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 .skip 31, 0x90 29 ret 30 .endr 31 32#define HYPERCALL(n) \ 33 .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \ 34 .type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32 35#include <asm/xen-hypercalls.h> 36#undef HYPERCALL 37SYM_CODE_END(hypercall_page) 38.popsection 39 40#ifdef CONFIG_XEN_PV 41 __INIT 42SYM_CODE_START(startup_xen) 43 UNWIND_HINT_EMPTY 44 cld 45 46 /* Clear .bss */ 47 xor %eax,%eax 48 mov $__bss_start, %rdi 49 mov $__bss_stop, %rcx 50 sub %rdi, %rcx 51 shr $3, %rcx 52 rep stosq 53 54 mov %rsi, xen_start_info 55 mov initial_stack(%rip), %rsp 56 57 /* Set up %gs. 58 * 59 * The base of %gs always points to fixed_percpu_data. If the 60 * stack protector canary is enabled, it is located at %gs:40. 61 * Note that, on SMP, the boot cpu uses init data section until 62 * the per cpu areas are set up. 63 */ 64 movl $MSR_GS_BASE,%ecx 65 movq $INIT_PER_CPU_VAR(fixed_percpu_data),%rax 66 cdq 67 wrmsr 68 69 call xen_start_kernel 70SYM_CODE_END(startup_xen) 71 __FINIT 72 73#ifdef CONFIG_XEN_PV_SMP 74.pushsection .text 75SYM_CODE_START(asm_cpu_bringup_and_idle) 76 UNWIND_HINT_EMPTY 77 78 call cpu_bringup_and_idle 79SYM_CODE_END(asm_cpu_bringup_and_idle) 80.popsection 81#endif 82#endif 83 84 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux") 85 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6") 86 ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0") 87#ifdef CONFIG_X86_32 88 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __PAGE_OFFSET) 89#else 90 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __START_KERNEL_map) 91 /* Map the p2m table to a 512GB-aligned user address. */ 92 ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M, .quad (PUD_SIZE * PTRS_PER_PUD)) 93#endif 94#ifdef CONFIG_XEN_PV 95 ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen) 96#endif 97 ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page) 98 ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, 99 .ascii "!writable_page_tables|pae_pgdir_above_4gb") 100 ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES, 101 .long (1 << XENFEAT_writable_page_tables) | \ 102 (1 << XENFEAT_dom0) | \ 103 (1 << XENFEAT_linux_rsdp_unrestricted)) 104 ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes") 105 ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic") 106 ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID, 107 .quad _PAGE_PRESENT; .quad _PAGE_PRESENT) 108 ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1) 109 ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN, .long 1) 110 ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW, _ASM_PTR __HYPERVISOR_VIRT_START) 111 ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET, _ASM_PTR 0) 112 113#endif /*CONFIG_XEN */ 114