/*
 * Copyright 2010 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Ben Skeggs
 */

#include "drmP.h"
#include "nouveau_drv.h"
#include "nouveau_pm.h"

/*XXX: boards using limits 0x40 need fixing, the register layout
 *     is correct here, but, there's some other funny magic
 *     that modifies things, so it's not likely we'll set/read
 *     the correct timings yet..  working on it...
 */

struct nv50_pm_state {
	struct pll_lims pll;
	enum pll_types type;
	int N, M, P;
};

int
nv50_pm_clock_get(struct drm_device *dev, u32 id)
{
	struct pll_lims pll;
	int P, N, M, ret;
	u32 reg0, reg1;

	ret = get_pll_limits(dev, id, &pll);
	if (ret)
		return ret;

	if (pll.vco2.maxfreq) {
		reg0 = nv_rd32(dev, pll.reg + 0);
		reg1 = nv_rd32(dev, pll.reg + 4);
		P = (reg0 & 0x00070000) >> 16;
		N = (reg1 & 0x0000ff00) >> 8;
		M = (reg1 & 0x000000ff);

		return ((pll.refclk * N / M) >> P);
	}

	reg0 = nv_rd32(dev, pll.reg + 4);
	P = (reg0 & 0x003f0000) >> 16;
	N = (reg0 & 0x0000ff00) >> 8;
	M = (reg0 & 0x000000ff);
	return pll.refclk * N / M / P;
}

void *
nv50_pm_clock_pre(struct drm_device *dev, struct nouveau_pm_level *perflvl,
		  u32 id, int khz)
{
	struct nv50_pm_state *state;
	int dummy, ret;

	state = kzalloc(sizeof(*state), GFP_KERNEL);
	if (!state)
		return ERR_PTR(-ENOMEM);
	state->type = id;

	ret = get_pll_limits(dev, id, &state->pll);
	if (ret < 0) {
		kfree(state);
		return (ret == -ENOENT) ? NULL : ERR_PTR(ret);
	}

	ret = nv50_calc_pll(dev, &state->pll, khz, &state->N, &state->M,
			    &dummy, &dummy, &state->P);
	if (ret < 0) {
		kfree(state);
		return ERR_PTR(ret);
	}

	return state;
}

void
nv50_pm_clock_set(struct drm_device *dev, void *pre_state)
{
	struct nv50_pm_state *state = pre_state;
	u32 reg = state->pll.reg, tmp;
	int N = state->N;
	int M = state->M;
	int P = state->P;

	if (state->pll.vco2.maxfreq) {
		if (state->type == PLL_MEMORY) {
			nv_wr32(dev, 0x100210, 0);
			nv_wr32(dev, 0x1002dc, 1);
		}

		tmp  = nv_rd32(dev, reg + 0) & 0xfff8ffff;
		tmp |= 0x80000000 | (P << 16);
		nv_wr32(dev, reg + 0, tmp);
		nv_wr32(dev, reg + 4, (N << 8) | M);

		if (state->type == PLL_MEMORY) {
			nv_wr32(dev, 0x1002dc, 0);
			nv_wr32(dev, 0x100210, 0x80000000);
		}
	} else {
		nv_wr32(dev, reg + 4, (P << 16) | (N << 8) | M);
	}

	kfree(state);
}