[XS] Change in coreboot[main]: mb/google/rauru: Determine PCIe init by storage_id

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Hung-Te Lin, Yidi Lin.

Yu-Ping Wu has posted comments on this change by Yidi Lin. ( https://review.coreboot.org/c/coreboot/+/85828?usp=email )

Change subject: mb/google/rauru: Determine PCIe init by storage_id
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Patch Set 2:

(1 comment)

File src/mainboard/google/rauru/mainboard.c:

https://review.coreboot.org/c/coreboot/+/85828/comment/71713349_9ed688b7?usp... :
PS2, Line 52: 	return storage_id() == 3;
Can we modify `storage_type()` to return `enum storage_type` (by renaming `ufs_type`)? We could use the high bits to differentiate between UFS and NVMe.

```
# Bits [31:28] for base type (e.g. UFS).
#define _BASE_TYPE_SHIFT 28
#define _BASE_TYPE_MASK (0xf << _BASE_TYPE_SHIFT)
#define _BASE_TYPE(x) ((x & 0xf) << _BASE_TYPE_SHIFT)

#define _BASE_TYPE_UFS _BASE_TYPE(0x0)
#define _BASE_TYPE_NVME _BASE_TYPE(0x1)

enum storage_type {
    STORAGE_UNKNOWN = 0,
    STORAGE_UFS_31 = _BASE_TYPE_UFS | 0x310,
    ...
    STORAGE_NVME = _BASE_TYPE_NVME,
};

enum storage_type storage_type(void)
{
    uint32_t index = storage_id();
    switch (index)
        ...
}

static inline storage_is_nvme(void)
{
    return (storage_type() & _BASE_TYPE_MASK) == _BASE_TYPE_NVME;
}
```

Then we can use `storage_is_nvme` here.