Cleanly validate ICH SPI preopcodes

The code should work on Linux/*BSD/MacOSX and relies on the serial code
implementation in serial.c. Support for additional platforms (Windows)
will have to be added to serial.c for this to work. For tests without a
Bus Pirate (or with non-functional serial code) it is possible to
#define FAKE_COMMUNICATION in buspirate_spi.c.
Thanks to Sean Nelson for the SPI mode settings code. I tweaked it a bit
to make configuration from a commandline easier should anybody want that
feature.

Tested-by: Sean Nelson <audiohacked@gmail.com>

Corresponding to flashrom svn r772.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Stefan Reinauer <stepan@coresystems.de>
Acked-by: Sean Nelson <audiohacked@gmail.com>

Makefile

@@ -25,7 +25,7 @@ INSTALL = install
 DIFF    = diff
 PREFIX  ?= /usr/local
 MANDIR  ?= $(PREFIX)/share/man
-CFLAGS  ?= -Os -Wall -Werror
+CFLAGS  ?= -Os -Wall -Werror -g
 EXPORTDIR ?= .
 
 OS_ARCH	= $(shell uname)
@@ -89,6 +89,9 @@ CONFIG_DUMMY ?= yes
 # Always enable Dr. Kaiser for now.
 CONFIG_DRKAISER ?= yes
 
+# Always enable Bus Pirate SPI for now.
+CONFIG_BUSPIRATESPI ?= yes
+
 # Disable wiki printing by default. It is only useful if you have wiki access.
 CONFIG_PRINT_WIKI ?= no
 
@@ -138,8 +141,18 @@ FEATURE_CFLAGS += -D'DRKAISER_SUPPORT=1'
 OBJS += drkaiser.o
 endif
 
+ifeq ($(CONFIG_BUSPIRATESPI), yes)
+FEATURE_CFLAGS += -D'BUSPIRATE_SPI_SUPPORT=1'
+OBJS += buspirate_spi.o
+endif
+
+# Ugly, but there's no elif/elseif.
 ifeq ($(CONFIG_SERPROG), yes)
 OBJS += serial.o
+else
+ifeq ($(CONFIG_BUSPIRATESPI), yes)
+OBJS += serial.o
+endif
 endif
 
 ifeq ($(CONFIG_PRINT_WIKI), yes)

buspirate_spi.c

@@ -0,0 +1,358 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2009 Carl-Daniel Hailfinger
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include "flash.h"
+#include "spi.h"
+
+/* Change this to #define if you want to test without a serial implementation */
+#undef FAKE_COMMUNICATION
+
+#ifndef FAKE_COMMUNICATION
+int buspirate_serialport_setup(char *dev)
+{
+	/* 115200bps, 8 databits, no parity, 1 stopbit */
+	sp_fd = sp_openserport(dev, 115200);
+	return 0;
+}
+
+int buspirate_serialport_shutdown(void)
+{
+	close(sp_fd);
+	return 0;
+}
+
+int serialport_write(unsigned char *buf, unsigned int writecnt)
+{
+	int tmp = 0;
+
+	while (tmp != writecnt) {
+		tmp = write(sp_fd, buf + tmp, writecnt - tmp);
+		if (tmp == -1)
+			return 1;
+		if (!tmp)
+			printf_debug("Empty write\n");
+	}
+
+	return 0;
+}
+
+int serialport_read(unsigned char *buf, unsigned int readcnt)
+{
+	int tmp = 0;
+
+	while (tmp != readcnt) {
+		tmp = read(sp_fd, buf + tmp, readcnt - tmp);
+		if (tmp == -1)
+			return 1;
+		if (!tmp)
+			printf_debug("Empty read\n");
+	}
+
+	return 0;
+}
+
+int buspirate_discard_read(void)
+{
+	int flags;
+
+	printf_debug("%s\n", __func__);
+	flags = fcntl(sp_fd, F_GETFL);
+	flags |= O_NONBLOCK;
+	fcntl(sp_fd, F_SETFL, flags);
+	sp_flush_incoming();
+	flags &= ~O_NONBLOCK;
+	fcntl(sp_fd, F_SETFL, flags);
+
+	return 0;
+}
+#else
+#define buspirate_serialport_setup(...) 0
+#define buspirate_serialport_shutdown(...) 0
+#define serialport_write(...) 0
+#define serialport_read(...) 0
+#define buspirate_discard_read(...) 0
+#endif
+
+int buspirate_sendrecv(unsigned char *buf, unsigned int writecnt, unsigned int readcnt)
+{
+	int i, ret = 0;
+
+	printf_debug("%s: write %i, read %i\n", __func__, writecnt, readcnt);
+	if (!writecnt && !readcnt) {
+		fprintf(stderr, "Zero length command!\n");
+		return 1;
+	}
+	printf_debug("Sending");
+	for (i = 0; i < writecnt; i++)
+		printf_debug(" 0x%02x", buf[i]);
+#ifdef FAKE_COMMUNICATION
+	/* Placate the caller for now. */
+	if (readcnt) {
+		buf[0] = 0x01;
+		memset(buf + 1, 0xff, readcnt - 1);
+	}
+	ret = 0;
+#else
+	if (writecnt)
+		ret = serialport_write(buf, writecnt);
+	if (ret)
+		return ret;
+	if (readcnt)
+		ret = serialport_read(buf, readcnt);
+	if (ret)
+		return ret;
+#endif
+	printf_debug(", receiving");
+	for (i = 0; i < readcnt; i++)
+		printf_debug(" 0x%02x", buf[i]);
+	printf_debug("\n");
+	return 0;
+}
+
+int buspirate_spi_init(void)
+{
+	unsigned char buf[512];
+	int ret = 0;
+	int i;
+	char *devpos = NULL;
+	char *dev = NULL;
+	int devlen;
+
+	if (programmer_param && !strlen(programmer_param)) {
+		free(programmer_param);
+		programmer_param = NULL;
+	}
+	if (programmer_param) {
+		devpos = strstr(programmer_param, "dev=");
+		if (devpos) {
+			devpos += 4;
+			devlen = strcspn(devpos, ",:");
+			if (devlen) {
+				dev = malloc(devlen + 1);
+				if (!dev) {
+					fprintf(stderr, "Out of memory!\n");
+					exit(1);
+				}
+				strncpy(dev, devpos, devlen);
+				dev[devlen] = '\0';
+			}
+		}
+		free(programmer_param);
+		programmer_param = NULL;
+	}
+	if (!dev) {
+		fprintf(stderr, "No serial device given. Use flashrom -p "
+			"buspiratespi:dev=/dev/ttyUSB0\n");
+		return 1;
+	}
+
+	ret = buspirate_serialport_setup(dev);
+	if (ret)
+		return ret;
+
+	/* This is the brute force version, but it should work. */
+	for (i = 0; i < 19; i++) {
+		/* Enter raw bitbang mode */
+		buf[0] = 0x00;
+		/* Send the command, don't read the response. */
+		ret = buspirate_sendrecv(buf, 1, 0);
+		if (ret)
+			return ret;
+		/* Read any response and discard it. */
+		ret = buspirate_discard_read();
+		if (ret)
+			return ret;
+	}
+	/* Enter raw bitbang mode */
+	buf[0] = 0x00;
+	ret = buspirate_sendrecv(buf, 1, 5);
+	if (ret)
+		return ret;
+	if (memcmp(buf, "BBIO", 4)) {
+		fprintf(stderr, "Entering raw bitbang mode failed!\n");
+		return 1;
+	}
+	printf_debug("Raw bitbang mode version %c\n", buf[4]);
+	if (buf[4] != '1') {
+		fprintf(stderr, "Can't handle raw bitbang mode version %c!\n",
+			buf[4]);
+		return 1;
+	}
+	/* Enter raw SPI mode */
+	buf[0] = 0x01;
+	ret = buspirate_sendrecv(buf, 1, 4);
+	if (memcmp(buf, "SPI", 3)) {
+		fprintf(stderr, "Entering raw SPI mode failed!\n");
+		return 1;
+	}
+	printf_debug("Raw SPI mode version %c\n", buf[3]);
+	if (buf[3] != '1') {
+		fprintf(stderr, "Can't handle raw SPI mode version %c!\n",
+			buf[3]);
+		return 1;
+	}
+
+	/* Initial setup (SPI peripherals config): Enable power, CS high, AUX */
+	buf[0] = 0x40 | 0xb;
+	ret = buspirate_sendrecv(buf, 1, 1);
+	if (ret)
+		return 1;
+	if (buf[0] != 0x01) {
+		fprintf(stderr, "Protocol error while setting power/CS/AUX!\n");
+		return 1;
+	}
+
+	/* Set speed to 8 MHz */
+	buf[0] = 0x60 | 0x7;
+	ret = buspirate_sendrecv(buf, 1, 1);
+	if (ret)
+		return 1;
+	if (buf[0] != 0x01) {
+		fprintf(stderr, "Protocol error while setting SPI speed!\n");
+		return 1;
+	}
+	
+	/* Set SPI config: output type, idle, clock edge, sample */
+	buf[0] = 0x80 | 0xa;
+	ret = buspirate_sendrecv(buf, 1, 1);
+	if (ret)
+		return 1;
+	if (buf[0] != 0x01) {
+		fprintf(stderr, "Protocol error while setting SPI config!\n");
+		return 1;
+	}
+
+	/* De-assert CS# */
+	buf[0] = 0x03;
+	ret = buspirate_sendrecv(buf, 1, 1);
+	if (ret)
+		return 1;
+	if (buf[0] != 0x01) {
+		fprintf(stderr, "Protocol error while raising CS#!\n");
+		return 1;
+	}
+
+	buses_supported = CHIP_BUSTYPE_SPI;
+	spi_controller = SPI_CONTROLLER_BUSPIRATE;
+
+	return 0;
+}
+
+int buspirate_spi_shutdown(void)
+{
+	unsigned char buf[5];
+	int ret = 0;
+
+	/* Exit raw SPI mode (enter raw bitbang mode) */
+	buf[0] = 0x00;
+	ret = buspirate_sendrecv(buf, 1, 5);
+	if (ret)
+		return ret;
+	if (memcmp(buf, "BBIO", 4)) {
+		fprintf(stderr, "Entering raw bitbang mode failed!\n");
+		return 1;
+	}
+	printf_debug("Raw bitbang mode version %c\n", buf[4]);
+	if (buf[4] != '1') {
+		fprintf(stderr, "Can't handle raw bitbang mode version %c!\n",
+			buf[4]);
+		return 1;
+	}
+	/* Reset Bus Pirate (return to user terminal) */
+	buf[0] = 0x0f;
+	ret = buspirate_sendrecv(buf, 1, 0);
+	if (ret)
+		return ret;
+
+	/* Shut down serial port communication */
+	ret = buspirate_serialport_shutdown();
+	if (ret)
+		return ret;
+	printf_debug("Bus Pirate shutdown completed.\n");
+
+	return 0;
+}
+
+int buspirate_spi_send_command(unsigned int writecnt, unsigned int readcnt,
+		const unsigned char *writearr, unsigned char *readarr)
+{
+	static unsigned char *buf = NULL;
+	int i = 0, ret = 0;
+
+	if (writecnt > 16 || readcnt > 16 || (readcnt + writecnt) > 16)
+		return SPI_INVALID_LENGTH;
+
+	/* +2 is pretty arbitrary. */
+	buf = realloc(buf, writecnt + readcnt + 2);
+	if (!buf) {
+		fprintf(stderr, "Out of memory!\n");
+		exit(1); // -1
+	}
+
+	/* Assert CS# */
+	buf[i++] = 0x02;
+	ret = buspirate_sendrecv(buf, 1, 1);
+	if (ret)
+		return SPI_GENERIC_ERROR;
+	if (buf[0] != 0x01) {
+		fprintf(stderr, "Protocol error while lowering CS#!\n");
+		return SPI_GENERIC_ERROR;
+	}
+
+	i = 0;
+	buf[i++] = 0x10 | (writecnt + readcnt - 1);
+	memcpy(buf + i, writearr, writecnt);
+	i += writecnt;
+	memset(buf + i, 0, readcnt);
+	ret = buspirate_sendrecv(buf, i + readcnt, i + readcnt);
+	if (ret)
+		return SPI_GENERIC_ERROR;
+	if (buf[0] != 0x01) {
+		fprintf(stderr, "Protocol error while reading/writing SPI!\n");
+		return SPI_GENERIC_ERROR;
+	}
+	memcpy(readarr, buf + i, readcnt);
+
+	i = 0;
+	/* De-assert CS# */
+	buf[i++] = 0x03;
+	ret = buspirate_sendrecv(buf, 1, 1);
+	if (ret)
+		return SPI_GENERIC_ERROR;
+	if (buf[0] != 0x01) {
+		fprintf(stderr, "Protocol error while raising CS#!\n");
+		return SPI_GENERIC_ERROR;
+	}
+
+	return ret;
+}
+
+int buspirate_spi_read(struct flashchip *flash, uint8_t *buf, int start, int len)
+{
+	/* Maximum read length is 12 bytes, use 8 for now. */
+	return spi_read_chunked(flash, buf, start, len, 8);
+}
+
+/* We could do 12-byte writes, but for now we use the generic 1-byte code. */

flash.h

@@ -103,6 +103,9 @@ enum programmer {
 #endif
 #if SERPROG_SUPPORT == 1
 	PROGRAMMER_SERPROG,
+#endif
+#if BUSPIRATE_SPI_SUPPORT == 1
+	PROGRAMMER_BUSPIRATESPI,
 #endif
 	PROGRAMMER_INVALID /* This must always be the last entry. */
 };
@@ -484,6 +487,12 @@ int bitbang_spi_send_command(unsigned int writecnt, unsigned int readcnt, const
 int bitbang_spi_read(struct flashchip *flash, uint8_t *buf, int start, int len);
 int bitbang_spi_write_256(struct flashchip *flash, uint8_t *buf);
 
+/* buspirate_spi.c */
+int buspirate_spi_init(void);
+int buspirate_spi_shutdown(void);
+int buspirate_spi_send_command(unsigned int writecnt, unsigned int readcnt, const unsigned char *writearr, unsigned char *readarr);
+int buspirate_spi_read(struct flashchip *flash, uint8_t *buf, int start, int len);
+
 /* flashrom.c */
 extern char *programmer_param;
 extern int verbose;
@@ -526,6 +535,9 @@ enum spi_controller {
 #endif
 #if DUMMY_SUPPORT == 1
 	SPI_CONTROLLER_DUMMY,
+#endif
+#if BUSPIRATE_SPI_SUPPORT == 1
+	SPI_CONTROLLER_BUSPIRATE,
 #endif
 	SPI_CONTROLLER_INVALID /* This must always be the last entry. */
 };

flashrom.c

@@ -204,6 +204,25 @@ const struct programmer_entry programmer_table[] = {
 	},
 #endif
 
+#if BUSPIRATE_SPI_SUPPORT == 1
+	{
+		.name			= "buspiratespi",
+		.init			= buspirate_spi_init,
+		.shutdown		= buspirate_spi_shutdown,
+		.map_flash_region	= fallback_map,
+		.unmap_flash_region	= fallback_unmap,
+		.chip_readb		= noop_chip_readb,
+		.chip_readw		= fallback_chip_readw,
+		.chip_readl		= fallback_chip_readl,
+		.chip_readn		= fallback_chip_readn,
+		.chip_writeb		= noop_chip_writeb,
+		.chip_writew		= fallback_chip_writew,
+		.chip_writel		= fallback_chip_writel,
+		.chip_writen		= fallback_chip_writen,
+		.delay			= internal_delay,
+	},
+#endif
+
 	{}, /* This entry corresponds to PROGRAMMER_INVALID. */
 };
 

spi.c

@@ -100,6 +100,15 @@ const struct spi_programmer spi_programmer[] = {
 	},
 #endif
 
+#if BUSPIRATE_SPI_SUPPORT == 1
+	{ /* SPI_CONTROLLER_BUSPIRATE */
+		.command = buspirate_spi_send_command,
+		.multicommand = default_spi_send_multicommand,
+		.read = buspirate_spi_read,
+		.write_256 = spi_chip_write_1,
+	},
+#endif
+
 	{}, /* This entry corresponds to SPI_CONTROLLER_INVALID. */
 };
 

spi.h

@@ -106,6 +106,7 @@
 #define JEDEC_BYTE_PROGRAM_INSIZE	0x00
 
 /* Error codes */
+#define SPI_GENERIC_ERROR	-1
 #define SPI_INVALID_OPCODE	-2
 #define SPI_INVALID_ADDRESS	-3
 #define SPI_INVALID_LENGTH	-4