Add generic SPI flash erase and write support

The first chip the code was tested and verified with is the Macronix
MX25L4005, but other chips should work as well. Timeouts are still
hardcoded to data sheet maxima, but the status register checking code is
already there. Thanks to Harald Gutmann for the initial code on which
this is loosely based.

Corresponding to flashrom svn r152 and coreboot v2 svn r2874.

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

3 files changed, 129 insertions, 6 deletions

diff --git a/flash.h b/flash.h
index 0e419ff..1fd864b 100644
--- a/flash.h
+++ b/flash.h
@@ -210,6 +210,11 @@ extern char *lb_part, *lb_vendor;
 /* spi.c */
 int probe_spi(struct flashchip *flash);
 int it87xx_probe_spi_flash(const char *name);
+int generic_spi_command(unsigned char writecnt, unsigned char readcnt, const unsigned char *writearr, unsigned char *readarr);
+void generic_spi_write_enable();
+void generic_spi_write_disable();
+int generic_spi_chip_erase(struct flashchip *flash);
+int generic_spi_chip_write(struct flashchip *flash, uint8_t *buf);
 
 /* 82802ab.c */
 int probe_82802ab(struct flashchip *flash);
diff --git a/flashchips.c b/flashchips.c
index 0c393a9..d1b471a 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -39,7 +39,7 @@ struct flashchip flashchips[] = {
 	{"Mx29f002",	MX_ID,		MX_29F002,	256, 64 * 1024,
 	 probe_29f002,	erase_29f002, 	write_29f002},
 	{"MX25L4005",	MX_ID,		MX_25L4005,	512, 4 * 1024,
-	 probe_spi,	NULL,		NULL},
+	 probe_spi,	generic_spi_chip_erase,	generic_spi_chip_write},
 	{"SST29EE020A", SST_ID,		SST_29EE020A,	256, 128,
 	 probe_jedec,	erase_chip_jedec, write_jedec},
 	{"SST28SF040A", SST_ID,		SST_28SF040,	512, 256,
diff --git a/spi.c b/spi.c
index 5dae5be..7e61b1a 100644
--- a/spi.c
+++ b/spi.c
@@ -30,11 +30,39 @@
 #define ITE_SUPERIO_PORT1	0x2e
 #define ITE_SUPERIO_PORT2	0x4e
 
+/* Read Electronic ID */
 #define JEDEC_RDID	{0x9f}
 #define JEDEC_RDID_OUTSIZE	0x01
 #define JEDEC_RDID_INSIZE	0x03
 
-static uint16_t it8716f_flashport = 0;
+/* Write Enable */
+#define JEDEC_WREN	{0x06}
+#define JEDEC_WREN_OUTSIZE	0x01
+#define JEDEC_WREN_INSIZE	0x00
+
+/* Write Disable */
+#define JEDEC_WRDI	{0x04}
+#define JEDEC_WRDI_OUTSIZE	0x01
+#define JEDEC_WRDI_INSIZE	0x00
+
+/* Both Chip Erase commands below should work */
+/* Chip Erase 0x60 */
+#define JEDEC_CE_1	{0x60};
+#define JEDEC_CE_1_OUTSIZE	0x01
+#define JEDEC_CE_1_INSIZE	0x00
+
+/* Chip Erase 0xc7 */
+#define JEDEC_CE_2	{0xc7};
+#define JEDEC_CE_2_OUTSIZE	0x01
+#define JEDEC_CE_2_INSIZE	0x00
+
+/* Read Status Register */
+#define JEDEC_RDSR	{0x05};
+#define JEDEC_RDSR_OUTSIZE	0x01
+#define JEDEC_RDSR_INSIZE	0x01
+#define JEDEC_RDSR_BIT_WIP	(0x01 << 0)
+
+uint16_t it8716f_flashport = 0;
 
 /* Generic Super I/O helper functions */
 uint8_t regval(uint16_t port, uint8_t reg)
@@ -119,6 +147,8 @@ int it87xx_probe_spi_flash(const char *name)
 static int it8716f_spi_command(uint16_t port, unsigned char writecnt, unsigned char readcnt, const unsigned char *writearr, unsigned char *readarr)
 {
 	uint8_t busy, writeenc;
+	int i;
+
 	do {
 		busy = inb(port) & 0x80;
 	} while (busy);
@@ -164,13 +194,15 @@ static int it8716f_spi_command(uint16_t port, unsigned char writecnt, unsigned c
 	do {
 		busy = inb(port) & 0x80;
 	} while (busy);
-	readarr[0] = inb(port + 5);
-	readarr[1] = inb(port + 6);
-	readarr[2] = inb(port + 7);
+
+	for (i = 0; i < readcnt; i++) {
+		readarr[i] = inb(port + 5 + i);
+	}
+
 	return 0;
 }
 
-static int generic_spi_command(unsigned char writecnt, unsigned char readcnt, const unsigned char *writearr, unsigned char *readarr)
+int generic_spi_command(unsigned char writecnt, unsigned char readcnt, const unsigned char *writearr, unsigned char *readarr)
 {
 	if (it8716f_flashport)
 		return it8716f_spi_command(it8716f_flashport, writecnt, readcnt, writearr, readarr);
@@ -188,6 +220,23 @@ static int generic_spi_rdid(unsigned char *readarr)
 	return 0;
 }
 
+void generic_spi_write_enable()
+{
+	const unsigned char cmd[] = JEDEC_WREN;
+
+	/* Send WREN (Write Enable) */
+	generic_spi_command(JEDEC_WREN_OUTSIZE, JEDEC_WREN_INSIZE, cmd, NULL);
+
+}
+
+void generic_spi_write_disable()
+{
+	const unsigned char cmd[] = JEDEC_WRDI;
+
+	/* Send WRDI (Write Disable) */
+	generic_spi_command(JEDEC_WRDI_OUTSIZE, JEDEC_WRDI_INSIZE, cmd, NULL);
+}
+
 int probe_spi(struct flashchip *flash)
 {
 	unsigned char readarr[3];
@@ -204,3 +253,72 @@ int probe_spi(struct flashchip *flash)
 	return 0;
 }
 
+uint8_t generic_spi_read_status_register()
+{
+	const unsigned char cmd[] = JEDEC_RDSR;
+	unsigned char readarr[1];
+
+	/* Read Status Register */
+	generic_spi_command(JEDEC_RDSR_OUTSIZE, JEDEC_RDSR_INSIZE, cmd, readarr);
+	return readarr[0];
+}
+
+int generic_spi_chip_erase(struct flashchip *flash)
+{
+	const unsigned char cmd[] = JEDEC_CE_2;
+
+	generic_spi_write_enable();
+	/* Send CE (Chip Erase) */
+	generic_spi_command(1, 0, cmd, NULL);
+	/* The chip needs some time for erasing, the MX25L4005A has a maximum
+	 * time of 7.5 seconds.
+	 * FIXME: Check the status register instead
+	 * Do we have to check the status register before calling
+	 * write_disable()? The data sheet suggests we don't have to call
+	 * write_disable() at all because WEL is reset automatically.
+	while (generic_spi_read_status_register() & JEDEC_RDSR_BIT_WIP)
+		sleep(1);
+	 */
+	generic_spi_write_disable();
+	sleep(8);
+	return 0;
+}
+
+void it8716f_spi_page_program(int block, uint8_t *buf, uint8_t *bios) {
+	int i;
+
+	generic_spi_write_enable();
+	outb(0x06 , it8716f_flashport + 1);
+	outb((3 << 4), it8716f_flashport);
+	for (i = 0; i < 256; i++) {
+		bios[256 * block + i] = buf[256 * block + i];
+	}
+	outb(0, it8716f_flashport);
+	/* The chip needs some time for page program, the MX25L4005A has a
+	 * maximum time of 5 ms.
+	 * FIXME: Check the status register instead.
+	 * Do we have to check the status register before calling
+	 * write_disable()? The data sheet suggests we don't have to call
+	 * write_disable() at all because WEL is reset automatically.
+	while (generic_spi_read_status_register() & JEDEC_RDSR_BIT_WIP)
+		usleep(1000);
+	 */
+	generic_spi_write_disable();
+	usleep(5000);
+}
+
+void generic_spi_page_program(int block, uint8_t *buf, uint8_t *bios)
+{
+	if (it8716f_flashport)
+		it8716f_spi_page_program(block, buf, bios);
+}
+
+int generic_spi_chip_write(struct flashchip *flash, uint8_t *buf) {
+	int total_size = 1024 * flash->total_size;
+	int i;
+	for (i = 0; i < total_size / 256; i++) {
+		generic_spi_page_program(i, buf, (uint8_t *)flash->virtual_memory);
+	}
+	return 0;
+}
+