mb/google/nissa/var/joxer: Configure descriptor for eMMC or UFS

Joxer will have both eMMC and UFS SKUs, which require different
settings in the descriptor. So update the descriptor at run-time based
on fw_config.

By default, the descriptor is configured for UFS. This configuration
still boots fine on eMMC SKUs, it just might cause problems with S0ix.

This is a temporary workaround. It will be removed once we've
implemented a proper solution for configuring the descriptor differently
for different SKUs.

BUG=b:238234376
TEST=Make an identical change for nivviks. On both nivviks (eMMC) and
nirwen (UFS), check that it boots and that the logs show the descriptor
being configured as expected.

Change-Id: I14232eb773936f2ecd183687208d332136935601
Signed-off-by: Reka Norman <rekanorman@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/65870
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kangheui Won <khwon@chromium.org>

2 files changed, 45 insertions, 0 deletions

diff --git a/src/mainboard/google/brya/variants/joxer/Makefile.inc b/src/mainboard/google/brya/variants/joxer/Makefile.inc
index d38141ca24..ee9b555ab7 100644
--- a/src/mainboard/google/brya/variants/joxer/Makefile.inc
+++ b/src/mainboard/google/brya/variants/joxer/Makefile.inc
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
 bootblock-y += gpio.c
+bootblock-y += variant.c
 
 romstage-y += gpio.c
 
diff --git a/src/mainboard/google/brya/variants/joxer/variant.c b/src/mainboard/google/brya/variants/joxer/variant.c
new file mode 100644
index 0000000000..702468280d
--- /dev/null
+++ b/src/mainboard/google/brya/variants/joxer/variant.c
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <baseboard/variants.h>
+#include <console/console.h>
+#include <fw_config.h>
+#include <soc/bootblock.h>
+
+/*
+ * TODO(b/229022567): This is a workaround which will be removed once we
+ * implement a proper solution for configuring the descriptor differently for
+ * different SKUs.
+ */
+void variant_update_descriptor(void)
+{
+	/*
+	 * UfsCont1Config = "Disabled"
+	 * IshSupported = "No"
+	 */
+	struct descriptor_byte emmc_bytes[] = {
+		{ 0x1f8, 0x55 },
+		{ 0x1f9, 0x55 },
+		{ 0xc18, 0x89 },
+		{ 0xc1d, 0xb8 },
+	};
+
+	/*
+	 * UfsCont1Config = "X2"
+	 * IshSupported = "Yes"
+	 */
+	struct descriptor_byte ufs_bytes[] = {
+		{ 0x1f8, 0x95 },
+		{ 0x1f9, 0x59 },
+		{ 0xc18, 0x09 },
+		{ 0xc1d, 0x28 },
+	};
+
+	if (fw_config_probe(FW_CONFIG(STORAGE, STORAGE_UFS))) {
+		printk(BIOS_INFO, "Configuring descriptor for UFS\n");
+		configure_descriptor(ufs_bytes, ARRAY_SIZE(ufs_bytes));
+	} else {
+		printk(BIOS_INFO, "Configuring descriptor for eMMC\n");
+		configure_descriptor(emmc_bytes, ARRAY_SIZE(emmc_bytes));
+	}
+}