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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2014-2016, NVIDIA CORPORATION. All rights reserved.4 */5 6#include <linux/module.h>7#include <linux/platform_device.h>8#include <soc/tegra/fuse.h>9 10#include "soctherm.h"11 12#define NOMINAL_CALIB_FT 10513#define NOMINAL_CALIB_CP 2514 15#define FUSE_TSENSOR_CALIB_CP_TS_BASE_MASK 0x1fff16#define FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK (0x1fff << 13)17#define FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT 1318 19#define FUSE_TSENSOR_COMMON 0x18020 21/*22 * Tegra210: Layout of bits in FUSE_TSENSOR_COMMON:23 * 3 2 1 024 * 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 1 025 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+26 * | BASE_FT | BASE_CP | SHFT_FT | SHIFT_CP |27 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+28 *29 * Tegra12x, etc:30 * In chips prior to Tegra210, this fuse was incorrectly sized as 26 bits,31 * and didn't hold SHIFT_CP in [31:26]. Therefore these missing six bits32 * were obtained via the FUSE_SPARE_REALIGNMENT_REG register [5:0].33 *34 * FUSE_TSENSOR_COMMON:35 * 3 2 1 036 * 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 1 037 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+38 * |-----------| SHFT_FT | BASE_FT | BASE_CP |39 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+40 *41 * FUSE_SPARE_REALIGNMENT_REG:42 * 3 2 1 043 * 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 1 044 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+45 * |---------------------------------------------------| SHIFT_CP |46 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+47 */48 49#define CALIB_COEFFICIENT 1000000LL50 51/**52 * div64_s64_precise() - wrapper for div64_s64()53 * @a: the dividend54 * @b: the divisor55 *56 * Implements division with fairly accurate rounding instead of truncation by57 * shifting the dividend to the left by 16 so that the quotient has a58 * much higher precision.59 *60 * Return: the quotient of a / b.61 */62static s64 div64_s64_precise(s64 a, s32 b)63{64 s64 r, al;65 66 /* Scale up for increased precision division */67 al = a << 16;68 69 r = div64_s64(al * 2 + 1, 2 * b);70 return r >> 16;71}72 73int tegra_calc_shared_calib(const struct tegra_soctherm_fuse *tfuse,74 struct tsensor_shared_calib *shared)75{76 u32 val;77 s32 shifted_cp, shifted_ft;78 int err;79 80 err = tegra_fuse_readl(FUSE_TSENSOR_COMMON, &val);81 if (err)82 return err;83 84 shared->base_cp = (val & tfuse->fuse_base_cp_mask) >>85 tfuse->fuse_base_cp_shift;86 shared->base_ft = (val & tfuse->fuse_base_ft_mask) >>87 tfuse->fuse_base_ft_shift;88 89 shifted_ft = (val & tfuse->fuse_shift_ft_mask) >>90 tfuse->fuse_shift_ft_shift;91 shifted_ft = sign_extend32(shifted_ft, 4);92 93 if (tfuse->fuse_spare_realignment) {94 err = tegra_fuse_readl(tfuse->fuse_spare_realignment, &val);95 if (err)96 return err;97 }98 99 shifted_cp = sign_extend32(val, 5);100 101 shared->actual_temp_cp = 2 * NOMINAL_CALIB_CP + shifted_cp;102 shared->actual_temp_ft = 2 * NOMINAL_CALIB_FT + shifted_ft;103 104 return 0;105}106 107int tegra_calc_tsensor_calib(const struct tegra_tsensor *sensor,108 const struct tsensor_shared_calib *shared,109 u32 *calibration)110{111 const struct tegra_tsensor_group *sensor_group;112 u32 val, calib;113 s32 actual_tsensor_ft, actual_tsensor_cp;114 s32 delta_sens, delta_temp;115 s32 mult, div;116 s16 therma, thermb;117 s64 temp;118 int err;119 120 sensor_group = sensor->group;121 122 err = tegra_fuse_readl(sensor->calib_fuse_offset, &val);123 if (err)124 return err;125 126 actual_tsensor_cp = (shared->base_cp * 64) + sign_extend32(val, 12);127 val = (val & FUSE_TSENSOR_CALIB_FT_TS_BASE_MASK) >>128 FUSE_TSENSOR_CALIB_FT_TS_BASE_SHIFT;129 actual_tsensor_ft = (shared->base_ft * 32) + sign_extend32(val, 12);130 131 delta_sens = actual_tsensor_ft - actual_tsensor_cp;132 delta_temp = shared->actual_temp_ft - shared->actual_temp_cp;133 134 mult = sensor_group->pdiv * sensor->config->tsample_ate;135 div = sensor->config->tsample * sensor_group->pdiv_ate;136 137 temp = (s64)delta_temp * (1LL << 13) * mult;138 therma = div64_s64_precise(temp, (s64)delta_sens * div);139 140 temp = ((s64)actual_tsensor_ft * shared->actual_temp_cp) -141 ((s64)actual_tsensor_cp * shared->actual_temp_ft);142 thermb = div64_s64_precise(temp, delta_sens);143 144 temp = (s64)therma * sensor->fuse_corr_alpha;145 therma = div64_s64_precise(temp, CALIB_COEFFICIENT);146 147 temp = (s64)thermb * sensor->fuse_corr_alpha + sensor->fuse_corr_beta;148 thermb = div64_s64_precise(temp, CALIB_COEFFICIENT);149 150 calib = ((u16)therma << SENSOR_CONFIG2_THERMA_SHIFT) |151 ((u16)thermb << SENSOR_CONFIG2_THERMB_SHIFT);152 153 *calibration = calib;154 155 return 0;156}157 158MODULE_AUTHOR("Wei Ni <wni@nvidia.com>");159MODULE_DESCRIPTION("Tegra SOCTHERM fuse management");160MODULE_LICENSE("GPL v2");161