summaryrefslogtreecommitdiff
path: root/src/cpu/intel/smm/gen1/smmrelocate.c
blob: ae2440daab2cd0ba7b55f90bba5d4e933e30bab9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
/* SPDX-License-Identifier: GPL-2.0-only */

/* SMM relocation for i945-ivybridge. */

#include <assert.h>
#include <types.h>
#include <string.h>
#include <device/device.h>
#include <device/pci.h>
#include <commonlib/helpers.h>
#include <cpu/x86/mp.h>
#include <cpu/x86/msr.h>
#include <cpu/x86/mtrr.h>
#include <cpu/x86/smm.h>
#include <cpu/intel/em64t101_save_state.h>
#include <cpu/intel/smm_reloc.h>
#include <console/console.h>
#include <smp/node.h>

#define SMRR_SUPPORTED (1 << 11)

#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))

/* On model_6fx, model_1067x and model_106cx SMRR functions slightly
   differently. The MSR are at different location from the rest
   and need to be explicitly enabled in IA32_FEATURE_CONTROL MSR. */
bool cpu_has_alternative_smrr(void)
{
	struct cpuinfo_x86 c;
	get_fms(&c, cpuid_eax(1));
	if (c.x86 != 6)
		return false;
	switch (c.x86_model) {
	case 0xf:
	case 0x17: /* core2 */
	case 0x1c: /* Bonnell */
		return true;
	default:
		return false;
	}
}

static void write_smrr_alt(struct smm_relocation_params *relo_params)
{
	msr_t msr;
	msr = rdmsr(IA32_FEATURE_CONTROL);
	/* SMRR enabled and feature locked */
	if (!((msr.lo & SMRR_ENABLE)
			&& (msr.lo & FEATURE_CONTROL_LOCK_BIT))) {
		printk(BIOS_WARNING,
			"SMRR not enabled, skip writing SMRR...\n");
		return;
	}

	printk(BIOS_DEBUG, "Writing SMRR. base = 0x%08x, mask=0x%08x\n",
	       relo_params->smrr_base.lo, relo_params->smrr_mask.lo);

	wrmsr(MSR_SMRR_PHYS_BASE, relo_params->smrr_base);
	wrmsr(MSR_SMRR_PHYS_MASK, relo_params->smrr_mask);
}

static void fill_in_relocation_params(struct smm_relocation_params *params)
{
	uintptr_t tseg_base;
	size_t tseg_size;

	/* All range registers are aligned to 4KiB */
	const u32 rmask = ~((1 << 12) - 1);

	smm_region(&tseg_base, &tseg_size);

	if (!IS_ALIGNED(tseg_base, tseg_size)) {
		printk(BIOS_WARNING,
		       "TSEG base not aligned with TSEG SIZE! Not setting SMRR\n");
		return;
	}

	/* SMRR has 32-bits of valid address aligned to 4KiB. */
	params->smrr_base.lo = (tseg_base & rmask) | MTRR_TYPE_WRBACK;
	params->smrr_base.hi = 0;
	params->smrr_mask.lo = (~(tseg_size - 1) & rmask) | MTRR_PHYS_MASK_VALID;
	params->smrr_mask.hi = 0;

	/* On model_6fx and model_1067x bits [0:11] on smrr_base are reserved */
	if (cpu_has_alternative_smrr())
		params->smrr_base.lo &= rmask;

	smm_subregion(SMM_SUBREGION_CHIPSET, &params->ied_base, &params->ied_size);
}

static void setup_ied_area(struct smm_relocation_params *params)
{
	char *ied_base;

	struct ied_header ied = {
		.signature = "INTEL RSVD",
		.size = params->ied_size,
		.reserved = {0},
	};

	ied_base = (void *)params->ied_base;

	/* Place IED header at IEDBASE. */
	memcpy(ied_base, &ied, sizeof(ied));

	/* Zero out 32KiB at IEDBASE + 1MiB */
	memset(ied_base + (1 << 20), 0, (32 << 10));
}

void smm_lock(void)
{
	/* LOCK the SMM memory window and enable normal SMM.
	 * After running this function, only a full reset can
	 * make the SMM registers writable again.
	 */
	printk(BIOS_DEBUG, "Locking SMM.\n");

	northbridge_write_smram(D_LCK | G_SMRAME | C_BASE_SEG);
}

void smm_info(uintptr_t *perm_smbase, size_t *perm_smsize,
		size_t *smm_save_state_size)
{
	printk(BIOS_DEBUG, "Setting up SMI for CPU\n");

	fill_in_relocation_params(&smm_reloc_params);

	smm_subregion(SMM_SUBREGION_HANDLER, perm_smbase, perm_smsize);

	if (smm_reloc_params.ied_size)
		setup_ied_area(&smm_reloc_params);

	/* This may not be be correct for older CPU's supported by this code,
	   but given that em64t101_smm_state_save_area_t is larger than the
	   save_state of these CPU's it works. */
	*smm_save_state_size = sizeof(em64t101_smm_state_save_area_t);
}

void smm_initialize(void)
{
	/* Clear the SMM state in the southbridge. */
	smm_southbridge_clear_state();

	/*
	 * Run the relocation handler for on the BSP to check and set up
	 * parallel SMM relocation.
	 */
	smm_initiate_relocation();
}

/* The relocation work is actually performed in SMM context, but the code
 * resides in the ramstage module. This occurs by trampolining from the default
 * SMRAM entry point to here. */
void smm_relocation_handler(int cpu, uintptr_t curr_smbase,
				uintptr_t staggered_smbase)
{
	msr_t mtrr_cap;
	struct smm_relocation_params *relo_params = &smm_reloc_params;
	/* The em64t101 save state is sufficiently compatible with older
	   save states with regards of smbase, smm_revision. */
	em64t101_smm_state_save_area_t *save_state;
	u32 smbase = staggered_smbase;
	u32 iedbase = relo_params->ied_base;

	printk(BIOS_DEBUG, "In relocation handler: cpu %d\n", cpu);

	/* Make appropriate changes to the save state map. */
	if (relo_params->ied_size)
		printk(BIOS_DEBUG, "New SMBASE=0x%08x IEDBASE=0x%08x\n",
		       smbase, iedbase);
	else
		printk(BIOS_DEBUG, "New SMBASE=0x%08x\n",
		       smbase);

	save_state = (void *)(curr_smbase + SMM_DEFAULT_SIZE -
			sizeof(*save_state));
	save_state->smbase = smbase;

	printk(BIOS_SPEW, "SMM revision: 0x%08x\n", save_state->smm_revision);
	if (save_state->smm_revision == 0x00030101)
		save_state->iedbase = iedbase;

	/* Write EMRR and SMRR MSRs based on indicated support. */
	mtrr_cap = rdmsr(MTRR_CAP_MSR);
	if (!(mtrr_cap.lo & SMRR_SUPPORTED))
		return;

	if (cpu_has_alternative_smrr())
		write_smrr_alt(relo_params);
	else
		write_smrr(relo_params);
}

/*
 * The default SMM entry can happen in parallel or serially. If the
 * default SMM entry is done in parallel the BSP has already setup
 * the saving state to each CPU's MSRs. At least one save state size
 * is required for the initial SMM entry for the BSP to determine if
 * parallel SMM relocation is even feasible.
 */
void smm_relocate(void)
{
	/*
	 * If smm_save_state_in_msrs is non-zero then parallel SMM relocation
	 * shall take place. Run the relocation handler a second time on the
	 * BSP to do the final move. For APs, a relocation handler always
	 * needs to be run.
	 */
	if (!boot_cpu())
		smm_initiate_relocation();
}