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 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 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 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 (__end_init_task - PTREGS_SIZE)(%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 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, .asciz "linux") 91 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6") 92 ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0") 93 #ifdef CONFIG_XEN_PV 94 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __START_KERNEL_map) 95 /* Map the p2m table to a 512GB-aligned user address. */ 96 ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M, .quad (PUD_SIZE * PTRS_PER_PUD)) 97 ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen) 98 ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .ascii "!writable_page_tables") 99 ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes") 100 ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID, 101 .quad _PAGE_PRESENT; .quad _PAGE_PRESENT) 102 ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN, .long 1) 103 ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET, _ASM_PTR 0) 104 # define FEATURES_PV (1 << XENFEAT_writable_page_tables) 105 #else 106 # define FEATURES_PV 0 107 #endif 108 #ifdef CONFIG_XEN_PVH 109 # define FEATURES_PVH (1 << XENFEAT_linux_rsdp_unrestricted) 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_PAGE, _ASM_PTR hypercall_page) 119 ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES, 120 .long FEATURES_PV | FEATURES_PVH | FEATURES_DOM0) 121 ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic") 122 ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1) 123 124 #endif /*CONFIG_XEN */ 125