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authorAndrey Petrov <andrey.petrov@intel.com>2017-06-05 13:22:41 -0700
committerAaron Durbin <adurbin@chromium.org>2017-07-13 19:28:34 +0000
commitf35804ba6f14d748568119206bdfe26046c9606b (patch)
tree5bed2331de7131a3df0d3a96407e4ec5709ba6f8 /src/soc
parent3e2e0508c2f41242355dfbfe42b9e34adcb1a92a (diff)
downloadcoreboot-f35804ba6f14d748568119206bdfe26046c9606b.tar.xz
soc/intel/cannonlake: Add bootblock PCH
Add essential initialization needed for PCH in bootblock. Change-Id: I3694e099e78c2989f7192c550cbba098e5df2032 Signed-off-by: Andrey Petrov <andrey.petrov@intel.com> Reviewed-on: https://review.coreboot.org/20067 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'src/soc')
-rw-r--r--src/soc/intel/cannonlake/bootblock/pch.c199
-rw-r--r--src/soc/intel/cannonlake/include/soc/lpc.h55
-rw-r--r--src/soc/intel/cannonlake/include/soc/p2sb.h27
-rw-r--r--src/soc/intel/cannonlake/include/soc/pch.h32
-rw-r--r--src/soc/intel/cannonlake/include/soc/pcr_ids.h38
-rw-r--r--src/soc/intel/cannonlake/include/soc/smbus.h47
-rw-r--r--src/soc/intel/cannonlake/include/soc/systemagent.h104
7 files changed, 502 insertions, 0 deletions
diff --git a/src/soc/intel/cannonlake/bootblock/pch.c b/src/soc/intel/cannonlake/bootblock/pch.c
new file mode 100644
index 0000000000..9d326bb7c5
--- /dev/null
+++ b/src/soc/intel/cannonlake/bootblock/pch.c
@@ -0,0 +1,199 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 Google Inc.
+ * Copyright (C) 2017 Intel Corporation.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#include <device/device.h>
+#include <intelblocks/cse.h>
+#include <intelblocks/fast_spi.h>
+#include <intelblocks/pcr.h>
+#include <intelblocks/rtc.h>
+#include <intelblocks/smbus.h>
+#include <soc/bootblock.h>
+#include <soc/iomap.h>
+#include <soc/lpc.h>
+#include <soc/p2sb.h>
+#include <soc/pci_devs.h>
+#include <soc/pcr_ids.h>
+#include <soc/pmc.h>
+#include <soc/smbus.h>
+
+#define PCR_PSF3_TO_SHDW_PMC_REG_BASE 0x1400
+#define PCR_PSFX_TO_SHDW_BAR0 0
+#define PCR_PSFX_TO_SHDW_BAR1 0x4
+#define PCR_PSFX_TO_SHDW_BAR2 0x8
+#define PCR_PSFX_TO_SHDW_BAR3 0xC
+#define PCR_PSFX_TO_SHDW_BAR4 0x10
+#define PCR_PSFX_TO_SHDW_PCIEN_IOEN 0x01
+#define PCR_PSFX_T0_SHDW_PCIEN 0x1C
+
+#define PCR_DMI_LPCLGIR1 0x2730
+#define PCR_DMI_LPCLGIR2 0x2734
+#define PCR_DMI_LPCLGIR3 0x2738
+#define PCR_DMI_LPCLGIR4 0x273c
+
+#define PCR_DMI_ACPIBA 0x27B4
+#define PCR_DMI_ACPIBDID 0x27B8
+#define PCR_DMI_PMBASEA 0x27AC
+#define PCR_DMI_PMBASEC 0x27B0
+#define PCR_DMI_TCOBASE 0x2778
+#define TCOEN (1 << 1) /* Enable TCO I/O range decode. */
+
+#define PCR_DMI_LPCIOD 0x2770
+#define PCR_DMI_LPCIOE 0x2774
+
+static void enable_p2sbbar(void)
+{
+ device_t dev = PCH_DEV_P2SB;
+
+ /* Enable PCR Base address in PCH */
+ pci_write_config32(dev, PCI_BASE_ADDRESS_0, CONFIG_PCR_BASE_ADDRESS);
+
+ /* Enable P2SB MSE */
+ pci_write_config8(dev, PCI_COMMAND,
+ PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
+ /*
+ * Enable decoding for HPET memory address range.
+ * HPTC_OFFSET(0x60) bit 7, when set the P2SB will decode
+ * the High Performance Timer memory address range
+ * selected by bits 1:0
+ */
+ pci_write_config8(dev, HPTC_OFFSET, HPTC_ADDR_ENABLE_BIT);
+}
+
+static void soc_config_pwrmbase(void)
+{
+ uint32_t reg32;
+
+ /* Assign Resources to PWRMBASE */
+ /* Clear BIT 1-2 Command Register */
+ reg32 = pci_read_config32(PCH_DEV_PMC, PCI_COMMAND);
+ reg32 &= ~(PCI_COMMAND_MEMORY);
+ pci_write_config32(PCH_DEV_PMC, PCI_COMMAND, reg32);
+
+ /* Program PWRM Base */
+ pci_write_config32(PCH_DEV_PMC, PWRMBASE, PCH_PWRM_BASE_ADDRESS);
+
+ /* Enable Bus Master and MMIO Space */
+ reg32 = pci_read_config32(PCH_DEV_PMC, PCI_COMMAND);
+ reg32 |= PCI_COMMAND_MEMORY;
+ pci_write_config32(PCH_DEV_PMC, PCI_COMMAND, reg32);
+
+ /* Enable PWRM in PMC */
+ reg32 = read32((void *)(PCH_PWRM_BASE_ADDRESS + ACTL));
+ write32((void *)(PCH_PWRM_BASE_ADDRESS + ACTL), reg32 | PWRM_EN);
+}
+
+void bootblock_pch_early_init(void)
+{
+ fast_spi_early_init(SPI_BASE_ADDRESS);
+ enable_p2sbbar();
+ /*
+ * Enabling PWRM Base for accessing
+ * Global Reset Cause Register.
+ */
+ soc_config_pwrmbase();
+}
+
+
+static void soc_config_acpibase(void)
+{
+ uint32_t pmc_reg_value;
+
+ pmc_reg_value = pcr_read32(PID_PSF3, PCR_PSF3_TO_SHDW_PMC_REG_BASE +
+ PCR_PSFX_TO_SHDW_BAR4);
+
+ if (pmc_reg_value != 0xFFFFFFFF)
+ {
+ /* Disable Io Space before changing the address */
+ pcr_rmw32(PID_PSF3, PCR_PSF3_TO_SHDW_PMC_REG_BASE +
+ PCR_PSFX_T0_SHDW_PCIEN,
+ ~PCR_PSFX_TO_SHDW_PCIEN_IOEN, 0);
+ /* Program ABASE in PSF3 PMC space BAR4*/
+ pcr_write32(PID_PSF3, PCR_PSF3_TO_SHDW_PMC_REG_BASE +
+ PCR_PSFX_TO_SHDW_BAR4,
+ ACPI_BASE_ADDRESS);
+ /* Enable IO Space */
+ pcr_rmw32(PID_PSF3, PCR_PSF3_TO_SHDW_PMC_REG_BASE +
+ PCR_PSFX_T0_SHDW_PCIEN,
+ ~0, PCR_PSFX_TO_SHDW_PCIEN_IOEN);
+ }
+}
+
+static void soc_config_tco(void)
+{
+ uint32_t reg32;
+ uint16_t tcobase;
+ uint16_t tcocnt;
+
+ /* Disable TCO in SMBUS Device first before changing Base Address */
+ reg32 = pci_read_config32(PCH_DEV_SMBUS, TCOCTL);
+ reg32 &= ~TCO_EN;
+ pci_write_config32(PCH_DEV_SMBUS, TCOCTL, reg32);
+
+ /* Program TCO Base */
+ tcobase = TCO_BASE_ADDRESS;
+ pci_write_config32(PCH_DEV_SMBUS, TCOBASE, tcobase);
+
+ /* Enable TCO in SMBUS */
+ pci_write_config32(PCH_DEV_SMBUS, TCOCTL, reg32 | TCO_BASE_EN);
+
+ /*
+ * Program "TCO Base Address" PCR[DMI] + 2778h[15:5, 1]
+ */
+ pcr_write32(PID_DMI, PCR_DMI_TCOBASE, tcobase | TCOEN);
+
+ /* Program TCO timer halt */
+ tcocnt = inw(tcobase + TCO1_CNT);
+ tcocnt |= TCO_TMR_HLT;
+ outw(tcocnt, tcobase + TCO1_CNT);
+}
+
+void pch_early_iorange_init(void)
+{
+ uint16_t dec_rng, dec_en = 0;
+
+ /* IO Decode Range */
+ if (IS_ENABLED(CONFIG_DRIVERS_UART_8250IO) &&
+ IS_ENABLED(CONFIG_UART_DEBUG)) {
+ dec_rng = COMA_RANGE | (COMB_RANGE << 4);
+ dec_en = COMA_LPC_EN | COMB_LPC_EN;
+ pci_write_config16(PCH_DEV_LPC, LPC_IO_DEC, dec_rng);
+ pcr_write16(PID_DMI, PCR_DMI_LPCIOD, dec_rng);
+ }
+
+ /* IO Decode Enable */
+ dec_en |= SE_LPC_EN | KBC_LPC_EN | MC1_LPC_EN;
+ pci_write_config16(PCH_DEV_LPC, LPC_EN, dec_en);
+ pcr_write16(PID_DMI, PCR_DMI_LPCIOE, dec_en);
+}
+
+void pch_early_init(void)
+{
+ /*
+ * Enabling ABASE for accessing PM1_STS, PM1_EN, PM1_CNT,
+ * GPE0_STS, GPE0_EN registers.
+ */
+ soc_config_acpibase();
+
+ /* Programming TCO_BASE_ADDRESS and TCO Timer Halt */
+ soc_config_tco();
+
+ /* Program SMBUS_BASE_ADDRESS and Enable it */
+ smbus_common_init();
+
+ enable_rtc_upper_bank();
+
+ heci_init(HECI1_BASE_ADDRESS);
+}
diff --git a/src/soc/intel/cannonlake/include/soc/lpc.h b/src/soc/intel/cannonlake/include/soc/lpc.h
new file mode 100644
index 0000000000..3488ee2b85
--- /dev/null
+++ b/src/soc/intel/cannonlake/include/soc/lpc.h
@@ -0,0 +1,55 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 Google Inc.
+ * Copyright (C) 2017 Intel Corporation.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef _SOC_CANNONLAKE_LPC_H_
+#define _SOC_CANNONLAKE_LPC_H_
+
+/* PCI Configuration Space (D31:F0): LPC */
+#define SCI_IRQ_SEL (7 << 0)
+#define SCIS_IRQ9 0
+#define SCIS_IRQ10 1
+#define SCIS_IRQ11 2
+#define SCIS_IRQ20 4
+#define SCIS_IRQ21 5
+#define SCIS_IRQ22 6
+#define SCIS_IRQ23 7
+#define SERIRQ_CNTL 0x64
+#define LPC_IO_DEC 0x80 /* IO Decode Ranges Register */
+#define COMA_RANGE 0x0 /* 0x3F8 - 0x3FF COM1*/
+#define COMB_RANGE 0x1 /* 0x2F8 - 0x2FF COM2*/
+#define LPC_EN 0x82 /* LPC IF Enables Register */
+#define MC2_LPC_EN (1 << 13) /* 0x4e/0x4f */
+#define SE_LPC_EN (1 << 12) /* 0x2e/0x2f */
+#define MC1_LPC_EN (1 << 11) /* 0x62/0x66 */
+#define KBC_LPC_EN (1 << 10) /* 0x60/0x64 */
+#define GAMEH_LPC_EN (1 << 9) /* 0x208/0x20f */
+#define GAMEL_LPC_EN (1 << 8) /* 0x200/0x207 */
+#define FDD_LPC_EN (1 << 3) /* Floppy Drive Enable */
+#define LPT_LPC_EN (1 << 2) /* Parallel Port Enable */
+#define COMB_LPC_EN (1 << 1) /* Com Port B Enable */
+#define COMA_LPC_EN (1 << 0) /* Com Port A Enable */
+#define LPC_GEN1_DEC 0x84 /* LPC IF Generic Decode Range 1 */
+#define LPC_GEN2_DEC 0x88 /* LPC IF Generic Decode Range 2 */
+#define LPC_GEN3_DEC 0x8c /* LPC IF Generic Decode Range 3 */
+#define LPC_GEN4_DEC 0x90 /* LPC IF Generic Decode Range 4 */
+#define LGMR 0x98 /* LPC Generic Memory Range */
+#define BIOS_CNTL 0xdc
+#define LPC_BC_BILD (1 << 7) /* BILD */
+#define LPC_BC_LE (1 << 2) /* LE */
+#define LPC_BC_EISS (1 << 5) /* EISS */
+#define PCCTL 0xE0 /* PCI Clock Control */
+#define CLKRUN_EN (1 << 0)
+#endif
diff --git a/src/soc/intel/cannonlake/include/soc/p2sb.h b/src/soc/intel/cannonlake/include/soc/p2sb.h
new file mode 100644
index 0000000000..1f209ed862
--- /dev/null
+++ b/src/soc/intel/cannonlake/include/soc/p2sb.h
@@ -0,0 +1,27 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2017 Intel Corporation.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef _SOC_CANNONLAKE_P2SB_H_
+#define _SOC_CANNONLAKE_P2SB_H_
+
+#define HPTC_OFFSET 0x60
+#define HPTC_ADDR_ENABLE_BIT (1 << 7)
+
+#define PCH_P2SB_EPMASK0 0x220
+#define PCH_P2SB_EPMASK(mask_number) (PCH_P2SB_EPMASK0 + (mask_number * 4))
+
+#define PCH_P2SB_E0 0xE0
+
+#endif
diff --git a/src/soc/intel/cannonlake/include/soc/pch.h b/src/soc/intel/cannonlake/include/soc/pch.h
new file mode 100644
index 0000000000..d8b3b955b6
--- /dev/null
+++ b/src/soc/intel/cannonlake/include/soc/pch.h
@@ -0,0 +1,32 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2008-2009 coresystems GmbH
+ * Copyright (C) 2014 Google Inc.
+ * Copyright (C) 2017 Intel Corporation.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef _SOC_CANNONLAKE_PCH_H_
+#define _SOC_CANNONLAKE_PCH_H_
+
+#include <stdint.h>
+
+#define PCH_H 1
+#define PCH_LP 2
+#define PCH_UNKNOWN_SERIES 0xFF
+
+u8 pch_revision(void);
+u16 pch_type(void);
+void pch_log_state(void);
+void pch_uart_init(void);
+
+#endif
diff --git a/src/soc/intel/cannonlake/include/soc/pcr_ids.h b/src/soc/intel/cannonlake/include/soc/pcr_ids.h
new file mode 100644
index 0000000000..65576aabcb
--- /dev/null
+++ b/src/soc/intel/cannonlake/include/soc/pcr_ids.h
@@ -0,0 +1,38 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (c) 2017 Intel Corp.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef SOC_CANNONLAKE_PCR_H
+#define SOC_CANNONLAKE_PCR_H
+/*
+ * Port ids
+ */
+#define PID_GPIOCOM4 0x6a
+#define PID_GPIOCOM3 0x6b
+#define PID_GPIOCOM2 0x6c
+#define PID_GPIOCOM1 0x6d
+#define PID_GPIOCOM0 0x6e
+#define PID_DMI 0x88
+#define PID_PSTH 0x89
+#define PID_PSF1 0xba
+#define PID_PSF2 0xbb
+#define PID_PSF3 0xbc
+#define PID_PSF4 0xbd
+#define PID_SCS 0xc0
+#define PID_RTC 0xc3
+#define PID_ITSS 0xc2
+#define PID_LPC 0xc7
+#define PID_SERIALIO 0xcb
+
+#endif
diff --git a/src/soc/intel/cannonlake/include/soc/smbus.h b/src/soc/intel/cannonlake/include/soc/smbus.h
new file mode 100644
index 0000000000..9de6981d5a
--- /dev/null
+++ b/src/soc/intel/cannonlake/include/soc/smbus.h
@@ -0,0 +1,47 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2005 Yinghai Lu <yinghailu@gmail.com>
+ * Copyright (C) 2009 coresystems GmbH
+ * Copyright (C) 2014 Google Inc.
+ * Copyright (C) 2017 Intel Corporation.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef _SOC_CANNONLAKE_SMBUS_H_
+#define _SOC_CANNONLAKE_SMBUS_H_
+
+/* PCI registers */
+#define TCOBASE 0x50 /* TCO base address. */
+#define TCOCTL 0x54
+#define TCO_BASE_EN (1 << 8) /* TCO base enable. */
+
+/* IO and MMIO registers under primary BAR */
+/* Set address for PCH as SMBus slave role */
+#define SMB_RCV_SLVA 0x09
+
+/* TCO registers and fields live behind TCOBASE I/O bar in SMBus device. */
+#define TCO1_STS 0x04
+#define TCO2_STS 0x06
+#define TCO2_STS_SECOND_TO 0x02
+#define TCO2_STS_BOOT 0x04
+#define TCO1_CNT 0x08
+#define TCO_LOCK (1 << 12)
+#define TCO_TMR_HLT (1 << 11)
+
+/*
+ * Default slave address value for PCH. This value is set to match default
+ * value set by hardware. It is useful since PCH is able to respond even
+ * before CPU is up. This is reset by RSMRST# but not by PLTRST#.
+ */
+#define SMBUS_SLAVE_ADDR 0x44
+
+#endif
diff --git a/src/soc/intel/cannonlake/include/soc/systemagent.h b/src/soc/intel/cannonlake/include/soc/systemagent.h
new file mode 100644
index 0000000000..b06945084e
--- /dev/null
+++ b/src/soc/intel/cannonlake/include/soc/systemagent.h
@@ -0,0 +1,104 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2007-2008 coresystems GmbH
+ * Copyright (C) 2014 Google Inc.
+ * Copyright (C) 2017 Intel Corporation.
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef SOC_CANNONLAKE_SYSTEMAGENT_H
+#define SOC_CANNONLAKE_SYSTEMAGENT_H
+
+#include <intelblocks/systemagent.h>
+#include <soc/iomap.h>
+
+/* Device 0:0.0 PCI configuration space */
+
+#define EPBAR 0x40
+#define PCIEXBAR 0x60
+#define DMIBAR 0x68
+#define GGC 0x50 /* GMCH Graphics Control */
+#define DEVEN 0x54 /* Device Enable */
+#define DEVEN_D7EN (1 << 14)
+#define DEVEN_D4EN (1 << 7)
+#define DEVEN_D3EN (1 << 5)
+#define DEVEN_D2EN (1 << 4)
+#define DEVEN_D1F0EN (1 << 3)
+#define DEVEN_D1F1EN (1 << 2)
+#define DEVEN_D1F2EN (1 << 1)
+#define DEVEN_D0EN (1 << 0)
+#define DPR 0x5c
+#define DPR_EPM (1 << 2)
+#define DPR_PRS (1 << 1)
+#define DPR_SIZE_MASK 0xff0
+
+#define PAM0 0x80
+#define PAM1 0x81
+#define PAM2 0x82
+#define PAM3 0x83
+#define PAM4 0x84
+#define PAM5 0x85
+#define PAM6 0x86
+
+#define SMRAM 0x88 /* System Management RAM Control */
+#define D_OPEN (1 << 6)
+#define D_CLS (1 << 5)
+#define D_LCK (1 << 4)
+#define G_SMRAME (1 << 3)
+#define C_BASE_SEG ((0 << 2) | (1 << 1) | (0 << 0))
+
+#define MESEG_BASE 0x70 /* Management Engine Base. */
+#define MESEG_LIMIT 0x78 /* Management Engine Limit. */
+#define TOM 0xa0 /* Top of DRAM in memory controller space. */
+#define SKPAD 0xdc /* Scratchpad Data */
+
+/* MCHBAR */
+
+#define MCHBAR8(x) (*(volatile u8 *)(MCH_BASE_ADDRESS + x))
+#define MCHBAR16(x) (*(volatile u16 *)(MCH_BASE_ADDRESS + x))
+#define MCHBAR32(x) (*(volatile u32 *)(MCH_BASE_ADDRESS + x))
+
+#define MCHBAR_PEI_VERSION 0x5034
+#define REMAPBASE 0x5090 /* Remap base. */
+#define REMAPLIMIT 0x5098 /* Remap limit. */
+#define BIOS_RESET_CPL 0x5da8
+#define EDRAMBAR 0x5408
+#define MCH_PAIR 0x5418
+#define REGBAR 0x5420
+
+#define MCH_PKG_POWER_LIMIT_LO 0x59a0
+#define MCH_PKG_POWER_LIMIT_HI 0x59a4
+#define MCH_DDR_POWER_LIMIT_LO 0x58e0
+#define MCH_DDR_POWER_LIMIT_HI 0x58e4
+
+/* PCODE MMIO communications live in the MCHBAR. */
+#define BIOS_MAILBOX_INTERFACE 0x5da4
+#define MAILBOX_RUN_BUSY (1 << 31)
+/* Errors are returned back in bits 7:0. */
+#define MAILBOX_BIOS_ERROR_NONE 0
+#define MAILBOX_BIOS_ERROR_INVALID_COMMAND 1
+#define MAILBOX_BIOS_ERROR_TIMEOUT 2
+#define MAILBOX_BIOS_ERROR_ILLEGAL_DATA 3
+#define MAILBOX_BIOS_ERROR_RESERVED 4
+#define MAILBOX_BIOS_ERROR_ILLEGAL_VR_ID 5
+#define MAILBOX_BIOS_ERROR_VR_INTERFACE_LOCKED 6
+#define MAILBOX_BIOS_ERROR_VR_ERROR 7
+/* Data is passed through bits 31:0 of the data register. */
+#define BIOS_MAILBOX_DATA 0x5da0
+
+/* System Agent identification */
+u8 systemagent_revision(void);
+
+/* Top of 32bit usable memory */
+u32 top_of_32bit_ram(void);
+
+#endif