xref: /openbmc/qemu/hw/i386/fw_cfg.c (revision 0b84b662)
1 /*
2  * QEMU fw_cfg helpers (X86 specific)
3  *
4  * Copyright (c) 2019 Red Hat, Inc.
5  *
6  * Author:
7  *   Philippe Mathieu-Daudé <philmd@redhat.com>
8  *
9  * SPDX-License-Identifier: GPL-2.0-or-later
10  *
11  * This work is licensed under the terms of the GNU GPL, version 2 or later.
12  * See the COPYING file in the top-level directory.
13  */
14 
15 #include "qemu/osdep.h"
16 #include "sysemu/numa.h"
17 #include "hw/acpi/acpi.h"
18 #include "hw/firmware/smbios.h"
19 #include "hw/i386/pc.h"
20 #include "hw/i386/fw_cfg.h"
21 #include "hw/timer/hpet.h"
22 #include "hw/nvram/fw_cfg.h"
23 #include "e820_memory_layout.h"
24 #include "kvm_i386.h"
25 
26 const char *fw_cfg_arch_key_name(uint16_t key)
27 {
28     static const struct {
29         uint16_t key;
30         const char *name;
31     } fw_cfg_arch_wellknown_keys[] = {
32         {FW_CFG_ACPI_TABLES, "acpi_tables"},
33         {FW_CFG_SMBIOS_ENTRIES, "smbios_entries"},
34         {FW_CFG_IRQ0_OVERRIDE, "irq0_override"},
35         {FW_CFG_E820_TABLE, "e820_table"},
36         {FW_CFG_HPET, "hpet"},
37     };
38 
39     for (size_t i = 0; i < ARRAY_SIZE(fw_cfg_arch_wellknown_keys); i++) {
40         if (fw_cfg_arch_wellknown_keys[i].key == key) {
41             return fw_cfg_arch_wellknown_keys[i].name;
42         }
43     }
44     return NULL;
45 }
46 
47 void fw_cfg_build_smbios(MachineState *ms, FWCfgState *fw_cfg)
48 {
49     uint8_t *smbios_tables, *smbios_anchor;
50     size_t smbios_tables_len, smbios_anchor_len;
51     struct smbios_phys_mem_area *mem_array;
52     unsigned i, array_count;
53     X86CPU *cpu = X86_CPU(ms->possible_cpus->cpus[0].cpu);
54 
55     /* tell smbios about cpuid version and features */
56     smbios_set_cpuid(cpu->env.cpuid_version, cpu->env.features[FEAT_1_EDX]);
57 
58     smbios_tables = smbios_get_table_legacy(ms, &smbios_tables_len);
59     if (smbios_tables) {
60         fw_cfg_add_bytes(fw_cfg, FW_CFG_SMBIOS_ENTRIES,
61                          smbios_tables, smbios_tables_len);
62     }
63 
64     /* build the array of physical mem area from e820 table */
65     mem_array = g_malloc0(sizeof(*mem_array) * e820_get_num_entries());
66     for (i = 0, array_count = 0; i < e820_get_num_entries(); i++) {
67         uint64_t addr, len;
68 
69         if (e820_get_entry(i, E820_RAM, &addr, &len)) {
70             mem_array[array_count].address = addr;
71             mem_array[array_count].length = len;
72             array_count++;
73         }
74     }
75     smbios_get_tables(ms, mem_array, array_count,
76                       &smbios_tables, &smbios_tables_len,
77                       &smbios_anchor, &smbios_anchor_len);
78     g_free(mem_array);
79 
80     if (smbios_anchor) {
81         fw_cfg_add_file(fw_cfg, "etc/smbios/smbios-tables",
82                         smbios_tables, smbios_tables_len);
83         fw_cfg_add_file(fw_cfg, "etc/smbios/smbios-anchor",
84                         smbios_anchor, smbios_anchor_len);
85     }
86 }
87 
88 FWCfgState *fw_cfg_arch_create(MachineState *ms,
89                                       uint16_t boot_cpus,
90                                       uint16_t apic_id_limit)
91 {
92     FWCfgState *fw_cfg;
93     uint64_t *numa_fw_cfg;
94     int i;
95     MachineClass *mc = MACHINE_GET_CLASS(ms);
96     const CPUArchIdList *cpus = mc->possible_cpu_arch_ids(ms);
97     int nb_numa_nodes = ms->numa_state->num_nodes;
98 
99     fw_cfg = fw_cfg_init_io_dma(FW_CFG_IO_BASE, FW_CFG_IO_BASE + 4,
100                                 &address_space_memory);
101     fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, boot_cpus);
102 
103     /* FW_CFG_MAX_CPUS is a bit confusing/problematic on x86:
104      *
105      * For machine types prior to 1.8, SeaBIOS needs FW_CFG_MAX_CPUS for
106      * building MPTable, ACPI MADT, ACPI CPU hotplug and ACPI SRAT table,
107      * that tables are based on xAPIC ID and QEMU<->SeaBIOS interface
108      * for CPU hotplug also uses APIC ID and not "CPU index".
109      * This means that FW_CFG_MAX_CPUS is not the "maximum number of CPUs",
110      * but the "limit to the APIC ID values SeaBIOS may see".
111      *
112      * So for compatibility reasons with old BIOSes we are stuck with
113      * "etc/max-cpus" actually being apic_id_limit
114      */
115     fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, apic_id_limit);
116     fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size);
117     fw_cfg_add_bytes(fw_cfg, FW_CFG_ACPI_TABLES,
118                      acpi_tables, acpi_tables_len);
119     fw_cfg_add_i32(fw_cfg, FW_CFG_IRQ0_OVERRIDE, kvm_allows_irq0_override());
120 
121     fw_cfg_add_bytes(fw_cfg, FW_CFG_E820_TABLE,
122                      &e820_reserve, sizeof(e820_reserve));
123     fw_cfg_add_file(fw_cfg, "etc/e820", e820_table,
124                     sizeof(struct e820_entry) * e820_get_num_entries());
125 
126     fw_cfg_add_bytes(fw_cfg, FW_CFG_HPET, &hpet_cfg, sizeof(hpet_cfg));
127     /* allocate memory for the NUMA channel: one (64bit) word for the number
128      * of nodes, one word for each VCPU->node and one word for each node to
129      * hold the amount of memory.
130      */
131     numa_fw_cfg = g_new0(uint64_t, 1 + apic_id_limit + nb_numa_nodes);
132     numa_fw_cfg[0] = cpu_to_le64(nb_numa_nodes);
133     for (i = 0; i < cpus->len; i++) {
134         unsigned int apic_id = cpus->cpus[i].arch_id;
135         assert(apic_id < apic_id_limit);
136         numa_fw_cfg[apic_id + 1] = cpu_to_le64(cpus->cpus[i].props.node_id);
137     }
138     for (i = 0; i < nb_numa_nodes; i++) {
139         numa_fw_cfg[apic_id_limit + 1 + i] =
140             cpu_to_le64(ms->numa_state->nodes[i].node_mem);
141     }
142     fw_cfg_add_bytes(fw_cfg, FW_CFG_NUMA, numa_fw_cfg,
143                      (1 + apic_id_limit + nb_numa_nodes) *
144                      sizeof(*numa_fw_cfg));
145 
146     return fw_cfg;
147 }
148 
149 void fw_cfg_build_feature_control(MachineState *ms, FWCfgState *fw_cfg)
150 {
151     X86CPU *cpu = X86_CPU(ms->possible_cpus->cpus[0].cpu);
152     CPUX86State *env = &cpu->env;
153     uint32_t unused, ecx, edx;
154     uint64_t feature_control_bits = 0;
155     uint64_t *val;
156 
157     cpu_x86_cpuid(env, 1, 0, &unused, &unused, &ecx, &edx);
158     if (ecx & CPUID_EXT_VMX) {
159         feature_control_bits |= FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX;
160     }
161 
162     if ((edx & (CPUID_EXT2_MCE | CPUID_EXT2_MCA)) ==
163         (CPUID_EXT2_MCE | CPUID_EXT2_MCA) &&
164         (env->mcg_cap & MCG_LMCE_P)) {
165         feature_control_bits |= FEATURE_CONTROL_LMCE;
166     }
167 
168     if (!feature_control_bits) {
169         return;
170     }
171 
172     val = g_malloc(sizeof(*val));
173     *val = cpu_to_le64(feature_control_bits | FEATURE_CONTROL_LOCKED);
174     fw_cfg_add_file(fw_cfg, "etc/msr_feature_control", val, sizeof(*val));
175 }
176