[linux.git] / drivers / thermal / tegra / soctherm-fuse.c

/*
 * Copyright (c) 2014-2016, NVIDIA CORPORATION.  All rights reserved.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <soc/tegra/fuse.h>

#include "soctherm.h"

#define NOMINAL_CALIB_FT			105
#define NOMINAL_CALIB_CP			25

#define FUSE_TSENSOR_CALIB_CP_TS_BASE_MASK	0x1fff
#define FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK	(0x1fff << 13)
#define FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT	13

#define FUSE_TSENSOR_COMMON			0x180

/*
 * Tegra210: Layout of bits in FUSE_TSENSOR_COMMON:
 *    3                   2                   1                   0
 *  1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |       BASE_FT       |      BASE_CP      | SHFT_FT | SHIFT_CP  |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * Tegra12x, etc:
 * In chips prior to Tegra210, this fuse was incorrectly sized as 26 bits,
 * and didn't hold SHIFT_CP in [31:26]. Therefore these missing six bits
 * were obtained via the FUSE_SPARE_REALIGNMENT_REG register [5:0].
 *
 * FUSE_TSENSOR_COMMON:
 *    3                   2                   1                   0
 *  1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |-----------| SHFT_FT |       BASE_FT       |      BASE_CP      |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * FUSE_SPARE_REALIGNMENT_REG:
 *    3                   2                   1                   0
 *  1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |---------------------------------------------------| SHIFT_CP  |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 */

#define CALIB_COEFFICIENT 1000000LL

/**
 * div64_s64_precise() - wrapper for div64_s64()
 * @a:  the dividend
 * @b:  the divisor
 *
 * Implements division with fairly accurate rounding instead of truncation by
 * shifting the dividend to the left by 16 so that the quotient has a
 * much higher precision.
 *
 * Return: the quotient of a / b.
 */
static s64 div64_s64_precise(s64 a, s32 b)
{
	s64 r, al;

	/* Scale up for increased precision division */
	al = a << 16;

	r = div64_s64(al * 2 + 1, 2 * b);
	return r >> 16;
}

int tegra_calc_shared_calib(const struct tegra_soctherm_fuse *tfuse,
			    struct tsensor_shared_calib *shared)
{
	u32 val;
	s32 shifted_cp, shifted_ft;
	int err;

	err = tegra_fuse_readl(FUSE_TSENSOR_COMMON, &val);
	if (err)
		return err;

	shared->base_cp = (val & tfuse->fuse_base_cp_mask) >>
			  tfuse->fuse_base_cp_shift;
	shared->base_ft = (val & tfuse->fuse_base_ft_mask) >>
			  tfuse->fuse_base_ft_shift;

	shifted_ft = (val & tfuse->fuse_shift_ft_mask) >>
		     tfuse->fuse_shift_ft_shift;
	shifted_ft = sign_extend32(shifted_ft, 4);

	if (tfuse->fuse_spare_realignment) {
		err = tegra_fuse_readl(tfuse->fuse_spare_realignment, &val);
		if (err)
			return err;
	}

	shifted_cp = sign_extend32(val, 5);

	shared->actual_temp_cp = 2 * NOMINAL_CALIB_CP + shifted_cp;
	shared->actual_temp_ft = 2 * NOMINAL_CALIB_FT + shifted_ft;

	return 0;
}

int tegra_calc_tsensor_calib(const struct tegra_tsensor *sensor,
			     const struct tsensor_shared_calib *shared,
			     u32 *calibration)
{
	const struct tegra_tsensor_group *sensor_group;
	u32 val, calib;
	s32 actual_tsensor_ft, actual_tsensor_cp;
	s32 delta_sens, delta_temp;
	s32 mult, div;
	s16 therma, thermb;
	s64 temp;
	int err;

	sensor_group = sensor->group;

	err = tegra_fuse_readl(sensor->calib_fuse_offset, &val);
	if (err)
		return err;

	actual_tsensor_cp = (shared->base_cp * 64) + sign_extend32(val, 12);
	val = (val & FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK) >>
	      FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT;
	actual_tsensor_ft = (shared->base_ft * 32) + sign_extend32(val, 12);

	delta_sens = actual_tsensor_ft - actual_tsensor_cp;
	delta_temp = shared->actual_temp_ft - shared->actual_temp_cp;

	mult = sensor_group->pdiv * sensor->config->tsample_ate;
	div = sensor->config->tsample * sensor_group->pdiv_ate;

	temp = (s64)delta_temp * (1LL << 13) * mult;
	therma = div64_s64_precise(temp, (s64)delta_sens * div);

	temp = ((s64)actual_tsensor_ft * shared->actual_temp_cp) -
		((s64)actual_tsensor_cp * shared->actual_temp_ft);
	thermb = div64_s64_precise(temp, delta_sens);

	temp = (s64)therma * sensor->fuse_corr_alpha;
	therma = div64_s64_precise(temp, CALIB_COEFFICIENT);

	temp = (s64)thermb * sensor->fuse_corr_alpha + sensor->fuse_corr_beta;
	thermb = div64_s64_precise(temp, CALIB_COEFFICIENT);

	calib = ((u16)therma << SENSOR_CONFIG2_THERMA_SHIFT) |
		((u16)thermb << SENSOR_CONFIG2_THERMB_SHIFT);

	*calibration = calib;

	return 0;
}

MODULE_AUTHOR("Wei Ni <[email protected]>");
MODULE_DESCRIPTION("Tegra SOCTHERM fuse management");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
65b6d57c WN	1	/*
	2	* Copyright (c) 2014-2016, NVIDIA CORPORATION. All rights reserved.
	3	*
	4	* This software is licensed under the terms of the GNU General Public
	5	* License version 2, as published by the Free Software Foundation, and
	6	* may be copied, distributed, and modified under those terms.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/platform_device.h>
	17	#include <soc/tegra/fuse.h>
	18
	19	#include "soctherm.h"
	20
	21	#define NOMINAL_CALIB_FT 105
	22	#define NOMINAL_CALIB_CP 25
	23
	24	#define FUSE_TSENSOR_CALIB_CP_TS_BASE_MASK 0x1fff
	25	#define FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK (0x1fff << 13)
	26	#define FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT 13
	27
	28	#define FUSE_TSENSOR_COMMON 0x180
	29
	30	/*
8204104f WN	31	* Tegra210: Layout of bits in FUSE_TSENSOR_COMMON:
	32	* 3 2 1 0
	33	* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
	34	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	35	* \| BASE_FT \| BASE_CP \| SHFT_FT \| SHIFT_CP \|
	36	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	37	*
65b6d57c	38	* Tegra12x, etc:
8204104f WN	39	* In chips prior to Tegra210, this fuse was incorrectly sized as 26 bits,
	40	* and didn't hold SHIFT_CP in [31:26]. Therefore these missing six bits
	41	* were obtained via the FUSE_SPARE_REALIGNMENT_REG register [5:0].
	42	*
65b6d57c WN	43	* FUSE_TSENSOR_COMMON:
	44	* 3 2 1 0
	45	* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
	46	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	47	* \|-----------\| SHFT_FT \| BASE_FT \| BASE_CP \|
	48	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	49	*
	50	* FUSE_SPARE_REALIGNMENT_REG:
	51	* 3 2 1 0
	52	* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
	53	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	54	* \|---------------------------------------------------\| SHIFT_CP \|
	55	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	56	*/
	57
	58	#define CALIB_COEFFICIENT 1000000LL
	59
	60	/**
	61	* div64_s64_precise() - wrapper for div64_s64()
	62	* @a: the dividend
	63	* @b: the divisor
	64	*
	65	* Implements division with fairly accurate rounding instead of truncation by
	66	* shifting the dividend to the left by 16 so that the quotient has a
	67	* much higher precision.
	68	*
	69	* Return: the quotient of a / b.
	70	*/
	71	static s64 div64_s64_precise(s64 a, s32 b)
	72	{
	73	s64 r, al;
	74
	75	/* Scale up for increased precision division */
	76	al = a << 16;
	77
	78	r = div64_s64(al * 2 + 1, 2 * b);
	79	return r >> 16;
	80	}
	81
	82	int tegra_calc_shared_calib(const struct tegra_soctherm_fuse *tfuse,
	83	struct tsensor_shared_calib *shared)
	84	{
	85	u32 val;
	86	s32 shifted_cp, shifted_ft;
	87	int err;
	88
	89	err = tegra_fuse_readl(FUSE_TSENSOR_COMMON, &val);
	90	if (err)
	91	return err;
	92
	93	shared->base_cp = (val & tfuse->fuse_base_cp_mask) >>
	94	tfuse->fuse_base_cp_shift;
	95	shared->base_ft = (val & tfuse->fuse_base_ft_mask) >>
	96	tfuse->fuse_base_ft_shift;
	97
	98	shifted_ft = (val & tfuse->fuse_shift_ft_mask) >>
	99	tfuse->fuse_shift_ft_shift;
	100	shifted_ft = sign_extend32(shifted_ft, 4);
	101
	102	if (tfuse->fuse_spare_realignment) {
	103	err = tegra_fuse_readl(tfuse->fuse_spare_realignment, &val);
	104	if (err)
	105	return err;
	106	}
107
108	shifted_cp = sign_extend32(val, 5);
109
110	shared->actual_temp_cp = 2 * NOMINAL_CALIB_CP + shifted_cp;
111	shared->actual_temp_ft = 2 * NOMINAL_CALIB_FT + shifted_ft;
112
113	return 0;
114	}
115
116	int tegra_calc_tsensor_calib(const struct tegra_tsensor *sensor,
117	const struct tsensor_shared_calib *shared,
118	u32 *calibration)
119	{
120	const struct tegra_tsensor_group *sensor_group;
121	u32 val, calib;
122	s32 actual_tsensor_ft, actual_tsensor_cp;
123	s32 delta_sens, delta_temp;
124	s32 mult, div;
125	s16 therma, thermb;
126	s64 temp;
127	int err;
128
129	sensor_group = sensor->group;
130
131	err = tegra_fuse_readl(sensor->calib_fuse_offset, &val);
132	if (err)
133	return err;
134
135	actual_tsensor_cp = (shared->base_cp * 64) + sign_extend32(val, 12);
136	val = (val & FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK) >>
137	FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT;
138	actual_tsensor_ft = (shared->base_ft * 32) + sign_extend32(val, 12);
139
140	delta_sens = actual_tsensor_ft - actual_tsensor_cp;
141	delta_temp = shared->actual_temp_ft - shared->actual_temp_cp;
142
143	mult = sensor_group->pdiv * sensor->config->tsample_ate;
144	div = sensor->config->tsample * sensor_group->pdiv_ate;
145
146	temp = (s64)delta_temp * (1LL << 13) * mult;
147	therma = div64_s64_precise(temp, (s64)delta_sens * div);
148
149	temp = ((s64)actual_tsensor_ft * shared->actual_temp_cp) -
150	((s64)actual_tsensor_cp * shared->actual_temp_ft);
151	thermb = div64_s64_precise(temp, delta_sens);
152
153	temp = (s64)therma * sensor->fuse_corr_alpha;
154	therma = div64_s64_precise(temp, CALIB_COEFFICIENT);
155
156	temp = (s64)thermb * sensor->fuse_corr_alpha + sensor->fuse_corr_beta;
157	thermb = div64_s64_precise(temp, CALIB_COEFFICIENT);
158
159	calib = ((u16)therma << SENSOR_CONFIG2_THERMA_SHIFT) \|
160	((u16)thermb << SENSOR_CONFIG2_THERMB_SHIFT);
161
162	*calibration = calib;
163
164	return 0;
165	}
166
167	MODULE_AUTHOR("Wei Ni <[email protected]>");
168	MODULE_DESCRIPTION("Tegra SOCTHERM fuse management");
169	MODULE_LICENSE("GPL v2");