[coreboot-gerrit] [XS] Change in coreboot[main]: soc/amd/common/psp_smi_flash: add spi_controller_available

[Felix Held (Code Review)]

Attention is currently required from: Fred Reitberger, Jason Glenesk, Matt DeVillier, ritul guru.

Hello ritul guru,

I'd like you to do a code review.
Please visit

https://review.coreboot.org/c/coreboot/+/83775?usp=email

to review the following change.

Change subject: soc/amd/common/psp_smi_flash: add spi_controller_available
......................................................................

soc/amd/common/psp_smi_flash: add spi_controller_available

Add the 'spi_controller_available' helper function to check
SPI_SEMAPHORE_DRIVER_LOCKED in SPI_MISC_CNTRL to see if some software or
driver outside of SMM is currently using the SPI flash controller to
avoid interfering with that operation.

This patch is a slightly reworked version of parts of CB:65523.

Test=When selecting SOC_AMD_COMMON_BLOCK_PSP_SMI, Mandolin still builds

Signed-off-by: Felix Held 
Signed-off-by: Ritul Guru 
Change-Id: I49218e03a5dd555b2b2d34eaad86673e9fc908c3
---
M src/soc/amd/common/block/psp/psp_smi_flash.c
1 file changed, 6 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/75/83775/1

diff --git a/src/soc/amd/common/block/psp/psp_smi_flash.c b/src/soc/amd/common/block/psp/psp_smi_flash.c
index 4c83fcd..367baef 100644
--- a/src/soc/amd/common/block/psp/psp_smi_flash.c
+++ b/src/soc/amd/common/block/psp/psp_smi_flash.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */

+#include <amdblocks/spi.h>
 #include <boot_device.h>
 #include <commonlib/region.h>
 #include <console/console.h>
@@ -134,6 +135,11 @@
    return MBOX_PSP_SUCCESS;
 }

+static inline bool spi_controller_available(void)
+{
+	return !(spi_read8(SPI_MISC_CNTRL) & SPI_SEMAPHORE_DRIVER_LOCKED);
+}
+
 enum mbox_p2c_status psp_smi_spi_get_info(struct mbox_default_buffer *buffer)
 {
    struct mbox_pspv2_cmd_spi_info *const cmd_buf =