mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-10-25 02:30:57 +00:00
186 lines
7.4 KiB
C
186 lines
7.4 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|
│ Copyright 2021 Justine Alexandra Roberts Tunney │
|
|
│ │
|
|
│ Permission to use, copy, modify, and/or distribute this software for │
|
|
│ any purpose with or without fee is hereby granted, provided that the │
|
|
│ above copyright notice and this permission notice appear in all copies. │
|
|
│ │
|
|
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
|
|
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
|
|
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
|
|
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
|
|
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
|
|
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
|
|
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
|
|
│ PERFORMANCE OF THIS SOFTWARE. │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/bits/bits.h"
|
|
#include "libc/dce.h"
|
|
#include "libc/macros.internal.h"
|
|
#include "libc/nt/efi.h"
|
|
#include "libc/nt/thunk/msabi.h"
|
|
#include "libc/runtime/e820.internal.h"
|
|
#include "libc/runtime/internal.h"
|
|
#include "libc/runtime/pc.internal.h"
|
|
#include "libc/runtime/runtime.h"
|
|
#include "libc/str/str.h"
|
|
|
|
/* TOOD: Why can't we change CR3? Could it really need PML5T? */
|
|
/* TOOD: Why does QEMU in UEFI mode take ten seconds to boot? */
|
|
|
|
struct EfiArgs {
|
|
char *Args[0x400 / sizeof(char *)];
|
|
char ArgBlock[0xC00];
|
|
};
|
|
|
|
static const EFI_GUID kEfiLoadedImageProtocol = LOADED_IMAGE_PROTOCOL;
|
|
|
|
/**
|
|
* EFI Application Entrypoint.
|
|
*
|
|
* This entrypoint is mutually exclusive from WinMain since
|
|
* Windows apps and EFI apps use the same PE binary format.
|
|
* So if you want to trade away Windows so that you can use
|
|
* UEFI instead of the normal BIOS boot process, do this:
|
|
*
|
|
* STATIC_YOINK("EfiMain");
|
|
* int main() { ... }
|
|
*
|
|
* You can use QEMU to test this, but please note that UEFI
|
|
* goes thousands of times slower than the normal BIOS boot
|
|
*
|
|
* qemu-system-x86_64 \
|
|
* -bios OVMF.fd \
|
|
* -nographic \
|
|
* -net none \
|
|
* -drive format=raw,file=fat:rw:o/tool/viz
|
|
* FS0:
|
|
* deathstar.com
|
|
*
|
|
* @see libc/dce.h
|
|
*/
|
|
__msabi noasan EFI_STATUS EfiMain(EFI_HANDLE ImageHandle,
|
|
EFI_SYSTEM_TABLE *SystemTable) {
|
|
int type, x87cw;
|
|
struct mman *mm;
|
|
uint32_t DescVersion;
|
|
uintptr_t i, j, MapSize;
|
|
struct EfiArgs *ArgBlock;
|
|
EFI_LOADED_IMAGE *ImgInfo;
|
|
EFI_MEMORY_DESCRIPTOR *Map;
|
|
uintptr_t Args, MapKey, DescSize;
|
|
uint64_t p, pe, cr4, *m, *pd, *sp, *pml4t, *pdt1, *pdt2, *pdpt1, *pdpt2;
|
|
extern char __os asm("__hostos");
|
|
|
|
__os = METAL;
|
|
|
|
/*
|
|
* Allocates and clears PC-compatible memory and copies image.
|
|
*/
|
|
SystemTable->BootServices->AllocatePages(
|
|
AllocateAddress, EfiConventionalMemory,
|
|
MAX(2 * 1024 * 1024, 1024 * 1024 + (_end - _base)) / 4096, 0);
|
|
SystemTable->BootServices->SetMem(0, 0x80000, 0);
|
|
SystemTable->BootServices->CopyMem((void *)(1024 * 1024), _base,
|
|
_end - _base);
|
|
|
|
/*
|
|
* Converts UEFI shell arguments to argv.
|
|
*/
|
|
ArgBlock = (struct EfiArgs *)0x7e000;
|
|
SystemTable->BootServices->HandleProtocol(ImageHandle,
|
|
&kEfiLoadedImageProtocol, &ImgInfo);
|
|
Args = GetDosArgv(ImgInfo->LoadOptions, ArgBlock->ArgBlock,
|
|
sizeof(ArgBlock->ArgBlock), ArgBlock->Args,
|
|
ARRAYLEN(ArgBlock->Args));
|
|
|
|
/*
|
|
* Asks UEFI which parts of our RAM we're allowed to use.
|
|
*/
|
|
Map = NULL;
|
|
MapSize = 0;
|
|
SystemTable->BootServices->GetMemoryMap(&MapSize, Map, &MapKey, &DescSize,
|
|
&DescVersion);
|
|
SystemTable->BootServices->AllocatePool(EfiLoaderData, MapSize, Map);
|
|
SystemTable->BootServices->GetMemoryMap(&MapSize, Map, &MapKey, &DescSize,
|
|
&DescVersion);
|
|
asm("xor\t%0,%0" : "=r"(mm)); /* gcc assumes null isn't mapped */
|
|
for (j = i = 0; i < MapSize / sizeof(EFI_MEMORY_DESCRIPTOR); ++i) {
|
|
if (Map[i].Type != EfiConventionalMemory) continue;
|
|
mm->e820[j].addr = Map[i].PhysicalStart;
|
|
mm->e820[j].size = Map[i].NumberOfPages * 4096;
|
|
mm->e820[j].type = kMemoryUsable;
|
|
++j;
|
|
}
|
|
SystemTable->BootServices->FreePool(Map);
|
|
|
|
/*
|
|
* Sets up page tables.
|
|
*/
|
|
pd = (uint64_t *)0x79000;
|
|
pdt1 = (uint64_t *)0x7b000;
|
|
pdt2 = (uint64_t *)0x7a000;
|
|
pdpt1 = (uint64_t *)0x7d000;
|
|
pdpt2 = (uint64_t *)0x7c000;
|
|
pml4t = (uint64_t *)0x7e000;
|
|
for (i = 0; i < 512; ++i) {
|
|
pd[i] = 0x1000 * i + PAGE_V + PAGE_RW;
|
|
}
|
|
pdt1[0] = (intptr_t)pd + PAGE_V + PAGE_RW;
|
|
pdt2[0] = (intptr_t)pd + PAGE_V + PAGE_RW;
|
|
pdpt1[0] = (intptr_t)pdt1 + PAGE_V + PAGE_RW;
|
|
pdpt2[0] = (intptr_t)pdt2 + PAGE_V + PAGE_RW;
|
|
pml4t[0] = (intptr_t)pdpt1 + PAGE_V + PAGE_RW;
|
|
pml4t[256] = (intptr_t)pdpt2 + PAGE_V + PAGE_RW;
|
|
__map_phdrs(mm, pml4t, 1024 * 1024);
|
|
|
|
/*
|
|
* Asks UEFI to handover control?
|
|
*/
|
|
SystemTable->BootServices->ExitBootServices(ImageHandle, MapKey);
|
|
|
|
/*
|
|
* Launches program.
|
|
*/
|
|
asm volatile("fldcw\t%3\n\t"
|
|
"mov\t%4,%%cr3\n\t"
|
|
".weak\tape_stack_vaddr\n\t"
|
|
".weak\tape_stack_memsz\n\t"
|
|
"movabs\t$ape_stack_vaddr,%%rsp\n\t"
|
|
"add\t$ape_stack_memsz,%%rsp\n\t"
|
|
"push\t$0\n\t" /* auxv[1][1] */
|
|
"push\t$0\n\t" /* auxv[1][0] */
|
|
"push\t(%1)\n\t" /* auxv[0][1] */
|
|
"push\t$31\n\t" /* auxv[0][0] AT_EXECFN */
|
|
"push\t$0\n\t" /* envp[0] */
|
|
"sub\t%2,%%rsp\n\t"
|
|
"mov\t%%rsp,%%rdi\n\t"
|
|
"rep movsb\n\t" /* argv */
|
|
"push\t%0\n\t" /* argc */
|
|
"xor\t%%edi,%%edi\n\t"
|
|
"xor\t%%eax,%%eax\n\t"
|
|
"xor\t%%ebx,%%ebx\n\t"
|
|
"xor\t%%ecx,%%ecx\n\t"
|
|
"xor\t%%edx,%%edx\n\t"
|
|
"xor\t%%edi,%%edi\n\t"
|
|
"xor\t%%esi,%%esi\n\t"
|
|
"xor\t%%ebp,%%ebp\n\t"
|
|
"xor\t%%r8d,%%r8d\n\t"
|
|
"xor\t%%r9d,%%r9d\n\t"
|
|
"xor\t%%r10d,%%r10d\n\t"
|
|
"xor\t%%r11d,%%r11d\n\t"
|
|
"xor\t%%r12d,%%r12d\n\t"
|
|
"xor\t%%r13d,%%r13d\n\t"
|
|
"xor\t%%r14d,%%r14d\n\t"
|
|
"xor\t%%r15d,%%r15d\n\t"
|
|
".weak\t_start\n\t"
|
|
"jmp\t_start"
|
|
: /* no outputs */
|
|
: "a"(Args), "S"(ArgBlock->Args), "c"((Args + 1) * 8),
|
|
"m"(x87cw), "r"(pml4t)
|
|
: "memory");
|
|
|
|
unreachable;
|
|
}
|