Merge pull request #61 from mmicko/linker-script

Created lds file (section mapping) and init for data and bss sections
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Clifford Wolf 2018-08-14 13:05:56 +02:00 committed by GitHub
commit ce9d92939a
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3 changed files with 75 additions and 13 deletions

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@ -39,10 +39,10 @@ firmware.elf: sections.lds start.s firmware.c
riscv32-unknown-elf-gcc -march=rv32imc -Wl,-Bstatic,-T,sections.lds,--strip-debug -ffreestanding -nostdlib -o firmware.elf start.s firmware.c
firmware.hex: firmware.elf
riscv32-unknown-elf-objcopy -O verilog firmware.elf /dev/stdout | sed -e '1 s/@00000000/@00100000/; 2,65537 d;' > firmware.hex
riscv32-unknown-elf-objcopy -O verilog firmware.elf > firmware.hex
firmware.bin: firmware.elf
riscv32-unknown-elf-objcopy -O binary firmware.elf /dev/stdout | tail -c +1048577 > firmware.bin
riscv32-unknown-elf-objcopy -O binary firmware.elf > firmware.bin
# ---- Testbench for SPI Flash Model ----

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@ -340,8 +340,19 @@ void cmd_benchmark_all()
// --------------------------------------------------------
extern uint32_t _sidata, _sdata, _edata, _sbss, _ebss;
void main()
{
// copy data section
for (uint32_t *src = &_sidata, *dest = &_sdata; dest < &_edata;) {
*dest++ = *src++;
}
// zero out .bss section
for (uint32_t *dest = &_sbss; dest < &_ebss;) {
*dest++ = 0;
}
reg_uart_clkdiv = 104;
set_flash_qspi_flag();

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@ -1,11 +1,62 @@
MEMORY
{
FLASH (rx) : ORIGIN = 0x00100000, LENGTH = 0x400000 /* entire flash, 4 MiB */
RAM (xrw) : ORIGIN = 0x00000000, LENGTH = 0x000400 /* 1 KB */
}
SECTIONS {
.memory : {
sram = 0;
*(.data);
*(.bss);
. = 0x100000;
start*(.text);
*(.text);
*(*);
}
/* The program code and other data goes into FLASH */
.text :
{
. = ALIGN(4);
*(.text) /* .text sections (code) */
*(.text*) /* .text* sections (code) */
*(.rodata) /* .rodata sections (constants, strings, etc.) */
*(.rodata*) /* .rodata* sections (constants, strings, etc.) */
*(.srodata) /* .rodata sections (constants, strings, etc.) */
*(.srodata*) /* .rodata* sections (constants, strings, etc.) */
_etext = .; /* define a global symbol at end of code */
_sidata = _etext; /* This is used by the startup in order to initialize the .data secion */
} >FLASH
/* This is the initialized data section
The program executes knowing that the data is in the RAM
but the loader puts the initial values in the FLASH (inidata).
It is one task of the startup to copy the initial values from FLASH to RAM. */
.data : AT ( _sidata )
{
. = ALIGN(4);
_sdata = .; /* create a global symbol at data start; used by startup code in order to initialise the .data section in RAM */
_ram_start = .; /* create a global symbol at ram start for garbage collector */
. = ALIGN(4);
*(.data) /* .data sections */
*(.data*) /* .data* sections */
*(.sdata) /* .sdata sections */
*(.sdata*) /* .sdata* sections */
. = ALIGN(4);
_edata = .; /* define a global symbol at data end; used by startup code in order to initialise the .data section in RAM */
} >RAM
/* Uninitialized data section */
.bss :
{
. = ALIGN(4);
_sbss = .; /* define a global symbol at bss start; used by startup code */
*(.bss)
*(.bss*)
*(.sbss)
*(.sbss*)
*(COMMON)
. = ALIGN(4);
_ebss = .; /* define a global symbol at bss end; used by startup code */
} >RAM
/* this is to define the start of the heap, and make sure we have a minimum size */
.heap :
{
. = ALIGN(4);
_heap_start = .; /* define a global symbol at heap start */
} >RAM
}