[coreboot-gerrit] Change in coreboot[master]: soc/intel/cmn/fast_spi: Add API to clear outstanding SPI status

[Subrata Banik (Code Review)]

Subrata Banik has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/63625 )

Change subject: soc/intel/cmn/fast_spi: Add API to clear outstanding SPI status
......................................................................

soc/intel/cmn/fast_spi: Add API to clear outstanding SPI status

This patch creates a helper function to clear HSFSTS_CTL (offset 0x04)
register Bits 0 to 4.

As per Intel PCH BIOS spec section 3.6 Flash Security Recommendation,
it's important to clear all SPI outstanding status before setting SPI
lock bits.

BUG=b:211954778
TEST=Able to build google/brya with this patch and clear SPI controller
HSFSTS_CTL register Bits 0 to 4.

Signed-off-by: Subrata Banik 
Change-Id: I62adba0d0cef1d4c53b24800f90b4fe76a9d78b7
---
M src/soc/intel/common/block/fast_spi/fast_spi.c
M src/soc/intel/common/block/include/intelblocks/fast_spi.h
2 files changed, 10 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/25/63625/1

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 5a76df3..4ff1e9b 100644
--- a/src/soc/intel/common/block/fast_spi/fast_spi.c
+++ b/src/soc/intel/common/block/fast_spi/fast_spi.c
@@ -428,3 +428,11 @@
    bios_cntl |= SPI_BIOS_CONTROL_WPD;
    pci_write_config8(dev, SPI_BIOS_CONTROL, bios_cntl);
 }
+
+void fast_spi_clear_outstanding_status(void)
+{
+	void *spibar = fast_spi_get_bar();
+
+	/* Make sure all W1C status bits get cleared. */
+	write32(spibar + SPIBAR_HSFSTS_CTL, SPIBAR_HSFSTS_W1C_BITS);
+}
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 eb3f2aa..8c5067d 100644
--- a/src/soc/intel/common/block/include/intelblocks/fast_spi.h
+++ b/src/soc/intel/common/block/include/intelblocks/fast_spi.h
@@ -5,6 +5,8 @@

#include <types.h>

+/* Clear any SPI outstanding status, i.e., FCERR, FDONE etc. */
+void fast_spi_clear_outstanding_status(void);
 /* Check if SPI transaction is pending */
 int fast_spi_cycle_in_progress(void);
 /*