1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Xen-specific pieces of head.S, intended to
3 place in head.S */
4
5 #ifdef CONFIG_XEN
6
7 #include <linux/elfnote.h>
8 #include <linux/init.h>
9
10 #include <asm/boot.h>
11 #include <asm/asm.h>
12 #include <asm/msr.h>
13 #include <asm/page_types.h>
14 #include <asm/percpu.h>
15 #include <asm/unwind_hints.h>
16
17 #include <xen/interface/elfnote.h>
18 #include <xen/interface/features.h>
19 #include <xen/interface/xen.h>
20 #include <xen/interface/xen-mca.h>
21 #include <asm/xen/interface.h>
22
23 .pushsection .noinstr.text, "ax"
24 .balign PAGE_SIZE
25 SYM_CODE_START(hypercall_page)
26 .rept (PAGE_SIZE / 32)
27 UNWIND_HINT_FUNC
28 ANNOTATE_NOENDBR
29 ANNOTATE_UNRET_SAFE
30 ret
31 /*
32 * Xen will write the hypercal
33 */
34 .skip 31, 0xcc
35 .endr
36
37 #define HYPERCALL(n) \
38 .equ xen_hypercall_##n, hypercall_page
39 .type xen_hypercall_##n, @function; .s
40 #include <asm/xen-hypercalls.h>
41 #undef HYPERCALL
42 SYM_CODE_END(hypercall_page)
43 .popsection
44
45 #ifdef CONFIG_XEN_PV
46 __INIT
47 SYM_CODE_START(startup_xen)
48 UNWIND_HINT_END_OF_STACK
49 ANNOTATE_NOENDBR
50 cld
51
52 leaq __top_init_kernel_stack(%rip),
53
54 /* Set up %gs.
55 *
56 * The base of %gs always points to fi
57 * stack protector canary is enabled,
58 * Note that, on SMP, the boot cpu use
59 * the per cpu areas are set up.
60 */
61 movl $MSR_GS_BASE,%ecx
62 movq $INIT_PER_CPU_VAR(fixed_percpu
63 cdq
64 wrmsr
65
66 mov %rsi, %rdi
67 call xen_start_kernel
68 SYM_CODE_END(startup_xen)
69 __FINIT
70
71 #ifdef CONFIG_XEN_PV_SMP
72 .pushsection .text
73 SYM_CODE_START(asm_cpu_bringup_and_idle)
74 UNWIND_HINT_END_OF_STACK
75 ENDBR
76
77 call cpu_bringup_and_idle
78 SYM_CODE_END(asm_cpu_bringup_and_idle)
79
80 SYM_CODE_START(xen_cpu_bringup_again)
81 UNWIND_HINT_FUNC
82 mov %rdi, %rsp
83 UNWIND_HINT_REGS
84 call cpu_bringup_and_idle
85 SYM_CODE_END(xen_cpu_bringup_again)
86 .popsection
87 #endif
88 #endif
89
90 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS,
91 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION
92 ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION,
93 #ifdef CONFIG_XEN_PV
94 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE,
95 /* Map the p2m table to a 512GB-aligne
96 ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M,
97 ELFNOTE(Xen, XEN_ELFNOTE_ENTRY,
98 ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,
99 ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE,
100 ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID,
101 .quad _PAGE_PRESENT; .quad _PA
102 ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN
103 ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET,
104 # define FEATURES_PV (1 << XENFEAT_writable_pa
105 #else
106 # define FEATURES_PV 0
107 #endif
108 #ifdef CONFIG_XEN_PVH
109 # define FEATURES_PVH (1 << XENFEAT_linux_rsdp
110 #else
111 # define FEATURES_PVH 0
112 #endif
113 #ifdef CONFIG_XEN_DOM0
114 # define FEATURES_DOM0 (1 << XENFEAT_dom0)
115 #else
116 # define FEATURES_DOM0 0
117 #endif
118 ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAG
119 ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEA
120 .long FEATURES_PV | FEATURES_P
121 ELFNOTE(Xen, XEN_ELFNOTE_LOADER,
122 ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCE
123
124 #endif /*CONFIG_XEN */
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