From 9300a510c55cca4e9706bd13b7e3b9f37d658ce0 Mon Sep 17 00:00:00 2001 From: Miodrag Milanovic Date: Mon, 16 Apr 2018 20:04:01 +0200 Subject: [PATCH] Created lfs file (section mappint) and init for data and bss sections --- picosoc/Makefile | 4 +-- picosoc/firmware.c | 13 +++++++- picosoc/sections.lds | 71 +++++++++++++++++++++++++++++++++++++------- 3 files changed, 75 insertions(+), 13 deletions(-) diff --git a/picosoc/Makefile b/picosoc/Makefile index 88d3014..3eacbcc 100644 --- a/picosoc/Makefile +++ b/picosoc/Makefile @@ -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 ---- diff --git a/picosoc/firmware.c b/picosoc/firmware.c index 5c0bec1..7e60932 100644 --- a/picosoc/firmware.c +++ b/picosoc/firmware.c @@ -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(); diff --git a/picosoc/sections.lds b/picosoc/sections.lds index 3e38ca9..6c83665 100644 --- a/picosoc/sections.lds +++ b/picosoc/sections.lds @@ -1,11 +1,62 @@ -SECTIONS { - .memory : { - sram = 0; - *(.data); - *(.bss); - . = 0x100000; - start*(.text); - *(.text); - *(*); - } +MEMORY +{ + FLASH (rx) : ORIGIN = 0x00100000, LENGTH = 0x400000 /* entire flash, 4 MiB */ + RAM (xrw) : ORIGIN = 0x00000000, LENGTH = 0x000400 /* 1 KB */ +} + +SECTIONS { + /* 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 }