Change in flashrom[master]: sb600spi.c: Use SPI100 bit mappings

[Karthik Ramasubramanian (Code Review)]

Karthik Ramasubramanian has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/63422 )

Change subject: sb600spi.c: Use SPI100 bit mappings
......................................................................

sb600spi.c: Use SPI100 bit mappings

Flashrom has been using legacy spi100 bit mappings when programming the
opcode and triggering the command. These legacy bit mappings are
deprecated in upcoming generation of AMD SoCs. Stop using the legacy
spi100 registers and use the correct ones.

BUG=b:228238107
TEST=Build and deploy flashrom in Skyrim. Ensure that flashrom is able
to detect the SPI ROM chip, read from it and write to it successfully.

Change-Id: If42130757331f4294b5a42c848557d3287f24fc3
Signed-off-by: Karthikeyan Ramasubramanian 
---
M sb600spi.c
1 file changed, 16 insertions(+), 2 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/22/63422/1

diff --git a/sb600spi.c b/sb600spi.c
index 6f8cc40..b1e140b 100644
--- a/sb600spi.c
+++ b/sb600spi.c
@@ -53,6 +53,10 @@
 #define FIFO_SIZE_OLD		8
 #define FIFO_SIZE_YANGTZE	71

+#define SPI100_CMD_CODE_REG	0x45
+#define SPI100_CMD_TRIGGER_REG	0x47
+#define   SPI100_EXECUTE_CMD	(1 << 7)
+
 struct sb600spi_data {
    struct flashctx *flash;
    uint8_t *spibar;
@@ -200,6 +204,16 @@
    msg_pspew("done\n");
 }

+static void execute_spi100_command(uint8_t *sb600_spibar)
+{
+	msg_pspew("Executing... ");
+	mmio_writeb(mmio_readb(sb600_spibar + SPI100_CMD_TRIGGER_REG) | SPI100_EXECUTE_CMD,
+			sb600_spibar + SPI100_CMD_TRIGGER_REG);
+	while (mmio_readb(sb600_spibar + SPI100_CMD_TRIGGER_REG) & SPI100_CMD_TRIGGER_REG)
+		;
+	msg_pspew("done\n");
+}
+
 static int sb600_spi_send_command(const struct flashctx *flash, unsigned int writecnt,
    			  unsigned int readcnt,
    			  const unsigned char *writearr,
@@ -299,7 +313,7 @@
    unsigned char cmd = *writearr++;
    writecnt--;
    msg_pspew("%s, cmd=0x%02x, writecnt=%d, readcnt=%d\n", __func__, cmd, writecnt, readcnt);
-	mmio_writeb(cmd, sb600_spibar + 0);
+	mmio_writeb(cmd, sb600_spibar + SPI100_CMD_CODE_REG);

int ret = check_readwritecnt(flash, writecnt, readcnt);
    if (ret != 0)
@@ -317,7 +331,7 @@
    }
    msg_pspew("\n");

-	execute_command(sb600_spibar);
+	execute_spi100_command(sb600_spibar);

msg_pspew("Reading buffer: ");
    for (count = 0; count < readcnt; count++) {