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#define LOG_LEVEL 5
#include "lib.h"
struct PACKED payload {
uint64_t entry;
uint32_t size;
uint32_t cksum;
uint8_t data[];
};
extern const struct payload payload;
#define CLOCK 16000000
#define CKSUM 1
void kmain() {
{
TRACE("uart init\n");
uart_init(115200);
gpio_set_function(14, GPIO_UART);
gpio_set_function(15, GPIO_UART);
uartmux_configure(uartmux_signal_number(14), 0, UARTMUX_TX);
uartmux_configure(uartmux_signal_number(15), 0, UARTMUX_RX);
}
INFO("bootloader init\n");
{
TRACE("psram init\n");
psram_init();
TRACE("psram check\n");
volatile u32 *psram = (volatile u32 *)0x50000000;
put32(psram, 0xdeadbeef);
u32 x = get32(psram);
DEBUG("read back 0x%x from psram\n", x);
if (x != 0xdeadbeef) {
ERROR("psram init failed!\n");
while(1);
}
INFO("psram init success\n");
}
TRACE("timer init\n");
timer_init(CLOCK);
INFO("addr = 0x%lx\n", payload.entry);
INFO("size = 0x%x\n", payload.size);
INFO("cksum = 0x%x\n", payload.cksum);
DEBUG("copying %d bytes of code to address %p\n", payload.size, payload.entry);
u64 start = timer_read();
memcpy((void *)payload.entry, payload.data, payload.size);
u64 end = timer_read();
u64 ms = (end - start) * 1000 / CLOCK;
DEBUG("memcpy took %d ms\n", ms);
#if CKSUM
start = timer_read();
uint32_t cksum = crc32((void *)payload.entry, payload.size);
end = timer_read();
ms = (end - start) * 1000 / CLOCK;
DEBUG("crc32 took %d ms\n", ms);
if (payload.cksum != cksum) {
ERROR("invalid checksum: got 0x%x, expected 0x%x\n", cksum, payload.cksum);
ERROR("refusing to boot\n");
while(1);
} else {
INFO("valid checksum: 0x%x\n", cksum);
}
#else
#warning "Checksum verification disabled."
WARN("not verifying checksum\n");
#endif
TRACE("branching to code\n");
void (*fn)(void) = (void (*)(void))payload.entry;
fn();
WARN("code returned to bootloader\n");
}
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