blackmagic/flashstub/stm32l05x-nvm-prog-write.cc

113 lines
3.5 KiB
C++

/* @file stm32l05x-nvm-prog-write.cc
*
* This file is part of the Black Magic Debug project.
*
* Copyright (C) 2014 Woollysoft
* Written by Marc Singer <elf@woollysoft.com>
*
* This program 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.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
/* -----------
DESCRIPTION
-----------
NVM program flash writing stub for STM32L05x, a Cortex-M0+ core.
The stub uses SRAM to host the code fragment and source data to
perform a write to flash.
This stub works with the STM32L1xx given a few options.
If you plan to modify this routine and emit a new stub, make sure
to audit the code. We don't have a stack so we cannot make calls
that save the link pointer. IOW, the inline functions should be be
inlined.
*/
#include <stdint.h>
#include <string.h>
#include "../src/include/stm32lx-nvm.h"
/* Write a block of bytes to flash. The called is responsible for
making sure that the address are aligned and that the count is an
even multiple of words. */
extern "C" void __attribute((naked)) stm32l05x_nvm_prog_write () {
// Leave room for INFO at second word of routine
__asm volatile ("b 0f\n\t"
".align 2\n\t"
".word 0\n\t"
".word 0\n\t"
".word 0\n\t"
".word 0\n\t"
".word 0\n\t"
"0:");
auto& nvm = Nvm (Info.nvm);
if (!unlock (nvm))
goto quit;
nvm.sr = STM32Lx_NVM_SR_ERR_M; // Clear errors
while (Info.size > 0) {
// Either we're not half-page aligned or we have less than a half
// page to write
if (Info.size < Info.page_size/2
|| (reinterpret_cast<uint32_t> (Info.destination)
& (Info.page_size/2 - 1))) {
nvm.pecr = (Info.options & OPT_STM32L1) ? 0
: STM32Lx_NVM_PECR_PROG; // Word programming
size_t c = Info.page_size/2
- (reinterpret_cast<uint32_t> (Info.destination)
& (Info.page_size/2 - 1));
if (c > Info.size)
c = Info.size;
Info.size -= c;
c /= 4;
while (c--) {
uint32_t v = *Info.source++;
*Info.destination++ = v;
if (nvm.sr & STM32Lx_NVM_SR_ERR_M)
goto quit;
}
}
// Or we are writing a half-page(s)
else {
nvm.pecr = STM32Lx_NVM_PECR_PROG | STM32Lx_NVM_PECR_FPRG; // Half-page prg
size_t c = Info.size & ~(Info.page_size/2 - 1);
Info.size -= c;
c /= 4;
while (c--) {
uint32_t v = *Info.source++;
*Info.destination++ = v;
}
if (nvm.sr & STM32Lx_NVM_SR_ERR_M)
goto quit;
}
}
quit:
lock (nvm);
__asm volatile ("bkpt");
}
/*
Local Variables:
compile-command: "/opt/arm/arm-none-eabi-g++ -mcpu=cortex-m0plus -g -c -std=c++11 -mthumb -o stm32l05x-nvm-prog-write.o -Os -Wa,-ahndl=stm32l05x-nvm-prog-write.lst stm32l05x-nvm-prog-write.cc ; /opt/arm/arm-none-eabi-objdump -S stm32l05x-nvm-prog-write.o | ./code-to-array.pl > stm32l05x-nvm-prog-write.stub"
End:
*/