Furquan Shaikh has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/39340 )
Change subject: chromeos: remove get_write_protect_state function ......................................................................
Patch Set 3:
(1 comment)
https://review.coreboot.org/c/coreboot/+/39340/3/src/drivers/mrc_cache/mrc_c... File src/drivers/mrc_cache/mrc_cache.c:
https://review.coreboot.org/c/coreboot/+/39340/3/src/drivers/mrc_cache/mrc_c... PS3, Line 438: /* Read Write Protect GPIO if available */ : wp_gpio = get_write_protect_state(); One problem that I can think of here is: when SW WP is enabled, but HW WP isn't. In such cases, I believe the firmware updater(https://chromium.git.corp.google.com/chromiumos/platform/vboot_reference/+/5...) considers that write protection is disabled because flashrom can temporarily set status registers to 0 to allow RO+RW update.
But, if coreboot configures PRR to protect MRC cache based on SW WP only, then RO+RW update would not be able to write to MRC cache, thus resulting in firmware update failure.