[coreboot-gerrit] [XS] Change in coreboot[main]: mb/google/corsola: Distinguish MT8186T's SKU ID from MT8186

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Hung-Te Lin, Knox Chiou, Paul Menzel, Xinxiong Xu, Yang Wu, Yidi Lin.

Yu-Ping Wu has posted comments on this change by Yang Wu. ( https://review.coreboot.org/c/coreboot/+/84342?usp=email )

Change subject: mb/google/corsola: Distinguish MT8186T's SKU ID from MT8186
......................................................................

Patch Set 3:

(1 comment)

File src/mainboard/google/corsola/boardid.c:

https://review.coreboot.org/c/coreboot/+/84342/comment/dbcb6f1e_6b3be6f3?usp... :
PS2, Line 132: BOARD_GOOGLE_STEELIX
> Okay. […]

Actually, Squirtle only has one DTS file, so the SKU ID 0xfffffffe would also work for it. That leaves Voltorb the only problem here. How about we write

```
if (cached_sku_code == CROS_SKU_UNPROVISIONED) {
    printk(BIOS_WARNING, "Unprovisioned SKU code from EC: %s\n");
    if (get_cpu_id() == MTK_CPU_ID_MT8186T && !CONFIG(BOARD_GOOGLE_VOLTORB)) {
        /*
         * Distinguish MT8186T from MT8186 to select different device trees
         * in the payload. Voltorb is the only exception here, because right now
         * it uses 0x7FFFFFFF in the DTS compatible string. We'll need to change
         * that to 0x7FFFFFFE in kernel before the exception can be dropped.
         */
        cached_sku_code = CROS_SKU_UNPROVISIONED_MT8186T;
    } else if (CONFIG(BOARD_GOOGLE_STARYU_COMMON)) {
        /* Reserve last 4 bits to report PANEL_ID */
        cached_sku_code = 0x7FFFFFF0UL | panel_id();
    }
} else if (cached_sku_code == CROS_SKU_UNKNOWN) {
    printk(BIOS_WARNING, "Failed to get SKU code from EC\n");
    cached_sku_code = (get_adc_index...
}
```

and then try to update the compatible strings for Voltorb and Squirtle? Then, the `BOARD_GOOGLE_VOLTORB` exception can be dropped from the firmware code.