1 | // SPDX-License-Identifier: GPL-2.0 |
---|---|
2 | #include <linux/acpi.h> |
3 | |
4 | #include <xen/hvc-console.h> |
5 | |
6 | #include <asm/bootparam.h> |
7 | #include <asm/io_apic.h> |
8 | #include <asm/hypervisor.h> |
9 | #include <asm/e820/api.h> |
10 | #include <asm/x86_init.h> |
11 | |
12 | #include <asm/xen/interface.h> |
13 | |
14 | #include <xen/xen.h> |
15 | #include <xen/interface/hvm/start_info.h> |
16 | |
17 | /* |
18 | * PVH variables. |
19 | * |
20 | * pvh_bootparams and pvh_start_info need to live in a data segment since |
21 | * they are used after startup_{32|64}, which clear .bss, are invoked. |
22 | */ |
23 | struct boot_params __initdata pvh_bootparams; |
24 | struct hvm_start_info __initdata pvh_start_info; |
25 | |
26 | const unsigned int __initconst pvh_start_info_sz = sizeof(pvh_start_info); |
27 | |
28 | static u64 __init pvh_get_root_pointer(void) |
29 | { |
30 | return pvh_start_info.rsdp_paddr; |
31 | } |
32 | |
33 | /* |
34 | * Xen guests are able to obtain the memory map from the hypervisor via the |
35 | * HYPERVISOR_memory_op hypercall. |
36 | * If we are trying to boot a Xen PVH guest, it is expected that the kernel |
37 | * will have been configured to provide an override for this routine to do |
38 | * just that. |
39 | */ |
40 | void __init __weak mem_map_via_hcall(struct boot_params *ptr __maybe_unused) |
41 | { |
42 | xen_raw_printk(fmt: "Error: Could not find memory map\n"); |
43 | BUG(); |
44 | } |
45 | |
46 | static void __init init_pvh_bootparams(bool xen_guest) |
47 | { |
48 | if ((pvh_start_info.version > 0) && (pvh_start_info.memmap_entries)) { |
49 | struct hvm_memmap_table_entry *ep; |
50 | int i; |
51 | |
52 | ep = __va(pvh_start_info.memmap_paddr); |
53 | pvh_bootparams.e820_entries = pvh_start_info.memmap_entries; |
54 | |
55 | for (i = 0; i < pvh_bootparams.e820_entries ; i++, ep++) { |
56 | pvh_bootparams.e820_table[i].addr = ep->addr; |
57 | pvh_bootparams.e820_table[i].size = ep->size; |
58 | pvh_bootparams.e820_table[i].type = ep->type; |
59 | } |
60 | } else if (xen_guest) { |
61 | mem_map_via_hcall(ptr: &pvh_bootparams); |
62 | } else { |
63 | /* Non-xen guests are not supported by version 0 */ |
64 | BUG(); |
65 | } |
66 | |
67 | if (pvh_bootparams.e820_entries < E820_MAX_ENTRIES_ZEROPAGE - 1) { |
68 | pvh_bootparams.e820_table[pvh_bootparams.e820_entries].addr = |
69 | ISA_START_ADDRESS; |
70 | pvh_bootparams.e820_table[pvh_bootparams.e820_entries].size = |
71 | ISA_END_ADDRESS - ISA_START_ADDRESS; |
72 | pvh_bootparams.e820_table[pvh_bootparams.e820_entries].type = |
73 | E820_TYPE_RESERVED; |
74 | pvh_bootparams.e820_entries++; |
75 | } else |
76 | xen_raw_printk(fmt: "Warning: Can fit ISA range into e820\n"); |
77 | |
78 | if (xen_guest) |
79 | xen_reserve_extra_memory(bootp: &pvh_bootparams); |
80 | |
81 | pvh_bootparams.hdr.cmd_line_ptr = |
82 | pvh_start_info.cmdline_paddr; |
83 | |
84 | /* The first module is always ramdisk. */ |
85 | if (pvh_start_info.nr_modules) { |
86 | struct hvm_modlist_entry *modaddr = |
87 | __va(pvh_start_info.modlist_paddr); |
88 | pvh_bootparams.hdr.ramdisk_image = modaddr->paddr; |
89 | pvh_bootparams.hdr.ramdisk_size = modaddr->size; |
90 | } |
91 | |
92 | /* |
93 | * See Documentation/arch/x86/boot.rst. |
94 | * |
95 | * Version 2.12 supports Xen entry point but we will use default x86/PC |
96 | * environment (i.e. hardware_subarch 0). |
97 | */ |
98 | pvh_bootparams.hdr.version = (2 << 8) | 12; |
99 | pvh_bootparams.hdr.type_of_loader = ((xen_guest ? 0x9 : 0xb) << 4) | 0; |
100 | |
101 | x86_init.acpi.get_root_pointer = pvh_get_root_pointer; |
102 | } |
103 | |
104 | /* |
105 | * If we are trying to boot a Xen PVH guest, it is expected that the kernel |
106 | * will have been configured to provide the required override for this routine. |
107 | */ |
108 | void __init __weak xen_pvh_init(struct boot_params *boot_params) |
109 | { |
110 | xen_raw_printk(fmt: "Error: Missing xen PVH initialization\n"); |
111 | BUG(); |
112 | } |
113 | |
114 | static void __init hypervisor_specific_init(bool xen_guest) |
115 | { |
116 | if (xen_guest) |
117 | xen_pvh_init(boot_params: &pvh_bootparams); |
118 | } |
119 | |
120 | /* |
121 | * This routine (and those that it might call) should not use |
122 | * anything that lives in .bss since that segment will be cleared later. |
123 | */ |
124 | void __init xen_prepare_pvh(void) |
125 | { |
126 | |
127 | u32 msr = xen_cpuid_base(); |
128 | bool xen_guest = !!msr; |
129 | |
130 | if (pvh_start_info.magic != XEN_HVM_START_MAGIC_VALUE) { |
131 | xen_raw_printk(fmt: "Error: Unexpected magic value (0x%08x)\n", |
132 | pvh_start_info.magic); |
133 | BUG(); |
134 | } |
135 | |
136 | memset(&pvh_bootparams, 0, sizeof(pvh_bootparams)); |
137 | |
138 | hypervisor_specific_init(xen_guest); |
139 | |
140 | init_pvh_bootparams(xen_guest); |
141 | } |
142 |