mb/lenovo/r500: Add mainboard

Tested:
- Ethernet NIC
- Wifi RFKill
- USB
- LVDS, VGA with libgfxinit
- Booting with dock attached (COM1)
- Keyboard, trackpoint
- SeaBIOS 1.12
- S3 resume
- Tested in descriptor mode, with vendor FD and ME
- Add VBT to ACPI OPregion

Untested:
- SATA (likely works)
- Trackpad (my cable is broken, likely works)
- Displayport (likely works)
- Descriptorless mode
- DVD drive
- Extra battery
- model with ATI GPU

Does not work:
- Dock hotplug
- Quad core CPU (hangs during AP init, probably needs hardware mod)
- Hotplugging the expresscard slot (works with 'echo 1 | sudo tee
/sys/bus/pci/rescan')

TODO:
- proper dock support
- documentation

note: This board was hard to flash, I had to desolder the flash.

TESTED: on a R500 with an Intel iGPU, SeaBIOS 1.12, Debian 9,
Linux 4.9 from USB

Change-Id: I9e129b2e916acdf2b8534fa9d8d2cfc8f64f5815
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/28644
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>

1 files changed, 15 insertions, 1 deletions

diff --git a/src/mainboard/lenovo/t400/romstage.c b/src/mainboard/lenovo/t400/romstage.c
index 6b03ad0ad8..43d6088788 100644
--- a/src/mainboard/lenovo/t400/romstage.c
+++ b/src/mainboard/lenovo/t400/romstage.c
@@ -75,7 +75,21 @@ void mb_pre_raminit_setup(sysinfo_t *sysinfo)
 	else
 		dock_info();
 
-	hybrid_graphics_init(sysinfo);
+	if (CONFIG(BOARD_LENOVO_R500)) {
+		int use_integrated = get_gpio(21);
+		printk(BIOS_DEBUG, "R500 variant found with an %s GPU\n",
+		       use_integrated ? "integrated" : "discrete");
+		if (use_integrated) {
+			sysinfo->enable_igd = 1;
+			sysinfo->enable_peg = 0;
+		} else {
+			sysinfo->enable_igd = 0;
+			sysinfo->enable_peg = 1;
+		}
+	} else {
+		hybrid_graphics_init(sysinfo);
+	}
+
 }
 
 void mb_post_raminit_setup(void)