[coreboot-gerrit] [M] Change in coreboot[main]: mb/google/dedede/var/boxy: Add wait for HPD function

[Paul Menzel (Code Review)]

Attention is currently required from: Derek Huang, Joey Peng.

Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78146?usp=email )

Change subject: mb/google/dedede/var/boxy: Add wait for HPD function
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Patch Set 5:

(5 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/78146/comment/bea2bad2_ca4ac179 :
PS5, Line 7: Add wait for HPD function
Maybe:

Wait up to 3 s for HPD ready signal

https://review.coreboot.org/c/coreboot/+/78146/comment/3d97457b_a2d87380 :
PS5, Line 9: need
needs

https://review.coreboot.org/c/coreboot/+/78146/comment/94f0be15_3b19a19c :
PS5, Line 9: Boxy project need to wait for HPD ready to continue boot in ramstage to
           : avoid no display in DEV screen and recovery screen
Please add a dot/period at the end of sentences.

File src/mainboard/google/dedede/variants/boxy/ramstage.c:

https://review.coreboot.org/c/coreboot/+/78146/comment/d7ddc826_a576735f :
PS5, Line 67: 	static const long display_timeout_ms = 3000;
Why 3 seconds?

https://review.coreboot.org/c/coreboot/+/78146/comment/d6110ccf_948aff74 :
PS5, Line 69: if (display_init_required()
            : 		&& !gpio_get(GPIO_USB_C0_HPD)) {
            : 		/* This has to be done before FSP-S runs. */
            : 		if (google_chromeec_wait_for_displayport(display_timeout_ms)) {
            : 			wait_for_hpd(GPIO_USB_C0_HPD, display_timeout_ms);
            : 		}
            : 	} else if (display_init_required()
            : 		&& !gpio_get(GPIO_USB_C1_HPD)) {
            : 		/* This has to be done before FSP-S runs. */
            : 		if (google_chromeec_wait_for_displayport(display_timeout_ms)) {
            : 			wait_for_hpd(GPIO_USB_C1_HPD, display_timeout_ms);
            : 		}
            : 	}
Can there be two displays attached at the same time?