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-rw-r--r--drivers/thermal/tegra/soctherm-fuse.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/thermal/tegra/soctherm-fuse.c b/drivers/thermal/tegra/soctherm-fuse.c
new file mode 100644
index 0000000000..190f95280e
--- /dev/null
+++ b/drivers/thermal/tegra/soctherm-fuse.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014-2016, NVIDIA CORPORATION. All rights reserved.
+ */
+
+#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 <wni@nvidia.com>");
+MODULE_DESCRIPTION("Tegra SOCTHERM fuse management");
+MODULE_LICENSE("GPL v2");