xref: /openbmc/u-boot/arch/x86/cpu/coreboot/coreboot.c (revision ee943655)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2011 The Chromium OS Authors.
4  * (C) Copyright 2008
5  * Graeme Russ, graeme.russ@gmail.com.
6  */
7 
8 #include <common.h>
9 #include <fdtdec.h>
10 #include <asm/io.h>
11 #include <asm/msr.h>
12 #include <asm/mtrr.h>
13 #include <asm/arch/sysinfo.h>
14 #include <asm/arch/timestamp.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 int arch_cpu_init(void)
19 {
20 	int ret = get_coreboot_info(&lib_sysinfo);
21 	if (ret != 0) {
22 		printf("Failed to parse coreboot tables.\n");
23 		return ret;
24 	}
25 
26 	timestamp_init();
27 
28 	return x86_cpu_init_f();
29 }
30 
31 int checkcpu(void)
32 {
33 	return 0;
34 }
35 
36 int print_cpuinfo(void)
37 {
38 	return default_print_cpuinfo();
39 }
40 
41 static void board_final_cleanup(void)
42 {
43 	/*
44 	 * Un-cache the ROM so the kernel has one
45 	 * more MTRR available.
46 	 *
47 	 * Coreboot should have assigned this to the
48 	 * top available variable MTRR.
49 	 */
50 	u8 top_mtrr = (native_read_msr(MTRR_CAP_MSR) & 0xff) - 1;
51 	u8 top_type = native_read_msr(MTRR_PHYS_BASE_MSR(top_mtrr)) & 0xff;
52 
53 	/* Make sure this MTRR is the correct Write-Protected type */
54 	if (top_type == MTRR_TYPE_WRPROT) {
55 		struct mtrr_state state;
56 
57 		mtrr_open(&state);
58 		wrmsrl(MTRR_PHYS_BASE_MSR(top_mtrr), 0);
59 		wrmsrl(MTRR_PHYS_MASK_MSR(top_mtrr), 0);
60 		mtrr_close(&state);
61 	}
62 
63 	if (!fdtdec_get_config_bool(gd->fdt_blob, "u-boot,no-apm-finalize")) {
64 		/*
65 		 * Issue SMI to coreboot to lock down ME and registers
66 		 * when allowed via device tree
67 		 */
68 		printf("Finalizing coreboot\n");
69 		outb(0xcb, 0xb2);
70 	}
71 }
72 
73 int last_stage_init(void)
74 {
75 	if (gd->flags & GD_FLG_COLD_BOOT)
76 		timestamp_add_to_bootstage();
77 
78 	board_final_cleanup();
79 
80 	return 0;
81 }
82 
83 int misc_init_r(void)
84 {
85 	return 0;
86 }
87