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#include <console/console.h>
#include <arch/stages.h>
#include <payload_loader.h>
#include <ip_checksum.h>
#include <string.h>
/* When the ramstage is relocatable the elf loading ensures an elf image cannot
* be loaded over the ramstage code. */
static void jmp_payload_no_bounce_buffer(void *entry)
{
/* Jump to kernel */
__asm__ __volatile__(
" cld \n\t"
/* Now jump to the loaded image */
" call *%0\n\t"
/* The loaded image returned? */
" cli \n\t"
" cld \n\t"
::
"r" (entry)
);
}
static void jmp_payload(void *entry, unsigned long buffer, unsigned long size)
{
extern unsigned char _ram_seg, _eram_seg;
unsigned long lb_start, lb_size;
lb_start = (unsigned long)&_ram_seg;
lb_size = (unsigned long)(&_eram_seg - &_ram_seg);
printk(BIOS_SPEW, "entry = 0x%08lx\n", (unsigned long)entry);
printk(BIOS_SPEW, "lb_start = 0x%08lx\n", lb_start);
printk(BIOS_SPEW, "lb_size = 0x%08lx\n", lb_size);
printk(BIOS_SPEW, "buffer = 0x%08lx\n", buffer);
/* Jump to kernel */
__asm__ __volatile__(
" cld \n\t"
/* Save the callee save registers... */
" pushl %%esi\n\t"
" pushl %%edi\n\t"
" pushl %%ebx\n\t"
/* Save the parameters I was passed */
" pushl $0\n\t" /* 20 adjust */
" pushl %0\n\t" /* 16 lb_start */
" pushl %1\n\t" /* 12 buffer */
" pushl %2\n\t" /* 8 lb_size */
" pushl %3\n\t" /* 4 entry */
" pushl %4\n\t" /* 0 elf_boot_notes */
/* Compute the adjustment */
" xorl %%eax, %%eax\n\t"
" subl 16(%%esp), %%eax\n\t"
" addl 12(%%esp), %%eax\n\t"
" addl 8(%%esp), %%eax\n\t"
" movl %%eax, 20(%%esp)\n\t"
/* Place a copy of coreboot in its new location */
/* Move ``longs'' the coreboot size is 4 byte aligned */
" movl 12(%%esp), %%edi\n\t"
" addl 8(%%esp), %%edi\n\t"
" movl 16(%%esp), %%esi\n\t"
" movl 8(%%esp), %%ecx\n\n"
" shrl $2, %%ecx\n\t"
" rep movsl\n\t"
/* Adjust the stack pointer to point into the new coreboot image */
" addl 20(%%esp), %%esp\n\t"
/* Adjust the instruction pointer to point into the new coreboot image */
" movl $1f, %%eax\n\t"
" addl 20(%%esp), %%eax\n\t"
" jmp *%%eax\n\t"
"1: \n\t"
/* Copy the coreboot bounce buffer over coreboot */
/* Move ``longs'' the coreboot size is 4 byte aligned */
" movl 16(%%esp), %%edi\n\t"
" movl 12(%%esp), %%esi\n\t"
" movl 8(%%esp), %%ecx\n\t"
" shrl $2, %%ecx\n\t"
" rep movsl\n\t"
/* Now jump to the loaded image */
" movl %5, %%eax\n\t"
" movl 0(%%esp), %%ebx\n\t"
" call *4(%%esp)\n\t"
/* The loaded image returned? */
" cli \n\t"
" cld \n\t"
/* Copy the saved copy of coreboot where coreboot runs */
/* Move ``longs'' the coreboot size is 4 byte aligned */
" movl 16(%%esp), %%edi\n\t"
" movl 12(%%esp), %%esi\n\t"
" addl 8(%%esp), %%esi\n\t"
" movl 8(%%esp), %%ecx\n\t"
" shrl $2, %%ecx\n\t"
" rep movsl\n\t"
/* Adjust the stack pointer to point into the old coreboot image */
" subl 20(%%esp), %%esp\n\t"
/* Adjust the instruction pointer to point into the old coreboot image */
" movl $1f, %%eax\n\t"
" subl 20(%%esp), %%eax\n\t"
" jmp *%%eax\n\t"
"1: \n\t"
/* Drop the parameters I was passed */
" addl $24, %%esp\n\t"
/* Restore the callee save registers */
" popl %%ebx\n\t"
" popl %%edi\n\t"
" popl %%esi\n\t"
::
"ri" (lb_start), "ri" (buffer), "ri" (lb_size),
"ri" (entry),
"ri"(0), "ri" (0)
);
}
void arch_payload_run(const struct payload *payload)
{
if (IS_ENABLED(CONFIG_RELOCATABLE_RAMSTAGE))
jmp_payload_no_bounce_buffer(payload->entry);
else
jmp_payload(payload->entry, (uintptr_t)payload->bounce.data,
payload->bounce.size);
}
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