src/rp2_common/pico_crt0/embedded_start_block.inc.S

#if !defined(PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM)
// todo decide whether we want this item for RP2040 by default, probably not (there are a zilloon binaries out there without it)
#if !PICO_RP2040
#define PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM 1
#endif
#endif

#ifndef PICO_CRT0_INCLUDE_PICOBIN_BLOCK
#define PICO_CRT0_INCLUDE_PICOBIN_BLOCK PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM
#endif

#ifndef PICO_CRT0_INCLUDE_PICOBIN_END_BLOCK
#define PICO_CRT0_INCLUDE_PICOBIN_END_BLOCK (PICO_CRT0_INCLUDE_PICOBIN_BLOCK && !PICO_NO_FLASH)
#endif

#if PICO_CRT0_IMAGE_TYPE_TBYB
#define CRT0_TBYB_FLAG PICOBIN_IMAGE_TYPE_EXE_TBYB_BITS
#else
#define CRT0_TBYB_FLAG 0
#endif

#if defined(PICO_CRT0_VERSION_MINOR) && !defined(PICO_CRT0_VERSION_MAJOR)
#define PICO_CRT0_VERSION_MAJOR 0
#endif

#if PICO_CRT0_INCLUDE_PICOBIN_BLOCK
.section .embedded_block, "a"
.p2align 2
embedded_block:
.word PICOBIN_BLOCK_MARKER_START

#if PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM
// include an IMAGE_TYPE item at the start so this block is a valid IMAGE_DEF block, and can be used as a basis
// for booting the binary with a known type.
.byte PICOBIN_BLOCK_ITEM_1BS_IMAGE_TYPE
.byte 0x1 // 1 word
#ifdef PICO_CRT0_IMAGE_TYPE_ITEM_VALUE
.hword PICO_CRT0_IMAGE_TYPE_ITEM_VALUE
#elif defined(__riscv)
.hword PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
       PICOBIN_IMAGE_TYPE_EXE_CPU_AS_BITS(RISCV) | \
       PICOBIN_IMAGE_TYPE_EXE_CHIP_AS_BITS(RP2350) | \
       CRT0_TBYB_FLAG
#elif defined(PICO_RP2040)
.hword PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
       PICOBIN_IMAGE_TYPE_EXE_SECURITY_AS_BITS(NS) | \
       PICOBIN_IMAGE_TYPE_EXE_CPU_AS_BITS(ARM) | \
       PICOBIN_IMAGE_TYPE_EXE_CHIP_AS_BITS(RP2040) | \
       CRT0_TBYB_FLAG
#else
.hword PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
       PICOBIN_IMAGE_TYPE_EXE_SECURITY_AS_BITS(S) | \
       PICOBIN_IMAGE_TYPE_EXE_CPU_AS_BITS(ARM) | \
       PICOBIN_IMAGE_TYPE_EXE_CHIP_AS_BITS(RP2350) | \
       CRT0_TBYB_FLAG
#endif
#else
// if no image type, then add ignored item
.byte PICOBIN_BLOCK_ITEM_2BS_IGNORED
.byte 0x1 // 1 word
.hword 0
#endif

#ifdef PICO_CRT0_VERSION_MAJOR
.byte PICOBIN_BLOCK_ITEM_1BS_VERSION
.byte 0x2 // 2 words
.hword 0
#ifdef PICO_CRT0_VERSION_MINOR
.hword PICO_CRT0_VERSION_MINOR
#else
.hword 0
#endif
.hword PICO_CRT0_VERSION_MAJOR
#endif

#ifdef __riscv
// On RISC-V the default entry point from bootrom is the start of the binary, but
// we have our vtable at the start, so we must include an entry point
.byte PICOBIN_BLOCK_ITEM_1BS_ENTRY_POINT
.byte 0x3 // word size to next item
.byte 0 // pad
.byte 0 // pad
.word _reset_handler
.word SRAM_END // stack pointer
#endif

#ifndef PICO_RP2040
#if PICO_NO_FLASH
// If no_flash bin, then include a vector table item
.byte PICOBIN_BLOCK_ITEM_1BS_VECTOR_TABLE
.byte 0x2
.hword 0
.word __vectors
#endif
#endif

.byte PICOBIN_BLOCK_ITEM_2BS_LAST
.hword (embedded_block_end - embedded_block - 16 ) / 4 // total size of all
.byte 0
#if PICO_CRT0_INCLUDE_PICOBIN_END_BLOCK
.word embedded_end_block - embedded_block
#else
// offset from this block to next block in loop (since we are a single block loop, we point back to ourselves
// so the offset is 0)
.word 0
#endif
.word PICOBIN_BLOCK_MARKER_END
embedded_block_end:
#endif