realtek_mst_i2c_spi.c: Fix cmd timeout issue

Chip erasures take much longer than sector and bank
erasures. Allow the wait loop helper to multiply the
max timeout in this very specific case while quickly
timeout for other ops that are expected to be shorter.

V.2: Fix nonsense fall though warn-err

BUG=b:152558985,b:148745673
BRANCH=none
TEST=flashrom -p realtek_mst_i2c_spi:bus=8 -E &&
     flashrom -p realtek_mst_i2c_spi:bus=8 -w foo
    (cycle)..

Change-Id: I4a36aa3101827e69eb244775d25bbb476d4bb780
Signed-off-by: Edward O'Callaghan <quasisec@google.com>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/41123


Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Sam McNally <sammc@google.com>

realtek_mst_i2c_spi.c

@@ -96,21 +96,22 @@ static int realtek_mst_i2c_spi_read_register(int fd, uint8_t reg, uint8_t *value
 	return ret ? SPI_GENERIC_ERROR : 0;
 }
 
-static int realtek_mst_i2c_spi_wait_command_done(int fd, unsigned int offset, int mask, int target)
+static int realtek_mst_i2c_spi_wait_command_done(int fd, unsigned int offset, int mask,
+		int target, int multiplier)
 {
 	uint8_t val;
 	int tried = 0;
 	int ret = 0;
 	do {
 		ret |= realtek_mst_i2c_spi_read_register(fd, offset, &val);
-	} while (!ret && ((val & mask) != target) && ++tried < MAX_SPI_WAIT_RETRIES);
+	} while (!ret && ((val & mask) != target) && ++tried < (MAX_SPI_WAIT_RETRIES*multiplier));
 
 	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;
+	return (val & mask) != target ? SPI_GENERIC_ERROR : ret;
 }
 
 static int realtek_mst_i2c_spi_enter_isp_mode(int fd)
@@ -130,7 +131,7 @@ static int realtek_mst_i2c_spi_enter_isp_mode(int fd)
 static int realtek_mst_i2c_execute_write(int fd)
 {
 	int ret = realtek_mst_i2c_spi_write_register(fd, MCU_MODE, START_WRITE_XFER);
-	ret |= realtek_mst_i2c_spi_wait_command_done(fd, MCU_MODE, WRITE_XFER_STATUS_MASK, 0);
+	ret |= realtek_mst_i2c_spi_wait_command_done(fd, MCU_MODE, WRITE_XFER_STATUS_MASK, 0, 1);
 	return ret;
 }
 
@@ -202,6 +203,7 @@ static int realtek_mst_i2c_spi_send_command(const struct flashctx *flash,
 				unsigned char *readarr)
 {
 	unsigned i;
+	int max_timeout_mul = 1;
 	int ret = 0;
 
 	if (writecnt > 4 || readcnt > 3 || writecnt == 0) {
@@ -239,8 +241,10 @@ static int realtek_mst_i2c_spi_send_command(const struct flashctx *flash,
 		ctrl_reg_val |= (2 << 5);
 		break;
 	/* Erasures require BIT7 && BIT5 set. */
-	case JEDEC_CE_60:
 	case JEDEC_CE_C7:
+		max_timeout_mul *= 20; /* chip erasures take much longer! */
+	/* FALLTHRU */
+	case JEDEC_CE_60:
 	case JEDEC_BE_52:
 	case JEDEC_BE_D8:
 	case JEDEC_BE_D7:
@@ -261,7 +265,7 @@ static int realtek_mst_i2c_spi_send_command(const struct flashctx *flash,
 	if (ret)
 		return ret;
 
-	ret = realtek_mst_i2c_spi_wait_command_done(fd, 0x60, 0x01, 0);
+	ret = realtek_mst_i2c_spi_wait_command_done(fd, 0x60, 0x01, 0, max_timeout_mul);
 	if (ret)
 		return ret;
 
@@ -321,7 +325,7 @@ static int realtek_mst_i2c_spi_read(struct flashctx *flash, uint8_t *buf,
 	if (ret)
 		return ret;
 
-	ret = realtek_mst_i2c_spi_wait_command_done(fd, 0x60, 0x01, 0);
+	ret = realtek_mst_i2c_spi_wait_command_done(fd, 0x60, 0x01, 0, 1);
 	if (ret)
 		return ret;
 
@@ -373,7 +377,7 @@ static int realtek_mst_i2c_spi_write_256(struct flashctx *flash, const uint8_t *
 			break;
 
 		/* Wait for empty buffer. */
-		ret |= realtek_mst_i2c_spi_wait_command_done(fd, MCU_MODE, 0x10, 0x10);
+		ret |= realtek_mst_i2c_spi_wait_command_done(fd, MCU_MODE, 0x10, 0x10, 1);
 		if (ret)
 			break;