[S] Change in coreboot[main]: {commonlib, libpayload}: Add "has_external_display" in coreboot table

[Subrata Banik (Code Review)]

Subrata Banik has submitted this change. ( https://review.coreboot.org/c/coreboot/+/77796?usp=email )

Change subject: {commonlib, libpayload}: Add "has_external_display" in coreboot table
......................................................................

{commonlib, libpayload}: Add "has_external_display" in coreboot table

This patch introduces a new coreboot table entry named
"has_external_display" to understand if external display is attached.

This information is useful to prevent graceful shutdown by payload
when the LID is closed but an external display is present.

This piece of the information will be gathered by coreboot and passed
into the payload using this new entry aka external_display because
payload (i.e., deptcharge) doesn't have any other way to determine
if external display is available.

BUG=b:299137940
TEST=Able to build and boot google/rex.

w/o this patch:

LID closed and external display attached (HDMI) in developer mode
  (GBB 0x39):
> System is powered off by depthcharge

w/ this patch:

LID closed and external display attached (HDMI) in developer mode
  (GBB 0x39):
> Booted to OS and device is alive/usable

Change-Id: I0fa7eee4c5a50371a7a66c6ca1ac2c7d046d010b
Signed-off-by: Subrata Banik 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/77796
Reviewed-by: Eric Lai 
Reviewed-by: Nick Vaccaro 
Reviewed-by: Julius Werner 
Tested-by: build bot (Jenkins) 
---
M payloads/libpayload/include/coreboot_tables.h
M src/commonlib/include/commonlib/coreboot_tables.h
M src/drivers/intel/fsp2_0/graphics.c
M src/drivers/intel/fsp2_0/include/fsp/graphics.h
4 files changed, 34 insertions(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Julius Werner: Looks good to me, approved
  Nick Vaccaro: Looks good to me, approved
  Eric Lai: Looks good to me, approved

diff --git a/payloads/libpayload/include/coreboot_tables.h b/payloads/libpayload/include/coreboot_tables.h
index 4502e34..5c3f0c4 100644
--- a/payloads/libpayload/include/coreboot_tables.h
+++ b/payloads/libpayload/include/coreboot_tables.h
@@ -220,6 +220,11 @@
    CB_FB_ORIENTATION_RIGHT_UP = 3,
 };

+struct cb_framebuffer_flags {
+	u8 has_external_display : 1;
+	u8 reserved : 7;
+};
+
 struct cb_framebuffer {
    u32 tag;
    u32 size;
@@ -238,6 +243,8 @@
    u8 reserved_mask_pos;
    u8 reserved_mask_size;
    u8 orientation;
+	struct cb_framebuffer_flags flags;
+	u8 pad;
 };

#define CB_GPIO_ACTIVE_LOW 0
diff --git a/src/commonlib/include/commonlib/coreboot_tables.h b/src/commonlib/include/commonlib/coreboot_tables.h
index d77c5eb..94985b1 100644
--- a/src/commonlib/include/commonlib/coreboot_tables.h
+++ b/src/commonlib/include/commonlib/coreboot_tables.h
@@ -275,6 +275,11 @@
    LB_FB_ORIENTATION_RIGHT_UP = 3,
 };

+struct lb_framebuffer_flags {
+	uint8_t has_external_display : 1;
+	uint8_t reserved : 7;
+};
+
 struct lb_framebuffer {
    uint32_t tag;
    uint32_t size;
@@ -293,7 +298,8 @@
    uint8_t reserved_mask_pos;
    uint8_t reserved_mask_size;
    uint8_t orientation;
-	uint8_t pad[2];
+	struct lb_framebuffer_flags flags;
+	uint8_t pad;
 };

struct lb_gpio {
diff --git a/src/drivers/intel/fsp2_0/graphics.c b/src/drivers/intel/fsp2_0/graphics.c
index 6514209..a98f3bb 100644
--- a/src/drivers/intel/fsp2_0/graphics.c
+++ b/src/drivers/intel/fsp2_0/graphics.c
@@ -54,6 +54,13 @@
    FW_SPLASH_SCREEN_ENABLED,
 };

+/* Check and report if an external display is attached */
+__weak int fsp_soc_report_external_display(void)
+{
+	/* Default implementation, on-board display enabled */
+	return 0;
+}
+
 /*
  * Update elog with Firmware Splash Screen related information
  * based on enum fw_splash_screen_status.
@@ -123,6 +130,9 @@
    	.reserved_mask_pos   = fbinfo->rsvd.pos,
    	.reserved_mask_size  = fbinfo->rsvd.size,
    	.orientation         = orientation,
+		.flags = {
+			.has_external_display = fsp_soc_report_external_display(),
+		},
    };

fb_add_framebuffer_info_ex(&fb);
diff --git a/src/drivers/intel/fsp2_0/include/fsp/graphics.h b/src/drivers/intel/fsp2_0/include/fsp/graphics.h
index dfd7b4e..a5f781f 100644
--- a/src/drivers/intel/fsp2_0/include/fsp/graphics.h
+++ b/src/drivers/intel/fsp2_0/include/fsp/graphics.h
@@ -14,4 +14,14 @@
 void fsp_report_framebuffer_info(const uintptr_t framebuffer_bar,
    			 enum lb_fb_orientation orientation);

+/* SoC Overrides */
+/*
+ * Check and report if an external display is attached
+ *
+ * Possible return values:
+ * 1 - An external device is attached.
+ * 0 - On-board display alone.
+ */
+int fsp_soc_report_external_display(void);
+
 #endif /* _FSP2_0_GRAPHICS_H_ */