xref: /openbmc/u-boot/cmd/x86/mtrr.c (revision db00e921)
1 /*
2  * (C) Copyright 2014 Google, Inc
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <asm/msr.h>
9 #include <asm/mtrr.h>
10 
11 static const char *const mtrr_type_name[MTRR_TYPE_COUNT] = {
12 	"Uncacheable",
13 	"Combine",
14 	"2",
15 	"3",
16 	"Through",
17 	"Protect",
18 	"Back",
19 };
20 
21 static int do_mtrr_list(void)
22 {
23 	int i;
24 
25 	printf("Reg Valid Write-type   %-16s %-16s %-16s\n", "Base   ||",
26 	       "Mask   ||", "Size   ||");
27 	for (i = 0; i < MTRR_COUNT; i++) {
28 		const char *type = "Invalid";
29 		uint64_t base, mask, size;
30 		bool valid;
31 
32 		base = native_read_msr(MTRR_PHYS_BASE_MSR(i));
33 		mask = native_read_msr(MTRR_PHYS_MASK_MSR(i));
34 		size = ~mask & ((1ULL << CONFIG_CPU_ADDR_BITS) - 1);
35 		size |= (1 << 12) - 1;
36 		size += 1;
37 		valid = mask & MTRR_PHYS_MASK_VALID;
38 		type = mtrr_type_name[base & MTRR_BASE_TYPE_MASK];
39 		printf("%d   %-5s %-12s %016llx %016llx %016llx\n", i,
40 		       valid ? "Y" : "N", type, base & ~MTRR_BASE_TYPE_MASK,
41 		       mask & ~MTRR_PHYS_MASK_VALID, size);
42 	}
43 
44 	return 0;
45 }
46 
47 static int do_mtrr_set(uint reg, int argc, char * const argv[])
48 {
49 	const char *typename = argv[0];
50 	struct mtrr_state state;
51 	uint32_t start, size;
52 	uint64_t base, mask;
53 	int i, type = -1;
54 	bool valid;
55 
56 	if (argc < 3)
57 		return CMD_RET_USAGE;
58 	for (i = 0; i < MTRR_TYPE_COUNT; i++) {
59 		if (*typename == *mtrr_type_name[i])
60 			type = i;
61 	}
62 	if (type == -1) {
63 		printf("Invalid type name %s\n", typename);
64 		return CMD_RET_USAGE;
65 	}
66 	start = simple_strtoul(argv[1], NULL, 16);
67 	size = simple_strtoul(argv[2], NULL, 16);
68 
69 	base = start | type;
70 	valid = native_read_msr(MTRR_PHYS_MASK_MSR(reg)) & MTRR_PHYS_MASK_VALID;
71 	mask = ~((uint64_t)size - 1);
72 	mask &= (1ULL << CONFIG_CPU_ADDR_BITS) - 1;
73 	if (valid)
74 		mask |= MTRR_PHYS_MASK_VALID;
75 
76 	printf("base=%llx, mask=%llx\n", base, mask);
77 	mtrr_open(&state);
78 	wrmsrl(MTRR_PHYS_BASE_MSR(reg), base);
79 	wrmsrl(MTRR_PHYS_MASK_MSR(reg), mask);
80 	mtrr_close(&state);
81 
82 	return 0;
83 }
84 
85 static int mtrr_set_valid(int reg, bool valid)
86 {
87 	struct mtrr_state state;
88 	uint64_t mask;
89 
90 	mtrr_open(&state);
91 	mask = native_read_msr(MTRR_PHYS_MASK_MSR(reg));
92 	if (valid)
93 		mask |= MTRR_PHYS_MASK_VALID;
94 	else
95 		mask &= ~MTRR_PHYS_MASK_VALID;
96 	wrmsrl(MTRR_PHYS_MASK_MSR(reg), mask);
97 	mtrr_close(&state);
98 
99 	return 0;
100 }
101 
102 static int do_mtrr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
103 {
104 	const char *cmd;
105 	uint reg;
106 
107 	cmd = argv[1];
108 	if (argc < 2 || *cmd == 'l')
109 		return do_mtrr_list();
110 	argc -= 2;
111 	argv += 2;
112 	if (argc <= 0)
113 		return CMD_RET_USAGE;
114 	reg = simple_strtoul(argv[0], NULL, 16);
115 	if (reg >= MTRR_COUNT) {
116 		printf("Invalid register number\n");
117 		return CMD_RET_USAGE;
118 	}
119 	if (*cmd == 'e')
120 		return mtrr_set_valid(reg, true);
121 	else if (*cmd == 'd')
122 		return mtrr_set_valid(reg, false);
123 	else if (*cmd == 's')
124 		return do_mtrr_set(reg, argc - 1, argv + 1);
125 	else
126 		return CMD_RET_USAGE;
127 
128 	return 0;
129 }
130 
131 U_BOOT_CMD(
132 	mtrr,	6,	1,	do_mtrr,
133 	"Use x86 memory type range registers (32-bit only)",
134 	"[list]        - list current registers\n"
135 	"set <reg> <type> <start> <size>   - set a register\n"
136 	"\t<type> is Uncacheable, Combine, Through, Protect, Back\n"
137 	"disable <reg>      - disable a register\n"
138 	"ensable <reg>      - enable a register"
139 );
140