arch/x86/xen/xen-head.S

   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/page_types.h>
  13
  14 #include <xen/interface/elfnote.h>
  15 #include <xen/interface/features.h>
  16 #include <xen/interface/xen.h>
  17 #include <xen/interface/xen-mca.h>
  18 #include <asm/xen/interface.h>
  19
  20 #ifdef CONFIG_XEN_PV
  21         __INIT
  22 ENTRY(startup_xen)
  23         cld
  24
  25         /* Clear .bss */
  26         xor %eax,%eax
  27         mov $__bss_start, %_ASM_DI
  28         mov $__bss_stop, %_ASM_CX
  29         sub %_ASM_DI, %_ASM_CX
  30         shr $__ASM_SEL(2, 3), %_ASM_CX
  31         rep __ASM_SIZE(stos)
  32
  33         mov %_ASM_SI, xen_start_info
  34         mov $init_thread_union+THREAD_SIZE, %_ASM_SP
  35
  36         jmp xen_start_kernel
  37
  38         __FINIT
  39 #endif
  40
  41 .pushsection .text
  42         .balign PAGE_SIZE
  43 ENTRY(hypercall_page)
  44         .skip PAGE_SIZE
  45
  46 #define HYPERCALL(n) \
  47         .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \
  48         .type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32
  49 #include <asm/xen-hypercalls.h>
  50 #undef HYPERCALL
  51
  52 .popsection
  53
  54         ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS,       .asciz "linux")
  55         ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION,  .asciz "2.6")
  56         ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION,    .asciz "xen-3.0")
  57 #ifdef CONFIG_X86_32
  58         ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE,      _ASM_PTR __PAGE_OFFSET)
  59 #else
  60         ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE,      _ASM_PTR __START_KERNEL_map)
  61         /* Map the p2m table to a 512GB-aligned user address. */
  62         ELFNOTE(Xen, XEN_ELFNOTE_INIT_P2M,       .quad (PUD_SIZE * PTRS_PER_PUD))
  63 #endif
  64 #ifdef CONFIG_XEN_PV
  65         ELFNOTE(Xen, XEN_ELFNOTE_ENTRY,          _ASM_PTR startup_xen)
  66 #endif
  67         ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, _ASM_PTR hypercall_page)
  68         ELFNOTE(Xen, XEN_ELFNOTE_FEATURES,
  69                 .ascii "!writable_page_tables|pae_pgdir_above_4gb")
  70         ELFNOTE(Xen, XEN_ELFNOTE_SUPPORTED_FEATURES,
  71                 .long (1 << XENFEAT_writable_page_tables) | (1 << XENFEAT_dom0))
  72         ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE,       .asciz "yes")
  73         ELFNOTE(Xen, XEN_ELFNOTE_LOADER,         .asciz "generic")
  74         ELFNOTE(Xen, XEN_ELFNOTE_L1_MFN_VALID,
  75                 .quad _PAGE_PRESENT; .quad _PAGE_PRESENT)
  76         ELFNOTE(Xen, XEN_ELFNOTE_SUSPEND_CANCEL, .long 1)
  77         ELFNOTE(Xen, XEN_ELFNOTE_MOD_START_PFN,  .long 1)
  78         ELFNOTE(Xen, XEN_ELFNOTE_HV_START_LOW,   _ASM_PTR __HYPERVISOR_VIRT_START)
  79         ELFNOTE(Xen, XEN_ELFNOTE_PADDR_OFFSET,   _ASM_PTR 0)
  80
  81 #endif /*CONFIG_XEN */