You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
68 lines
2.1 KiB
68 lines
2.1 KiB
![]()
1 year ago
|
.syntax unified
|
||
|
|
||
|
.text
|
||
|
|
||
|
.global reset_handler
|
||
|
.type reset_handler, STT_FUNC
|
||
|
reset_handler:
|
||
|
// setup environment for subsequent stage of code
|
||
|
ldr r2, =0 // r2 - the word-sized value to be written
|
||
|
|
||
|
ldr r0, =sram1_start // r0 - point to beginning of SRAM
|
||
|
ldr r1, =sram1_end // r1 - point to byte after the end of SRAM
|
||
|
bl memset_reg
|
||
|
|
||
|
ldr r0, =sram2_start // r0 - point to beginning of SRAM
|
||
|
ldr r1, =sram2_end // r1 - point to byte after the end of SRAM
|
||
|
bl memset_reg
|
||
|
|
||
|
ldr r0, =sram4_start // r0 - point to beginning of SRAM
|
||
|
ldr r1, =sram4_end // r1 - point to byte after the end of SRAM
|
||
|
bl memset_reg
|
||
|
|
||
|
ldr r0, =sram6_start // r0 - point to beginning of SRAM
|
||
|
ldr r1, =sram6_end // r1 - point to byte after the end of SRAM
|
||
|
bl memset_reg
|
||
|
|
||
|
ldr r0, =boot_args_start // r0 - point to beginning of boot args
|
||
|
ldr r1, =boot_args_end // r1 - point to byte after the end of boot args
|
||
|
bl memset_reg
|
||
|
|
||
|
ldr r0, =sram3_start // r0 - point to beginning of SRAM
|
||
|
ldr r1, =__fb_start // r1 - point to beginning of framebuffer
|
||
|
bl memset_reg
|
||
|
|
||
|
ldr r0, =__fb_end // r0 - point to end of framebuffer
|
||
|
ldr r1, =sram5_end // r1 - point to byte after the end of SRAM
|
||
|
bl memset_reg
|
||
|
|
||
|
// copy data in from flash
|
||
|
ldr r0, =data_vma // dst addr
|
||
|
ldr r1, =data_lma // src addr
|
||
|
ldr r2, =data_size // size in bytes
|
||
|
bl memcpy
|
||
|
|
||
|
// copy sensitive data in from flash
|
||
|
ldr r0, =sensitive_vma // dst addr
|
||
|
ldr r1, =sensitive_lma // src addr
|
||
|
ldr r2, =sensitive_size // size in bytes
|
||
|
bl memcpy
|
||
|
|
||
|
// setup the stack protector (see build script "-fstack-protector-all") with an unpredictable value
|
||
|
bl rng_get
|
||
|
ldr r1, = __stack_chk_guard
|
||
|
str r0, [r1]
|
||
|
|
||
|
// re-enable exceptions
|
||
|
// according to "ARM Cortex-M Programming Guide to Memory Barrier Instructions" Application Note 321, section 4.7:
|
||
|
// "If it is not necessary to ensure that a pended interrupt is recognized immediately before
|
||
|
// subsequent operations, it is not necessary to insert a memory barrier instruction."
|
||
|
cpsie f
|
||
|
|
||
|
// enter the application code
|
||
|
bl main
|
||
|
|
||
|
b shutdown_privileged
|
||
|
|
||
|
.end
|