mirror of
https://github.com/trezor/trezor-firmware.git
synced 2024-11-30 11:28:21 +00:00
108 lines
2.7 KiB
ArmAsm
108 lines
2.7 KiB
ArmAsm
.syntax unified
|
|
|
|
.text
|
|
|
|
.global memset_reg
|
|
.type memset_reg, STT_FUNC
|
|
memset_reg:
|
|
// call with the following (note that the arguments are not validated prior to use):
|
|
// r0 - address of first word to write (inclusive)
|
|
// r1 - address of first word following the address in r0 to NOT write (exclusive)
|
|
// r2 - word value to be written
|
|
// both addresses in r0 and r1 needs to be divisible by 4!
|
|
.L_loop_begin:
|
|
str r2, [r0], 4 // store the word in r2 to the address in r0, post-indexed
|
|
cmp r0, r1
|
|
bne .L_loop_begin
|
|
bx lr
|
|
|
|
.global reset_handler
|
|
.type reset_handler, STT_FUNC
|
|
reset_handler:
|
|
|
|
// We need to perform VTOR setup case an old bootloader (<1.8.0)
|
|
// is starting the new firmware, these will be set incorrectly.
|
|
|
|
// To make development easier, set only if we are in privileged
|
|
// mode. This resolves annoying combinations of PRODUCTION
|
|
// settings for bootloader and FW.
|
|
// Normally only signed firmware will let bootloader start FW
|
|
// in privileged mode (PRODUCTION=1 variants with signed everything).
|
|
// But with devel bootloader we let FW start in privileged mode
|
|
// and let's do the check if we can set VTOR without fault
|
|
|
|
// These two instructions are just for debug testing how unprivileged
|
|
// FW is handled
|
|
//mov r0, 1
|
|
//msr control, r0 // set unprivileged
|
|
|
|
ldr sp, =_stack // setup stack
|
|
|
|
// are we privileged? if so, fix VTOR, otherwise skip
|
|
mrs r3, control
|
|
and r3, r3, #1
|
|
cmp r3, #1
|
|
beq .setup_as_unprivileged
|
|
|
|
ldr r0, =0xE000ED08 // r0 = VTOR address
|
|
ldr r1, =0x08010400 // r1 = FLASH_APP_START
|
|
str r1, [r0] // assign
|
|
dsb
|
|
isb
|
|
|
|
.setup_as_unprivileged:
|
|
ldr r0, =_ram_start // r0 - point to beginning of SRAM
|
|
ldr r1, =_ram_end // r1 - point to byte after the end of SRAM
|
|
ldr r2, =0 // r2 - the byte-sized value to be written
|
|
bl memset_reg
|
|
|
|
// copy .data section from flash to SRAM
|
|
ldr r0, =_data // dst addr
|
|
ldr r1, =_data_loadaddr // src addr
|
|
ldr r2, =_data_size // length in bytes
|
|
bl memcpy
|
|
|
|
// enter the application code
|
|
bl main
|
|
|
|
// shutdown if the application code returns
|
|
b shutdown
|
|
|
|
.global shutdown
|
|
.type shutdown, STT_FUNC
|
|
shutdown:
|
|
cpsid f
|
|
ldr r0, =0
|
|
mov r1, r0
|
|
mov r2, r0
|
|
mov r3, r0
|
|
mov r4, r0
|
|
mov r5, r0
|
|
mov r6, r0
|
|
mov r7, r0
|
|
mov r8, r0
|
|
mov r9, r0
|
|
mov r10, r0
|
|
mov r11, r0
|
|
mov r12, r0
|
|
ldr lr, =0xffffffff
|
|
ldr r0, =_ram_start
|
|
ldr r1, =_ram_end
|
|
// set to value in r2
|
|
bl memset_reg
|
|
b . // loop forever
|
|
|
|
.ltorg // dump literal pool (for the ldr ...,=... commands above)
|
|
|
|
.global sv_call_handler
|
|
.type sv_call_handler, STT_FUNC
|
|
|
|
sv_call_handler:
|
|
tst lr, #4
|
|
ite eq
|
|
mrseq r0, msp
|
|
mrsne r0, psp
|
|
b svc_handler_main
|
|
|
|
.end
|