lspcon_i2c_spi.c: Add SPI-master support for PS17{5,6}

This adds support for the Parade lspcon usb-c to HDMI protocol
translater part that is i2c-controlled. The support allows the
host to reach the SPI ROM that hangs off the part where it
stores its firmware.

Usage is as follows:
	flashrom -p lspcon_i2c_spi:bus=X
	where X is the bus number.

BUG=b:148746232
BRANCH=none
TEST=tested with following commands, read/write/erase works good.
	flashrom -p lspcon_i2c_spi:bus=7 -r /tmp/foo;
	flashrom -p lspcon_i2c_spi:bus=7 -E;
	flashrom -p lspcon_i2c_spi:bus=7 -w /tmp/foo;

Change-Id: I039e683252cfaf1ffef8694a3e8081b1b6b944f7
Signed-off-by: Shiyu Sun <sshiyu@chromium.org>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/39687
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>

1 files changed, 505 insertions, 0 deletions

diff --git a/lspcon_i2c_spi.c b/lspcon_i2c_spi.c
new file mode 100644
index 000000000..4c8542644
--- /dev/null
+++ b/lspcon_i2c_spi.c
@@ -0,0 +1,505 @@
+/*
+ * 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 REGISTER_ADDRESS	(0x94 >> 1)
+#define PAGE_ADDRESS		(0x9e >> 1)
+#define PAGE_SIZE		256
+#define MAX_SPI_WAIT_RETRIES	1000
+
+#define CLT2_SPI		0x82
+#define SPIEDID_BASE_ADDR2	0x8d
+#define ROMADDR_BYTE1		0x8e
+#define ROMADDR_BYTE2		0x8f
+#define SWSPI_WDATA		0x90
+ #define SWSPI_WDATA_CLEAR_STATUS		0x00
+ #define SWSPI_WDATA_WRITE_REGISTER		0x01
+ #define SWSPI_WDATA_READ_REGISTER		0x05
+ #define SWSPI_WDATA_ENABLE_REGISTER		0x06
+ #define SWSPI_WDATA_SECTOR_ERASE		0x20
+ #define SWSPI_WDATA_PROTECT_BP			0x8c
+#define SWSPI_RDATA		0x91
+#define SWSPI_LEN		0x92
+#define SWSPICTL		0x93
+ #define SWSPICTL_ACCESS_TRIGGER			1
+ #define SWSPICTL_CLEAR_PTR			(1 << 1)
+ #define SWSPICTL_NO_READ			(1 << 2)
+ #define SWSPICTL_ENABLE_READBACK		(1 << 3)
+ #define SWSPICTL_MOT				(1 << 4)
+#define SPISTATUS		0x9e
+ #define SPISTATUS_BYTE_PROGRAM_FINISHED		0
+ #define SPISTATUS_BYTE_PROGRAM_IN_IF		1
+ #define SPISTATUS_BYTE_PROGRAM_SEND_DONE	(1 << 1)
+ #define SPISTATUS_SECTOR_ERASE_FINISHED		0
+ #define SPISTATUS_SECTOR_ERASE_IN_IF		(1 << 2)
+ #define SPISTATUS_SECTOR_ERASE_SEND_DONE	(1 << 3)
+ #define SPISTATUS_CHIP_ERASE_FINISHED		0
+ #define SPISTATUS_CHIP_ERASE_IN_IF		(1 << 4)
+ #define SPISTATUS_CHIP_ERASE_SEND_DONE		(1 << 5)
+ #define SPISTATUS_FW_UPDATE_ENABLE		(1 << 6)
+#define WRITE_PROTECTION	0xb3
+ #define WRITE_PROTECTION_ON			0
+ #define WRITE_PROTECTION_OFF			0x10
+#define MPU			0xbc
+#define PAGE_HW_WRITE		0xda
+ #define PAGE_HW_WRITE_DISABLE			0
+ #define PAGE_HW_COFIG_REGISTER			0xaa
+ #define PAGE_HW_WRITE_ENABLE			0x55
+
+struct lspcon_i2c_spi_data {
+	int fd;
+};
+
+typedef struct {
+	uint8_t command;
+	const uint8_t *data;
+	uint8_t data_size;
+	uint8_t control;
+} packet_t;
+
+static int lspcon_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 lspcon_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(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 lspcon_i2c_spi_data *data =
+		(const struct lspcon_i2c_spi_data *)flash->mst->spi.data;
+
+	return data->fd;
+}
+
+static int lspcon_i2c_spi_write_register(int fd, uint8_t i2c_register, uint8_t value)
+{
+	uint8_t command[] = { i2c_register, value };
+	return lspcon_i2c_spi_write_data(fd, REGISTER_ADDRESS, command, 2);
+}
+
+static int lspcon_i2c_spi_read_register(int fd, uint8_t i2c_register, uint8_t *value)
+{
+	uint8_t command[] = { i2c_register };
+	int ret = lspcon_i2c_spi_write_data(fd, REGISTER_ADDRESS, command, 1);
+	ret |= lspcon_i2c_spi_read_data(fd, REGISTER_ADDRESS, value, 1);
+
+	return ret ? SPI_GENERIC_ERROR : 0;
+}
+
+static int lspcon_i2c_spi_register_control(int fd, packet_t *packet)
+{
+	int i;
+	int ret = lspcon_i2c_spi_write_register(fd, SWSPI_WDATA, packet->command);
+	if (ret)
+		return ret;
+
+	/* Higher 4 bits are read size. */
+	int write_size = packet->data_size & 0x0f;
+	for (i = 0; i < write_size; ++i) {
+		ret |= lspcon_i2c_spi_write_register(fd, SWSPI_WDATA, packet->data[i]);
+	}
+
+	ret |= lspcon_i2c_spi_write_register(fd, SWSPI_LEN, packet->data_size);
+	ret |= lspcon_i2c_spi_write_register(fd, SWSPICTL, packet->control);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_wait_command_done(int fd, unsigned int offset, int mask)
+{
+	uint8_t val;
+	int tried = 0;
+	int ret = 0;
+	do {
+		ret |= lspcon_i2c_spi_read_register(fd, offset, &val);
+	} while(!ret && (val & mask) && ++tried < MAX_SPI_WAIT_RETRIES);
+
+	if (tried == MAX_SPI_WAIT_RETRIES) {
+		msg_perr("Error: Time out on sending command.\n");
+		return -MAX_SPI_WAIT_RETRIES;
+	}
+
+	return (val & mask) ? SPI_GENERIC_ERROR : ret;
+}
+
+static int lspcon_i2c_spi_wait_rom_free(int fd)
+{
+	uint8_t val;
+	int tried = 0;
+	int ret = 0;
+	ret |= lspcon_i2c_spi_wait_command_done(fd, SPISTATUS,
+		SPISTATUS_SECTOR_ERASE_IN_IF | SPISTATUS_SECTOR_ERASE_SEND_DONE);
+	if (ret)
+		return ret;
+
+	do {
+		packet_t packet = { SWSPI_WDATA_READ_REGISTER, NULL, 0,  SWSPICTL_ACCESS_TRIGGER };
+		ret |= lspcon_i2c_spi_register_control(fd, &packet);
+		ret |= lspcon_i2c_spi_wait_command_done(fd, SWSPICTL, SWSPICTL_ACCESS_TRIGGER);
+		ret |= lspcon_i2c_spi_read_register(fd, SWSPI_RDATA, &val);
+	} while (!ret && (val & SWSPICTL_ACCESS_TRIGGER) && ++tried < MAX_SPI_WAIT_RETRIES);
+
+	if (tried == MAX_SPI_WAIT_RETRIES) {
+		msg_perr("Error: Time out on waiting ROM free.\n");
+		return -MAX_SPI_WAIT_RETRIES;
+	}
+
+	return (val & SWSPICTL_ACCESS_TRIGGER) ? SPI_GENERIC_ERROR : ret;
+}
+
+static int lspcon_i2c_spi_toggle_register_protection(int fd, int toggle)
+{
+	return lspcon_i2c_spi_write_register(fd, WRITE_PROTECTION,
+		toggle ? WRITE_PROTECTION_OFF : WRITE_PROTECTION_ON);
+}
+
+static int lspcon_i2c_spi_enable_write_status_register(int fd)
+{
+	int ret = lspcon_i2c_spi_toggle_register_protection(fd, 1);
+	packet_t packet = {
+		SWSPI_WDATA_ENABLE_REGISTER, NULL, 0, SWSPICTL_ACCESS_TRIGGER | SWSPICTL_NO_READ };
+	ret |= lspcon_i2c_spi_register_control(fd, &packet);
+	ret |= lspcon_i2c_spi_toggle_register_protection(fd, 0);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_enable_write_status_register_protection(int fd)
+{
+	int ret = lspcon_i2c_spi_toggle_register_protection(fd, 1);
+	uint8_t data[] = { SWSPI_WDATA_PROTECT_BP };
+	packet_t packet = {
+		SWSPI_WDATA_WRITE_REGISTER, data, 1, SWSPICTL_ACCESS_TRIGGER | SWSPICTL_NO_READ };
+	ret |= lspcon_i2c_spi_register_control(fd, &packet);
+	ret |= lspcon_i2c_spi_toggle_register_protection(fd, 0);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_disable_protection(int fd)
+{
+	int ret = lspcon_i2c_spi_toggle_register_protection(fd, 1);
+	uint8_t data[] = { SWSPI_WDATA_CLEAR_STATUS };
+	packet_t packet = {
+		SWSPI_WDATA_WRITE_REGISTER, data, 1, SWSPICTL_ACCESS_TRIGGER | SWSPICTL_NO_READ };
+	ret |= lspcon_i2c_spi_register_control(fd, &packet);
+	ret |= lspcon_i2c_spi_toggle_register_protection(fd, 0);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_disable_hw_write(int fd)
+{
+	return lspcon_i2c_spi_write_register(fd, PAGE_HW_WRITE, PAGE_HW_WRITE_DISABLE);
+}
+
+static int lspcon_i2c_spi_enable_write_protection(int fd)
+{
+	int ret = lspcon_i2c_spi_enable_write_status_register(fd);
+	ret |= lspcon_i2c_spi_enable_write_status_register_protection(fd);
+	ret |= lspcon_i2c_spi_wait_rom_free(fd);
+	ret |= lspcon_i2c_spi_disable_hw_write(fd);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_disable_all_protection(int fd)
+{
+	int ret = lspcon_i2c_spi_enable_write_status_register(fd);
+	ret |= lspcon_i2c_spi_disable_protection(fd);
+	ret |= lspcon_i2c_spi_wait_rom_free(fd);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_send_command(struct flashctx *flash,
+				unsigned int writecnt, unsigned int readcnt,
+				const unsigned char *writearr,
+				unsigned char *readarr)
+{
+	unsigned int i;
+	if (writecnt > 16 || readcnt > 16 || writecnt == 0) {
+		msg_perr("Error: Invalid read/write count for send command.\n");
+		return SPI_GENERIC_ERROR;
+	}
+
+	int fd = get_fd_from_context(flash);
+	if (fd < 0)
+		return SPI_GENERIC_ERROR;
+
+	int ret = lspcon_i2c_spi_disable_all_protection(fd);
+	ret |= lspcon_i2c_spi_enable_write_status_register(fd);
+	ret |= lspcon_i2c_spi_toggle_register_protection(fd, 1);
+
+	/* First byte of writearr shuld be the command value, followed by the value to write.
+	   Read length occupies 4 bit and represents 16 level, thus if read 1 byte,
+           read length should be set 0. */
+	packet_t packet = {
+		writearr[0], &writearr[1], (writecnt - 1) | ((readcnt - 1) << 4),
+		SWSPICTL_ACCESS_TRIGGER | (readcnt ? 0 : SWSPICTL_NO_READ),
+	};
+
+	ret |= lspcon_i2c_spi_register_control(fd, &packet);
+	ret |= lspcon_i2c_spi_wait_command_done(fd, SWSPICTL, SWSPICTL_ACCESS_TRIGGER);
+	ret |= lspcon_i2c_spi_toggle_register_protection(fd, 0);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < readcnt; ++i) {
+		ret |= lspcon_i2c_spi_read_register(fd, SWSPI_RDATA, &readarr[i]);
+	}
+
+	ret |= lspcon_i2c_spi_wait_rom_free(fd);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_enable_hw_write(int fd)
+{
+	int ret = 0;
+	ret |= lspcon_i2c_spi_write_register(fd, PAGE_HW_WRITE, PAGE_HW_COFIG_REGISTER);
+	ret |= lspcon_i2c_spi_write_register(fd, PAGE_HW_WRITE, PAGE_HW_WRITE_ENABLE);
+	ret |= lspcon_i2c_spi_write_register(fd, PAGE_HW_WRITE, 0x50);
+	ret |= lspcon_i2c_spi_write_register(fd, PAGE_HW_WRITE, 0x41);
+	ret |= lspcon_i2c_spi_write_register(fd, PAGE_HW_WRITE, 0x52);
+	ret |= lspcon_i2c_spi_write_register(fd, PAGE_HW_WRITE, 0x44);
+
+	return ret;
+}
+
+static int lspcon_i2c_clt2_spi_reset(int fd)
+{
+	int ret = 0;
+	ret |= lspcon_i2c_spi_write_register(fd, CLT2_SPI, 0x20);
+	struct timespec wait_100ms = { 0, (unsigned)1e8 };
+	nanosleep(&wait_100ms, NULL);
+	ret |= lspcon_i2c_spi_write_register(fd, CLT2_SPI, 0x00);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_reset_mpu_stop(int fd)
+{
+	int ret = 0;
+	ret |= lspcon_i2c_spi_write_register(fd, MPU, 0xc0); // cmd mode
+	ret |= lspcon_i2c_spi_write_register(fd, MPU, 0x40); // stop mcu
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_map_page(int fd, unsigned int offset)
+{
+	int ret = 0;
+	/* Page number byte, need to / PAGE_SIZE. */
+	ret |= lspcon_i2c_spi_write_register(fd, ROMADDR_BYTE1, (offset >> 8) & 0xff);
+	ret |= lspcon_i2c_spi_write_register(fd, ROMADDR_BYTE2, (offset >> 16));
+
+	return ret ? SPI_GENERIC_ERROR : 0;
+}
+
+static int lspcon_i2c_spi_read(struct flashctx *flash, uint8_t *buf,
+			unsigned int start, unsigned int len)
+{
+	unsigned int 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;
+
+	for (i = 0; i < len; i += PAGE_SIZE) {
+		ret |= lspcon_i2c_spi_map_page(fd, start + i);
+		ret |= lspcon_i2c_spi_read_data(fd, PAGE_ADDRESS, buf + i, min(len - i, PAGE_SIZE));
+	}
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_write_page(int fd, const uint8_t *buf, unsigned int len)
+{
+	/**
+         * Using static buffer with maximum possible size,
+         * extra byte is needed for prefixing zero at index 0.
+         */
+	uint8_t write_buffer[PAGE_SIZE + 1] = { 0 };
+	if (len > PAGE_SIZE)
+		return SPI_GENERIC_ERROR;
+
+	/* First byte represents the writing offset and should always be zero. */
+	memcpy(&write_buffer[1], buf, len);
+
+	return lspcon_i2c_spi_write_data(fd, PAGE_ADDRESS, write_buffer, len + 1);
+}
+
+static int lspcon_i2c_spi_write_256(struct flashctx *flash, const uint8_t *buf,
+				unsigned int start, unsigned int len)
+{
+	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 |= lspcon_i2c_spi_disable_all_protection(fd);
+	/* Enable hardware write and reset clt2SPI interface. */
+	ret |= lspcon_i2c_spi_enable_hw_write(fd);
+	ret |= lspcon_i2c_clt2_spi_reset(fd);
+
+	for (unsigned int i = 0; i < len; i += PAGE_SIZE) {
+		ret |= lspcon_i2c_spi_map_page(fd, start + i);
+		ret |= lspcon_i2c_spi_write_page(fd, buf + i, min(len - i, PAGE_SIZE));
+	}
+
+	ret |= lspcon_i2c_spi_enable_write_protection(fd);
+	ret |= lspcon_i2c_spi_disable_hw_write(fd);
+
+	return ret;
+}
+
+static int lspcon_i2c_spi_write_aai(struct flashctx *flash, const uint8_t *buf,
+				 unsigned int start, unsigned int len)
+{
+	msg_perr("Error: AAI write function is not supported.\n");
+	return SPI_GENERIC_ERROR;
+}
+
+static const struct spi_master spi_master_i2c_lspcon = {
+	.max_data_read = 16,
+	.max_data_write = 12,
+	.command = lspcon_i2c_spi_send_command,
+	.multicommand = default_spi_send_multicommand,
+	.read = lspcon_i2c_spi_read,
+	.write_256 = lspcon_i2c_spi_write_256,
+	.write_aai = lspcon_i2c_spi_write_aai,
+};
+
+/* TODO: MPU still stopped at this point, probably need to reset it. */
+static int lspcon_i2c_spi_shutdown(void *data)
+{
+	int ret = 0;
+        struct lspcon_i2c_spi_data *lspcon_data =
+		(struct lspcon_i2c_spi_data *)data;
+	int fd = lspcon_data->fd;
+	ret |= lspcon_i2c_spi_enable_write_protection(fd);
+	ret |= lspcon_i2c_spi_toggle_register_protection(fd, 0);
+	i2c_close(fd);
+	free(data);
+
+	return ret;
+}
+
+/* TODO: remove this out of the specific SPI master implementation. */
+static int get_bus(void)
+{
+	char *bus_str = extract_programmer_param("bus");
+        int ret = SPI_GENERIC_ERROR;
+	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("Error: Could not convert 'bus'.\n");
+			goto get_bus_done;
+		}
+
+		if (bus < 0 || bus > 255) {
+			msg_perr("Error: Value for 'bus' is out of range(0-255).\n");
+			goto get_bus_done;
+		}
+
+		if (strlen(bus_suffix) > 0) {
+			msg_perr("Error: Garbage following 'bus' value.\n");
+			goto get_bus_done;
+		}
+
+		msg_pinfo("Using i2c bus %i.\n", bus);
+		ret = bus;
+		goto get_bus_done;
+	} else {
+		msg_perr("Error: Bus number not specified.\n");
+	}
+get_bus_done:
+	if (bus_str)
+		free(bus_str);
+
+	return ret;
+}
+
+static int register_lspcon_i2c_spi_master(void *ptr)
+{
+	struct spi_master mst = spi_master_i2c_lspcon;
+	mst.data = ptr;
+
+	return register_spi_master(&mst);
+}
+
+int lspcon_i2c_spi_init(void)
+{
+	int lspcon_i2c_spi_bus = get_bus();
+	if (lspcon_i2c_spi_bus < 0)
+		return SPI_GENERIC_ERROR;
+
+	int ret = 0;
+	int fd = i2c_open(lspcon_i2c_spi_bus, REGISTER_ADDRESS, 0);
+	if (fd < 0)
+		return fd;
+
+	ret |= lspcon_i2c_spi_reset_mpu_stop(fd);
+	if (ret)
+		return ret;
+
+	struct lspcon_i2c_spi_data *data = calloc(1, sizeof(struct lspcon_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(lspcon_i2c_spi_shutdown, data);
+	ret |= register_lspcon_i2c_spi_master(data);
+
+	return ret;
+}