/*
 *  This program is free software; you can redistribute it and/or modify it
 *  under the terms of the GNU General Public License version 2 as published
 *  by the Free Software Foundation.
 *
 *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
 */

#include <linux/io.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/clk.h>

#include <asm/time.h>
#include <asm/irq.h>
#include <asm/div64.h>

#include <lantiq_soc.h>

#include "../clk.h"

static unsigned int ram_clocks[] = {
	CLOCK_167M, CLOCK_133M, CLOCK_111M, CLOCK_83M };
#define DDR_HZ ram_clocks[ltq_cgu_r32(CGU_SYS) & 0x3]

/* legacy xway clock */
#define CGU_SYS			0x10

/* vr9 clock */
#define CGU_SYS_VR9		0x0c
#define CGU_IF_CLK_VR9		0x24

unsigned long ltq_danube_fpi_hz(void)
{
	unsigned long ddr_clock = DDR_HZ;

	if (ltq_cgu_r32(CGU_SYS) & 0x40)
		return ddr_clock >> 1;
	return ddr_clock;
}

unsigned long ltq_danube_cpu_hz(void)
{
	switch (ltq_cgu_r32(CGU_SYS) & 0xc) {
	case 0:
		return CLOCK_333M;
	case 4:
		return DDR_HZ;
	case 8:
		return DDR_HZ << 1;
	default:
		return DDR_HZ >> 1;
	}
}

unsigned long ltq_ar9_sys_hz(void)
{
	if (((ltq_cgu_r32(CGU_SYS) >> 3) & 0x3) == 0x2)
		return CLOCK_393M;
	return CLOCK_333M;
}

unsigned long ltq_ar9_fpi_hz(void)
{
	unsigned long sys = ltq_ar9_sys_hz();

	if (ltq_cgu_r32(CGU_SYS) & BIT(0))
		return sys;
	return sys >> 1;
}

unsigned long ltq_ar9_cpu_hz(void)
{
	if (ltq_cgu_r32(CGU_SYS) & BIT(2))
		return ltq_ar9_fpi_hz();
	else
		return ltq_ar9_sys_hz();
}

unsigned long ltq_vr9_cpu_hz(void)
{
	unsigned int cpu_sel;
	unsigned long clk;

	cpu_sel = (ltq_cgu_r32(CGU_SYS_VR9) >> 4) & 0xf;

	switch (cpu_sel) {
	case 0:
		clk = CLOCK_600M;
		break;
	case 1:
		clk = CLOCK_500M;
		break;
	case 2:
		clk = CLOCK_393M;
		break;
	case 3:
		clk = CLOCK_333M;
		break;
	case 5:
	case 6:
		clk = CLOCK_196_608M;
		break;
	case 7:
		clk = CLOCK_167M;
		break;
	case 4:
	case 8:
	case 9:
		clk = CLOCK_125M;
		break;
	default:
		clk = 0;
		break;
	}

	return clk;
}

unsigned long ltq_vr9_fpi_hz(void)
{
	unsigned int ocp_sel, cpu_clk;
	unsigned long clk;

	cpu_clk = ltq_vr9_cpu_hz();
	ocp_sel = ltq_cgu_r32(CGU_SYS_VR9) & 0x3;

	switch (ocp_sel) {
	case 0:
		/* OCP ratio 1 */
		clk = cpu_clk;
		break;
	case 2:
		/* OCP ratio 2 */
		clk = cpu_clk / 2;
		break;
	case 3:
		/* OCP ratio 2.5 */
		clk = (cpu_clk * 2) / 5;
		break;
	case 4:
		/* OCP ratio 3 */
		clk = cpu_clk / 3;
		break;
	default:
		clk = 0;
		break;
	}

	return clk;
}