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1/* SPDX-License-Identifier: GPL-2.0 */
2/* Xen-specific pieces of head.S, intended to be included in the right
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
25SYM_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 hypercall page, and sort out ENDBR.
33 */
34 .skip 31, 0xcc
35 .endr
36
37#define HYPERCALL(n) \
38 .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \
39 .type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32
40#include <asm/xen-hypercalls.h>
41#undef HYPERCALL
42SYM_CODE_END(hypercall_page)
43.popsection
44
45#ifdef CONFIG_XEN_PV
46 __INIT
47SYM_CODE_START(startup_xen)
48 UNWIND_HINT_EMPTY
49 ANNOTATE_NOENDBR
50 cld
51
52 mov initial_stack(%rip), %rsp
53
54 /* Set up %gs.
55 *
56 * The base of %gs always points to fixed_percpu_data. If the
57 * stack protector canary is enabled, it is located at %gs:40.
58 * Note that, on SMP, the boot cpu uses init data section until
59 * the per cpu areas are set up.
60 */
61 movl $MSR_GS_BASE,%ecx
62 movq $INIT_PER_CPU_VAR(fixed_percpu_data),%rax
63 cdq
64 wrmsr
65
66 mov %rsi, %rdi
67 call xen_start_kernel
68SYM_CODE_END(startup_xen)
69 __FINIT
70
71#ifdef CONFIG_XEN_PV_SMP
72.pushsection .text
73SYM_CODE_START(asm_cpu_bringup_and_idle)
74 UNWIND_HINT_EMPTY
75 ENDBR
76
77 call cpu_bringup_and_idle
78SYM_CODE_END(asm_cpu_bringup_and_idle)
79.popsection
80#endif
81#endif
82
83 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux")
84 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6")
85 ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0")
86#ifdef CONFIG_X86_32
87 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __PAGE_OFFSET)
88#else
89 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __START_KERNEL_map)
90 /* Map the p2m table to a 512GB-aligned user address. */
91 ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M, .quad (PUD_SIZE * PTRS_PER_PUD))
92#endif
93#ifdef CONFIG_XEN_PV
94 ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen)
95#endif
96 ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page)
97 ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,
98 .ascii "!writable_page_tables|pae_pgdir_above_4gb")
99 ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES,
100 .long (1 << XENFEAT_writable_page_tables) | \
101 (1 << XENFEAT_dom0) | \
102 (1 << XENFEAT_linux_rsdp_unrestricted))
103 ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes")
104 ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic")
105 ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID,
106 .quad _PAGE_PRESENT; .quad _PAGE_PRESENT)
107 ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1)
108 ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN, .long 1)
109 ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW, _ASM_PTR __HYPERVISOR_VIRT_START)
110 ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET, _ASM_PTR 0)
111
112#endif /*CONFIG_XEN */
1/* SPDX-License-Identifier: GPL-2.0 */
2/* Xen-specific pieces of head.S, intended to be included in the right
3 place in head.S */
4
5#ifdef CONFIG_XEN
6
7#include <linux/elfnote.h>
8#include <linux/init.h>
9#include <linux/instrumentation.h>
10
11#include <asm/boot.h>
12#include <asm/asm.h>
13#include <asm/frame.h>
14#include <asm/msr.h>
15#include <asm/page_types.h>
16#include <asm/percpu.h>
17#include <asm/unwind_hints.h>
18
19#include <xen/interface/elfnote.h>
20#include <xen/interface/features.h>
21#include <xen/interface/xen.h>
22#include <xen/interface/xen-mca.h>
23#include <asm/xen/interface.h>
24
25#ifdef CONFIG_XEN_PV
26 __INIT
27SYM_CODE_START(startup_xen)
28 UNWIND_HINT_END_OF_STACK
29 ANNOTATE_NOENDBR
30 cld
31
32 leaq __top_init_kernel_stack(%rip), %rsp
33
34 /* Set up %gs.
35 *
36 * The base of %gs always points to fixed_percpu_data. If the
37 * stack protector canary is enabled, it is located at %gs:40.
38 * Note that, on SMP, the boot cpu uses init data section until
39 * the per cpu areas are set up.
40 */
41 movl $MSR_GS_BASE,%ecx
42 movq $INIT_PER_CPU_VAR(fixed_percpu_data),%rax
43 cdq
44 wrmsr
45
46 mov %rsi, %rdi
47 call xen_start_kernel
48SYM_CODE_END(startup_xen)
49 __FINIT
50
51#ifdef CONFIG_XEN_PV_SMP
52.pushsection .text
53SYM_CODE_START(asm_cpu_bringup_and_idle)
54 UNWIND_HINT_END_OF_STACK
55 ENDBR
56
57 call cpu_bringup_and_idle
58SYM_CODE_END(asm_cpu_bringup_and_idle)
59
60SYM_CODE_START(xen_cpu_bringup_again)
61 UNWIND_HINT_FUNC
62 mov %rdi, %rsp
63 UNWIND_HINT_REGS
64 call cpu_bringup_and_idle
65SYM_CODE_END(xen_cpu_bringup_again)
66.popsection
67#endif
68#endif
69
70 .pushsection .noinstr.text, "ax"
71/*
72 * Xen hypercall interface to the hypervisor.
73 *
74 * Input:
75 * %eax: hypercall number
76 * 32-bit:
77 * %ebx, %ecx, %edx, %esi, %edi: args 1..5 for the hypercall
78 * 64-bit:
79 * %rdi, %rsi, %rdx, %r10, %r8: args 1..5 for the hypercall
80 * Output: %[er]ax
81 */
82SYM_FUNC_START(xen_hypercall_hvm)
83 ENDBR
84 FRAME_BEGIN
85 /* Save all relevant registers (caller save and arguments). */
86#ifdef CONFIG_X86_32
87 push %eax
88 push %ebx
89 push %ecx
90 push %edx
91 push %esi
92 push %edi
93#else
94 push %rax
95 push %rcx
96 push %rdx
97 push %rdi
98 push %rsi
99 push %r11
100 push %r10
101 push %r9
102 push %r8
103#ifdef CONFIG_FRAME_POINTER
104 pushq $0 /* Dummy push for stack alignment. */
105#endif
106#endif
107 /* Set the vendor specific function. */
108 call __xen_hypercall_setfunc
109 /* Set ZF = 1 if AMD, Restore saved registers. */
110#ifdef CONFIG_X86_32
111 lea xen_hypercall_amd, %ebx
112 cmp %eax, %ebx
113 pop %edi
114 pop %esi
115 pop %edx
116 pop %ecx
117 pop %ebx
118 pop %eax
119#else
120 lea xen_hypercall_amd(%rip), %rcx
121 cmp %rax, %rcx
122#ifdef CONFIG_FRAME_POINTER
123 pop %rax /* Dummy pop. */
124#endif
125 pop %r8
126 pop %r9
127 pop %r10
128 pop %r11
129 pop %rsi
130 pop %rdi
131 pop %rdx
132 pop %rcx
133 pop %rax
134#endif
135 FRAME_END
136 /* Use correct hypercall function. */
137 jz xen_hypercall_amd
138 jmp xen_hypercall_intel
139SYM_FUNC_END(xen_hypercall_hvm)
140
141SYM_FUNC_START(xen_hypercall_amd)
142 vmmcall
143 RET
144SYM_FUNC_END(xen_hypercall_amd)
145
146SYM_FUNC_START(xen_hypercall_intel)
147 vmcall
148 RET
149SYM_FUNC_END(xen_hypercall_intel)
150 .popsection
151
152 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux")
153 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6")
154 ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0")
155#ifdef CONFIG_XEN_PV
156 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __START_KERNEL_map)
157 /* Map the p2m table to a 512GB-aligned user address. */
158 ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M, .quad (PUD_SIZE * PTRS_PER_PUD))
159 ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, .globl xen_elfnote_entry;
160 xen_elfnote_entry: _ASM_PTR xen_elfnote_entry_value - .)
161 ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .ascii "!writable_page_tables")
162 ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes")
163 ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID,
164 .quad _PAGE_PRESENT; .quad _PAGE_PRESENT)
165 ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN, .long 1)
166 ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET, _ASM_PTR 0)
167# define FEATURES_PV (1 << XENFEAT_writable_page_tables)
168#else
169# define FEATURES_PV 0
170#endif
171#ifdef CONFIG_XEN_PVH
172# define FEATURES_PVH (1 << XENFEAT_linux_rsdp_unrestricted)
173#else
174# define FEATURES_PVH 0
175#endif
176#ifdef CONFIG_XEN_DOM0
177# define FEATURES_DOM0 (1 << XENFEAT_dom0)
178#else
179# define FEATURES_DOM0 0
180#endif
181 ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES,
182 .long FEATURES_PV | FEATURES_PVH | FEATURES_DOM0)
183 ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic")
184 ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1)
185
186#endif /*CONFIG_XEN */