soc/intel/skylake: Fix SPI WP disable status check
Use SPI write protect disable bit from BIOS_CONTROL register
to check write protect status.
Change-Id: Ie79fb4e3e92a4ae777c5d501abbb44a732a9862a
Signed-off-by: Ravi Sarawadi <ravishankar.sarawadi@intel.com>
Reviewed-on: https://review.coreboot.org/21449
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/soc/intel/common/block/fast_spi/fast_spi.c b/src/soc/intel/common/block/fast_spi/fast_spi.c
index 078e0ae1..87cafb9 100644
--- a/src/soc/intel/common/block/fast_spi/fast_spi.c
+++ b/src/soc/intel/common/block/fast_spi/fast_spi.c
@@ -274,3 +274,21 @@
/* Initialize SPI to allow BIOS to write/erase on flash. */
fast_spi_init();
}
+
+/* Read SPI Write Protect disable status. */
+bool fast_spi_wpd_status(void)
+{
+ return pci_read_config16(PCH_DEV_SPI, SPIBAR_BIOS_CONTROL) &
+ SPIBAR_BIOS_CONTROL_WPD;
+}
+
+/* Enable SPI Write Protect. */
+void fast_spi_enable_wp(void)
+{
+ device_t dev = PCH_DEV_SPI;
+ uint8_t bios_cntl;
+
+ bios_cntl = pci_read_config8(dev, SPIBAR_BIOS_CONTROL);
+ bios_cntl &= ~SPIBAR_BIOS_CONTROL_WPD;
+ pci_write_config8(dev, SPIBAR_BIOS_CONTROL, bios_cntl);
+}
diff --git a/src/soc/intel/common/block/include/intelblocks/fast_spi.h b/src/soc/intel/common/block/include/intelblocks/fast_spi.h
index 086143b..6499ca5 100644
--- a/src/soc/intel/common/block/include/intelblocks/fast_spi.h
+++ b/src/soc/intel/common/block/include/intelblocks/fast_spi.h
@@ -74,11 +74,18 @@
* Caching.
*/
void fast_spi_early_init(uintptr_t spi_base_address);
-
/*
* Fast SPI flash controller structure to allow SoCs to define bus-controller
* mapping.
*/
extern const struct spi_ctrlr fast_spi_flash_ctrlr;
+/*
+ * Read SPI Write protect disable bit.
+ */
+bool fast_spi_wpd_status(void);
+/*
+ * Enable SPI Write protect.
+ */
+void fast_spi_enable_wp(void);
#endif /* SOC_INTEL_COMMON_BLOCK_FAST_SPI_H */
diff --git a/src/soc/intel/skylake/smihandler.c b/src/soc/intel/skylake/smihandler.c
index 3e79065..32764c6 100644
--- a/src/soc/intel/skylake/smihandler.c
+++ b/src/soc/intel/skylake/smihandler.c
@@ -31,7 +31,6 @@
#include <pc80/mc146818rtc.h>
#include <spi-generic.h>
#include <soc/iomap.h>
-#include <soc/lpc.h>
#include <soc/nvs.h>
#include <soc/pci_devs.h>
#include <soc/pch.h>
@@ -403,23 +402,22 @@
return;
if (tco_sts & (1 << 8)) { /* BIOSWR */
- u8 bios_cntl = pci_read_config16(PCH_DEV_SPI, BIOS_CNTL);
-
- if (bios_cntl & 1) {
- /*
- * BWE is RW, so the SMI was caused by a
- * write to BWE, not by a write to the BIOS
- *
- * This is the place where we notice someone
- * is trying to tinker with the BIOS. We are
- * trying to be nice and just ignore it. A more
- * resolute answer would be to power down the
- * box.
- */
- printk(BIOS_DEBUG, "Switching back to RO\n");
- pci_write_config32(PCH_DEV_SPI, BIOS_CNTL,
- (bios_cntl & ~1));
- } /* No else for now? */
+ if (IS_ENABLED(CONFIG_SPI_FLASH_SMM)) {
+ if (fast_spi_wpd_status()) {
+ /*
+ * BWE is RW, so the SMI was caused by a
+ * write to BWE, not by a write to the BIOS
+ *
+ * This is the place where we notice someone
+ * is trying to tinker with the BIOS. We are
+ * trying to be nice and just ignore it. A more
+ * resolute answer would be to power down the
+ * box.
+ */
+ printk(BIOS_DEBUG, "Switching back to RO\n");
+ fast_spi_enable_wp();
+ } /* No else for now? */
+ }
} else if (tco_sts & (1 << 3)) { /* TIMEOUT */
/* Handle TCO timeout */
printk(BIOS_DEBUG, "TCO Timeout.\n");