S905D3 bootrom dump tool

S905D3_dump_bootrom.c

/*
 * S905D3_dump_bootrom.c - S905D3 bootrom dump tool
 * $ aarch64-linux-gnu-gcc -O3 -nostdlib -Wl,--build-id=none -o S905D3_dump_bootrom.elf S905D3_dump_bootrom.c
 * $ aarch64-linux-gnu-objcopy -O binary -j .text S905D3_dump_bootrom.elf S905D3_dump_bootrom.bin
 * 
 * derived from https://github.com/khadas/u-boot/blob/khadas-vims-pie/arch/arm/cpu/armv8/g12a/firmware/scp_task/uart.c
 *
 * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

#define P_WATCHDOG_RESET (volatile unsigned int *)0xFFD0F0DC
#define UART_PORT_CONS 0xFF803000
#define UART_STAT_MASK_TFIFO_FULL			(1<<21)
#define UART_STAT_MASK_TFIFO_EMPTY			(1<<22)
#define UART_WFIFO      (0<<2)
#define UART_STATUS     (3<<2)
#define P_UART(uart_base, reg)		(uart_base+reg)
#define P_UART_WFIFO(uart_base)		P_UART(uart_base, UART_WFIFO)
#define P_UART_MODE(uart_base)		P_UART(uart_base, UART_MODE)
#define P_UART_CTRL(uart_base)		P_UART(uart_base, UART_CTRL)
#define P_UART_STATUS(uart_base)	P_UART(uart_base, UART_STATUS)

#define writel(v, addr) (*((volatile unsigned *)(addr)) = v)
#define readl(addr) (*((volatile unsigned *)(addr)))

static inline int uart_tx_isfull(void)
{
	return readl(P_UART_STATUS(UART_PORT_CONS)) &
		UART_STAT_MASK_TFIFO_FULL;
}

static inline void uart_tx_flush(void)
{
	while (!(readl(P_UART_STATUS(UART_PORT_CONS)) &
		UART_STAT_MASK_TFIFO_EMPTY))
		;
}

static inline int uart_putc(int c)
{
	if (c == '\n')
		uart_putc('\r');

	/* Wait until TX is not full */
	while (uart_tx_isfull())
		;

	writel((char)c, P_UART_WFIFO(UART_PORT_CONS));
	/*wait_uart_empty();*/
	uart_tx_flush();
	return c;
}

static inline void uart_put_hex(unsigned int data, unsigned bitlen)
{
	int i;
	unsigned char s;
	for (i = bitlen - 4; i >= 0; i -= 4) {
		if ((data >> i) == 0) {
			uart_putc(0x30);
			continue;
		}
		s = (data >> i) & 0xf;
		if (s < 10)
			uart_putc(0x30 + s);
		else
			uart_putc(0x61 + s - 10);
	}
}

static inline void watchdog_reset(void)
{
	*P_WATCHDOG_RESET = 0;
}

void _start(){
    unsigned int bootrom_addr = 0xFFFF0000;
    while(bootrom_addr)
    {
        uart_put_hex(*(unsigned char *)(bootrom_addr++), 8);
        watchdog_reset();
    }
}