Add initial support for the Intel 82810 northbridge.

Signed-off-by: Corey Osgood <corey.osgood@gmail.com>
Acked-by: Joseph Smith <joe@smittys.pointclark.net>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>



git-svn-id: svn://svn.coreboot.org/coreboot/trunk@2720 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

8 files changed, 801 insertions, 0 deletions

diff --git a/src/northbridge/intel/i82810/Config.lb b/src/northbridge/intel/i82810/Config.lb
new file mode 100644
index 0000000000..4701d5d336
--- /dev/null
+++ b/src/northbridge/intel/i82810/Config.lb
@@ -0,0 +1,22 @@
+##
+## This file is part of the LinuxBIOS project.
+##
+## Copyright (C) 2007 Corey Osgood <corey@slightlyhackish.com>
+##
+## 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
+##
+
+config chip.h
+object northbridge.o
diff --git a/src/northbridge/intel/i82810/chip.h b/src/northbridge/intel/i82810/chip.h
new file mode 100644
index 0000000000..6187fde469
--- /dev/null
+++ b/src/northbridge/intel/i82810/chip.h
@@ -0,0 +1,25 @@
+/*
+ * This file is part of the LinuxBIOS project.
+ *
+ * Copyright (C) 2007 Corey Osgood <corey@slightlyhackish.com>
+ *
+ * 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
+ */
+
+struct northbridge_intel_i82810_config
+{
+};
+
+extern struct chip_operations northbridge_intel_i82810_ops;
diff --git a/src/northbridge/intel/i82810/debug.c b/src/northbridge/intel/i82810/debug.c
new file mode 100644
index 0000000000..bcb60e2b0a
--- /dev/null
+++ b/src/northbridge/intel/i82810/debug.c
@@ -0,0 +1,35 @@
+
+static void dump_spd_registers(const struct mem_controller *ctrl)
+{
+	int i;
+	print_debug("\r\n");
+	for(i = 0; i < 4; i++) {
+		unsigned device;
+		device = ctrl->channel0[i];
+		if (device) {
+			int j;
+			print_debug("dimm: "); 
+			print_debug_hex8(i); 
+			print_debug(".0: ");
+			print_debug_hex8(device);
+			for(j = 0; j < 256; j++) {
+				int status;
+				unsigned char byte;
+				if ((j & 0xf) == 0) {
+					print_debug("\r\n");
+					print_debug_hex8(j);
+					print_debug(": ");
+				}
+				status = smbus_read_byte(device, j);
+				if (status < 0) {
+					print_debug("bad device\r\n");
+					break;
+				}
+				byte = status & 0xff;
+				print_debug_hex8(byte);
+				print_debug_char(' ');
+			}
+			print_debug("\r\n");
+		}
+	}
+}
diff --git a/src/northbridge/intel/i82810/i82810.h b/src/northbridge/intel/i82810/i82810.h
new file mode 100644
index 0000000000..0b406cead4
--- /dev/null
+++ b/src/northbridge/intel/i82810/i82810.h
@@ -0,0 +1,59 @@
+/*
+ * This file is part of the LinuxBIOS project.
+ *
+ * Copyright (C) 2007 Corey Osgood <corey@slightlyhackish.com>
+ *
+ * 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
+ */
+
+/*
+ * Datasheet:
+ *   - Name: Intel 810 Chipset:
+ *           82810/82810-DC100 Graphics and Memory Controller Hub (GMCH)
+ *   - URL: http://www.intel.com/design/chipsets/datashts/290656.htm
+ *   - PDF: ftp://download.intel.com/design/chipsets/datashts/29065602.pdf
+ *   - Order Number: 290656-002
+ */
+
+/*
+ * PCI Configuration Registers.
+ *
+ * Any addresses between 0x00 and 0xff not listed below are reserved and
+ * should not be touched.
+ */
+
+#define VID	0x00 /* Vendor Identification   */
+#define DID	0x02 /* Device Identification   */
+#define PCICMD	0x04 /* PCI Command Register    */
+#define PCISTS	0x06 /* PCI Status Register     */
+#define RID	0x08 /* Revision Identification */
+#define SUBC	0x0a /* Sub-Class Code          */
+#define BCC	0x0b /* Base Class Code         */
+#define MLT	0x0d /* Master Latency Timer    */
+#define HDR	0x0e /* Header Type             */
+#define SVID	0x2c /* Subsystem Vendor Identification  */
+#define SID	0x2e /* Subsystem Identification         */
+#define CAPPTR	0x34 /* Capabilities Pointer             */
+
+/* TODO: Descriptions  */
+#define GMCHCFG	0x50
+#define PAM	0x51
+#define DRP	0x52
+#define DRAMT	0x53
+#define FDHC	0x58
+#define SMRAM	0x70 /* System Management RAM Control */
+#define MISSC	0x72
+#define MISSC2	0x80
+#define BUFF_SC	0x92
diff --git a/src/northbridge/intel/i82810/northbridge.c b/src/northbridge/intel/i82810/northbridge.c
new file mode 100644
index 0000000000..9758be39f7
--- /dev/null
+++ b/src/northbridge/intel/i82810/northbridge.c
@@ -0,0 +1,217 @@
+/*
+ * This file is part of the LinuxBIOS project.
+ *
+ * Copyright (C) 2007 Corey Osgood <corey@slightlyhackish.com>
+ *
+ * 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 <console/console.h>
+#include <arch/io.h>
+#include <stdint.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+#include <stdlib.h>
+#include <string.h>
+#include <bitops.h>
+#include "chip.h"
+#include "northbridge.h"
+#include "i82810.h"
+
+static void northbridge_init(device_t dev) 
+{
+	printk_spew("Northbridge init\n");
+}
+
+static struct device_operations northbridge_operations = {
+	.read_resources   = pci_dev_read_resources,
+	.set_resources    = pci_dev_set_resources,
+	.enable_resources = pci_dev_enable_resources,
+	.init             = northbridge_init,
+	.enable           = 0,
+	.ops_pci          = 0,
+};
+
+static struct pci_driver northbridge_driver __pci_driver = {
+	.ops = &northbridge_operations,
+	.vendor = PCI_VENDOR_ID_INTEL,
+	.device = 0x7120,
+};
+
+#define BRIDGE_IO_MASK (IORESOURCE_IO | IORESOURCE_MEM)
+
+static void pci_domain_read_resources(device_t dev)
+{
+	struct resource *resource;
+	unsigned reg;
+
+	/* Initialize the system wide io space constraints */
+	resource = new_resource(dev, IOINDEX_SUBTRACTIVE(0, 0));
+	resource->base = 0x400;
+	resource->limit = 0xffffUL;
+	resource->flags = IORESOURCE_IO | IORESOURCE_SUBTRACTIVE | IORESOURCE_ASSIGNED;
+
+	/* Initialize the system wide memory resources constraints */
+	resource = new_resource(dev, IOINDEX_SUBTRACTIVE(1, 0));
+	resource->limit = 0xffffffffULL;
+	resource->flags = IORESOURCE_MEM | IORESOURCE_SUBTRACTIVE | IORESOURCE_ASSIGNED;
+}
+
+static void ram_resource(device_t dev, unsigned long index,
+        unsigned long basek, unsigned long sizek)
+{
+	struct resource *resource;
+
+	if (!sizek) {
+		return;
+	}
+	resource = new_resource(dev, index);
+	resource->base  = ((resource_t)basek) << 10;
+	resource->size  = ((resource_t)sizek) << 10;
+	resource->flags =  IORESOURCE_MEM | IORESOURCE_CACHEABLE | \
+		IORESOURCE_FIXED | IORESOURCE_STORED | IORESOURCE_ASSIGNED;
+}
+
+static void tolm_test(void *gp, struct device *dev, struct resource *new)
+{
+	struct resource **best_p = gp;
+	struct resource *best;
+	best = *best_p;
+	if (!best || (best->base > new->base)) {
+		best = new;
+	}
+	*best_p = best;
+}
+
+static uint32_t find_pci_tolm(struct bus *bus)
+{
+	struct resource *min;
+	uint32_t tolm;
+	min = 0;
+	search_bus_resources(bus, IORESOURCE_MEM, IORESOURCE_MEM, tolm_test, &min);
+	tolm = 0xffffffffUL;
+	if (min && tolm > min->base) {
+		tolm = min->base;
+	}
+	return tolm;
+}
+
+/* Table which returns the RAM size in MB when fed the DRP[7:4] or [3:0] value.
+ * Note that 2 is a value which the DRP should never be programmed to.
+ * Some size values appear twice, due to single-sided vs dual-sided banks.
+ */
+static int translate_i82810_to_mb[] = {
+/* DRP	0  1 (2) 3   4   5   6   7   8   9   A   B   C    D    E    F */
+/* MB */0, 8, 0, 16, 16, 24, 32, 32, 48, 64, 64, 96, 128, 128, 192, 256,
+};
+
+static void pci_domain_set_resources(device_t dev)
+{
+	device_t mc_dev;
+	uint32_t pci_tolm;
+
+	pci_tolm = find_pci_tolm(&dev->link[0]);
+	mc_dev = dev->link[0].children;
+
+	if (mc_dev) {
+		/* Figure out which areas are/should be occupied by RAM.
+		 * This is all computed in kilobytes and converted to/from
+		 * the memory controller right at the edges.
+		 * Having different variables in different units is
+		 * too confusing to get right.  Kilobytes are good up to
+		 * 4 Terabytes of RAM...
+		 */
+		unsigned long tomk, tolmk;
+		int idx;
+		int drp_value;
+
+		/* First get the value for DIMM 0. */
+		drp_value = pci_read_config8(mc_dev, DRP);
+		/* Translate it to MB and add to tomk. */
+		tomk = (unsigned long)(translate_i82810_to_mb[drp_value & 0xf]);
+		/* Now do the same for DIMM 1. */
+		drp_value = drp_value >> 4; // >>= 4; //? mess with later
+		tomk += (unsigned long)(translate_i82810_to_mb[drp_value]);
+
+		printk_debug("Setting RAM size to %d MB\n", tomk);
+
+		/* Convert tomk from MB to KB. */
+		tomk = tomk << 10;
+
+		/* Compute the top of Low memory. */
+		tolmk = pci_tolm >> 10;
+		if (tolmk >= tomk) {
+			/* The PCI hole does does not overlap the memory. */
+			tolmk = tomk;
+		}
+
+		/* Report the memory regions. */
+		idx = 10;
+		ram_resource(dev, idx++, 0, 640);
+		ram_resource(dev, idx++, 1024, tolmk - 1024);
+	}
+	assign_resources(&dev->link[0]);
+}
+
+static unsigned int pci_domain_scan_bus(device_t dev, unsigned int max)
+{
+	max = pci_scan_bus(&dev->link[0], PCI_DEVFN(0, 0), 0xff, max);
+	return max;
+}
+
+static struct device_operations pci_domain_ops = {
+	.read_resources   = pci_domain_read_resources,
+	.set_resources    = pci_domain_set_resources,
+	.enable_resources = enable_childrens_resources,
+	.init             = 0,
+	.scan_bus         = pci_domain_scan_bus,
+};
+
+static void cpu_bus_init(device_t dev)
+{
+	initialize_cpus(&dev->link[0]);
+}
+
+static void cpu_bus_noop(device_t dev)
+{
+}
+
+static struct device_operations cpu_bus_ops = {
+	.read_resources   = cpu_bus_noop,
+	.set_resources    = cpu_bus_noop,
+	.enable_resources = cpu_bus_noop,
+	.init             = cpu_bus_init,
+	.scan_bus         = 0,
+};
+
+static void enable_dev(struct device *dev)
+{
+	struct device_path path;
+
+	/* Set the operations if it is a special bus type */
+	if (dev->path.type == DEVICE_PATH_PCI_DOMAIN) {
+		dev->ops = &pci_domain_ops;
+		pci_set_method(dev);
+	}
+	else if (dev->path.type == DEVICE_PATH_APIC_CLUSTER) {
+		dev->ops = &cpu_bus_ops;
+	}
+}
+
+struct chip_operations northbridge_intel_i82810_ops = {
+	CHIP_NAME("Intel 82810 Northbridge")
+	.enable_dev = enable_dev,
+};
diff --git a/src/northbridge/intel/i82810/northbridge.h b/src/northbridge/intel/i82810/northbridge.h
new file mode 100644
index 0000000000..43db8395e5
--- /dev/null
+++ b/src/northbridge/intel/i82810/northbridge.h
@@ -0,0 +1,26 @@
+/*
+ * This file is part of the LinuxBIOS project.
+ *
+ * Copyright (C) 2007 Corey Osgood <corey@slightlyhackish.com>
+ *
+ * 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
+ */
+
+#ifndef NORTHBRIDGE_INTEL_I82810_NORTHBRIDGE_H
+#define NORTHBRIDGE_INTEL_I82810_NORTHBRIDGE_H
+
+extern unsigned int i82810_scan_root_bus(device_t root, unsigned int max);
+
+#endif				/* NORTHBRIDGE_INTEL_I82810_NORTHBRIDGE_H */
diff --git a/src/northbridge/intel/i82810/raminit.c b/src/northbridge/intel/i82810/raminit.c
new file mode 100644
index 0000000000..55102dbba6
--- /dev/null
+++ b/src/northbridge/intel/i82810/raminit.c
@@ -0,0 +1,327 @@
+/*
+ * This file is part of the LinuxBIOS project.
+ *
+ * Copyright (C) 2007 Uwe Hermann <uwe@hermann-uwe.de>
+ * Copyright (C) 2007 Corey Osgood <corey@slightlyhackish.com>
+ *
+ * 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 <spd.h>
+#include <sdram_mode.h>
+#include <delay.h>
+#include "i82810.h"
+
+/*-----------------------------------------------------------------------------
+Macros and definitions.
+-----------------------------------------------------------------------------*/
+
+/* Uncomment this to enable debugging output. */
+// #define DEBUG_RAM_SETUP 1
+
+/* Debugging macros. */
+#if defined(DEBUG_RAM_SETUP)
+#define PRINT_DEBUG(x)		print_debug(x)
+#define PRINT_DEBUG_HEX8(x)	print_debug_hex8(x)
+#define PRINT_DEBUG_HEX16(x)	print_debug_hex16(x)
+#define PRINT_DEBUG_HEX32(x)	print_debug_hex32(x)
+#define DUMPNORTH()		dump_pci_device(PCI_DEV(0, 0, 0))
+#else
+#define PRINT_DEBUG(x)
+#define PRINT_DEBUG_HEX8(x)
+#define PRINT_DEBUG_HEX16(x)
+#define PRINT_DEBUG_HEX32(x)
+#define DUMPNORTH()
+#endif
+
+/* DRAMT[7:5] - SDRAM Mode Select (SMS). */
+#define RAM_COMMAND_SELF_REFRESH 0x0 /* IE disable refresh */
+#define RAM_COMMAND_NORMAL	 0x1 /* Normal refresh, 15.6us/11.7us for 100/133MHz */
+#define RAM_COMMAND_NORMAL_FR	 0x2 /* Fast refresh, 7.8us/5.85us for 100/133MHz */
+#define RAM_COMMAND_NOP		 0x4
+#define RAM_COMMAND_PRECHARGE	 0x5
+#define RAM_COMMAND_MRS		 0x6
+#define RAM_COMMAND_CBR		 0x7
+
+/*-----------------------------------------------------------------------------
+SDRAM configuration functions.
+-----------------------------------------------------------------------------*/
+
+/**
+ * Send the specified RAM command to all DIMMs.
+ *
+ * @param Memory controller
+ * @param TODO
+ * @param TODO
+ */
+static void do_ram_command(const struct mem_controller *ctrl, uint32_t command,
+			   uint32_t addr_offset, uint32_t row_offset)
+{
+	int i;
+	uint8_t reg;
+
+	/* TODO: Support for multiple DIMMs. */
+
+	/* Configure the RAM command. */
+	reg = pci_read_config8(ctrl->d0, DRAMT);
+	reg &= 0x1f;		/* Clear bits 7-5. */
+	reg |= command << 5;
+	pci_write_config8(ctrl->d0, DRAMT, reg);
+
+	/* RAM_COMMAND_NORMAL affects only the memory controller and
+	   doesn't need to be "sent" to the DIMMs. */
+	/* if (command == RAM_COMMAND_NORMAL) return; */
+
+	PRINT_DEBUG("    Sending RAM command 0x");
+	PRINT_DEBUG_HEX8(reg);
+	PRINT_DEBUG(" to 0x");
+	PRINT_DEBUG_HEX32(0 + addr_offset); // FIXME
+	PRINT_DEBUG("\r\n");
+
+	/* Read from (DIMM start address + addr_offset). */
+	read32(0 + addr_offset);	//first offset is always 0
+	read32(row_offset + addr_offset);
+}
+
+/*-----------------------------------------------------------------------------
+DIMM-independant configuration functions.
+-----------------------------------------------------------------------------*/
+
+static void spd_set_dram_size(const struct mem_controller *ctrl, uint32_t row_offset)
+{
+	/* The variables drp and dimm_size have to be ints since all the
+	 * SMBus-related functions return ints, and its just easier this way.
+	 */
+	int i, drp, dimm_size;
+
+	drp = 0x00;
+	
+	for (i = 0; i < DIMM_SOCKETS; i++)
+	{
+		/* First check if a DIMM is actually present. */
+		if (smbus_read_byte(ctrl->channel0[i], 2) == 4) {
+			print_debug("Found DIMM in slot ");
+			print_debug_hex8(i);
+			print_debug("\r\n");
+
+			dimm_size = smbus_read_byte(ctrl->channel0[i], 31);
+
+			/* WISHLIST: would be nice to display it as decimal? */
+			print_debug("DIMM is 0x");
+			print_debug_hex8(dimm_size * 4);
+			print_debug("MB\r\n");
+
+			/* The i810 can't handle DIMMs larger than 128MB per
+			 * side. This will fail if the DIMM uses a
+			 * non-supported DRAM tech, and can't be used until
+			 * buffers are done dynamically.
+			 * Note: the factory BIOS just dies if it spots
+			 * this :D
+			 */
+			if(dimm_size > 32) {
+				print_err("DIMM row sizes larger than 128MB not" 
+							"supported on i810\r\n");
+				print_err("Attempting to treat as 128MB DIMM\r\n");
+				dimm_size = 32;
+			}
+
+			/* Set the row offset, in KBytes (should this be Kbits?) */
+			/* Note that this offset is the start of the next row. */
+			row_offset = (dimm_size * 4 * 1024);
+
+			/* This is the way I was doing this, it's provided mainly
+			 * as an alternative to the "new" way.
+			 */
+
+			#if 0
+			/* 8MB */
+			if(dimm_size == 0x2) dimm_size = 0x1;
+			/* 16MB */
+			else if(dimm_size == 0x4) dimm_size = 0x4;
+			/* 32MB */
+			else if(dimm_size == 0x8) dimm_size = 0x7;
+			/* 64 MB */
+			else if(dimm_size == 0x10) dimm_size = 0xa;
+			/* 128 MB */
+			else if(dimm_size == 0x20) dimm_size = 0xd;
+			else print_debug("Ram Size not supported\r\n");
+			#endif
+
+			/* This array is provided in raminit.h, because it got
+			 * extremely messy. The above way is cleaner, but
+			 * doesn't support any asymetrical/odd configurations.
+			 */
+			dimm_size = translate_spd_to_i82810[dimm_size];
+
+			print_debug("After translation, dimm_size is 0x");
+			print_debug_hex8(dimm_size);
+			print_debug("\r\n");
+
+			/* If the DIMM is dual-sided, the DRP value is +2 */
+			/* TODO: Figure out asymetrical configurations */
+			if ((smbus_read_byte(ctrl->channel0[i], 127) | 0xf) == 0xff) {
+				print_debug("DIMM is dual-sided\r\n");
+				dimm_size += 2;
+			}
+		} else {
+			print_debug("No DIMM found in slot ");
+			print_debug_hex8(i);
+			print_debug("\r\n");
+
+			/* If there's no DIMM in the slot, set the value to 0. */
+			dimm_size = 0x00;
+		}
+
+		/* Put in dimm_size to reflect the current DIMM. */
+		drp |= dimm_size << (i * 4);
+	}
+
+	print_debug("DRP calculated to 0x");
+	print_debug_hex8(drp);
+	print_debug("\r\n");
+
+	pci_write_config8(ctrl->d0, DRP, drp);
+}
+
+static void set_dram_timing(const struct mem_controller *ctrl)
+{
+	/* TODO, for now using default, hopefully safe values. */
+	// pci_write_config8(ctrl->d0, DRAMT, 0x00);
+}
+
+static void set_dram_buffer_strength(const struct mem_controller *ctrl)
+{
+	/* TODO: This needs to be set according to the DRAM tech
+	 * (x8, x16, or x32). Argh, Intel provides no docs on this!
+	 * Currently, it needs to be pulled from the output of
+	 * lspci -xxx Rx92
+	 */
+	pci_write_config16(ctrl->d0, BUFF_SC, 0x77da);
+}
+
+/*-----------------------------------------------------------------------------
+Public interface.
+-----------------------------------------------------------------------------*/
+
+/**
+ * TODO.
+ *
+ * @param Memory controller
+ */
+static void sdram_set_registers(const struct mem_controller *ctrl)
+{
+	unsigned long val;
+
+	/* TODO */
+	pci_write_config8(ctrl->d0, GMCHCFG, 0x60);
+
+	/* PAMR: Programmable Attributes Register
+	 * Every pair of bits controls an address range:
+	 * 00 = Disabled, all accesses are forwarded to the ICH
+	 * 01 = Read Only
+	 * 10 = Write Only
+	 * 11 = Read/Write
+
+	 * Bit	Range
+	 * 7:6	000F0000 - 000FFFFF
+	 * 5:4	000E0000 - 000EFFFF
+	 * 3:2	000D0000 - 000DFFFF
+	 * 1:0	000C0000 - 000CFFFF
+	 */
+
+	/* Ideally, this should be R/W for as many ranges as possible. */
+	pci_write_config8(ctrl->d0, PAM, 0x00);
+
+	/* Enable 1MB framebuffer. */
+	pci_write_config8(ctrl->d0, SMRAM, 0xC0);
+
+	val = pci_read_config16(ctrl->d0, MISSC);
+	/* Preserve reserved bits. */
+	val &= 0xff06;
+	/* Set graphics cache window to 32MB, no power throttling. */
+	val |= 0x0001;
+	pci_write_config16(ctrl->d0, MISSC, val);
+
+	val = pci_read_config8(ctrl->d0, MISSC2);
+	/* Enable graphics palettes and clock gating (not optional!) */
+	val |= 0x06;
+	pci_write_config8(ctrl->d0, MISSC2, val);
+}
+
+/**
+ * TODO.
+ *
+ * @param Memory controller
+ */
+static void sdram_set_spd_registers(const struct mem_controller *ctrl)
+{
+	/* spd_set_dram_size() moved into sdram_enable() to prevent having
+	 * to pass a variable between here and there.
+	 */
+	set_dram_buffer_strength(ctrl);
+
+	set_dram_timing(ctrl);
+}
+
+/**
+ * Enable SDRAM.
+ *
+ * @param Number of controllers
+ * @param Memory controller
+ */
+static void sdram_enable(int controllers, const struct mem_controller *ctrl)
+{
+	int i;
+
+	/* Todo: this will currently work with either one dual sided or two
+	 * single sided DIMMs. Needs to work with 2 dual sided DIMMs in the
+	 * long run.
+	 */
+	uint32_t row_offset;
+
+	spd_set_dram_size(ctrl, row_offset); 
+
+	/* 1. Apply NOP. */
+	PRINT_DEBUG("RAM Enable 1: Apply NOP\r\n");
+	do_ram_command(ctrl, RAM_COMMAND_NOP, 0, row_offset);
+	udelay(200);
+
+	/* 2. Precharge all. Wait tRP. */
+	PRINT_DEBUG("RAM Enable 2: Precharge all\r\n");
+	do_ram_command(ctrl, RAM_COMMAND_PRECHARGE, 0, row_offset);
+	udelay(1);
+
+	/* 3. Perform 8 refresh cycles. Wait tRC each time. */
+	PRINT_DEBUG("RAM Enable 3: CBR\r\n");
+	do_ram_command(ctrl, RAM_COMMAND_CBR, 0, row_offset);
+	for (i = 0; i < 8; i++) {
+		read32(0);
+		read32(row_offset);
+		udelay(1);
+	}
+
+	/* 4. Mode register set. Wait two memory cycles. */
+	PRINT_DEBUG("RAM Enable 4: Mode register set\r\n");
+	do_ram_command(ctrl, RAM_COMMAND_MRS, 0x1d0, row_offset);
+	udelay(2);
+
+	/* 5. Normal operation (enables refresh) */
+	PRINT_DEBUG("RAM Enable 5: Normal operation\r\n");
+	do_ram_command(ctrl, RAM_COMMAND_NORMAL, 0, row_offset);
+	udelay(1);
+
+	PRINT_DEBUG("Northbridge following SDRAM init:\r\n");
+	DUMPNORTH();
+}
diff --git a/src/northbridge/intel/i82810/raminit.h b/src/northbridge/intel/i82810/raminit.h
new file mode 100644
index 0000000000..43edd837d6
--- /dev/null
+++ b/src/northbridge/intel/i82810/raminit.h
@@ -0,0 +1,90 @@
+/*
+ * This file is part of the LinuxBIOS project.
+ *
+ * Copyright (C) 2007 Corey Osgood <corey@slightlyhackish.com>
+ *
+ * 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
+ */
+
+#ifndef NORTHBRIDGE_INTEL_I82810_RAMINIT_H
+#define NORTHBRIDGE_INTEL_I82810_RAMINIT_H
+
+/* The i810 supports max 2 dual-sided DIMMs. */
+#define DIMM_SOCKETS	2
+
+struct mem_controller {
+	device_t d0;
+	uint16_t channel0[DIMM_SOCKETS];
+};
+
+
+#endif				/* NORTHBRIDGE_INTEL_I82810_RAMINIT_H */
+
+/* The following table has been bumped over to this header to avoid clutter in 
+ * raminit.c. It's used to translate the value read from SPD Byte 31 to a value
+ * the northbridge can understand in DRP, aka Rx52[7:4], [3:0]. Where most
+ * northbridges have some sort of simple calculation that can be done for this,
+ * I haven't yet figured out one for this northbridge. Until someone does,
+ * this table is necessary.
+ */
+
+/* TODO: Find a better way of doing this */
+
+static const uint8_t translate_spd_to_i82810[] = {
+	/* Note: 4MB sizes are not supported, so dual-sided DIMMs with a 4MB 
+	 * side can't be either, at least for now.
+	 */
+	/* TODO: For above case, only use the other side if > 4MB, and get some
+	 * of these DIMMs to test it with. Same for unsupported 128/x sizes.
+	 */
+
+		/*   SPD Byte 31	Memory Size [Side 1/2]	*/
+	0xff,	/*	0x01		No memory	*/
+	0xff,	/*	0x01		 4/0		*/
+	0x01,	/*	0x02		 8/0		*/
+	0xff,	/*	0x03		 8/4		*/
+	0x04,	/*	0x04		16/0 or 16	*/
+	0xff,	/*	0x05		16/4		*/
+	0x05,	/*	0x06		16/8		*/
+	0xff,	/*	0x07		Invalid		*/
+	0x07,	/*	0x08		32/0 or 32	*/
+	0xff,	/*	0x09		32/4		*/
+	0xff,	/*	0x0A		32/8		*/
+	0xff,	/*	0x0B		Invalid		*/
+	0x08,	/*	0x0C		32/16		*/
+	0xff, 0xff, 0xff, /* 0x0D-0F	Invalid		*/
+	0x0a,	/*	0x10		64/0 or 64	*/
+	0xff,	/*	0x11		64/4		*/
+	0xff,	/*	0x12		64/8		*/
+	0xff,	/*	0x13		Invalid		*/
+	0xff,	/*	0x14		64/16		*/
+	0xff, 0xff, 0xff, /* 0x15-17	Invalid		*/
+	0x0b,	/*	0x18		64/32		*/
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0x19-1f Invalid */
+	0x0d,	/*	0x20		128/0 or 128	*/
+	/* These configurations are not supported by the i810 */
+	0xff,	/*	0x21		128/4		*/
+	0xff,	/*	0x22		128/8		*/
+	0xff,	/*	0x23		Invalid		*/
+	0xff,	/*	0x24		128/16		*/
+	0xff, 0xff, 0xff, /* 0x25-27	Invalid		*/
+	0xff,	/*	0x28		128/32		*/
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, /* 0x29-2f Invalid */
+	0x0e,	/*	0x30		128/64		*/
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, /* 0x31-3f	Invalid		*/
+	0x0f,	/*	0x40		256/0 or 256	*/
+	/* Anything larger is not supported by the i810 */
+};