Files
picovga-RGsB/_sdk/bootrom.c
2021-06-10 19:07:49 +02:00

39 lines
1.2 KiB
C

/*
* Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include "pico/bootrom.h"
/// \tag::table_lookup[]
// Bootrom function: rom_table_lookup
// Returns the 32 bit pointer into the ROM if found or NULL otherwise.
typedef void *(*rom_table_lookup_fn)(uint16_t *table, uint32_t code);
// Convert a 16 bit pointer stored at the given rom address into a 32 bit pointer
#define rom_hword_as_ptr(rom_address) (void *)(uintptr_t)(*(uint16_t *)rom_address)
void *rom_func_lookup(uint32_t code) {
rom_table_lookup_fn rom_table_lookup = (rom_table_lookup_fn) rom_hword_as_ptr(0x18);
uint16_t *func_table = (uint16_t *) rom_hword_as_ptr(0x14);
return rom_table_lookup(func_table, code);
}
void *rom_data_lookup(uint32_t code) {
rom_table_lookup_fn rom_table_lookup = (rom_table_lookup_fn) rom_hword_as_ptr(0x18);
uint16_t *data_table = (uint16_t *) rom_hword_as_ptr(0x16);
return rom_table_lookup(data_table, code);
}
/// \end::table_lookup[]
bool rom_funcs_lookup(uint32_t *table, unsigned int count) {
bool ok = true;
for (unsigned int i = 0; i < count; i++) {
table[i] = (uintptr_t) rom_func_lookup(table[i]);
if (!table[i]) ok = false;
}
return ok;
}