drivers/i2c/tpm: Work around missing firmware_version in Ti50 < 0.0.15

Ti50 firmware versions below 0.0.15 don't support the firmware_version
register and trying to access it causes I2C errors. Some nissa boards
are still using Ti50 0.0.12, so add a workaround Kconfig to skip reading
the firmware version and select it for nissa. The firmware version is
only read to print it to the console, so it's fine to skip this. This
workaround will be removed once all ODM stocks are updated to 0.0.15 or
higher.

A similar workaround Kconfig was added in CB:63011 then removed in
CB:63158 which added support for separate handling of Cr50 and Ti50.
But we actually still need this workaround until all Ti50 stocks are
upgraded to 0.0.15 or higher.

BUG=b:224650720
TEST=Boot to OS on nereid with Ti50 0.0.14

Change-Id: Ia30d44ac231c42eba3ffb1cb1e6d83bb6593f926
Signed-off-by: Reka Norman <rekanorman@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64202
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

src/drivers/tpm/cr50.c

@@ -191,6 +191,13 @@ enum cb_err cr50_get_firmware_version(struct cr50_firmware_version *version)
 	    cr50_firmware_version.minor)
 		goto success;
 
+	if (CONFIG(TI50_FIRMWARE_VERSION_NOT_SUPPORTED)) {
+		printk(BIOS_ERR, "Reading Ti50 firmware version is not supported\n");
+		if (version)
+			*version = cr50_firmware_version;
+		return CB_ERR;
+	}
+
 	int chunk_count = 0;
 	size_t chunk_size = 50;
 	char version_str[301];

src/mainboard/google/brya/Kconfig

@@ -67,6 +67,7 @@ config BOARD_GOOGLE_BASEBOARD_NISSA
 	select SOC_INTEL_ALDERLAKE_PCH_N
 	select SOC_INTEL_CSE_LITE_COMPRESS_ME_RW
 	select SYSTEM_TYPE_LAPTOP
+	select TI50_FIRMWARE_VERSION_NOT_SUPPORTED
 	select TPM_GOOGLE_TI50
 
 if BOARD_GOOGLE_BRYA_COMMON

src/security/tpm/tss/vendor/cr50/Kconfig

@@ -30,4 +30,14 @@ config CR50_USE_LONG_INTERRUPT_PULSES
 	  Whether to request longer interrupt pulses using Cr50 BOARD_CFG register.
 	  If the Cr50 firmware is too old, it will not be able to honor the request.
 
+config TI50_FIRMWARE_VERSION_NOT_SUPPORTED
+	bool
+	default n
+	help
+	  Ti50 FW versions below 0.15 don't support the firmware_version register,
+	  and trying to access it causes I2C errors. This config will skip accesses
+	  to the register, and should be selected for boards using Ti50 chips with
+	  FW < 0.0.15. The config will be removed once all Ti50 stocks are updated to
+	  0.0.15 or higher.
+
 endif