2 files changed, 21 insertions, 0 deletions
diff --git a/src/mainboard/emulation/qemu-q35/bootblock.c b/src/mainboard/emulation/qemu-q35/bootblock.c
index 13550f7e3da3..d5ca7f9ce7c8 100644
--- a/src/mainboard/emulation/qemu-q35/bootblock.c
+++ b/src/mainboard/emulation/qemu-q35/bootblock.c
@@ -14,6 +14,7 @@
 #include <device/pci_ops.h>
 #include <bootblock_common.h>
 #include <southbridge/intel/i82801ix/i82801ix.h>
+#include <console/console.h>
 
 /* Just define these here, there is no gm35.h file to include. */
 #define D0F0_PCIEXBAR_LO 0x60
@@ -39,6 +40,12 @@ static void bootblock_northbridge_init(void)
 	pci_io_write_config32(PCI_DEV(0,0,0), D0F0_PCIEXBAR_HI, reg);
 	reg = CONFIG_MMCONF_BASE_ADDRESS | 1; /* 256MiB - 0-255 buses. */
 	pci_io_write_config32(PCI_DEV(0,0,0), D0F0_PCIEXBAR_LO, reg);
+
+	/* MCFG is now active. If it's not qemu was started for machine PC */
+	if (CONFIG(BOOTBLOCK_CONSOLE) &&
+	    (pci_read_config32(PCI_DEV(0, 0, 0), D0F0_PCIEXBAR_LO) !=
+	     (CONFIG_MMCONF_BASE_ADDRESS | 1)))
+		die("You must run qemu for machine Q35 (-M q35)");
 }
 
 static void enable_spi_prefetch(void)
diff --git a/src/mainboard/emulation/qemu-q35/romstage.c b/src/mainboard/emulation/qemu-q35/romstage.c
index e409ad1e5fae..dbaead982af0 100644
--- a/src/mainboard/emulation/qemu-q35/romstage.c
+++ b/src/mainboard/emulation/qemu-q35/romstage.c
@@ -22,6 +22,18 @@
 #include <timestamp.h>
 #include <southbridge/intel/i82801ix/i82801ix.h>
 #include <program_loading.h>
+#include <device/pci_ops.h>
+
+#define D0F0_PCIEXBAR_LO 0x60
+
+static void mainboard_machine_check(void)
+{
+	/* Check that MCFG is active. If it's not qemu was started for machine PC */
+	if (!CONFIG(BOOTBLOCK_CONSOLE) &&
+	    (pci_read_config32(PCI_DEV(0, 0, 0), D0F0_PCIEXBAR_LO) !=
+	     (CONFIG_MMCONF_BASE_ADDRESS | 1)))
+		die("You must run qemu for machine Q35 (-M q35)");
+}
 
 asmlinkage void car_stage_entry(void)
 {
@@ -29,6 +41,8 @@ asmlinkage void car_stage_entry(void)
 	i82801ix_early_init();
 	console_init();
 
+	mainboard_machine_check();
+
 	cbmem_recovery(0);
 
 	timestamp_add_now(TS_START_ROMSTAGE);