Change in coreboot[master]: mb/amd/chausie: Auto-detect DDI type

[Fred Reitberger (Code Review)]

Attention is currently required from: Jason Glenesk, Marshall Dawson, Felix Held.
Fred Reitberger has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/63795 )

Change subject: mb/amd/chausie: Auto-detect DDI type
......................................................................

mb/amd/chausie: Auto-detect DDI type

Read the EEPROM to detect the DDI type.

BUG=225139014
TEST=Boot chausie and correctly detect display card type

Change-Id: I3ddd8789e75d5da2ea1e6ce9a81e5ebb2cf3c007
Signed-off-by: Fred Reitberger 
---
M src/mainboard/amd/chausie/devicetree.cb
M src/mainboard/amd/chausie/port_descriptors.c
2 files changed, 45 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/95/63795/1

diff --git a/src/mainboard/amd/chausie/devicetree.cb b/src/mainboard/amd/chausie/devicetree.cb
index 4a0c5b0..09b8500 100644
--- a/src/mainboard/amd/chausie/devicetree.cb
+++ b/src/mainboard/amd/chausie/devicetree.cb
@@ -24,6 +24,11 @@
    register "i2c_scl_reset" = "GPIO_I2C0_SCL | GPIO_I2C1_SCL |
    				GPIO_I2C2_SCL | GPIO_I2C3_SCL"

+	register "i2c[0].early_init" = "1"
+	register "i2c[1].early_init" = "1"
+	register "i2c[2].early_init" = "1"
+	register "i2c[3].early_init" = "1"
+
    # I2C Pad Control RX Select Configuration
    register "i2c_pad[0].rx_level" = "I2C_PAD_RX_1_8V"
    register "i2c_pad[1].rx_level" = "I2C_PAD_RX_1_8V"
diff --git a/src/mainboard/amd/chausie/port_descriptors.c b/src/mainboard/amd/chausie/port_descriptors.c
index 4a8a0fd..aacc6e5 100644
--- a/src/mainboard/amd/chausie/port_descriptors.c
+++ b/src/mainboard/amd/chausie/port_descriptors.c
@@ -1,5 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-only */

+#include <console/console.h>
+#include <device/i2c_simple.h>
 #include <soc/gpio.h>
 #include <soc/platform_descriptors.h>
 #include <types.h>
@@ -47,7 +49,7 @@
    },
 };

-static const fsp_ddi_descriptor chausie_ddi_descriptors[] = {
+static fsp_ddi_descriptor chausie_ddi_descriptors[] = {
    { /* DDI0 - eDP */
    	.connector_type = DDI_EDP,
    	.aux_index = DDI_AUX1,
@@ -75,10 +77,47 @@
    }
 };

+static uint8_t get_ddi1_type(void)
+{
+	const uint8_t eeprom_i2c_bus = 2;
+	const uint8_t eeprom_i2c_address = 0x55;
+	const uint16_t eeprom_connector_type_offset = 2;
+	uint8_t eeprom_connector_type_data[2];
+	uint16_t connector_type;
+
+	if (i2c_read_eeprom_bytes(eeprom_i2c_bus, eeprom_i2c_address, eeprom_connector_type_offset,
+				  eeprom_connector_type_data, sizeof(eeprom_connector_type_data))) {
+		printk(BIOS_NOTICE, "Display connector type couldn't be determined. Disabling DDI1.\n");
+		return DDI_UNUSED_TYPE;
+	}
+
+	connector_type = eeprom_connector_type_data[1] | eeprom_connector_type_data[0] << 8;
+
+	switch (connector_type) {
+	case 0xc:
+		printk(BIOS_DEBUG, "Configuring DDI1 as HDMI.\n");
+		return DDI_HDMI;
+		break;
+	case 0x13:
+		printk(BIOS_DEBUG, "Configuring DDI1 as DP.\n");
+		return DDI_DP;
+		break;
+	case 0x14:
+		printk(BIOS_DEBUG, "Configuring DDI1 as eDP.\n");
+		return DDI_EDP;
+		break;
+	default:
+		printk(BIOS_WARNING, "Unexpected display connector type %x. Disabling DDI1.\n", connector_type);
+		return DDI_UNUSED_TYPE;
+	}
+}
+
 void mainboard_get_dxio_ddi_descriptors(
    	const fsp_dxio_descriptor **dxio_descs, size_t *dxio_num,
    	const fsp_ddi_descriptor **ddi_descs, size_t *ddi_num)
 {
+	chausie_ddi_descriptors[1].connector_type = get_ddi1_type();
+
    *dxio_descs = chausie_dxio_descriptors;
    *dxio_num = ARRAY_SIZE(chausie_dxio_descriptors);
    *ddi_descs = chausie_ddi_descriptors;