[deliverable/linux.git] / drivers / gpu / drm / nouveau / core / subdev / clock / pllnv04.c

/*
 * Copyright 1993-2003 NVIDIA, Corporation
 * Copyright 2007-2009 Stuart Bennett
 *
 * 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 AUTHORS 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.
 */

#include <subdev/bios.h>
#include <subdev/bios/pll.h>

#include "pll.h"

static int
getMNP_single(struct nouveau_subdev *subdev, struct nvbios_pll *info, int clk,
	      int *pN, int *pM, int *pP)
{
	/* Find M, N and P for a single stage PLL
	 *
	 * Note that some bioses (NV3x) have lookup tables of precomputed MNP
	 * values, but we're too lazy to use those atm
	 *
	 * "clk" parameter in kHz
	 * returns calculated clock
	 */
	int cv = nouveau_bios(subdev)->version.chip;
	int minvco = info->vco1.min_freq, maxvco = info->vco1.max_freq;
	int minM = info->vco1.min_m, maxM = info->vco1.max_m;
	int minN = info->vco1.min_n, maxN = info->vco1.max_n;
	int minU = info->vco1.min_inputfreq;
	int maxU = info->vco1.max_inputfreq;
	int minP = info->min_p;
	int maxP = info->max_p_usable;
	int crystal = info->refclk;
	int M, N, thisP, P;
	int clkP, calcclk;
	int delta, bestdelta = INT_MAX;
	int bestclk = 0;

	/* this division verified for nv20, nv18, nv28 (Haiku), and nv34 */
	/* possibly correlated with introduction of 27MHz crystal */
	if (cv < 0x17 || cv == 0x1a || cv == 0x20) {
		if (clk > 250000)
			maxM = 6;
		if (clk > 340000)
			maxM = 2;
	} else if (cv < 0x40) {
		if (clk > 150000)
			maxM = 6;
		if (clk > 200000)
			maxM = 4;
		if (clk > 340000)
			maxM = 2;
	}

	P = 1 << maxP;
	if ((clk * P) < minvco) {
		minvco = clk * maxP;
		maxvco = minvco * 2;
	}

	if (clk + clk/200 > maxvco)	/* +0.5% */
		maxvco = clk + clk/200;

	/* NV34 goes maxlog2P->0, NV20 goes 0->maxlog2P */
	for (thisP = minP; thisP <= maxP; thisP++) {
		P = 1 << thisP;
		clkP = clk * P;

		if (clkP < minvco)
			continue;
		if (clkP > maxvco)
			return bestclk;

		for (M = minM; M <= maxM; M++) {
			if (crystal/M < minU)
				return bestclk;
			if (crystal/M > maxU)
				continue;

			/* add crystal/2 to round better */
			N = (clkP * M + crystal/2) / crystal;

			if (N < minN)
				continue;
			if (N > maxN)
				break;

			/* more rounding additions */
			calcclk = ((N * crystal + P/2) / P + M/2) / M;
			delta = abs(calcclk - clk);
			/* we do an exhaustive search rather than terminating
			 * on an optimality condition...
			 */
			if (delta < bestdelta) {
				bestdelta = delta;
				bestclk = calcclk;
				*pN = N;
				*pM = M;
				*pP = thisP;
				if (delta == 0)	/* except this one */
					return bestclk;
			}
		}
	}

	return bestclk;
}

static int
getMNP_double(struct nouveau_subdev *subdev, struct nvbios_pll *info, int clk,
	      int *pN1, int *pM1, int *pN2, int *pM2, int *pP)
{
	/* Find M, N and P for a two stage PLL
	 *
	 * Note that some bioses (NV30+) have lookup tables of precomputed MNP
	 * values, but we're too lazy to use those atm
	 *
	 * "clk" parameter in kHz
	 * returns calculated clock
	 */
	int chip_version = nouveau_bios(subdev)->version.chip;
	int minvco1 = info->vco1.min_freq, maxvco1 = info->vco1.max_freq;
	int minvco2 = info->vco2.min_freq, maxvco2 = info->vco2.max_freq;
	int minU1 = info->vco1.min_inputfreq, minU2 = info->vco2.min_inputfreq;
	int maxU1 = info->vco1.max_inputfreq, maxU2 = info->vco2.max_inputfreq;
	int minM1 = info->vco1.min_m, maxM1 = info->vco1.max_m;
	int minN1 = info->vco1.min_n, maxN1 = info->vco1.max_n;
	int minM2 = info->vco2.min_m, maxM2 = info->vco2.max_m;
	int minN2 = info->vco2.min_n, maxN2 = info->vco2.max_n;
	int maxlog2P = info->max_p_usable;
	int crystal = info->refclk;
	bool fixedgain2 = (minM2 == maxM2 && minN2 == maxN2);
	int M1, N1, M2, N2, log2P;
	int clkP, calcclk1, calcclk2, calcclkout;
	int delta, bestdelta = INT_MAX;
	int bestclk = 0;

	int vco2 = (maxvco2 - maxvco2/200) / 2;
	for (log2P = 0; clk && log2P < maxlog2P && clk <= (vco2 >> log2P); log2P++)
		;
	clkP = clk << log2P;

	if (maxvco2 < clk + clk/200)	/* +0.5% */
		maxvco2 = clk + clk/200;

	for (M1 = minM1; M1 <= maxM1; M1++) {
		if (crystal/M1 < minU1)
			return bestclk;
		if (crystal/M1 > maxU1)
			continue;

		for (N1 = minN1; N1 <= maxN1; N1++) {
			calcclk1 = crystal * N1 / M1;
			if (calcclk1 < minvco1)
				continue;
			if (calcclk1 > maxvco1)
				break;

			for (M2 = minM2; M2 <= maxM2; M2++) {
				if (calcclk1/M2 < minU2)
					break;
				if (calcclk1/M2 > maxU2)
					continue;

				/* add calcclk1/2 to round better */
				N2 = (clkP * M2 + calcclk1/2) / calcclk1;
				if (N2 < minN2)
					continue;
				if (N2 > maxN2)
					break;

				if (!fixedgain2) {
					if (chip_version < 0x60)
						if (N2/M2 < 4 || N2/M2 > 10)
							continue;

					calcclk2 = calcclk1 * N2 / M2;
					if (calcclk2 < minvco2)
						break;
					if (calcclk2 > maxvco2)
						continue;
				} else
					calcclk2 = calcclk1;

				calcclkout = calcclk2 >> log2P;
				delta = abs(calcclkout - clk);
				/* we do an exhaustive search rather than terminating
				 * on an optimality condition...
				 */
				if (delta < bestdelta) {
					bestdelta = delta;
					bestclk = calcclkout;
					*pN1 = N1;
					*pM1 = M1;
					*pN2 = N2;
					*pM2 = M2;
					*pP = log2P;
					if (delta == 0)	/* except this one */
						return bestclk;
				}
			}
		}
	}

	return bestclk;
}

int
nv04_pll_calc(struct nouveau_subdev *subdev, struct nvbios_pll *info, u32 freq,
	      int *N1, int *M1, int *N2, int *M2, int *P)
{
	int ret;

	if (!info->vco2.max_freq) {
		ret = getMNP_single(subdev, info, freq, N1, M1, P);
		*N2 = 1;
		*M2 = 1;
	} else {
		ret = getMNP_double(subdev, info, freq, N1, M1, N2, M2, P);
	}

	if (!ret)
		nv_error(subdev, "unable to compute acceptable pll values\n");
	return ret;
}
Commit	Line	Data
70790f4f BS	1	/*
	2	* Copyright 1993-2003 NVIDIA, Corporation
	3	* Copyright 2007-2009 Stuart Bennett
	4	*
	5	* Permission is hereby granted, free of charge, to any person obtaining a
	6	* copy of this software and associated documentation files (the "Software"),
	7	* to deal in the Software without restriction, including without limitation
	8	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	9	* and/or sell copies of the Software, and to permit persons to whom the
	10	* Software is furnished to do so, subject to the following conditions:
	11	*
	12	* The above copyright notice and this permission notice shall be included in
	13	* all copies or substantial portions of the Software.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	18	* THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
	19	* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
	20	* OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	21	* SOFTWARE.
	22	*/
	23
70790f4f BS	24	#include <subdev/bios.h>
	25	#include <subdev/bios/pll.h>
	26
	27	#include "pll.h"
	28
	29	static int
7ada785f	30	getMNP_single(struct nouveau_subdev subdev, struct nvbios_pll info, int clk,
70790f4f BS	31	int pN, int pM, int *pP)
	32	{
	33	/* Find M, N and P for a single stage PLL
	34	*
	35	* Note that some bioses (NV3x) have lookup tables of precomputed MNP
	36	* values, but we're too lazy to use those atm
	37	*
	38	* "clk" parameter in kHz
	39	* returns calculated clock
	40	*/
7ada785f	41	int cv = nouveau_bios(subdev)->version.chip;
70790f4f BS	42	int minvco = info->vco1.min_freq, maxvco = info->vco1.max_freq;
	43	int minM = info->vco1.min_m, maxM = info->vco1.max_m;
	44	int minN = info->vco1.min_n, maxN = info->vco1.max_n;
	45	int minU = info->vco1.min_inputfreq;
	46	int maxU = info->vco1.max_inputfreq;
	47	int minP = info->min_p;
	48	int maxP = info->max_p_usable;
	49	int crystal = info->refclk;
	50	int M, N, thisP, P;
	51	int clkP, calcclk;
	52	int delta, bestdelta = INT_MAX;
	53	int bestclk = 0;
	54
	55	/* this division verified for nv20, nv18, nv28 (Haiku), and nv34 */
	56	/* possibly correlated with introduction of 27MHz crystal */
	57	if (cv < 0x17 \|\| cv == 0x1a \|\| cv == 0x20) {
	58	if (clk > 250000)
	59	maxM = 6;
	60	if (clk > 340000)
	61	maxM = 2;
	62	} else if (cv < 0x40) {
	63	if (clk > 150000)
	64	maxM = 6;
	65	if (clk > 200000)
	66	maxM = 4;
	67	if (clk > 340000)
	68	maxM = 2;
	69	}
	70
	71	P = 1 << maxP;
	72	if ((clk * P) < minvco) {
	73	minvco = clk * maxP;
	74	maxvco = minvco * 2;
	75	}
	76
	77	if (clk + clk/200 > maxvco) /* +0.5% */
	78	maxvco = clk + clk/200;
	79
	80	/* NV34 goes maxlog2P->0, NV20 goes 0->maxlog2P */
	81	for (thisP = minP; thisP <= maxP; thisP++) {
	82	P = 1 << thisP;
	83	clkP = clk * P;
	84
	85	if (clkP < minvco)
	86	continue;
	87	if (clkP > maxvco)
	88	return bestclk;
	89
	90	for (M = minM; M <= maxM; M++) {
	91	if (crystal/M < minU)
	92	return bestclk;
	93	if (crystal/M > maxU)
	94	continue;
	95
	96	/* add crystal/2 to round better */
	97	N = (clkP * M + crystal/2) / crystal;
	98
	99	if (N < minN)
	100	continue;
	101	if (N > maxN)
	102	break;
	103
	104	/* more rounding additions */
	105	calcclk = ((N * crystal + P/2) / P + M/2) / M;
106	delta = abs(calcclk - clk);
107	/* we do an exhaustive search rather than terminating
108	* on an optimality condition...
109	*/
110	if (delta < bestdelta) {
111	bestdelta = delta;
112	bestclk = calcclk;
113	*pN = N;
114	*pM = M;
115	*pP = thisP;
116	if (delta == 0) /* except this one */
117	return bestclk;
118	}
119	}
120	}
121
122	return bestclk;
123	}
124
125	static int
7ada785f	126	getMNP_double(struct nouveau_subdev subdev, struct nvbios_pll info, int clk,
70790f4f BS	127	int pN1, int pM1, int pN2, int pM2, int *pP)
	128	{
	129	/* Find M, N and P for a two stage PLL
	130	*
	131	* Note that some bioses (NV30+) have lookup tables of precomputed MNP
	132	* values, but we're too lazy to use those atm
	133	*
	134	* "clk" parameter in kHz
	135	* returns calculated clock
	136	*/
7ada785f	137	int chip_version = nouveau_bios(subdev)->version.chip;
70790f4f BS	138	int minvco1 = info->vco1.min_freq, maxvco1 = info->vco1.max_freq;
	139	int minvco2 = info->vco2.min_freq, maxvco2 = info->vco2.max_freq;
	140	int minU1 = info->vco1.min_inputfreq, minU2 = info->vco2.min_inputfreq;
	141	int maxU1 = info->vco1.max_inputfreq, maxU2 = info->vco2.max_inputfreq;
	142	int minM1 = info->vco1.min_m, maxM1 = info->vco1.max_m;
	143	int minN1 = info->vco1.min_n, maxN1 = info->vco1.max_n;
	144	int minM2 = info->vco2.min_m, maxM2 = info->vco2.max_m;
	145	int minN2 = info->vco2.min_n, maxN2 = info->vco2.max_n;
	146	int maxlog2P = info->max_p_usable;
	147	int crystal = info->refclk;
	148	bool fixedgain2 = (minM2 == maxM2 && minN2 == maxN2);
	149	int M1, N1, M2, N2, log2P;
	150	int clkP, calcclk1, calcclk2, calcclkout;
	151	int delta, bestdelta = INT_MAX;
	152	int bestclk = 0;
	153
	154	int vco2 = (maxvco2 - maxvco2/200) / 2;
	155	for (log2P = 0; clk && log2P < maxlog2P && clk <= (vco2 >> log2P); log2P++)
	156	;
	157	clkP = clk << log2P;
	158
	159	if (maxvco2 < clk + clk/200) /* +0.5% */
	160	maxvco2 = clk + clk/200;
	161
	162	for (M1 = minM1; M1 <= maxM1; M1++) {
	163	if (crystal/M1 < minU1)
	164	return bestclk;
	165	if (crystal/M1 > maxU1)
	166	continue;
	167
	168	for (N1 = minN1; N1 <= maxN1; N1++) {
	169	calcclk1 = crystal * N1 / M1;
	170	if (calcclk1 < minvco1)
	171	continue;
	172	if (calcclk1 > maxvco1)
	173	break;
	174
	175	for (M2 = minM2; M2 <= maxM2; M2++) {
	176	if (calcclk1/M2 < minU2)
	177	break;
	178	if (calcclk1/M2 > maxU2)
	179	continue;
	180
	181	/* add calcclk1/2 to round better */
	182	N2 = (clkP * M2 + calcclk1/2) / calcclk1;
	183	if (N2 < minN2)
	184	continue;
	185	if (N2 > maxN2)
	186	break;
	187
	188	if (!fixedgain2) {
	189	if (chip_version < 0x60)
	190	if (N2/M2 < 4 \|\| N2/M2 > 10)
	191	continue;
	192
	193	calcclk2 = calcclk1 * N2 / M2;
	194	if (calcclk2 < minvco2)
	195	break;
	196	if (calcclk2 > maxvco2)
	197	continue;
	198	} else
	199	calcclk2 = calcclk1;
	200
	201	calcclkout = calcclk2 >> log2P;
202	delta = abs(calcclkout - clk);
203	/* we do an exhaustive search rather than terminating
204	* on an optimality condition...
205	*/
206	if (delta < bestdelta) {
207	bestdelta = delta;
208	bestclk = calcclkout;
209	*pN1 = N1;
210	*pM1 = M1;
211	*pN2 = N2;
212	*pM2 = M2;
213	*pP = log2P;
214	if (delta == 0) /* except this one */
215	return bestclk;
216	}
217	}
218	}
219	}
220
221	return bestclk;
222	}
223
224	int
7ada785f	225	nv04_pll_calc(struct nouveau_subdev subdev, struct nvbios_pll info, u32 freq,
70790f4f BS	226	int N1, int M1, int N2, int M2, int *P)
	227	{
	228	int ret;
	229
	230	if (!info->vco2.max_freq) {
7ada785f	231	ret = getMNP_single(subdev, info, freq, N1, M1, P);
70790f4f BS	232	*N2 = 1;
	233	*M2 = 1;
	234	} else {
7ada785f	235	ret = getMNP_double(subdev, info, freq, N1, M1, N2, M2, P);
70790f4f BS	236	}
	237
	238	if (!ret)
7ada785f	239	nv_error(subdev, "unable to compute acceptable pll values\n");
70790f4f BS	240	return ret;
70790f4f BS	241	}