thermal: tegra: split tegra_soctherm driver

Split most of the Tegra124 data and code into a Tegra124-specific
file.
Split most of the fuse-related code into a fuse-related source file.
This is in preparation for adding a Tegra210-specific driver in a
future patch.

Beyond the maintainability improvements, this is intended to separate
chip-specific ATE and characterization-related hacks into chip-specific
files, in the hopes that they won't pollute code for other chips.

Signed-off-by: Wei Ni <wni@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

drivers/thermal/tegra/soctherm-fuse.c

@@ -0,0 +1,158 @@
+/*
+ * 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
+
+/*
+ * Tegra12x, etc:
+ * 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 <wni@nvidia.com>");
+MODULE_DESCRIPTION("Tegra SOCTHERM fuse management");
+MODULE_LICENSE("GPL v2");