xref: /openbmc/u-boot/cmd/x86/mtrr.c (revision c83c436d)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2014 Google, Inc
4  */
5 
6 #include <common.h>
7 #include <asm/msr.h>
8 #include <asm/mtrr.h>
9 
10 static const char *const mtrr_type_name[MTRR_TYPE_COUNT] = {
11 	"Uncacheable",
12 	"Combine",
13 	"2",
14 	"3",
15 	"Through",
16 	"Protect",
17 	"Back",
18 };
19 
20 static int do_mtrr_list(void)
21 {
22 	int i;
23 
24 	printf("Reg Valid Write-type   %-16s %-16s %-16s\n", "Base   ||",
25 	       "Mask   ||", "Size   ||");
26 	for (i = 0; i < MTRR_COUNT; i++) {
27 		const char *type = "Invalid";
28 		uint64_t base, mask, size;
29 		bool valid;
30 
31 		base = native_read_msr(MTRR_PHYS_BASE_MSR(i));
32 		mask = native_read_msr(MTRR_PHYS_MASK_MSR(i));
33 		size = ~mask & ((1ULL << CONFIG_CPU_ADDR_BITS) - 1);
34 		size |= (1 << 12) - 1;
35 		size += 1;
36 		valid = mask & MTRR_PHYS_MASK_VALID;
37 		type = mtrr_type_name[base & MTRR_BASE_TYPE_MASK];
38 		printf("%d   %-5s %-12s %016llx %016llx %016llx\n", i,
39 		       valid ? "Y" : "N", type, base & ~MTRR_BASE_TYPE_MASK,
40 		       mask & ~MTRR_PHYS_MASK_VALID, size);
41 	}
42 
43 	return 0;
44 }
45 
46 static int do_mtrr_set(uint reg, int argc, char * const argv[])
47 {
48 	const char *typename = argv[0];
49 	struct mtrr_state state;
50 	uint32_t start, size;
51 	uint64_t base, mask;
52 	int i, type = -1;
53 	bool valid;
54 
55 	if (argc < 3)
56 		return CMD_RET_USAGE;
57 	for (i = 0; i < MTRR_TYPE_COUNT; i++) {
58 		if (*typename == *mtrr_type_name[i])
59 			type = i;
60 	}
61 	if (type == -1) {
62 		printf("Invalid type name %s\n", typename);
63 		return CMD_RET_USAGE;
64 	}
65 	start = simple_strtoul(argv[1], NULL, 16);
66 	size = simple_strtoul(argv[2], NULL, 16);
67 
68 	base = start | type;
69 	valid = native_read_msr(MTRR_PHYS_MASK_MSR(reg)) & MTRR_PHYS_MASK_VALID;
70 	mask = ~((uint64_t)size - 1);
71 	mask &= (1ULL << CONFIG_CPU_ADDR_BITS) - 1;
72 	if (valid)
73 		mask |= MTRR_PHYS_MASK_VALID;
74 
75 	printf("base=%llx, mask=%llx\n", base, mask);
76 	mtrr_open(&state, true);
77 	wrmsrl(MTRR_PHYS_BASE_MSR(reg), base);
78 	wrmsrl(MTRR_PHYS_MASK_MSR(reg), mask);
79 	mtrr_close(&state, true);
80 
81 	return 0;
82 }
83 
84 static int mtrr_set_valid(int reg, bool valid)
85 {
86 	struct mtrr_state state;
87 	uint64_t mask;
88 
89 	mtrr_open(&state, true);
90 	mask = native_read_msr(MTRR_PHYS_MASK_MSR(reg));
91 	if (valid)
92 		mask |= MTRR_PHYS_MASK_VALID;
93 	else
94 		mask &= ~MTRR_PHYS_MASK_VALID;
95 	wrmsrl(MTRR_PHYS_MASK_MSR(reg), mask);
96 	mtrr_close(&state, true);
97 
98 	return 0;
99 }
100 
101 static int do_mtrr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
102 {
103 	const char *cmd;
104 	uint reg;
105 
106 	cmd = argv[1];
107 	if (argc < 2 || *cmd == 'l')
108 		return do_mtrr_list();
109 	argc -= 2;
110 	argv += 2;
111 	if (argc <= 0)
112 		return CMD_RET_USAGE;
113 	reg = simple_strtoul(argv[0], NULL, 16);
114 	if (reg >= MTRR_COUNT) {
115 		printf("Invalid register number\n");
116 		return CMD_RET_USAGE;
117 	}
118 	if (*cmd == 'e')
119 		return mtrr_set_valid(reg, true);
120 	else if (*cmd == 'd')
121 		return mtrr_set_valid(reg, false);
122 	else if (*cmd == 's')
123 		return do_mtrr_set(reg, argc - 1, argv + 1);
124 	else
125 		return CMD_RET_USAGE;
126 
127 	return 0;
128 }
129 
130 U_BOOT_CMD(
131 	mtrr,	6,	1,	do_mtrr,
132 	"Use x86 memory type range registers (32-bit only)",
133 	"[list]        - list current registers\n"
134 	"set <reg> <type> <start> <size>   - set a register\n"
135 	"\t<type> is Uncacheable, Combine, Through, Protect, Back\n"
136 	"disable <reg>      - disable a register\n"
137 	"ensable <reg>      - enable a register"
138 );
139