/** @file flash.c
 * Module handling flash memory interface registers.
 *
 * The module provides functions to configure the flash and perform read and
 * writes
 */

//--includes--------------------------------------------------------------------

#include "flash.h"
#include "flash_regs.h"


//--local definitions-----------------------------------------------------------

//--local variables-------------------------------------------------------------

static volatile struct FLASH* regs = (struct FLASH*)FLASH_BASE_ADDRESS;


//--public functions------------------------------------------------------------

/**
 * Sets the correct latency to compensate the core's clock speed. Latency must
 * never be too low or the system will crash due to errors when accessing the
 * flash, hence the warning in the header
 */
void flash_configure(enum FlashPreset preset)
{
	//restore default configuration
	regs->ACR.word &= ~0x3f;
	regs->ACR.word |= 0x30;

	//apply new configuration
	switch (preset) {
		case FLASH_PRESET_LOW_CLOCK_SPEED:
			reg_set(regs->ACR, FLASH_ACR_HLFCYA); //half cycle for power saving
			break;
		case FLASH_PRESET_MEDIUM_CLOCK_SPEED:
			reg_reset(regs->ACR, FLASH_ACR_LATENCY);
			reg_write(regs->ACR, FLASH_ACR_LATENCY, 0x1);
			break;
		case FLASH_PRESET_HIGH_CLOCK_SPEED:
			reg_reset(regs->ACR, FLASH_ACR_LATENCY);
			reg_write(regs->ACR, FLASH_ACR_LATENCY, 0x2);
			break;
		default:
			break;
	}
}


//--local functions-------------------------------------------------------------