firmware: Handle overlapping load and link addresses in relocation

This patch extends relocation to handle overlapping load and link
addresses.

The updated relocation will work fine in most cases except when the
relocate copy loop itself falls in overlapping load and link addresses.

Signed-off-by: Xiang W <wxjstz@126.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
This commit is contained in:
Xiang W 2019-06-13 12:53:12 +05:30 committed by Anup Patel
parent 331f291e4c
commit a5b37bd7d2

View file

@ -27,6 +27,17 @@
add \__d4, \__s4, zero
.endm
/*
* If __start_reg <= __check_reg and __check_reg < __end_reg then
* jump to __pass
*/
.macro BRANGE __start_reg, __end_reg, __check_reg, __jump_lable
blt \__check_reg, \__start_reg, 999f
bge \__check_reg, \__end_reg, 999f
j \__jump_lable
999:
.endm
.align 3
.section .entry, "ax", %progbits
.globl _start
@ -45,22 +56,51 @@ _start:
REG_S t1, 0(t0)
/* Relocate if load address != link address */
_relocate:
la t0, _link_start
REG_L t0, 0(t0)
la t1, _link_end
REG_L t1, 0(t1)
la t2, _load_start
REG_L t2, 0(t2)
sub t3, t1, t0
add t3, t3, t2
beq t0, t2, _relocate_done
la t4, _relocate_done
sub t4, t4, t2
add t4, t4, t0
_relocate_copy:
blt t2, t0, _relocate_copy_to_upper
_relocate_copy_to_lower:
ble t1, t2, _relocate_copy_to_lower_loop
la t3, _boot_hart_done
BRANGE t2, t1, t3, _start_hang
la t3, _relocate
la t5, _relocate_done
BRANGE t2, t1, t3, _start_hang
BRANGE t2, t1, t5, _start_hang
BRANGE t3, t5, t2, _start_hang
_relocate_copy_to_lower_loop:
REG_L t3, 0(t2)
REG_S t3, 0(t0)
add t0, t0, __SIZEOF_POINTER__
add t2, t2, __SIZEOF_POINTER__
blt t0, t1, _relocate_copy
blt t0, t1, _relocate_copy_to_lower_loop
jr t4
_relocate_copy_to_upper:
ble t3, t0, _relocate_copy_to_upper_loop
la t2, _boot_hart_done
BRANGE t0, t3, t2, _start_hang
la t2, _relocate
la t5, _relocate_done
BRANGE t0, t3, t2, _start_hang
BRANGE t0, t3, t5, _start_hang
BRANGE t2, t5, t0, _start_hang
_relocate_copy_to_upper_loop:
add t3, t3, -__SIZEOF_POINTER__
add t1, t1, -__SIZEOF_POINTER__
REG_L t2, 0(t3)
REG_S t2, 0(t1)
blt t0, t1, _relocate_copy_to_upper_loop
jr t4
_relocate_done: