feat(legacy): make debugging less painful, remove PRODUCTION macro matrix, split reset_handlers

legacy/Makefile

@@ -1,6 +1,5 @@
 ifneq ($(EMULATOR),1)
 OBJS += setup.o
-OBJS += startup.o
 OBJS += timer.o
 endif
 

legacy/bootloader/Makefile

@@ -1,5 +1,6 @@
 NAME  = bootloader-unaligned
 
+OBJS += startup.o
 OBJS += bootloader.o
 OBJS += usb.o
 
@@ -18,7 +19,6 @@ OBJS += ../oled.small.o
 OBJS += ../random_delays.small.o
 OBJS += ../rng.small.o
 OBJS += ../setup.small.o
-OBJS += ../startup.o
 OBJS += ../supervise.small.o
 OBJS += ../timer.small.o
 OBJS += ../usb21_standard.small.o

legacy/bootloader/startup.S

@@ -0,0 +1,79 @@
+  .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:
+
+  ldr r0, =_stay_in_bootloader_flag_addr  // r0 - address of storage for "stay in bootloader" flag
+  ldr r11, [r0]        // r11 - keep in register and hope it gets to main
+
+  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

legacy/firmware/Makefile

@@ -40,6 +40,7 @@ OBJS += usb.o
 OBJS += bl_check.o
 OBJS += otp.o
 OBJS += header.o
+OBJS += startup.o
 endif
 
 OBJS += messages.o

legacy/firmware/startup.S

@@ -20,7 +20,7 @@ memset_reg:
   .type reset_handler, STT_FUNC
 reset_handler:
 
-// We need to perform VTOR+stack setup case an old bootloader (<1.8.0)
+// 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
@@ -31,14 +31,14 @@ reset_handler:
 // But with devel bootloader we let FW start in privileged mode
 // and let's do the check if we can set VTOR without fault
 
-// Since this startup code is shared with bootloader and FW,
-// a) in case of bootloader MCU starts in privileged mode,
-//    so the jump to "setup_as_unprivileged" never happens.
-//    VTOR and stack are set from MCU startup
-// b) in case of FW it will attempt to set VTOR and stack
-//    which will work for both signed bootloader+FW, but
-//    also for other variants with debug bootloader and
-//    unsigned FW or official bootloader and usigned FW
+  // 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
@@ -47,15 +47,10 @@ reset_handler:
   ldr r0, =0xE000ED08  // r0 = VTOR address
   ldr r1, =0x08010400  // r1 = FLASH_APP_START
   str r1, [r0]         // assign
-  ldr r0, =_stack      // r0 = stack pointer
-  msr msp, r0          // set stack pointer
   dsb
   isb
 
   .setup_as_unprivileged:
-  ldr r0, =_stay_in_bootloader_flag_addr  // r0 - address of storage for "stay in bootloader" flag
-  ldr r11, [r0]        // r11 - keep in register and hope it gets to main
-
   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

legacy/intermediate_fw/Makefile

@@ -5,6 +5,7 @@ NAME  = trezor
 OBJS += trezor.o
 OBJS += header.o
 OBJS += bl_check.o
+OBJS += startup.o
 OBJS += ../vendor/trezor-crypto/memzero.o
 OBJS += ../vendor/trezor-crypto/sha2.o
 

legacy/intermediate_fw/startup.S

@@ -0,0 +1 @@
+../firmware/startup.S