2 * From Coreboot northbridge/intel/sandybridge/northbridge.c
4 * Copyright (C) 2007-2009 coresystems GmbH
5 * Copyright (C) 2011 The Chromium Authors
7 * SPDX-License-Identifier: GPL-2.0
16 #include <asm/processor.h>
17 #include <asm/arch/pch.h>
18 #include <asm/arch/model_206ax.h>
19 #include <asm/arch/sandybridge.h>
21 static int bridge_revision_id = -1;
23 int bridge_silicon_revision(void)
25 if (bridge_revision_id < 0) {
26 struct cpuid_result result;
27 uint8_t stepping, bridge_id;
31 stepping = result.eax & 0xf;
32 dev = PCI_BDF(0, 0, 0);
33 bridge_id = x86_pci_read_config16(dev, PCI_DEVICE_ID) & 0xf0;
34 bridge_revision_id = bridge_id | stepping;
37 return bridge_revision_id;
41 * Reserve everything between A segment and 1MB:
43 * 0xa0000 - 0xbffff: legacy VGA
44 * 0xc0000 - 0xcffff: VGA OPROM (needed by kernel)
45 * 0xe0000 - 0xfffff: SeaBIOS, if used, otherwise DMI
47 static const int legacy_hole_base_k = 0xa0000 / 1024;
48 static const int legacy_hole_size_k = 384;
50 static int get_pcie_bar(u32 *base, u32 *len)
52 pci_dev_t dev = PCI_BDF(0, 0, 0);
58 pciexbar_reg = x86_pci_read_config32(dev, PCIEXBAR);
60 if (!(pciexbar_reg & (1 << 0)))
63 switch ((pciexbar_reg >> 1) & 3) {
65 *base = pciexbar_reg & ((1 << 31) | (1 << 30) | (1 << 29) |
67 *len = 256 * 1024 * 1024;
70 *base = pciexbar_reg & ((1 << 31) | (1 << 30) | (1 << 29) |
71 (1 << 28) | (1 << 27));
72 *len = 128 * 1024 * 1024;
75 *base = pciexbar_reg & ((1 << 31) | (1 << 30) | (1 << 29) |
76 (1 << 28) | (1 << 27) | (1 << 26));
77 *len = 64 * 1024 * 1024;
84 static void add_fixed_resources(pci_dev_t dev, int index)
86 u32 pcie_config_base, pcie_config_size;
88 if (get_pcie_bar(&pcie_config_base, &pcie_config_size)) {
89 debug("Adding PCIe config bar base=0x%08x size=0x%x\n",
90 pcie_config_base, pcie_config_size);
94 static void northbridge_dmi_init(pci_dev_t dev)
96 /* Clear error status bits */
97 writel(0xffffffff, DMIBAR_REG(0x1c4));
98 writel(0xffffffff, DMIBAR_REG(0x1d0));
100 /* Steps prior to DMI ASPM */
101 if ((bridge_silicon_revision() & BASE_REV_MASK) == BASE_REV_SNB) {
102 clrsetbits_le32(DMIBAR_REG(0x250), (1 << 22) | (1 << 20),
106 setbits_le32(DMIBAR_REG(0x238), 1 << 29);
108 if (bridge_silicon_revision() >= SNB_STEP_D0) {
109 setbits_le32(DMIBAR_REG(0x1f8), 1 << 16);
110 } else if (bridge_silicon_revision() >= SNB_STEP_D1) {
111 clrsetbits_le32(DMIBAR_REG(0x1f8), 1 << 26, 1 << 16);
112 setbits_le32(DMIBAR_REG(0x1fc), (1 << 12) | (1 << 23));
115 /* Enable ASPM on SNB link, should happen before PCH link */
116 if ((bridge_silicon_revision() & BASE_REV_MASK) == BASE_REV_SNB)
117 setbits_le32(DMIBAR_REG(0xd04), 1 << 4);
119 setbits_le32(DMIBAR_REG(0x88), (1 << 1) | (1 << 0));
122 void northbridge_init(pci_dev_t dev)
126 add_fixed_resources(dev, 6);
127 northbridge_dmi_init(dev);
129 bridge_type = readl(MCHBAR_REG(0x5f10));
130 bridge_type &= ~0xff;
132 if ((bridge_silicon_revision() & BASE_REV_MASK) == BASE_REV_IVB) {
133 /* Enable Power Aware Interrupt Routing - fixed priority */
134 clrsetbits_8(MCHBAR_REG(0x5418), 0xf, 0x4);
136 /* 30h for IvyBridge */
139 /* 20h for Sandybridge */
142 writel(bridge_type, MCHBAR_REG(0x5f10));
145 * Set bit 0 of BIOS_RESET_CPL to indicate to the CPU
146 * that BIOS has initialized memory and power management
148 setbits_8(MCHBAR_REG(BIOS_RESET_CPL), 1);
149 debug("Set BIOS_RESET_CPL\n");
151 /* Configure turbo power limits 1ms after reset complete bit */
153 set_power_limits(28);
156 * CPUs with configurable TDP also need power limits set
157 * in MCHBAR. Use same values from MSR_PKG_POWER_LIMIT.
159 if (cpu_config_tdp_levels()) {
160 msr_t msr = msr_read(MSR_PKG_POWER_LIMIT);
162 writel(msr.lo, MCHBAR_REG(0x59A0));
163 writel(msr.hi, MCHBAR_REG(0x59A4));
166 /* Set here before graphics PM init */
167 writel(0x00100001, MCHBAR_REG(0x5500));
170 void northbridge_enable(pci_dev_t dev)
172 #if CONFIG_HAVE_ACPI_RESUME
173 switch (x86_pci_read_config32(dev, SKPAD)) {
175 debug("Normal boot.\n");
176 apci_set_slp_type(0);
179 debug("S3 Resume.\n");
180 apci_set_slp_type(3);
183 debug("Unknown boot method, assuming normal.\n");
184 apci_set_slp_type(0);