[flashrom-gerrit] Change in flashrom[master]: realtek_mst_i2c_spi.c: Add ISP mode check

[Shiyu Sun (Code Review)]

Shiyu Sun has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/48662 )

Change subject: realtek_mst_i2c_spi.c: Add ISP mode check
......................................................................

realtek_mst_i2c_spi.c: Add ISP mode check

Check ISP mode before doing reset and add waiting
after the enter ISP mode command.

BUG=None
TEST=build and run mst commands

Signed-off-by: Shiyu Sun 
Change-Id: Ib1ab8370eb6335a77bb293fc98a8ab7be465db4f
---
M realtek_mst_i2c_spi.c
1 file changed, 27 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/62/48662/1

diff --git a/realtek_mst_i2c_spi.c b/realtek_mst_i2c_spi.c
index 538b07a..0126157 100644
--- a/realtek_mst_i2c_spi.c
+++ b/realtek_mst_i2c_spi.c
@@ -32,7 +32,7 @@
 #define MAX_SPI_WAIT_RETRIES	1000

#define MCU_MODE 0x6F
-#define 	ENTER_ISP_MODE 0x80
+#define 	MCU_ISP_MODE_MASK 0x80
 #define 	START_WRITE_XFER 0xA0
 #define 	WRITE_XFER_STATUS_MASK  0x20

@@ -117,10 +117,30 @@
    return (val & mask) != target ? SPI_GENERIC_ERROR : ret;
 }

+static int realtek_mst_i2c_spi_in_isp_mode(int fd)
+{
+	uint8_t mcu_mode_val;
+	int ret = realtek_mst_i2c_spi_read_register(fd, MCU_MODE, &mcu_mode_val);
+	if (ret || (mcu_mode_val & MCU_ISP_MODE_MASK) == 0)
+		return 0;
+	return 1;
+}
+
 static int realtek_mst_i2c_spi_enter_isp_mode(int fd)
 {
-	int ret = realtek_mst_i2c_spi_write_register(fd, MCU_MODE, ENTER_ISP_MODE);
+	int ret = realtek_mst_i2c_spi_write_register(fd, MCU_MODE, MCU_ISP_MODE_MASK);

+	/* wait for isp enter */
+	int retry = 10;
+	while (retry-- > 0) {
+		if (realtek_mst_i2c_spi_in_isp_mode(fd) == 1)
+			break;
+		struct timespec wait_200ms = { 0, (unsigned)2e8 };
+		nanosleep(&wait_200ms, NULL);
+	}
+
+	if (retry < 0)
+		return SPI_GENERIC_ERROR;
    // set internal osc divider register to default to speed up MCU
    // 0x06A0 = 0x74
    ret |= realtek_mst_i2c_spi_write_register(fd, 0xF4, 0x9F);
@@ -140,6 +160,11 @@

static int realtek_mst_i2c_spi_reset_mpu(int fd)
 {
+	if (realtek_mst_i2c_spi_in_isp_mode(fd) == 0) {
+		msg_perr("%s: MST not in ISP mode, reset will not happen.\n", __func__);
+		return SPI_GENERIC_ERROR;
+	}
+
    int ret = 0;
    // 0xFFEE[1] = 1;
    uint8_t val = 0;