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#ifdef CONFIG_XEN_PV 24 __INIT 25ENTRY(startup_xen) 26 UNWIND_HINT_EMPTY 27 cld 28 29 /* Clear .bss */ 30 xor %eax,%eax 31 mov $__bss_start, %_ASM_DI 32 mov $__bss_stop, %_ASM_CX 33 sub %_ASM_DI, %_ASM_CX 34 shr $__ASM_SEL(2, 3), %_ASM_CX 35 rep __ASM_SIZE(stos) 36 37 mov %_ASM_SI, xen_start_info 38 mov $init_thread_union+THREAD_SIZE, %_ASM_SP 39 40#ifdef CONFIG_X86_64 41 /* Set up %gs. 42 * 43 * The base of %gs always points to fixed_percpu_data. If the 44 * stack protector canary is enabled, it is located at %gs:40. 45 * Note that, on SMP, the boot cpu uses init data section until 46 * the per cpu areas are set up. 47 */ 48 movl $MSR_GS_BASE,%ecx 49 movq $INIT_PER_CPU_VAR(fixed_percpu_data),%rax 50 cdq 51 wrmsr 52#endif 53 54 jmp xen_start_kernel 55END(startup_xen) 56 __FINIT 57#endif 58 59.pushsection .text 60 .balign PAGE_SIZE 61ENTRY(hypercall_page) 62 .rept (PAGE_SIZE / 32) 63 UNWIND_HINT_EMPTY 64 .skip 32 65 .endr 66 67#define HYPERCALL(n) \ 68 .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \ 69 .type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32 70#include <asm/xen-hypercalls.h> 71#undef HYPERCALL 72END(hypercall_page) 73.popsection 74 75 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux") 76 ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6") 77 ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0") 78#ifdef CONFIG_X86_32 79 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __PAGE_OFFSET) 80#else 81 ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, _ASM_PTR __START_KERNEL_map) 82 /* Map the p2m table to a 512GB-aligned user address. */ 83 ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M, .quad (PUD_SIZE * PTRS_PER_PUD)) 84#endif 85#ifdef CONFIG_XEN_PV 86 ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, _ASM_PTR startup_xen) 87#endif 88 ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page) 89 ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, 90 .ascii "!writable_page_tables|pae_pgdir_above_4gb") 91 ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES, 92 .long (1 << XENFEAT_writable_page_tables) | \ 93 (1 << XENFEAT_dom0) | \ 94 (1 << XENFEAT_linux_rsdp_unrestricted)) 95 ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes") 96 ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic") 97 ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID, 98 .quad _PAGE_PRESENT; .quad _PAGE_PRESENT) 99 ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1) 100 ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN, .long 1) 101 ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW, _ASM_PTR __HYPERVISOR_VIRT_START) 102 ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET, _ASM_PTR 0) 103 104#endif /*CONFIG_XEN */ 105