#include "system/LPC11xx.h"
#include "spi.h"
#include "uart.h"


void rom_select() {
	LPC_GPIO0->MASKED_ACCESS[1 << 11] = 0x0;
}


void rom_deselect() {
	LPC_GPIO0->MASKED_ACCESS[1 << 11] = 0x800;
}


int rom_init() {
	char bytes[3];
	rom_select();
	spi_send_recv(0x9F);
	
	bytes[0] = spi_send_recv(0xFF);
	bytes[1] = spi_send_recv(0xFF);
	bytes[2] = spi_send_recv(0xFF);

	rom_deselect();

	uart_printf("SPI ROM: %.2X %.2X %.2X\r\n", bytes[0], bytes[1], bytes[2]);

	return 0;
}


static void _wait_until_ready() {
	char b;
	
	for (;;) {
		rom_select();
		spi_send_recv(0x05);
		b = spi_send_recv(0xFF);
		rom_deselect();

		if (!(b & 1))
			break;
	}

}


void rom_erase() {
	rom_select();
	spi_send_recv(0x06);
	rom_deselect();
	
	rom_select();
	spi_send_recv(0xC7);
	rom_deselect();

	_wait_until_ready();
}


void rom_write_page(int page, char *data) {
	int i;

	rom_select();
	spi_send_recv(0x06);
	rom_deselect();

	rom_select();
	spi_send_recv(0x2);
	spi_send_recv((page >> 8) & 0xFF);
	spi_send_recv(page & 0xFF);
	spi_send_recv(0x0);

	for (i = 0; i < 256; i++)
		spi_send_recv(data[i]);
	
	rom_deselect();
	
	_wait_until_ready();

	rom_select();
	spi_send_recv(0x04);
	rom_deselect();
}


void rom_read_page(int page, char *data) {
	int i;

	rom_select();
	spi_send_recv(0x03);
	spi_send_recv(page >> 8);
	spi_send_recv(page);
	spi_send_recv(0x0);

	for (i = 0; i < 256; i++)
		data[i] = spi_send_recv(0xFF);
	rom_deselect();
}