grub/boot/sparc64/ieee1275/boot.S

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/* -*-Asm-*- */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/boot.h>
#include <grub/machine/boot.h>
.text
.align 4
.globl _start
_start:
/* OF CIF entry point arrives in %o4 */
pic_base:
call boot_continue
mov %o4, CIF_REG
. = _start + GRUB_BOOT_MACHINE_VER_MAJ
boot_version: .byte GRUB_BOOT_VERSION_MAJOR, GRUB_BOOT_VERSION_MINOR
/* The offsets to these locations are defined by the
* GRUB_BOOT_MACHINE_foo macros in include/grub/sparc/ieee1275/boot.h,
* and grub-setup uses this to patch these next three values as needed.
*
* The boot_path will be the OF device path of the partition where the
* rest of the GRUB kernel image resides. kernel_sector will be set to
* the location of the first block of the GRUB kernel, and
* kernel_address is the location where we should load that first block.
*
* After loading in that block we will execute it by jumping to the
* load address plus the size of the prepended A.OUT header (32 bytes).
*/
boot_path:
. = _start + GRUB_BOOT_MACHINE_KERNEL_SECTOR
kernel_sector: .xword 2
kernel_address: .word GRUB_BOOT_MACHINE_KERNEL_ADDR
prom_finddev_name: .asciz "finddevice"
prom_chosen_path: .asciz "/chosen"
prom_getprop_name: .asciz "getprop"
prom_stdout_name: .asciz "stdout"
prom_write_name: .asciz "write"
prom_bootpath_name: .asciz "bootpath"
prom_open_name: .asciz "open"
prom_seek_name: .asciz "seek"
prom_read_name: .asciz "read"
prom_exit_name: .asciz "exit"
grub_name: .asciz "GRUB "
#define GRUB_NAME_LEN 5
.align 4
prom_open_error:
GET_ABS(prom_open_name, %o2)
call console_write
mov 4, %o3
/* fallthru */
prom_error:
GET_ABS(prom_exit_name, %o0)
/* fallthru */
/* %o0: OF call name
* %o1: input arg 1
*/
prom_call_1_1:
mov 1, %g1
ba prom_call
mov 1, %o5
/* %o2: message string
* %o3: message length
*/
console_write:
GET_ABS(prom_write_name, %o0)
mov STDOUT_NODE_REG, %o1
/* fallthru */
/* %o0: OF call name
* %o1: input arg 1
* %o2: input arg 2
* %o3: input arg 3
*/
prom_call_3_1:
mov 3, %g1
mov 1, %o5
/* fallthru */
/* %o0: OF call name
* %g1: num inputs
* %o5: num outputs
* %o1-%o4: inputs
*/
prom_call:
stx %o0, [%l1 + 0x00]
stx %g1, [%l1 + 0x08]
stx %o5, [%l1 + 0x10]
stx %o1, [%l1 + 0x18]
stx %o2, [%l1 + 0x20]
stx %o3, [%l1 + 0x28]
stx %o4, [%l1 + 0x30]
jmpl CIF_REG, %g0
mov %l1, %o0
boot_continue:
mov %o7, PIC_REG /* PIC base */
sethi %hi(SCRATCH_PAD), %l1 /* OF argument slots */
/* Find the /chosen node so we can fetch the stdout handle,
* and thus perform console output.
*
* chosen_node = prom_finddevice("/chosen")
*/
GET_ABS(prom_finddev_name, %o0)
GET_ABS(prom_chosen_path, %o1)
call prom_call_1_1
clr %o2
ldx [%l1 + 0x20], CHOSEN_NODE_REG
brz CHOSEN_NODE_REG, prom_error
/* getprop(chosen_node, "stdout", &buffer, buffer_size) */
GET_ABS(prom_getprop_name, %o0)
mov 4, %g1
mov 1, %o5
mov CHOSEN_NODE_REG, %o1
GET_ABS(prom_stdout_name, %o2)
add %l1, 256, %o3
mov 1024, %o4
call prom_call
stx %g1, [%l1 + 256]
lduw [%l1 + 256], STDOUT_NODE_REG
brz,pn STDOUT_NODE_REG, prom_error
/* write(stdout_node, "GRUB ", strlen("GRUB ")) */
GET_ABS(grub_name, %o2)
call console_write
mov GRUB_NAME_LEN, %o3
/* Open up the boot_path, and use that handle to read the
* first block of the GRUB kernel image.
*
* bootdev_handle = open(boot_path)
*/
GET_ABS(prom_open_name, %o0)
GET_ABS(boot_path, %o1)
call prom_call_1_1
clr %o2
ldx [%l1 + 0x20], BOOTDEV_REG
brz,pn BOOTDEV_REG, prom_open_error
/* Since we have 64-bit cells, the high cell of the seek offset
* is zero and the low cell is the entire value.
*
* seek(bootdev, 0, *kernel_sector << 9)
*/
GET_ABS(prom_seek_name, %o0)
mov BOOTDEV_REG, %o1
clr %o2
LDX_ABS(kernel_sector, 0x00, %o3)
call prom_call_3_1
sllx %o3, 9, %o3
/* read(bootdev, *kernel_address, 512) */
GET_ABS(prom_read_name, %o0)
mov BOOTDEV_REG, %o1
LDUW_ABS(kernel_address, 0x00, %o2)
call prom_call_3_1
mov 512, %o3
LDUW_ABS(kernel_address, 0x00, %o2)
jmpl %o2, %o7
nop
1: ba,a 1b
. = _start + GRUB_BOOT_MACHINE_CODE_END
/* the last 4 bytes in the sector 0 contain the signature */
.word GRUB_BOOT_MACHINE_SIGNATURE