[L] Change in coreboot[main]: soc/mediatek/mt8196: Add mtcmos init support

[Yidi Lin (Code Review)]

Attention is currently required from: Guangjie Song, Hung-Te Lin, Jarried Lin, Yu-Ping Wu.

Yidi Lin has posted comments on this change by Jarried Lin. ( https://review.coreboot.org/c/coreboot/+/84497?usp=email )

Change subject: soc/mediatek/mt8196: Add mtcmos init support
......................................................................

Patch Set 34:

(2 comments)

File src/soc/mediatek/mt8196/mtcmos.c:

https://review.coreboot.org/c/coreboot/+/84497/comment/f2d69c42_004158bf?usp... :
PS34, Line 150: 	CB_TYPE_PRE_OFF_SRAM,
              : 	CB_TYPE_POST_ON_SRAM,
we don't need them in our case.

https://review.coreboot.org/c/coreboot/+/84497/comment/5b19c94a_bac170b5?usp... :
PS34, Line 368: int mtcmos_cb_register(struct mtcmos_cb *cb)
              : {
              : 	struct mtcmos_cb *item = NULL;
              : 	bool exist = false;
              : 
              : 	if (!cb) {
              : 		printk(BIOS_ERR, "node is NULL\n");
              : 		return -EINVAL;
              : 	}
              : 
              : 	if (!cb->name) {
              : 		printk(BIOS_ERR, "callback name NULL\n");
              : 		return -EINVAL;
              : 	}
              : 
              : 	if (!cb->pre_off && !cb->pre_on && !cb->post_on && !cb->post_off) {
              : 		printk(BIOS_ERR, "callback api NULL\n");
              : 		return -EINVAL;
              : 	}
              : 
              : 	/* add node to link list */
              : 	list_for_each(item, mtcmos_cb_head, node) {
              : 		if (!strcmp(item->name, cb->name)) {
              : 			exist = true;
              : 			break;
              : 		}
              : 	}
              : 	if (exist) {
              : 		printk(BIOS_ERR, "ERR: %s exist\n", cb->name);
              : 		return -EEXIST;
              : 	}
              : 
              : 	list_insert_after(&cb->node, &mtcmos_cb_head);
              : 	return 0;
              : }
              : 
              : static int mtcmos_callback(u32 id, enum mtcmos_cb_type type)
              : {
              : 	struct mtcmos_cb *cb;
              : 	int ret = 0;
              : 
              : 	list_for_each(cb, mtcmos_cb_head, node) {
              : 		if (cb->id == id) {
              : 			switch (type) {
              : 			case CB_TYPE_PRE_ON:
              : 				if (cb->pre_on)
              : 					ret = cb->pre_on();
              : 				break;
              : 			case CB_TYPE_POST_ON:
              : 				if (cb->post_on)
              : 					ret = cb->post_on();
              : 				break;
              : 			case CB_TYPE_PRE_OFF:
              : 				if (cb->pre_off)
              : 					ret = cb->pre_off();
              : 				break;
              : 			case CB_TYPE_POST_OFF:
              : 				if (cb->post_off)
              : 					ret = cb->post_off();
              : 				break;
              : 			case CB_TYPE_POST_ON_SRAM:
              : 				if (cb->post_on_sram)
              : 					ret = cb->post_on_sram();
              : 				break;
              : 			case CB_TYPE_PRE_OFF_SRAM:
              : 				if (cb->pre_off_sram)
              : 					ret = cb->pre_off_sram();
              : 				break;
              : 			default:
              : 				printk(BIOS_ERR, "%s(%u, %d) invalid type\n", __func__, id, type);
              : 				return -EINVAL;
              : 			}
              : 
              : 			if (ret)
              : 				break;
              : 		}
              : 	}
              : 
              : 	if (ret)
              : 		printk(BIOS_ERR, "%s(%u, %d) failed(%d)\n", __func__, id, type, ret);
              : 
              : 	return ret;
              : }
              : 
              : static inline int mtcmos_pre_on_callback(u32 id)
              : {
              : 	return mtcmos_callback(id, CB_TYPE_PRE_ON);
              : }
              : 
              : static inline int mtcmos_pre_off_callback(u32 id)
              : {
              : 	return mtcmos_callback(id, CB_TYPE_PRE_OFF);
              : }
              : 
              : static inline int mtcmos_post_on_callback(u32 id)
              : {
              : 	return mtcmos_callback(id, CB_TYPE_POST_ON);
              : }
              : 
              : static inline int mtcmos_post_off_callback(u32 id)
              : {
              : 	return mtcmos_callback(id, CB_TYPE_POST_OFF);
              : }
              : 
              : static inline int mtcmos_pre_off_sram_callback(u32 id)
              : {
              : 	return mtcmos_callback(id, CB_TYPE_PRE_OFF_SRAM);
              : }
              : 
              : static inline int mtcmos_post_on_sram_callback(u32 id)
              : {
              : 	return mtcmos_callback(id, CB_TYPE_POST_ON_SRAM);
              : }
I don't think it is worth to add such complex logic to register the callback for only for `4` types of mtcmos? (1 in mtcmos.c and 3 in mmfra_pd.c)

These 4 types only need `PRE_ON`, `POST_ON`, `PRE_OFF` and `POST_OFF` settings.
Can we just simplify them like this ?
```
mtcmos_disp_vcore_pre_on();
mtcmos_ctrl(MTCMOS_ID_DISP_VCORE, MTCMOS_POWER_ON);
mtcmos_disp_vcore_post_on();
```