Refine handling of spi_write_enable() failures to fix chip erases on ichspi

Until the ICH SPI driver can handle preopcodes as standalone opcodes,
we should handle such special opcode failure gracefully on ICH and
compatible chipsets.

This fixes chip erase on almost all ICH+VIA SPI masters.

Thanks to Ali Nadalizadeh for helping track down this bug!

Corresponding to flashrom svn r484.
Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>

it87spi.c

@@ -196,11 +196,14 @@ int it8716f_spi_command(unsigned int writecnt, unsigned int readcnt,
 }
 
 /* Page size is usually 256 bytes */
-static void it8716f_spi_page_program(int block, uint8_t *buf, uint8_t *bios)
+static int it8716f_spi_page_program(int block, uint8_t *buf, uint8_t *bios)
 {
 	int i;
+	int result;
 
-	spi_write_enable();
+	result = spi_write_enable();
+	if (result)
+		return result;
 	OUTB(0x06, it8716f_flashport + 1);
 	OUTB(((2 + (fast_spi ? 1 : 0)) << 4), it8716f_flashport);
 	for (i = 0; i < 256; i++) {
@@ -212,6 +215,7 @@ static void it8716f_spi_page_program(int block, uint8_t *buf, uint8_t *bios)
 	 */
 	while (spi_read_status_register() & JEDEC_RDSR_BIT_WIP)
 		usleep(1000);
+	return 0;
 }
 
 /*
@@ -222,12 +226,15 @@ int it8716f_over512k_spi_chip_write(struct flashchip *flash, uint8_t *buf)
 {
 	int total_size = 1024 * flash->total_size;
 	int i;
+	int result;
 
 	fast_spi = 0;
 
 	spi_disable_blockprotect();
 	for (i = 0; i < total_size; i++) {
-		spi_write_enable();
+		result = spi_write_enable();
+		if (result)
+			return result;
 		spi_byte_program(i, buf[i]);
 		while (spi_read_status_register() & JEDEC_RDSR_BIT_WIP)
 			myusec_delay(10);

sb600spi.c

@@ -68,6 +68,7 @@ int sb600_spi_write(struct flashchip *flash, uint8_t *buf)
 {
 	int rc = 0, i;
 	int total_size = flash->total_size * 1024;
+	int result;
 
 	/* Erase first */
 	printf("Erasing flash before programming... ");
@@ -77,7 +78,9 @@ int sb600_spi_write(struct flashchip *flash, uint8_t *buf)
 	printf("Programming flash");
 	for (i = 0; i < total_size; i++, buf++) {
 		spi_disable_blockprotect();
-		spi_write_enable();
+		result = spi_write_enable();
+		if (result)
+			return result;
 		spi_byte_program(i, *buf);
 		/* wait program complete. */
 		if (i % 0x8000 == 0)

spi.c

@@ -88,9 +88,24 @@ static int spi_res(unsigned char *readarr)
 int spi_write_enable(void)
 {
 	const unsigned char cmd[JEDEC_WREN_OUTSIZE] = { JEDEC_WREN };
+	int result;
 
 	/* Send WREN (Write Enable) */
-	return spi_command(sizeof(cmd), 0, cmd, NULL);
+	result = spi_command(sizeof(cmd), 0, cmd, NULL);
+	if (result) {
+		printf_debug("spi_write_enable failed");
+		switch (flashbus) {
+		case BUS_TYPE_ICH7_SPI:
+		case BUS_TYPE_ICH9_SPI:
+		case BUS_TYPE_VIA_SPI:
+			printf_debug(" due to SPI master limitation, ignoring"
+				     " and hoping it will be run as PREOP\n");
+			return 0;
+		default:
+			printf_debug("\n");
+		}
+	}
+	return result;
 }
 
 int spi_write_disable(void)
@@ -361,10 +376,8 @@ int spi_chip_erase_60(struct flashchip *flash)
 		return result;
 	}
 	result = spi_write_enable();
-	if (result) {
-		printf_debug("spi_write_enable failed\n");
+	if (result)
 		return result;
-	}
 	/* Send CE (Chip Erase) */
 	result = spi_command(sizeof(cmd), 0, cmd, NULL);
 	if (result) {
@@ -391,10 +404,8 @@ int spi_chip_erase_c7(struct flashchip *flash)
 		return result;
 	}
 	result = spi_write_enable();
-	if (result) {
-		printf_debug("spi_write_enable failed\n");
+	if (result)
 		return result;
-	}
 	/* Send CE (Chip Erase) */
 	result = spi_command(sizeof(cmd), 0, cmd, NULL);
 	if (result) {
@@ -424,11 +435,14 @@ int spi_chip_erase_60_c7(struct flashchip *flash)
 int spi_block_erase_52(const struct flashchip *flash, unsigned long addr)
 {
 	unsigned char cmd[JEDEC_BE_52_OUTSIZE] = {JEDEC_BE_52};
+	int result;
 
 	cmd[1] = (addr & 0x00ff0000) >> 16;
 	cmd[2] = (addr & 0x0000ff00) >> 8;
 	cmd[3] = (addr & 0x000000ff);
-	spi_write_enable();
+	result = spi_write_enable();
+	if (result)
+		return result;
 	/* Send BE (Block Erase) */
 	spi_command(sizeof(cmd), 0, cmd, NULL);
 	/* Wait until the Write-In-Progress bit is cleared.
@@ -447,11 +461,14 @@ int spi_block_erase_52(const struct flashchip *flash, unsigned long addr)
 int spi_block_erase_d8(const struct flashchip *flash, unsigned long addr)
 {
 	unsigned char cmd[JEDEC_BE_D8_OUTSIZE] = { JEDEC_BE_D8 };
+	int result;
 
 	cmd[1] = (addr & 0x00ff0000) >> 16;
 	cmd[2] = (addr & 0x0000ff00) >> 8;
 	cmd[3] = (addr & 0x000000ff);
-	spi_write_enable();
+	result = spi_write_enable();
+	if (result)
+		return result;
 	/* Send BE (Block Erase) */
 	spi_command(sizeof(cmd), 0, cmd, NULL);
 	/* Wait until the Write-In-Progress bit is cleared.
@@ -489,11 +506,15 @@ int spi_chip_erase_d8(struct flashchip *flash)
 int spi_sector_erase(const struct flashchip *flash, unsigned long addr)
 {
 	unsigned char cmd[JEDEC_SE_OUTSIZE] = { JEDEC_SE };
+	int result;
+	
 	cmd[1] = (addr & 0x00ff0000) >> 16;
 	cmd[2] = (addr & 0x0000ff00) >> 8;
 	cmd[3] = (addr & 0x000000ff);
 
-	spi_write_enable();
+	result = spi_write_enable();
+	if (result)
+		return result;
 	/* Send SE (Sector Erase) */
 	spi_command(sizeof(cmd), 0, cmd, NULL);
 	/* Wait until the Write-In-Progress bit is cleared.
@@ -623,6 +644,8 @@ int spi_aai_write(struct flashchip *flash, uint8_t *buf)
 {
 	uint32_t pos = 2, size = flash->total_size * 1024;
 	unsigned char w[6] = {0xad, 0, 0, 0, buf[0], buf[1]};
+	int result;
+
 	switch (flashbus) {
 	case BUS_TYPE_WBSIO_SPI:
 		fprintf(stderr, "%s: impossible with Winbond SPI masters,"
@@ -632,7 +655,9 @@ int spi_aai_write(struct flashchip *flash, uint8_t *buf)
 		break;
 	}
 	flash->erase(flash);
-	spi_write_enable();
+	result = spi_write_enable();
+	if (result)
+		return result;
 	spi_command(6, 0, w, NULL);
 	while (spi_read_status_register() & JEDEC_RDSR_BIT_WIP)
 		myusec_delay(5); /* SST25VF040B Tbp is max 10us */

wbsio_spi.c

@@ -189,6 +189,7 @@ int wbsio_spi_read(struct flashchip *flash, uint8_t *buf)
 int wbsio_spi_write(struct flashchip *flash, uint8_t *buf)
 {
 	int pos, size = flash->total_size * 1024;
+	int result;
 
 	if (flash->total_size > 1024) {
 		fprintf(stderr, "%s: Winbond saved on 4 register bits so max chip size is 1024 KB!\n", __func__);
@@ -196,7 +197,9 @@ int wbsio_spi_write(struct flashchip *flash, uint8_t *buf)
 	}
 
 	flash->erase(flash);
-	spi_write_enable();
+	result = spi_write_enable();
+	if (result)
+		return result;
 	for (pos = 0; pos < size; pos++) {
 		spi_byte_program(pos, buf[pos]);
 		while (spi_read_status_register() & JEDEC_RDSR_BIT_WIP)