ffff fw" > layout && \
  flashrom -p realtek_mst_i2c_spi:bus=8 -l layout -i fw:dump.bin -r && \
  flashrom -p realtek_mst_i2c_spi:bus=8 -l layout -i fw:dump.bin -w && \
  flashrom -p realtek_mst_i2c_spi:bus=8 --flash-size && \
  flashrom -p realtek_mst_i2c_spi:bus=8 --flash-name

Change-Id: I892e0be776fe605e69fb39c77abf3016591d7123
Signed-off-by: Edward O'Callaghan <quasisec@google.com>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/40667
Reviewed-by: Edward Hill <ecgh@chromium.org>
Reviewed-by: Shiyu Sun <sshiyu@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 437 insertions, 0 deletions

diff --git a/realtek_mst_i2c_spi.c b/realtek_mst_i2c_spi.c
new file mode 100644
index 000000000..ba41ed25a
--- /dev/null
+++ b/realtek_mst_i2c_spi.c
@@ -0,0 +1,437 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2020 The Chromium OS Authors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+#include <errno.h>
+
+#include "programmer.h"
+#include "spi.h"
+#include "i2c_helper.h"
+
+
+#define MCU_I2C_SLAVE_ADDR 0x94
+#define REGISTER_ADDRESS	(0x94 >> 1)
+#define PAGE_SIZE		256
+#define MAX_SPI_WAIT_RETRIES	1000
+
+//opcodes
+#define OPCODE_READ  3
+#define OPCODE_WRITE 2
+
+
+struct realtek_mst_i2c_spi_data {
+	int fd;
+};
+
+static int realtek_mst_i2c_spi_write_data(int fd, uint16_t addr, void *buf, uint16_t len)
+{
+	i2c_buffer_t data;
+	if (i2c_buffer_t_fill(&data, buf, len))
+		return SPI_GENERIC_ERROR;
+
+	return i2c_write(fd, addr, &data) == len ? 0 : SPI_GENERIC_ERROR;
+}
+
+static int realtek_mst_i2c_spi_read_data(int fd, uint16_t addr, void *buf, uint16_t len)
+{
+	i2c_buffer_t data;
+	if (i2c_buffer_t_fill(&data, buf, len))
+		return SPI_GENERIC_ERROR;
+
+	return i2c_read(fd, addr, &data) == len ? 0 : SPI_GENERIC_ERROR;
+}
+
+static int get_fd_from_context(const struct flashctx *flash)
+{
+	if (!flash || !flash->mst || !flash->mst->spi.data) {
+		msg_perr("Unable to extract fd from flash context.\n");
+		return SPI_GENERIC_ERROR;
+	}
+        const struct realtek_mst_i2c_spi_data *data =
+		(const struct realtek_mst_i2c_spi_data *)flash->mst->spi.data;
+
+	return data->fd;
+}
+
+static int realtek_mst_i2c_spi_write_register(int fd, uint8_t reg, uint8_t value)
+{
+	uint8_t command[] = { reg, value };
+	return realtek_mst_i2c_spi_write_data(fd, REGISTER_ADDRESS, command, 2);
+}
+
+static int realtek_mst_i2c_spi_read_register(int fd, uint8_t reg, uint8_t *value)
+{
+	uint8_t command[] = { reg };
+	int ret = realtek_mst_i2c_spi_write_data(fd, REGISTER_ADDRESS, command, 1);
+	ret |= realtek_mst_i2c_spi_read_data(fd, REGISTER_ADDRESS, value, 1);
+
+	return ret ? SPI_GENERIC_ERROR : 0;
+}
+
+static int realtek_mst_i2c_spi_wait_command_done(int fd, unsigned int offset, int mask)
+{
+	uint8_t val;
+	int tried = 0;
+	int ret = 0;
+	do {
+		ret |= realtek_mst_i2c_spi_read_register(fd, offset, &val);
+	} while (!ret && (val & mask) && ++tried < MAX_SPI_WAIT_RETRIES);
+
+	if (tried == MAX_SPI_WAIT_RETRIES) {
+		msg_perr("%s: Time out on sending command.\n", __func__);
+		return -MAX_SPI_WAIT_RETRIES;
+	}
+
+	return (val & mask) ? SPI_GENERIC_ERROR : ret;
+}
+
+static int realtek_mst_i2c_spi_enter_isp_mode(int fd)
+{
+	// 0xFF6F = 0x80;
+	int ret = realtek_mst_i2c_spi_write_register(fd, 0x6F, 0x80);  // enter isp mode
+
+	// set internal osc divider register to default to speed up MCU
+	// 0x06A0 = 0x74
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF4, 0x9F);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF5, 0x06);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF4, 0xA0);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF5, 0x74);
+
+	return ret;
+}
+
+static int realtek_mst_i2c_spi_reset_mpu(int fd)
+{
+	int ret = 0;
+	// 0xFFEE[1] = 1;
+	uint8_t val = 0;
+	ret |= realtek_mst_i2c_spi_read_register(fd, 0xEE, &val);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xEE, (val & 0xFD) | 0x02);
+	return ret;
+}
+
+#if 0
+static int realtek_mst_i2c_spi_set_defaults(int fd)
+{
+	// 0xFF1B = 0x02;
+	int ret = realtek_mst_i2c_spi_write_register(fd, 0x1B, 0x02);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x1C, 0x30);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x1D, 0x1C);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x1E, 0x02);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x1F, 0x00);
+
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x20, 0x1C);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x2C, 0x02);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x2D, 0x00);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x2E, 0x1C);
+
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x62, 0x06);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x6A, 0x03);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x6B, 0x0B);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0x6C, 0x00);
+
+	ret = realtek_mst_i2c_spi_write_register(fd, 0xED, 0x88);
+	ret = realtek_mst_i2c_spi_write_register(fd, 0xEE, 0x04);
+
+	return ret;
+}
+#endif
+
+static int realtek_mst_i2c_spi_disable_protection(int fd)
+{
+	int ret = 0;
+	uint8_t val = 0;
+	// 0xAB[2:0] = b001
+
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF4, 0x9F);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF5, 0x10);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF4, 0xAB);
+
+	ret |= realtek_mst_i2c_spi_read_register(fd, 0xF5, &val);
+
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF4, 0x9F);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF5, 0x10);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF4, 0xAB);
+
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xF5, (val & 0xF8) | 0x01);
+
+	/* Set pin value to high, 0xFFD7[0] = 1. */
+	ret |= realtek_mst_i2c_spi_read_register(fd, 0xD7, &val);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0xD7, (val & 0xFE) | 0x01);
+
+	return ret;
+}
+
+static int realtek_mst_i2c_spi_send_command(const struct flashctx *flash,
+				unsigned int writecnt, unsigned int readcnt,
+				const unsigned char *writearr,
+				unsigned char *readarr)
+{
+	unsigned i;
+	int ret = 0;
+
+	if (writecnt > 4 || readcnt > 3 || writecnt == 0) {
+		//msg_perr("%s: Invalid read/write count for send command.\n", __func__);
+		return SPI_GENERIC_ERROR;
+	}
+	//printf("%s: writearr[0]=0x%x\n", __func__, writearr[0]);
+
+	int fd = get_fd_from_context(flash);
+	if (fd < 0)
+		return SPI_GENERIC_ERROR;
+
+	/* First byte of writearr should be the command value, followed by the value to write. */
+	// 0xFF60 = cmd;
+	writecnt--;
+	uint8_t ctrl_reg_val = (writecnt << 3) | (readcnt << 1) | (2 << 5);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x60, ctrl_reg_val);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x61, writearr[0]);
+
+	for (i = 0; i < writecnt; ++i)
+		ret |= realtek_mst_i2c_spi_write_register(fd, 0x64 + i, writearr[i + 1]);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x60, ctrl_reg_val | 0x1);
+	if (ret)
+		return ret;
+
+	ret = realtek_mst_i2c_spi_wait_command_done(fd, 0x60, 0x01);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < readcnt; ++i)
+		ret |= realtek_mst_i2c_spi_read_register(fd, 0x67 + i, &readarr[i]);
+
+	//for (i = 0; i< readcnt; i++)
+	//	printf("DEBUG: readarr[%d]=0x%02x\n", i, readarr[i]);
+
+	return ret;
+}
+
+static int realtek_mst_i2c_spi_map_page(int fd, uint8_t block_idx, uint8_t page_idx, uint8_t byte_idx)
+{
+	int ret = 0;
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x64, block_idx);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x65, page_idx);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x66, byte_idx);
+
+	return ret ? SPI_GENERIC_ERROR : 0;
+}
+
+static int realtek_mst_i2c_spi_read(struct flashctx *flash, uint8_t *buf,
+			unsigned int start, unsigned int len)
+{
+	unsigned i;
+	int ret = 0;
+
+	if (start & 0xff)
+		return default_spi_read(flash, buf, start, len);
+
+	int fd = get_fd_from_context(flash);
+	if (fd < 0)
+		return SPI_GENERIC_ERROR;
+
+	start--;
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x60, 0x46); // **
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x61, OPCODE_READ);
+	uint8_t block_idx = start >> 16;
+	uint8_t page_idx  = start >>  8;
+	uint8_t byte_idx  = start;
+	ret |= realtek_mst_i2c_spi_map_page(fd, block_idx, page_idx, byte_idx);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x6a, 0x03);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x60, 0x47); // **
+	if (ret)
+		return ret;
+
+	ret = realtek_mst_i2c_spi_wait_command_done(fd, 0x60, 0x01);
+	if (ret)
+		return ret;
+
+	/**
+	 * The first byte is just a null, probably a status code?
+	 * Advance the read by a offset of one byte and continue.
+	 */
+	uint8_t dummy;
+	realtek_mst_i2c_spi_read_register(fd, 0x70, &dummy);
+
+	for (i = 0; i < len; i += PAGE_SIZE) {
+		ret |= realtek_mst_i2c_spi_read_data(fd, REGISTER_ADDRESS,
+				buf + i, min(len - i, PAGE_SIZE));
+		if (ret)
+			return ret;
+	}
+
+	return ret;
+}
+
+static int realtek_mst_i2c_spi_write_256(struct flashctx *flash, const uint8_t *buf,
+				unsigned int start, unsigned int len)
+{
+	unsigned i;
+	int ret = 0;
+
+	if (start & 0xff)
+		return default_spi_write_256(flash, buf, start, len);
+
+	int fd = get_fd_from_context(flash);
+	if (fd < 0)
+		return SPI_GENERIC_ERROR;
+
+	ret = realtek_mst_i2c_spi_disable_protection(fd);
+	if (ret)
+		return ret;
+
+	start--;
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x60, 0x46); // **
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x61, OPCODE_WRITE);
+	uint8_t block_idx = start >> 16;
+	uint8_t page_idx  = start >>  8;
+	uint8_t byte_idx  = start;
+	ret |= realtek_mst_i2c_spi_map_page(fd, block_idx, page_idx, byte_idx);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x6a, 0x03);
+	ret |= realtek_mst_i2c_spi_write_register(fd, 0x60, 0x47); // **
+	if (ret)
+		goto fail;
+
+	ret = realtek_mst_i2c_spi_wait_command_done(fd, 0x60, 0x01);
+	if (ret)
+		goto fail;
+
+	for (i = 0; i < len; i += PAGE_SIZE) {
+		ret |= realtek_mst_i2c_spi_write_data(fd, REGISTER_ADDRESS,
+				(uint8_t *)buf + i, min(len - i, PAGE_SIZE));
+		if (ret)
+			break;
+	}
+
+fail:
+	/* TODO: re-enable the write protection? */
+
+	return ret;
+}
+
+static int realtek_mst_i2c_spi_write_aai(struct flashctx *flash, const uint8_t *buf,
+				 unsigned int start, unsigned int len)
+{
+	msg_perr("%s: AAI write function is not supported.\n", __func__);
+	return SPI_GENERIC_ERROR;
+}
+
+static struct spi_master spi_master_i2c_realtek_mst = {
+	.max_data_read = 16,
+	.max_data_write = 8,
+	.command = realtek_mst_i2c_spi_send_command,
+	.multicommand = default_spi_send_multicommand,
+	.read = realtek_mst_i2c_spi_read,
+	.write_256 = realtek_mst_i2c_spi_write_256,
+	.write_aai = realtek_mst_i2c_spi_write_aai,
+};
+
+static int realtek_mst_i2c_spi_shutdown(void *data)
+{
+	int ret = 0;
+        struct realtek_mst_i2c_spi_data *realtek_mst_data =
+		(struct realtek_mst_i2c_spi_data *)data;
+	int fd = realtek_mst_data->fd;
+	ret |= realtek_mst_i2c_spi_reset_mpu(fd);
+	i2c_close(fd);
+	free(data);
+
+	return ret;
+}
+
+static int get_params(int *i2c_bus)
+{
+	char *bus_str = NULL;
+        int ret = SPI_GENERIC_ERROR;
+
+	bus_str = extract_programmer_param("bus");
+	if (bus_str) {
+		char *bus_suffix;
+		errno = 0;
+		int bus = (int)strtol(bus_str, &bus_suffix, 10);
+		if (errno != 0 || bus_str == bus_suffix) {
+			msg_perr("%s: Could not convert 'bus'.\n", __func__);
+			goto get_params_done;
+		}
+
+		if (bus < 0 || bus > 255) {
+			msg_perr("%s: Value for 'bus' is out of range(0-255).\n", __func__);
+			goto get_params_done;
+		}
+
+		if (strlen(bus_suffix) > 0) {
+			msg_perr("%s: Garbage following 'bus' value.\n", __func__);
+			goto get_params_done;
+		}
+
+		msg_pinfo("Using i2c bus %i.\n", bus);
+		*i2c_bus = bus;
+		ret = 0;
+		goto get_params_done;
+	} else {
+		msg_perr("%s: Bus number not specified.\n", __func__);
+	}
+get_params_done:
+	if (bus_str)
+		free(bus_str);
+
+	return ret;
+}
+
+int realtek_mst_i2c_spi_init(void)
+{
+	int ret = 0;
+	int i2c_bus = 0;
+
+	if (get_params(&i2c_bus))
+		return SPI_GENERIC_ERROR;
+
+	int fd = i2c_open(i2c_bus, REGISTER_ADDRESS, 0);
+	if (fd < 0)
+		return fd;
+
+	/* Ensure we are in a known state before entering ISP mode */
+	ret |= realtek_mst_i2c_spi_reset_mpu(fd);
+	if (ret)
+		return ret;
+
+	ret |= realtek_mst_i2c_spi_enter_isp_mode(fd);
+	if (ret)
+		return ret;
+// XXX: maybe make into a mode:defaults cli param?
+#if 0
+	ret |= realtek_mst_i2c_spi_set_defaults(fd);
+	if (ret)
+		return ret;
+#endif
+
+	struct realtek_mst_i2c_spi_data *data = calloc(1, sizeof(struct realtek_mst_i2c_spi_data));
+	if (!data) {
+		msg_perr("Unable to allocate space for extra SPI master data.\n");
+		return SPI_GENERIC_ERROR;
+	}
+
+	data->fd = fd;
+	ret |= register_shutdown(realtek_mst_i2c_spi_shutdown, data);
+
+	spi_master_i2c_realtek_mst.data = data;
+	ret |= register_spi_master(&spi_master_i2c_realtek_mst);
+
+	return ret;
+}