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Diffstat (limited to 'src/southbridge/amd/cs5530/cs5530_enable_rom.c')
-rw-r--r--src/southbridge/amd/cs5530/cs5530_enable_rom.c47
1 files changed, 47 insertions, 0 deletions
diff --git a/src/southbridge/amd/cs5530/cs5530_enable_rom.c b/src/southbridge/amd/cs5530/cs5530_enable_rom.c
new file mode 100644
index 0000000000..09ec3ed791
--- /dev/null
+++ b/src/southbridge/amd/cs5530/cs5530_enable_rom.c
@@ -0,0 +1,47 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2009 Uwe Hermann <uwe@hermann-uwe.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include "cs5530.h"
+
+static void cs5530_enable_rom(void)
+{
+ uint8_t reg8;
+
+ /* So far all CS5530(A) ISA bridges we've seen are at 00:12.0. */
+ device_t dev = PCI_DEV(0, 0x12, 0);
+
+ /*
+ * Decode 0x000E0000-0x000FFFFF (128 KB), not just 64 KB, and
+ * decode 0xFF000000-0xFFFFFFFF (16 MB), not just 256 KB.
+ *
+ * Make the ROM write-protected.
+ */
+ reg8 = pci_read_config8(dev, ROM_AT_LOGIC_CONTROL_REG);
+ reg8 |= LOWER_ROM_ADDRESS_RANGE;
+ reg8 |= UPPER_ROM_ADDRESS_RANGE;
+ reg8 &= ~ROM_WRITE_ENABLE;
+ pci_write_config8(dev, ROM_AT_LOGIC_CONTROL_REG, reg8);
+
+ /* Set positive decode on ROM. */
+ reg8 = pci_read_config8(dev, DECODE_CONTROL_REG2);
+ reg8 |= BIOS_ROM_POSITIVE_DECODE;
+ pci_write_config8(dev, DECODE_CONTROL_REG2, reg8);
+}