| .. | .. |
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| 1 | +// SPDX-License-Identifier: GPL-2.0-only |
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| 1 | 2 | /* |
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| 2 | 3 | * Copyright (C) 2015 Srinivas Kandagatla <srinivas.kandagatla@linaro.org> |
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| 3 | | - * |
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| 4 | | - * This program is free software; you can redistribute it and/or modify |
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| 5 | | - * it under the terms of the GNU General Public License version 2 and |
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| 6 | | - * only version 2 as published by the Free Software Foundation. |
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| 7 | | - * |
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| 8 | | - * This program is distributed in the hope that it will be useful, |
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| 9 | | - * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 10 | | - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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| 11 | | - * GNU General Public License for more details. |
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| 12 | 4 | */ |
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| 13 | 5 | |
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| 6 | +#include <linux/clk.h> |
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| 14 | 7 | #include <linux/device.h> |
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| 8 | +#include <linux/io.h> |
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| 9 | +#include <linux/iopoll.h> |
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| 10 | +#include <linux/kernel.h> |
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| 15 | 11 | #include <linux/module.h> |
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| 16 | 12 | #include <linux/mod_devicetable.h> |
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| 17 | | -#include <linux/io.h> |
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| 18 | 13 | #include <linux/nvmem-provider.h> |
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| 19 | 14 | #include <linux/platform_device.h> |
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| 15 | +#include <linux/regulator/consumer.h> |
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| 20 | 16 | |
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| 21 | | -struct qfprom_priv { |
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| 22 | | - void __iomem *base; |
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| 17 | +/* Blow timer clock frequency in Mhz */ |
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| 18 | +#define QFPROM_BLOW_TIMER_OFFSET 0x03c |
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| 19 | + |
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| 20 | +/* Amount of time required to hold charge to blow fuse in micro-seconds */ |
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| 21 | +#define QFPROM_FUSE_BLOW_POLL_US 100 |
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| 22 | +#define QFPROM_FUSE_BLOW_TIMEOUT_US 1000 |
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| 23 | + |
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| 24 | +#define QFPROM_BLOW_STATUS_OFFSET 0x048 |
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| 25 | +#define QFPROM_BLOW_STATUS_BUSY 0x1 |
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| 26 | +#define QFPROM_BLOW_STATUS_READY 0x0 |
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| 27 | + |
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| 28 | +#define QFPROM_ACCEL_OFFSET 0x044 |
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| 29 | + |
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| 30 | +#define QFPROM_VERSION_OFFSET 0x0 |
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| 31 | +#define QFPROM_MAJOR_VERSION_SHIFT 28 |
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| 32 | +#define QFPROM_MAJOR_VERSION_MASK GENMASK(31, QFPROM_MAJOR_VERSION_SHIFT) |
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| 33 | +#define QFPROM_MINOR_VERSION_SHIFT 16 |
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| 34 | +#define QFPROM_MINOR_VERSION_MASK GENMASK(27, QFPROM_MINOR_VERSION_SHIFT) |
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| 35 | + |
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| 36 | +static bool read_raw_data; |
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| 37 | +module_param(read_raw_data, bool, 0644); |
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| 38 | +MODULE_PARM_DESC(read_raw_data, "Read raw instead of corrected data"); |
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| 39 | + |
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| 40 | +/** |
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| 41 | + * struct qfprom_soc_data - config that varies from SoC to SoC. |
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| 42 | + * |
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| 43 | + * @accel_value: Should contain qfprom accel value. |
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| 44 | + * @qfprom_blow_timer_value: The timer value of qfprom when doing efuse blow. |
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| 45 | + * @qfprom_blow_set_freq: The frequency required to set when we start the |
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| 46 | + * fuse blowing. |
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| 47 | + */ |
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| 48 | +struct qfprom_soc_data { |
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| 49 | + u32 accel_value; |
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| 50 | + u32 qfprom_blow_timer_value; |
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| 51 | + u32 qfprom_blow_set_freq; |
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| 23 | 52 | }; |
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| 53 | + |
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| 54 | +/** |
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| 55 | + * struct qfprom_priv - structure holding qfprom attributes |
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| 56 | + * |
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| 57 | + * @qfpraw: iomapped memory space for qfprom-efuse raw address space. |
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| 58 | + * @qfpconf: iomapped memory space for qfprom-efuse configuration address |
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| 59 | + * space. |
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| 60 | + * @qfpcorrected: iomapped memory space for qfprom corrected address space. |
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| 61 | + * @qfpsecurity: iomapped memory space for qfprom security control space. |
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| 62 | + * @dev: qfprom device structure. |
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| 63 | + * @secclk: Clock supply. |
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| 64 | + * @vcc: Regulator supply. |
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| 65 | + * @soc_data: Data that for things that varies from SoC to SoC. |
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| 66 | + */ |
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| 67 | +struct qfprom_priv { |
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| 68 | + void __iomem *qfpraw; |
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| 69 | + void __iomem *qfpconf; |
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| 70 | + void __iomem *qfpcorrected; |
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| 71 | + void __iomem *qfpsecurity; |
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| 72 | + struct device *dev; |
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| 73 | + struct clk *secclk; |
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| 74 | + struct regulator *vcc; |
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| 75 | + const struct qfprom_soc_data *soc_data; |
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| 76 | +}; |
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| 77 | + |
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| 78 | +/** |
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| 79 | + * struct qfprom_touched_values - saved values to restore after blowing |
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| 80 | + * |
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| 81 | + * @clk_rate: The rate the clock was at before blowing. |
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| 82 | + * @accel_val: The value of the accel reg before blowing. |
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| 83 | + * @timer_val: The value of the timer before blowing. |
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| 84 | + */ |
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| 85 | +struct qfprom_touched_values { |
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| 86 | + unsigned long clk_rate; |
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| 87 | + u32 accel_val; |
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| 88 | + u32 timer_val; |
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| 89 | +}; |
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| 90 | + |
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| 91 | +/** |
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| 92 | + * qfprom_disable_fuse_blowing() - Undo enabling of fuse blowing. |
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| 93 | + * @priv: Our driver data. |
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| 94 | + * @old: The data that was stashed from before fuse blowing. |
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| 95 | + * |
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| 96 | + * Resets the value of the blow timer, accel register and the clock |
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| 97 | + * and voltage settings. |
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| 98 | + * |
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| 99 | + * Prints messages if there are errors but doesn't return an error code |
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| 100 | + * since there's not much we can do upon failure. |
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| 101 | + */ |
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| 102 | +static void qfprom_disable_fuse_blowing(const struct qfprom_priv *priv, |
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| 103 | + const struct qfprom_touched_values *old) |
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| 104 | +{ |
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| 105 | + int ret; |
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| 106 | + |
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| 107 | + writel(old->timer_val, priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); |
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| 108 | + writel(old->accel_val, priv->qfpconf + QFPROM_ACCEL_OFFSET); |
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| 109 | + |
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| 110 | + /* |
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| 111 | + * This may be a shared rail and may be able to run at a lower rate |
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| 112 | + * when we're not blowing fuses. At the moment, the regulator framework |
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| 113 | + * applies voltage constraints even on disabled rails, so remove our |
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| 114 | + * constraints and allow the rail to be adjusted by other users. |
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| 115 | + */ |
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| 116 | + ret = regulator_set_voltage(priv->vcc, 0, INT_MAX); |
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| 117 | + if (ret) |
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| 118 | + dev_warn(priv->dev, "Failed to set 0 voltage (ignoring)\n"); |
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| 119 | + |
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| 120 | + ret = regulator_disable(priv->vcc); |
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| 121 | + if (ret) |
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| 122 | + dev_warn(priv->dev, "Failed to disable regulator (ignoring)\n"); |
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| 123 | + |
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| 124 | + ret = clk_set_rate(priv->secclk, old->clk_rate); |
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| 125 | + if (ret) |
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| 126 | + dev_warn(priv->dev, |
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| 127 | + "Failed to set clock rate for disable (ignoring)\n"); |
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| 128 | + |
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| 129 | + clk_disable_unprepare(priv->secclk); |
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| 130 | +} |
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| 131 | + |
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| 132 | +/** |
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| 133 | + * qfprom_enable_fuse_blowing() - Enable fuse blowing. |
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| 134 | + * @priv: Our driver data. |
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| 135 | + * @old: We'll stash stuff here to use when disabling. |
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| 136 | + * |
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| 137 | + * Sets the value of the blow timer, accel register and the clock |
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| 138 | + * and voltage settings. |
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| 139 | + * |
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| 140 | + * Prints messages if there are errors so caller doesn't need to. |
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| 141 | + * |
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| 142 | + * Return: 0 or -err. |
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| 143 | + */ |
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| 144 | +static int qfprom_enable_fuse_blowing(const struct qfprom_priv *priv, |
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| 145 | + struct qfprom_touched_values *old) |
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| 146 | +{ |
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| 147 | + int ret; |
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| 148 | + |
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| 149 | + ret = clk_prepare_enable(priv->secclk); |
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| 150 | + if (ret) { |
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| 151 | + dev_err(priv->dev, "Failed to enable clock\n"); |
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| 152 | + return ret; |
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| 153 | + } |
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| 154 | + |
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| 155 | + old->clk_rate = clk_get_rate(priv->secclk); |
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| 156 | + ret = clk_set_rate(priv->secclk, priv->soc_data->qfprom_blow_set_freq); |
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| 157 | + if (ret) { |
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| 158 | + dev_err(priv->dev, "Failed to set clock rate for enable\n"); |
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| 159 | + goto err_clk_prepared; |
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| 160 | + } |
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| 161 | + |
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| 162 | + /* |
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| 163 | + * Hardware requires 1.8V min for fuse blowing; this may be |
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| 164 | + * a rail shared do don't specify a max--regulator constraints |
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| 165 | + * will handle. |
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| 166 | + */ |
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| 167 | + ret = regulator_set_voltage(priv->vcc, 1800000, INT_MAX); |
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| 168 | + if (ret) { |
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| 169 | + dev_err(priv->dev, "Failed to set 1.8 voltage\n"); |
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| 170 | + goto err_clk_rate_set; |
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| 171 | + } |
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| 172 | + |
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| 173 | + ret = regulator_enable(priv->vcc); |
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| 174 | + if (ret) { |
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| 175 | + dev_err(priv->dev, "Failed to enable regulator\n"); |
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| 176 | + goto err_clk_rate_set; |
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| 177 | + } |
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| 178 | + |
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| 179 | + old->timer_val = readl(priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); |
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| 180 | + old->accel_val = readl(priv->qfpconf + QFPROM_ACCEL_OFFSET); |
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| 181 | + writel(priv->soc_data->qfprom_blow_timer_value, |
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| 182 | + priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); |
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| 183 | + writel(priv->soc_data->accel_value, |
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| 184 | + priv->qfpconf + QFPROM_ACCEL_OFFSET); |
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| 185 | + |
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| 186 | + return 0; |
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| 187 | + |
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| 188 | +err_clk_rate_set: |
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| 189 | + clk_set_rate(priv->secclk, old->clk_rate); |
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| 190 | +err_clk_prepared: |
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| 191 | + clk_disable_unprepare(priv->secclk); |
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| 192 | + return ret; |
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| 193 | +} |
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| 194 | + |
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| 195 | +/** |
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| 196 | + * qfprom_efuse_reg_write() - Write to fuses. |
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| 197 | + * @context: Our driver data. |
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| 198 | + * @reg: The offset to write at. |
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| 199 | + * @_val: Pointer to data to write. |
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| 200 | + * @bytes: The number of bytes to write. |
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| 201 | + * |
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| 202 | + * Writes to fuses. WARNING: THIS IS PERMANENT. |
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| 203 | + * |
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| 204 | + * Return: 0 or -err. |
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| 205 | + */ |
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| 206 | +static int qfprom_reg_write(void *context, unsigned int reg, void *_val, |
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| 207 | + size_t bytes) |
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| 208 | +{ |
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| 209 | + struct qfprom_priv *priv = context; |
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| 210 | + struct qfprom_touched_values old; |
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| 211 | + int words = bytes / 4; |
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| 212 | + u32 *value = _val; |
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| 213 | + u32 blow_status; |
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| 214 | + int ret; |
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| 215 | + int i; |
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| 216 | + |
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| 217 | + dev_dbg(priv->dev, |
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| 218 | + "Writing to raw qfprom region : %#010x of size: %zu\n", |
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| 219 | + reg, bytes); |
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| 220 | + |
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| 221 | + /* |
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| 222 | + * The hardware only allows us to write word at a time, but we can |
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| 223 | + * read byte at a time. Until the nvmem framework allows a separate |
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| 224 | + * word_size and stride for reading vs. writing, we'll enforce here. |
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| 225 | + */ |
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| 226 | + if (bytes % 4) { |
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| 227 | + dev_err(priv->dev, |
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| 228 | + "%zu is not an integral number of words\n", bytes); |
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| 229 | + return -EINVAL; |
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| 230 | + } |
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| 231 | + if (reg % 4) { |
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| 232 | + dev_err(priv->dev, |
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| 233 | + "Invalid offset: %#x. Must be word aligned\n", reg); |
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| 234 | + return -EINVAL; |
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| 235 | + } |
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| 236 | + |
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| 237 | + ret = qfprom_enable_fuse_blowing(priv, &old); |
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| 238 | + if (ret) |
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| 239 | + return ret; |
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| 240 | + |
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| 241 | + ret = readl_relaxed_poll_timeout( |
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| 242 | + priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET, |
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| 243 | + blow_status, blow_status == QFPROM_BLOW_STATUS_READY, |
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| 244 | + QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US); |
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| 245 | + |
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| 246 | + if (ret) { |
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| 247 | + dev_err(priv->dev, |
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| 248 | + "Timeout waiting for initial ready; aborting.\n"); |
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| 249 | + goto exit_enabled_fuse_blowing; |
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| 250 | + } |
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| 251 | + |
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| 252 | + for (i = 0; i < words; i++) |
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| 253 | + writel(value[i], priv->qfpraw + reg + (i * 4)); |
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| 254 | + |
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| 255 | + ret = readl_relaxed_poll_timeout( |
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| 256 | + priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET, |
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| 257 | + blow_status, blow_status == QFPROM_BLOW_STATUS_READY, |
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| 258 | + QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US); |
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| 259 | + |
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| 260 | + /* Give an error, but not much we can do in this case */ |
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| 261 | + if (ret) |
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| 262 | + dev_err(priv->dev, "Timeout waiting for finish.\n"); |
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| 263 | + |
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| 264 | +exit_enabled_fuse_blowing: |
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| 265 | + qfprom_disable_fuse_blowing(priv, &old); |
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| 266 | + |
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| 267 | + return ret; |
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| 268 | +} |
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| 24 | 269 | |
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| 25 | 270 | static int qfprom_reg_read(void *context, |
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| 26 | 271 | unsigned int reg, void *_val, size_t bytes) |
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| .. | .. |
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| 28 | 273 | struct qfprom_priv *priv = context; |
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| 29 | 274 | u8 *val = _val; |
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| 30 | 275 | int i = 0, words = bytes; |
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| 276 | + void __iomem *base = priv->qfpcorrected; |
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| 277 | + |
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| 278 | + if (read_raw_data && priv->qfpraw) |
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| 279 | + base = priv->qfpraw; |
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| 31 | 280 | |
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| 32 | 281 | while (words--) |
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| 33 | | - *val++ = readb(priv->base + reg + i++); |
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| 282 | + *val++ = readb(base + reg + i++); |
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| 34 | 283 | |
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| 35 | 284 | return 0; |
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| 36 | 285 | } |
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| 37 | 286 | |
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| 38 | | -static struct nvmem_config econfig = { |
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| 39 | | - .name = "qfprom", |
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| 40 | | - .stride = 1, |
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| 41 | | - .word_size = 1, |
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| 42 | | - .reg_read = qfprom_reg_read, |
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| 287 | +static const struct qfprom_soc_data qfprom_7_8_data = { |
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| 288 | + .accel_value = 0xD10, |
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| 289 | + .qfprom_blow_timer_value = 25, |
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| 290 | + .qfprom_blow_set_freq = 4800000, |
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| 43 | 291 | }; |
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| 44 | 292 | |
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| 45 | 293 | static int qfprom_probe(struct platform_device *pdev) |
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| 46 | 294 | { |
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| 295 | + struct nvmem_config econfig = { |
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| 296 | + .name = "qfprom", |
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| 297 | + .stride = 1, |
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| 298 | + .word_size = 1, |
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| 299 | + .id = NVMEM_DEVID_AUTO, |
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| 300 | + .reg_read = qfprom_reg_read, |
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| 301 | + }; |
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| 47 | 302 | struct device *dev = &pdev->dev; |
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| 48 | 303 | struct resource *res; |
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| 49 | 304 | struct nvmem_device *nvmem; |
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| 50 | 305 | struct qfprom_priv *priv; |
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| 306 | + int ret; |
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| 51 | 307 | |
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| 52 | 308 | priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); |
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| 53 | 309 | if (!priv) |
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| 54 | 310 | return -ENOMEM; |
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| 55 | 311 | |
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| 312 | + /* The corrected section is always provided */ |
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| 56 | 313 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
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| 57 | | - priv->base = devm_ioremap_resource(dev, res); |
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| 58 | | - if (IS_ERR(priv->base)) |
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| 59 | | - return PTR_ERR(priv->base); |
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| 314 | + priv->qfpcorrected = devm_ioremap_resource(dev, res); |
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| 315 | + if (IS_ERR(priv->qfpcorrected)) |
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| 316 | + return PTR_ERR(priv->qfpcorrected); |
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| 60 | 317 | |
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| 61 | 318 | econfig.size = resource_size(res); |
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| 62 | 319 | econfig.dev = dev; |
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| 63 | 320 | econfig.priv = priv; |
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| 64 | 321 | |
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| 322 | + priv->dev = dev; |
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| 323 | + |
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| 324 | + /* |
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| 325 | + * If more than one region is provided then the OS has the ability |
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| 326 | + * to write. |
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| 327 | + */ |
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| 328 | + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); |
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| 329 | + if (res) { |
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| 330 | + u32 version; |
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| 331 | + int major_version, minor_version; |
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| 332 | + |
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| 333 | + priv->qfpraw = devm_ioremap_resource(dev, res); |
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| 334 | + if (IS_ERR(priv->qfpraw)) |
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| 335 | + return PTR_ERR(priv->qfpraw); |
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| 336 | + res = platform_get_resource(pdev, IORESOURCE_MEM, 2); |
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| 337 | + priv->qfpconf = devm_ioremap_resource(dev, res); |
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| 338 | + if (IS_ERR(priv->qfpconf)) |
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| 339 | + return PTR_ERR(priv->qfpconf); |
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| 340 | + res = platform_get_resource(pdev, IORESOURCE_MEM, 3); |
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| 341 | + priv->qfpsecurity = devm_ioremap_resource(dev, res); |
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| 342 | + if (IS_ERR(priv->qfpsecurity)) |
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| 343 | + return PTR_ERR(priv->qfpsecurity); |
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| 344 | + |
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| 345 | + version = readl(priv->qfpsecurity + QFPROM_VERSION_OFFSET); |
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| 346 | + major_version = (version & QFPROM_MAJOR_VERSION_MASK) >> |
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| 347 | + QFPROM_MAJOR_VERSION_SHIFT; |
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| 348 | + minor_version = (version & QFPROM_MINOR_VERSION_MASK) >> |
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| 349 | + QFPROM_MINOR_VERSION_SHIFT; |
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| 350 | + |
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| 351 | + if (major_version == 7 && minor_version == 8) |
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| 352 | + priv->soc_data = &qfprom_7_8_data; |
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| 353 | + |
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| 354 | + priv->vcc = devm_regulator_get(&pdev->dev, "vcc"); |
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| 355 | + if (IS_ERR(priv->vcc)) |
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| 356 | + return PTR_ERR(priv->vcc); |
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| 357 | + |
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| 358 | + priv->secclk = devm_clk_get(dev, "core"); |
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| 359 | + if (IS_ERR(priv->secclk)) { |
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| 360 | + ret = PTR_ERR(priv->secclk); |
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| 361 | + if (ret != -EPROBE_DEFER) |
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| 362 | + dev_err(dev, "Error getting clock: %d\n", ret); |
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| 363 | + return ret; |
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| 364 | + } |
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| 365 | + |
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| 366 | + /* Only enable writing if we have SoC data. */ |
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| 367 | + if (priv->soc_data) |
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| 368 | + econfig.reg_write = qfprom_reg_write; |
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| 369 | + } |
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| 370 | + |
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| 65 | 371 | nvmem = devm_nvmem_register(dev, &econfig); |
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| 66 | 372 | |
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| 67 | 373 | return PTR_ERR_OR_ZERO(nvmem); |
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