[flashrom] [PATCH 1/7] sbxxx: Add spispeed parameter.

Stefan Tauner stefan.tauner at student.tuwien.ac.at
Wed Jul 10 21:21:05 CEST 2013


Allow to set the SPI clock frequency on SB600 et al. with a programmer
parameter. The default is to not change the preset value. If the parameter
is given (and matches a possible value), fast reads are disabled and the
SPI clock is set temporarily. Both registers are restored on programmer
shutdown.

Example: ./flashrom -p internal:spispeed=33 -V

Possible values for spispeed are "66/reserved", "33", "22", "16.5".

Signed-off-by: Stefan Tauner <stefan.tauner at student.tuwien.ac.at>
---
 flashrom.8 | 14 ++++++++++++++
 sb600spi.c | 47 +++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 55 insertions(+), 6 deletions(-)

diff --git a/flashrom.8 b/flashrom.8
index 67acef4..82d930c 100644
--- a/flashrom.8
+++ b/flashrom.8
@@ -345,6 +345,20 @@ syntax. The user is responsible for supplying a suitable image or leaving out th
 a layout file. This limitation might be removed in the future when we understand the details better and have
 received enough feedback from users. Please report the outcome if you had to use this option to write a chip.
 .sp
+An optional
+.B spispeed
+parameter specifies the frequency of the SPI bus where applicable (i.e.\& SB600 or later with SPI flash chip
+directly attached to the chipset).
+Syntax is
+.sp
+.B "  flashrom \-p internal:spispeed=frequency"
+.sp
+where
+.B frequency
+can be
+.BR 16.5 ", " 22 ", " 33 " or " 66/reserved "
+(in MHz). The default is to not change the preset value. The use of this parameter also disables Fast Reads.
+.sp
 .TP
 .B Intel chipsets
 .sp
diff --git a/sb600spi.c b/sb600spi.c
index 7043aec..c64e330 100644
--- a/sb600spi.c
+++ b/sb600spi.c
@@ -206,15 +206,41 @@ static const struct spi_programmer spi_programmer_sb600 = {
 	.write_aai = default_spi_write_aai,
 };
 
+struct spispeed {
+	const char *const name;
+	const int8_t speed;
+};
+
 int sb600_probe_spi(struct pci_dev *dev)
 {
 	struct pci_dev *smbus_dev;
 	uint32_t tmp;
 	uint8_t reg;
 	bool amd_imc_force = false;
-	static const char *const speed_names[4] = {
-		"66/reserved", "33", "22", "16.5"
+	int8_t spispeed_idx = -1;
+	static const struct spispeed spispeeds[] = {
+		{ "66/reserved",	0x00 },
+		{ "33",			0x01 },
+		{ "22",			0x02 },
+		{ "16.5",		0x03 },
 	};
+	
+	char *spispeed = extract_programmer_param("spispeed");
+	if (spispeed != NULL) {
+		int i;
+		for (i = 0; i < ARRAY_SIZE(spispeeds); i++) {
+			if (!strcasecmp(spispeeds[i].name, spispeed)) {
+				spispeed_idx = i;
+				break;
+			}
+		}
+		if (spispeed_idx < 0) {
+			msg_perr("Error: Invalid spispeed value: '%s'.\n", spispeed);
+			free(spispeed);
+			return 1;
+		}
+		free(spispeed);
+	}
 
 	char *arg = extract_programmer_param("amd_imc_force");
 	if (arg && !strcmp(arg, "yes")) {
@@ -260,9 +286,18 @@ int sb600_probe_spi(struct pci_dev *dev)
 	 * Set bit 5, otherwise SPI accesses are pointless in LPC mode.
 	 * See doc 42413 AMD SB700/710/750 RPR.
 	 */
-	msg_pdbg("PrefetchEnSPIFromHost=%i, SpiOpEnInLpcMode=%i\n",
-		     tmp & 0x1, (tmp & 0x20) >> 5);
-	tmp = mmio_readl(sb600_spibar);
+	msg_pdbg("PrefetchEnSPIFromHost=%i, SpiOpEnInLpcMode=%i\n", tmp & 0x1, (tmp & 0x20) >> 5);
+
+	if (spispeed_idx >= 0) {
+		uint8_t speed = spispeeds[spispeed_idx].speed;
+		msg_pdbg("Setting SPI clock to %s MHz (0x%x) and disabling fast reads...",
+			 spispeeds[spispeed_idx].name, speed);
+		rmmio_writeb((mmio_readb(sb600_spibar + 0xd) & ~(0x3 << 4)) | (speed << 4), sb600_spibar + 0xd);
+		rmmio_writel(mmio_readl(sb600_spibar + 0x0) & ~(0x1 << 18), sb600_spibar + 0x0);
+		msg_pdbg(" done\n");
+	}
+
+	tmp = mmio_readl(sb600_spibar + 0x0);
 	/* FIXME: If SpiAccessMacRomEn or SpiHostAccessRomEn are zero on
 	 * SB700 or later, reads and writes will be corrupted. Abort in this
 	 * case. Make sure to avoid this check on SB600.
@@ -275,7 +310,7 @@ int sb600_probe_spi(struct pci_dev *dev)
 		     (tmp >> 23) & 0x1, (tmp >> 24) & 0x7,
 		     (tmp >> 27) & 0x1, (tmp >> 28) & 0x1);
 	tmp = (mmio_readb(sb600_spibar + 0xd) >> 4) & 0x3;
-	msg_pdbg("NormSpeed is %s MHz\n", speed_names[tmp]);
+	msg_pdbg("NormSpeed is %s MHz\n", spispeeds[tmp].name);
 
 	/* Look for the SMBus device. */
 	smbus_dev = pci_dev_find(0x1002, 0x4385);
-- 
Kind regards, Stefan Tauner





More information about the flashrom mailing list