x86: quark: Turn on legacy segments decode

By default the legacy segments (A0000h-B0000h, E0000h-F0000h)
do not decode to system RAM. Turn on the decode so that we can
write configuration tables in the F segment.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>

arch/x86/cpu/quark/quark.c

@@ -72,6 +72,15 @@ static void quark_setup_bars(void)
 		       CONFIG_PCIE_ECAM_BASE | MEM_BAR_EN);
 }
 
+static void quark_enable_legacy_seg(void)
+{
+	u32 hmisc2;
+
+	hmisc2 = msg_port_read(MSG_PORT_HOST_BRIDGE, HMISC2);
+	hmisc2 |= (HMISC2_SEGE | HMISC2_SEGF | HMISC2_SEGAB);
+	msg_port_write(MSG_PORT_HOST_BRIDGE, HMISC2, hmisc2);
+}
+
 int arch_cpu_init(void)
 {
 	struct pci_controller *hose;
@@ -96,6 +105,9 @@ int arch_cpu_init(void)
 	 */
 	quark_setup_bars();
 
+	/* Turn on legacy segments (A/B/E/F) decode to system RAM */
+	quark_enable_legacy_seg();
+
 	unprotect_spi_flash();
 
 	return 0;

arch/x86/include/asm/arch-quark/quark.h

@@ -21,6 +21,13 @@
 
 /* Port 0x03: Host Bridge Message Port Registers */
 
+/* Host Miscellaneous Controls 2 */
+#define HMISC2			0x03
+
+#define HMISC2_SEGE		0x00000002
+#define HMISC2_SEGF		0x00000004
+#define HMISC2_SEGAB		0x00000010
+
 /* Host Memory I/O Boundary */
 #define HM_BOUND		0x08