src/northbridge/intel/i945/early_init.c

/* SPDX-License-Identifier: GPL-2.0-only */

#include <cbmem.h>
#include <cf9_reset.h>
#include <console/console.h>
#include <device/pci_def.h>
#include <device/pci_ops.h>
#include <device/pci.h>
#include <option.h>
#include <romstage_handoff.h>
#include <types.h>

#include "i945.h"

int i945_silicon_revision(void)
{
	return pci_read_config8(HOST_BRIDGE, PCI_CLASS_REVISION);
}

static void i945m_detect_chipset(void)
{
	u8 reg8;

	printk(BIOS_INFO, "\n");
	reg8 = (pci_read_config8(HOST_BRIDGE, 0xe7) & 0x70) >> 4;
	switch (reg8) {
	case 1:
		printk(BIOS_INFO, "Mobile Intel(R) 82945GM/GME Express");
		break;
	case 2:
		printk(BIOS_INFO, "Mobile Intel(R) 82945GMS/GU/GSE Express");
		break;
	case 3:
		printk(BIOS_INFO, "Mobile Intel(R) 82945PM Express");
		break;
	case 5:
		printk(BIOS_INFO, "Intel(R) 82945GT Express");
		break;
	case 6:
		printk(BIOS_INFO, "Mobile Intel(R) 82943/82940GML Express");
		break;
	default: /* Others reserved. */
		printk(BIOS_INFO, "Unknown (%02x)", reg8);
	}
	printk(BIOS_INFO, " Chipset\n");

	printk(BIOS_DEBUG, "(G)MCH capable of up to FSB ");
	reg8 = (pci_read_config8(HOST_BRIDGE, 0xe3) & 0xe0) >> 5;
	switch (reg8) {
	case 2:
		printk(BIOS_DEBUG, "800 MHz"); /* According to 965 spec */
		break;
	case 3:
		printk(BIOS_DEBUG, "667 MHz");
		break;
	case 4:
		printk(BIOS_DEBUG, "533 MHz");
		break;
	default:
		printk(BIOS_DEBUG, "N/A MHz (%02x)", reg8);
	}
	printk(BIOS_DEBUG, "\n");

	printk(BIOS_DEBUG, "(G)MCH capable of ");
	reg8 = (pci_read_config8(HOST_BRIDGE, 0xe4) & 0x07);
	switch (reg8) {
	case 2:
		printk(BIOS_DEBUG, "up to DDR2-667");
		break;
	case 3:
		printk(BIOS_DEBUG, "up to DDR2-533");
		break;
	case 4:
		printk(BIOS_DEBUG, "DDR2-400");
		break;
	default: /* Others reserved. */
		printk(BIOS_INFO, "unknown max. RAM clock (%02x).", reg8);
	}
	printk(BIOS_DEBUG, "\n");

	if (CONFIG(NORTHBRIDGE_INTEL_SUBTYPE_I945GC))
		printk(BIOS_ERR, "coreboot is compiled for the wrong chipset.\n");
}

static void i945_detect_chipset(void)
{
	u8 reg8;

	printk(BIOS_INFO, "\nIntel(R) ");

	reg8 = ((pci_read_config8(HOST_BRIDGE, 0xe7) >> 5) & 4)
	     | ((pci_read_config8(HOST_BRIDGE, 0xe4) >> 4) & 3);
	switch (reg8) {
	case 0:
	case 1:
		printk(BIOS_INFO, "82945G");
		break;
	case 2:
	case 3:
		printk(BIOS_INFO, "82945P");
		break;
	case 4:
		printk(BIOS_INFO, "82945GC");
		break;
	case 5:
		printk(BIOS_INFO, "82945GZ");
		break;
	case 6:
	case 7:
		printk(BIOS_INFO, "82945PL");
		break;
	default:
		break;
	}
	printk(BIOS_INFO, " Chipset\n");

	printk(BIOS_DEBUG, "(G)MCH capable of ");
	reg8 = (pci_read_config8(HOST_BRIDGE, 0xe4) & 0x07);
	switch (reg8) {
	case 0:
	case 2:
		printk(BIOS_DEBUG, "up to DDR2-667");
		break;
	case 3:
		printk(BIOS_DEBUG, "up to DDR2-533");
		break;
	default: /* Others reserved. */
		printk(BIOS_INFO, "unknown max. RAM clock (%02x).", reg8);
	}
	printk(BIOS_DEBUG, "\n");

	if (CONFIG(NORTHBRIDGE_INTEL_SUBTYPE_I945GM))
		printk(BIOS_ERR, "coreboot is compiled for the wrong chipset.\n");
}

static void i945_setup_bars(void)
{
	u8 reg8, gfxsize;

	/* As of now, we don't have all the A0 workarounds implemented */
	if (i945_silicon_revision() == 0)
		printk(BIOS_INFO, "Warning: i945 silicon revision A0 might not work correctly.\n");

	printk(BIOS_DEBUG, "Setting up static northbridge registers...");
	/* Set up all hardcoded northbridge BARs */
	pci_write_config32(HOST_BRIDGE, EPBAR,  CONFIG_FIXED_EPBAR_MMIO_BASE  | 1);
	pci_write_config32(HOST_BRIDGE, MCHBAR, CONFIG_FIXED_MCHBAR_MMIO_BASE | 1);
	pci_write_config32(HOST_BRIDGE, DMIBAR, CONFIG_FIXED_DMIBAR_MMIO_BASE | 1);
	pci_write_config32(HOST_BRIDGE, X60BAR, DEFAULT_X60BAR | 1);

	/* vram size from CMOS option */
	gfxsize = get_uint_option("gfx_uma_size", 2);	/* 2 for 8MB */
	/* make sure no invalid setting is used */
	if (gfxsize > 6)
		gfxsize = 2;
	pci_write_config16(HOST_BRIDGE, GGC, ((gfxsize + 1) << 4));
	/* TSEG 2M, This amount can easily be covered by SMRR MTRR's,
	   which requires to have TSEG_BASE aligned to TSEG_SIZE. */
	pci_update_config8(HOST_BRIDGE, ESMRAMC, ~0x07, (1 << 1) | (1 << 0));

	/* Set C0000-FFFFF to access RAM on both reads and writes */
	pci_write_config8(HOST_BRIDGE, PAM0, 0x30);
	pci_write_config8(HOST_BRIDGE, PAM1, 0x33);
	pci_write_config8(HOST_BRIDGE, PAM2, 0x33);
	pci_write_config8(HOST_BRIDGE, PAM3, 0x33);
	pci_write_config8(HOST_BRIDGE, PAM4, 0x33);
	pci_write_config8(HOST_BRIDGE, PAM5, 0x33);
	pci_write_config8(HOST_BRIDGE, PAM6, 0x33);

	printk(BIOS_DEBUG, " done.\n");

	/* Wait for MCH BAR to come up */
	printk(BIOS_DEBUG, "Waiting for MCHBAR to come up...");
	if ((pci_read_config32(HOST_BRIDGE, 0xe4) & 0x20000) == 0x00) { /* Bit 49 of CAPID0 */
		do {
			reg8 = *(volatile u8 *)0xfed40000;
		} while (!(reg8 & 0x80));
	}
	printk(BIOS_DEBUG, "ok\n");
}

static void i945_setup_egress_port(void)
{
	u32 reg32;
	u32 timeout;

	printk(BIOS_DEBUG, "Setting up Egress Port RCRB\n");

	/* Egress Port Virtual Channel 0 Configuration */

	/* map only TC0 to VC0 */
	reg32 = epbar_read32(EPVC0RCTL);
	reg32 &= 0xffffff01;
	epbar_write32(EPVC0RCTL, reg32);

	reg32 = epbar_read32(EPPVCCAP1);
	reg32 &= ~(7 << 0);
	reg32 |= 1;
	epbar_write32(EPPVCCAP1, reg32);

	/* Egress Port Virtual Channel 1 Configuration */
	reg32 = epbar_read32(0x2c);
	reg32 &= 0xffffff00;
	if (CONFIG(NORTHBRIDGE_INTEL_SUBTYPE_I945GC)) {
		if ((mchbar_read32(CLKCFG) & 7) == 0)
			reg32 |= 0x1a;	/* 1067MHz */
	}
	if ((mchbar_read32(CLKCFG) & 7) == 1)
		reg32 |= 0x0d;	/* 533MHz */
	if ((mchbar_read32(CLKCFG) & 7) == 2)
		reg32 |= 0x14;	/* 800MHz */
	if ((mchbar_read32(CLKCFG) & 7) == 3)
		reg32 |= 0x10;	/* 667MHz */
	epbar_write32(0x2c, reg32);

	epbar_write32(EPVC1MTS, 0x0a0a0a0a);

	reg32 = epbar_read32(EPVC1RCAP);
	reg32 &= ~(0x7f << 16);
	reg32 |= (0x0a << 16);
	epbar_write32(EPVC1RCAP, reg32);

	if (CONFIG(NORTHBRIDGE_INTEL_SUBTYPE_I945GC)) {
		if ((mchbar_read32(CLKCFG) & 7) == 0) {	/* 1067MHz */
			epbar_write32(EPVC1IST + 0, 0x01380138);
			epbar_write32(EPVC1IST + 4, 0x01380138);
		}
	}

	if ((mchbar_read32(CLKCFG) & 7) == 1) {	/* 533MHz */
		epbar_write32(EPVC1IST + 0, 0x009c009c);
		epbar_write32(EPVC1IST + 4, 0x009c009c);
	}

	if ((mchbar_read32(CLKCFG) & 7) == 2) {	/* 800MHz */
		epbar_write32(EPVC1IST + 0, 0x00f000f0);
		epbar_write32(EPVC1IST + 4, 0x00f000f0);
	}

	if ((mchbar_read32(CLKCFG) & 7) == 3) {	/* 667MHz */
		epbar_write32(EPVC1IST + 0, 0x00c000c0);
		epbar_write32(EPVC1IST + 4, 0x00c000c0);
	}

	/* Is internal graphics enabled? */
	if (pci_read_config8(HOST_BRIDGE, DEVEN) & (DEVEN_D2F0 | DEVEN_D2F1))
		mchbar_setbits32(MMARB1, 1 << 17);

	/* Assign Virtual Channel ID 1 to VC1 */
	reg32 = epbar_read32(EPVC1RCTL);
	reg32 &= ~(7 << 24);
	reg32 |= (1 << 24);
	epbar_write32(EPVC1RCTL, reg32);

	reg32 = epbar_read32(EPVC1RCTL);
	reg32 &= 0xffffff01;
	reg32 |= (1 << 7);
	epbar_write32(EPVC1RCTL, reg32);

	epbar_write32(PORTARB + 0x00, 0x01000001);
	epbar_write32(PORTARB + 0x04, 0x00040000);
	epbar_write32(PORTARB + 0x08, 0x00001000);
	epbar_write32(PORTARB + 0x0c, 0x00000040);
	epbar_write32(PORTARB + 0x10, 0x01000001);
	epbar_write32(PORTARB + 0x14, 0x00040000);
	epbar_write32(PORTARB + 0x18, 0x00001000);
	epbar_write32(PORTARB + 0x1c, 0x00000040);

	epbar_setbits32(EPVC1RCTL, 1 << 16);
	epbar_setbits32(EPVC1RCTL, 1 << 16);

	printk(BIOS_DEBUG, "Loading port arbitration table ...");
	/* Loop until bit 0 becomes 0 */
	timeout = 0x7fffff;
	while ((epbar_read16(EPVC1RSTS) & (1 << 0)) && --timeout)
		;
	if (!timeout)
		printk(BIOS_DEBUG, "timeout!\n");
	else
		printk(BIOS_DEBUG, "ok\n");

	/* Now enable VC1 */
	epbar_setbits32(EPVC1RCTL, 1 << 31);

	printk(BIOS_DEBUG, "Wait for VC1 negotiation ...");
	/* Wait for VC1 negotiation pending */
	timeout = 0x7fff;
	while ((epbar_read16(EPVC1RSTS) & (1 << 1)) && --timeout)
		;
	if (!timeout)
		printk(BIOS_DEBUG, "timeout!\n");
	else
		printk(BIOS_DEBUG, "ok\n");

}

static void ich7_setup_dmi_rcrb(void)
{
	u16 reg16;
	u32 reg32;

	reg16 = RCBA16(LCTL);
	reg16 &= ~(3 << 0);
	reg16 |= 3;
	RCBA16(LCTL) = reg16;

	RCBA32(V0CTL) = 0x80000001;
	RCBA32(V1CAP) = 0x03128010;

	pci_write_config16(PCI_DEV(0, 0x1c, 0), 0x42, 0x0141);
	pci_write_config16(PCI_DEV(0, 0x1c, 4), 0x42, 0x0141);
	pci_write_config16(PCI_DEV(0, 0x1c, 5), 0x42, 0x0141);

	pci_write_config32(PCI_DEV(0, 0x1c, 4), 0x54, 0x00480ce0);
	pci_write_config32(PCI_DEV(0, 0x1c, 5), 0x54, 0x00500ce0);

	reg32 = RCBA32(V1CTL);
	reg32 &= ~((0x7f << 1) | (7 << 17) | (7 << 24));
	reg32 |= (0x40 << 1) | (4 << 17) | (1 << 24) | (1 << 31);
	RCBA32(V1CTL) = reg32;

	RCBA32(LCAP) |= (3 << 10);
}

static void i945_setup_dmi_rcrb(void)
{
	u32 reg32;
	u32 timeout;
	int activate_aspm = 1; /* hardcode ASPM for now */

	printk(BIOS_DEBUG, "Setting up DMI RCRB\n");

	/* Virtual Channel 0 Configuration */
	reg32 = dmibar_read32(DMIVC0RCTL0);
	reg32 &= 0xffffff01;
	dmibar_write32(DMIVC0RCTL0, reg32);

	reg32 = dmibar_read32(DMIPVCCAP1);
	reg32 &= ~(7 << 0);
	reg32 |= 1;
	dmibar_write32(DMIPVCCAP1, reg32);

	reg32 = dmibar_read32(DMIVC1RCTL);
	reg32 &= ~(7 << 24);
	reg32 |= (1 << 24);	/* NOTE: This ID must match ICH7 side */
	dmibar_write32(DMIVC1RCTL, reg32);

	reg32 = dmibar_read32(DMIVC1RCTL);
	reg32 &= 0xffffff01;
	reg32 |= (1 << 7);
	dmibar_write32(DMIVC1RCTL, reg32);

	/* Now enable VC1 */
	dmibar_setbits32(DMIVC1RCTL, 1 << 31);

	printk(BIOS_DEBUG, "Wait for VC1 negotiation ...");
	/* Wait for VC1 negotiation pending */
	timeout = 0x7ffff;
	while ((dmibar_read16(DMIVC1RSTS) & (1 << 1)) && --timeout)
		;
	if (!timeout)
		printk(BIOS_DEBUG, "timeout!\n");
	else
		printk(BIOS_DEBUG, "done..\n");

	/* Enable Active State Power Management (ASPM) L0 state */

	reg32 = dmibar_read32(DMILCAP);
	reg32 &= ~(7 << 12);
	reg32 |= (2 << 12);

	reg32 &= ~(7 << 15);

	reg32 |= (2 << 15);
	dmibar_write32(DMILCAP, reg32);

	reg32 = dmibar_read32(DMICC);
	reg32 &= 0x00ffffff;
	reg32 &= ~(3 << 0);
	reg32 |= (1 << 0);
	reg32 &= ~(3 << 20);
	reg32 |= (1 << 20);

	dmibar_write32(DMICC, reg32);

	if (activate_aspm)
		dmibar_setbits32(DMILCTL, 3 << 0);

	/* Last but not least, some additional steps */
	reg32 = mchbar_read32(FSBSNPCTL);
	reg32 &= ~(0xff << 2);
	reg32 |= (0xaa << 2);
	mchbar_write32(FSBSNPCTL, reg32);

	dmibar_write32(0x2c, 0x86000040);

	reg32 = dmibar_read32(0x204);
	reg32 &= ~0x3ff;
#if 1
	reg32 |= 0x13f;	/* for x4 DMI only */
#else
	reg32 |= 0x1e4;	/* for x2 DMI only */
#endif
	dmibar_write32(0x204, reg32);

	if (pci_read_config8(HOST_BRIDGE, DEVEN) & (DEVEN_D2F0 | DEVEN_D2F1)) {
		printk(BIOS_DEBUG, "Internal graphics: enabled\n");
		dmibar_setbits32(0x200, 1 << 21);
	} else {
		printk(BIOS_DEBUG, "Internal graphics: disabled\n");
		dmibar_clrbits32(0x200, 1 << 21);
	}

	reg32 = dmibar_read32(0x204);
	reg32 &= ~((1 << 11) | (1 << 10));
	dmibar_write32(0x204, reg32);

	reg32 = dmibar_read32(0x204);
	reg32 &= ~(0xff << 12);
	reg32 |= (0x0d << 12);
	dmibar_write32(0x204, reg32);

	dmibar_setbits32(DMICTL1, 3 << 24);

	reg32 = dmibar_read32(0x200);
	reg32 &= ~(0x3 << 26);
	reg32 |= (0x02 << 26);
	dmibar_write32(0x200, reg32);

	dmibar_clrbits32(DMIDRCCFG, 1 << 31);
	dmibar_setbits32(DMICTL2, 1 << 31);

	if (i945_silicon_revision() >= 3) {
		reg32 = dmibar_read32(0xec0);
		reg32 &= 0x0fffffff;
		reg32 |= (2 << 28);
		dmibar_write32(0xec0, reg32);

		reg32 = dmibar_read32(0xed4);
		reg32 &= 0x0fffffff;
		reg32 |= (2 << 28);
		dmibar_write32(0xed4, reg32);

		reg32 = dmibar_read32(0xee8);
		reg32 &= 0x0fffffff;
		reg32 |= (2 << 28);
		dmibar_write32(0xee8, reg32);

		reg32 = dmibar_read32(0xefc);
		reg32 &= 0x0fffffff;
		reg32 |= (2 << 28);
		dmibar_write32(0xefc, reg32);
	}

	/* wait for bit toggle to 0 */
	printk(BIOS_DEBUG, "Waiting for DMI hardware...");
	timeout = 0x7fffff;
	while ((dmibar_read8(0x32) & (1 << 1)) && --timeout)
		;
	if (!timeout)
		printk(BIOS_DEBUG, "timeout!\n");
	else
		printk(BIOS_DEBUG, "ok\n");

	/* Clear Error Status Bits! */
	dmibar_write32(0x1c4, 0xffffffff);
	dmibar_write32(0x1d0, 0xffffffff);
	dmibar_write32(0x228, 0xffffffff);

	/* Program Read-Only Write-Once Registers */
	dmibar_setbits32(0x308, 0);
	dmibar_setbits32(0x314, 0);
	dmibar_setbits32(0x324, 0);
	dmibar_setbits32(0x328, 0);
	dmibar_setbits32(0x334, 0);
	dmibar_setbits32(0x338, 0);

	if (i945_silicon_revision() == 1 && (mchbar_read8(DFT_STRAP1) & (1 << 5))) {
		if ((mchbar_read32(0x214) & 0xf) != 0x3) {
			printk(BIOS_INFO, "DMI link requires A1 stepping workaround. Rebooting.\n");
			reg32 = dmibar_read32(0x224);
			reg32 &= ~(7 << 0);
			reg32 |= (3 << 0);
			dmibar_write32(0x224, reg32);
			system_reset();
		}
	}
}

static void i945_setup_pci_express_x16(void)
{
	u32 timeout;
	u32 reg32;
	u16 reg16;
	const pci_devfn_t p2peg = PCI_DEV(0, 0x01, 0);

	u8 tmp_secondary = 0x0a;
	const pci_devfn_t peg_plugin = PCI_DEV(tmp_secondary, 0, 0);

	printk(BIOS_DEBUG, "Enabling PCI Express x16 Link\n");

	pci_or_config16(HOST_BRIDGE, DEVEN, DEVEN_D1F0);

	pci_and_config32(p2peg, PEGCC, ~(1 << 8));

	/* We have no success with querying the usual PCIe registers
	 * for link setup success on the i945. Hence we assign a temporary
	 * PCI bus 0x0a and check whether we find a device on 0:a.0
	 */

	/* Force PCIRST# */
	pci_s_assert_secondary_reset(p2peg);
	pci_s_deassert_secondary_reset(p2peg);

	reg16 = pci_read_config16(p2peg, SLOTSTS);
	printk(BIOS_DEBUG, "SLOTSTS: %04x\n", reg16);
	if (!(reg16 & 0x48))
		goto disable_pciexpress_x16_link;
	reg16 |= (1 << 4) | (1 << 0);
	pci_write_config16(p2peg, SLOTSTS, reg16);

	pci_s_bridge_set_secondary(p2peg, tmp_secondary);

	pci_and_config32(p2peg, 0x224, ~(1 << 8));

	mchbar_clrbits16(UPMC1, 1 << 5 | 1 << 0);

	/* Initialize PEG_CAP */
	pci_or_config16(p2peg, PEG_CAP, 1 << 8);

	/* Setup SLOTCAP */
	/* TODO: These values are mainboard dependent and should be set from devicetree.cb.
	 */
	/* NOTE: SLOTCAP becomes RO after the first write! */
	reg32 = pci_read_config32(p2peg, SLOTCAP);
	reg32 &= 0x0007ffff;

	reg32 &= 0xfffe007f;

	pci_write_config32(p2peg, SLOTCAP, reg32);

	/* Wait for training to succeed */
	printk(BIOS_DEBUG, "PCIe link training ...");
	timeout = 0x7ffff;
	while ((((pci_read_config32(p2peg, PEGSTS) >> 16) & 3) != 3) && --timeout)
		;

	reg32 = pci_read_config32(peg_plugin, PCI_VENDOR_ID);
	if (reg32 != 0x00000000 && reg32 != 0xffffffff) {
		printk(BIOS_DEBUG, " Detected PCIe device %04x:%04x\n",
				reg32 & 0xffff, reg32 >> 16);
	} else {
		printk(BIOS_DEBUG, " timeout!\n");

		printk(BIOS_DEBUG, "Restrain PCIe port to x1\n");

		pci_update_config32(p2peg, PEGSTS, ~(0xf << 1), 1);

		/* Force PCIRST# */
		pci_s_assert_secondary_reset(p2peg);
		pci_s_deassert_secondary_reset(p2peg);

		printk(BIOS_DEBUG, "PCIe link training ...");
		timeout = 0x7ffff;
		while ((((pci_read_config32(p2peg, PEGSTS) >> 16) & 3) != 3) && --timeout)
			;

		reg32 = pci_read_config32(peg_plugin, PCI_VENDOR_ID);
		if (reg32 != 0x00000000 && reg32 != 0xffffffff) {
			printk(BIOS_DEBUG, " Detected PCIe x1 device %04x:%04x\n",
				reg32 & 0xffff, reg32 >> 16);
		} else {
			printk(BIOS_DEBUG, " timeout!\n");
			printk(BIOS_DEBUG, "Disabling PCIe x16 port completely.\n");
			goto disable_pciexpress_x16_link;
		}
	}

	reg16 = pci_read_config16(p2peg, 0xb2);
	reg16 >>= 4;
	reg16 &= 0x3f;
	/* reg16 == 1 -> x1; reg16 == 16 -> x16 */
	printk(BIOS_DEBUG, "PCIe x%d link training succeeded.\n", reg16);

	reg32 = pci_read_config32(p2peg, PEGTC);
	reg32 &= 0xfffffc00; /* clear [9:0] */
	if (reg16 == 1)
		reg32 |= 0x32b;
		// TODO
		/* pci_write_config32(p2peg, PEGTC, reg32); */
	else if (reg16 == 16)
		reg32 |= 0x0f4;
		// TODO
		/* pci_write_config32(p2peg, PEGTC, reg32); */

	reg32 = (pci_read_config32(peg_plugin, 0x8) >> 8);
	printk(BIOS_DEBUG, "PCIe device class: %06x\n", reg32);
	if (reg32 == 0x030000) {
		printk(BIOS_DEBUG, "PCIe device is VGA. Disabling IGD.\n");
		reg16 = (1 << 1);
		pci_write_config16(HOST_BRIDGE, GGC, reg16);

		pci_and_config32(HOST_BRIDGE, DEVEN, ~(DEVEN_D2F0 | DEVEN_D2F1));
	}

	/* Enable GPEs: PMEGPE, HPGPE, GENGPE */
	pci_or_config32(p2peg, PEG_LC, (1 << 2) | (1 << 1) | (1 << 0));

	/* Virtual Channel Configuration: Only VC0 on PCIe x16 */
	pci_and_config32(p2peg, VC0RCTL, ~0x000000fe);

	/* Extended VC count */
	pci_and_config32(p2peg, PVCCAP1, ~(7 << 0));

	/* Active State Power Management ASPM */

	/* TODO */

	/* Clear error bits */
	pci_write_config16(p2peg, PCISTS1, 0xffff);
	pci_write_config16(p2peg, SSTS1, 0xffff);
	pci_write_config16(p2peg, DSTS, 0xffff);
	pci_write_config32(p2peg, UESTS, 0xffffffff);
	pci_write_config32(p2peg, CESTS, 0xffffffff);
	pci_write_config32(p2peg, 0x1f0, 0xffffffff);
	pci_write_config32(p2peg, 0x228, 0xffffffff);

	/* Program R/WO registers */
	pci_update_config32(p2peg, 0x308, ~0, 0);
	pci_update_config32(p2peg, 0x314, ~0, 0);
	pci_update_config32(p2peg, 0x324, ~0, 0);
	pci_update_config32(p2peg, 0x328, ~0, 0);

	/* Additional PCIe graphics setup */
	pci_or_config32(p2peg, 0xf0, 3 << 26);
	pci_or_config32(p2peg, 0xf0, 3 << 24);
	pci_or_config32(p2peg, 0xf0, 1 <<  5);

	pci_update_config32(p2peg, 0x200, ~(3 << 26), 2 << 26);

	reg32 = pci_read_config32(p2peg, 0xe80);
	if (i945_silicon_revision() >= 2)
		reg32 |= (1 << 12);
	else
		reg32 &= ~(1 << 12);
	pci_write_config32(p2peg, 0xe80, reg32);

	pci_and_config32(p2peg, 0xeb4, ~(1 << 31));

	pci_or_config32(p2peg, 0xfc, 1 << 31);

	if (i945_silicon_revision() >= 3) {
		static const u32 reglist[] = {
			0xec0, 0xed4, 0xee8, 0xefc, 0xf10, 0xf24, 0xf38, 0xf4c,
			0xf60, 0xf74, 0xf88, 0xf9c, 0xfb0, 0xfc4, 0xfd8, 0xfec
		};

		int i;
		for (i = 0; i < ARRAY_SIZE(reglist); i++)
			pci_update_config32(p2peg, reglist[i], ~(0xf << 28), 2 << 28);
	}

	if (i945_silicon_revision() <= 2) {
		/* Set voltage specific parameters */
		reg32 = pci_read_config32(p2peg, 0xe80);
		reg32 &= (0xf << 4);	/* Default case 1.05V */
		if ((mchbar_read32(DFT_STRAP1) & (1 << 20)) == 0) {	/* 1.50V */
			reg32 |= (7 << 4);
		}
		pci_write_config32(p2peg, 0xe80, reg32);
	}

	return;

disable_pciexpress_x16_link:
	/* For now we just disable the x16 link */
	printk(BIOS_DEBUG, "Disabling PCI Express x16 Link\n");

	mchbar_setbits16(UPMC1, 1 << 5 | 1 << 0);

	/* Toggle PCIRST# */
	pci_s_assert_secondary_reset(p2peg);

	pci_or_config32(p2peg, 0x224, 1 << 8);

	pci_s_deassert_secondary_reset(p2peg);

	printk(BIOS_DEBUG, "Wait for link to enter detect state... ");
	timeout = 0x7fffff;
	for (reg32 = pci_read_config32(p2peg, PEGSTS);
	     (reg32 & 0x000f0000) && --timeout;)
		;
	if (!timeout)
		printk(BIOS_DEBUG, "timeout!\n");
	else
		printk(BIOS_DEBUG, "ok\n");

	/* Finally: Disable the PCI config header */
	pci_and_config16(HOST_BRIDGE, DEVEN, ~DEVEN_D1F0);
}

static void i945_setup_root_complex_topology(void)
{
	u32 reg32;
	const pci_devfn_t p2peg = PCI_DEV(0, 0x01, 0);

	printk(BIOS_DEBUG, "Setting up Root Complex Topology\n");
	/* Egress Port Root Topology */

	reg32 = epbar_read32(EPESD);
	reg32 &= 0xff00ffff;
	reg32 |= (1 << 16);
	epbar_write32(EPESD, reg32);

	epbar_setbits32(EPLE1D, 1 << 16 | 1 << 0);

	epbar_write32(EPLE1A, CONFIG_FIXED_DMIBAR_MMIO_BASE);

	epbar_setbits32(EPLE2D, 1 << 16 | 1 << 0);

	/* DMI Port Root Topology */

	reg32 = dmibar_read32(DMILE1D);
	reg32 &= 0x00ffffff;

	reg32 &= 0xff00ffff;
	reg32 |= (2 << 16);

	reg32 |= (1 << 0);
	dmibar_write32(DMILE1D, reg32);

	dmibar_write32(DMILE1A, CONFIG_FIXED_RCBA_MMIO_BASE);

	dmibar_setbits32(DMILE2D, 1 << 16 | 1 << 0);

	dmibar_write32(DMILE2A, CONFIG_FIXED_EPBAR_MMIO_BASE);

	/* PCI Express x16 Port Root Topology */
	if (pci_read_config8(HOST_BRIDGE, DEVEN) & DEVEN_D1F0) {
		pci_write_config32(p2peg, LE1A, CONFIG_FIXED_EPBAR_MMIO_BASE);
		pci_or_config32(p2peg, LE1D, 1 << 0);
	}
}

static void ich7_setup_root_complex_topology(void)
{
	/* Write the R/WO registers */

	RCBA32(ESD) |= (2 << 16);

	RCBA32(ULD) |= (1 << 24) | (1 << 16);

	RCBA32(ULBA) = CONFIG_FIXED_DMIBAR_MMIO_BASE;
	/* Write ESD.CID to TCID */
	RCBA32(RP1D) |= (2 << 16);
	RCBA32(RP2D) |= (2 << 16);
	RCBA32(RP3D) |= (2 << 16);
	RCBA32(RP4D) |= (2 << 16);
	RCBA32(HDD)  |= (2 << 16);
	RCBA32(RP5D) |= (2 << 16);
	RCBA32(RP6D) |= (2 << 16);
}

static void ich7_setup_pci_express(void)
{
	/* Enable PCIe Root Port Clock Gate */
	RCBA32(CG) |= (1 << 0);

	/* Initialize slot power limit for root ports */
	pci_write_config32(PCI_DEV(0, 0x1c, 0), 0x54, 0x00000060);

	pci_write_config32(PCI_DEV(0, 0x1c, 0), 0xd8, 0x00110000);
}

void i945_early_initialization(void)
{
	/* Print some chipset specific information */
	switch (pci_read_config32(HOST_BRIDGE, 0)) {
	case 0x27708086: /* 82945G/GZ/GC/P/PL */
		i945_detect_chipset();
		break;
	case 0x27a08086: /* 945GME/GSE */
	case 0x27ac8086: /* 945GM/PM/GMS/GU/GT, 943/940GML */
		i945m_detect_chipset();
		break;
	}

	/* Setup all BARs required for early PCIe and raminit */
	i945_setup_bars();

	/* Change port80 to LPC */
	RCBA32(GCS) &= (~0x04);

	/* Just do it that way */
	RCBA32(0x2010) |= (1 << 10);
}

static void i945_prepare_resume(int s3resume)
{
	int cbmem_was_initted;

	cbmem_was_initted = !cbmem_recovery(s3resume);

	romstage_handoff_init(cbmem_was_initted && s3resume);
}

void i945_late_initialization(int s3resume)
{
	i945_setup_egress_port();

	ich7_setup_root_complex_topology();

	ich7_setup_pci_express();

	ich7_setup_dmi_rcrb();

	i945_setup_dmi_rcrb();

	if (CONFIG(NORTHBRIDGE_INTEL_SUBTYPE_I945GM))
		i945_setup_pci_express_x16();

	i945_setup_root_complex_topology();

	if (CONFIG(DEBUG_RAM_SETUP))
		sdram_dump_mchbar_registers();

	mchbar_write16(SSKPD, 0xcafe);

	i945_prepare_resume(s3resume);
}