// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2015 Srinivas Kandagatla */ #include #include #include #include #include #include #include #include #include #include /* Blow timer clock frequency in Mhz */ #define QFPROM_BLOW_TIMER_OFFSET 0x03c /* Amount of time required to hold charge to blow fuse in micro-seconds */ #define QFPROM_FUSE_BLOW_POLL_US 100 #define QFPROM_FUSE_BLOW_TIMEOUT_US 1000 #define QFPROM_BLOW_STATUS_OFFSET 0x048 #define QFPROM_BLOW_STATUS_BUSY 0x1 #define QFPROM_BLOW_STATUS_READY 0x0 #define QFPROM_ACCEL_OFFSET 0x044 #define QFPROM_VERSION_OFFSET 0x0 #define QFPROM_MAJOR_VERSION_SHIFT 28 #define QFPROM_MAJOR_VERSION_MASK GENMASK(31, QFPROM_MAJOR_VERSION_SHIFT) #define QFPROM_MINOR_VERSION_SHIFT 16 #define QFPROM_MINOR_VERSION_MASK GENMASK(27, QFPROM_MINOR_VERSION_SHIFT) static bool read_raw_data; module_param(read_raw_data, bool, 0644); MODULE_PARM_DESC(read_raw_data, "Read raw instead of corrected data"); /** * struct qfprom_soc_data - config that varies from SoC to SoC. * * @accel_value: Should contain qfprom accel value. * @qfprom_blow_timer_value: The timer value of qfprom when doing efuse blow. * @qfprom_blow_set_freq: The frequency required to set when we start the * fuse blowing. */ struct qfprom_soc_data { u32 accel_value; u32 qfprom_blow_timer_value; u32 qfprom_blow_set_freq; }; /** * struct qfprom_priv - structure holding qfprom attributes * * @qfpraw: iomapped memory space for qfprom-efuse raw address space. * @qfpconf: iomapped memory space for qfprom-efuse configuration address * space. * @qfpcorrected: iomapped memory space for qfprom corrected address space. * @qfpsecurity: iomapped memory space for qfprom security control space. * @dev: qfprom device structure. * @secclk: Clock supply. * @vcc: Regulator supply. * @soc_data: Data that for things that varies from SoC to SoC. */ struct qfprom_priv { void __iomem *qfpraw; void __iomem *qfpconf; void __iomem *qfpcorrected; void __iomem *qfpsecurity; struct device *dev; struct clk *secclk; struct regulator *vcc; const struct qfprom_soc_data *soc_data; }; /** * struct qfprom_touched_values - saved values to restore after blowing * * @clk_rate: The rate the clock was at before blowing. * @accel_val: The value of the accel reg before blowing. * @timer_val: The value of the timer before blowing. */ struct qfprom_touched_values { unsigned long clk_rate; u32 accel_val; u32 timer_val; }; /** * qfprom_disable_fuse_blowing() - Undo enabling of fuse blowing. * @priv: Our driver data. * @old: The data that was stashed from before fuse blowing. * * Resets the value of the blow timer, accel register and the clock * and voltage settings. * * Prints messages if there are errors but doesn't return an error code * since there's not much we can do upon failure. */ static void qfprom_disable_fuse_blowing(const struct qfprom_priv *priv, const struct qfprom_touched_values *old) { int ret; ret = regulator_disable(priv->vcc); if (ret) dev_warn(priv->dev, "Failed to disable regulator (ignoring)\n"); ret = clk_set_rate(priv->secclk, old->clk_rate); if (ret) dev_warn(priv->dev, "Failed to set clock rate for disable (ignoring)\n"); clk_disable_unprepare(priv->secclk); writel(old->timer_val, priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); writel(old->accel_val, priv->qfpconf + QFPROM_ACCEL_OFFSET); } /** * qfprom_enable_fuse_blowing() - Enable fuse blowing. * @priv: Our driver data. * @old: We'll stash stuff here to use when disabling. * * Sets the value of the blow timer, accel register and the clock * and voltage settings. * * Prints messages if there are errors so caller doesn't need to. * * Return: 0 or -err. */ static int qfprom_enable_fuse_blowing(const struct qfprom_priv *priv, struct qfprom_touched_values *old) { int ret; ret = clk_prepare_enable(priv->secclk); if (ret) { dev_err(priv->dev, "Failed to enable clock\n"); return ret; } old->clk_rate = clk_get_rate(priv->secclk); ret = clk_set_rate(priv->secclk, priv->soc_data->qfprom_blow_set_freq); if (ret) { dev_err(priv->dev, "Failed to set clock rate for enable\n"); goto err_clk_prepared; } ret = regulator_enable(priv->vcc); if (ret) { dev_err(priv->dev, "Failed to enable regulator\n"); goto err_clk_rate_set; } old->timer_val = readl(priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); old->accel_val = readl(priv->qfpconf + QFPROM_ACCEL_OFFSET); writel(priv->soc_data->qfprom_blow_timer_value, priv->qfpconf + QFPROM_BLOW_TIMER_OFFSET); writel(priv->soc_data->accel_value, priv->qfpconf + QFPROM_ACCEL_OFFSET); return 0; err_clk_rate_set: clk_set_rate(priv->secclk, old->clk_rate); err_clk_prepared: clk_disable_unprepare(priv->secclk); return ret; } /** * qfprom_efuse_reg_write() - Write to fuses. * @context: Our driver data. * @reg: The offset to write at. * @_val: Pointer to data to write. * @bytes: The number of bytes to write. * * Writes to fuses. WARNING: THIS IS PERMANENT. * * Return: 0 or -err. */ static int qfprom_reg_write(void *context, unsigned int reg, void *_val, size_t bytes) { struct qfprom_priv *priv = context; struct qfprom_touched_values old; int words = bytes / 4; u32 *value = _val; u32 blow_status; int ret; int i; dev_dbg(priv->dev, "Writing to raw qfprom region : %#010x of size: %zu\n", reg, bytes); /* * The hardware only allows us to write word at a time, but we can * read byte at a time. Until the nvmem framework allows a separate * word_size and stride for reading vs. writing, we'll enforce here. */ if (bytes % 4) { dev_err(priv->dev, "%zu is not an integral number of words\n", bytes); return -EINVAL; } if (reg % 4) { dev_err(priv->dev, "Invalid offset: %#x. Must be word aligned\n", reg); return -EINVAL; } ret = qfprom_enable_fuse_blowing(priv, &old); if (ret) return ret; ret = readl_relaxed_poll_timeout( priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET, blow_status, blow_status == QFPROM_BLOW_STATUS_READY, QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US); if (ret) { dev_err(priv->dev, "Timeout waiting for initial ready; aborting.\n"); goto exit_enabled_fuse_blowing; } for (i = 0; i < words; i++) writel(value[i], priv->qfpraw + reg + (i * 4)); ret = readl_relaxed_poll_timeout( priv->qfpconf + QFPROM_BLOW_STATUS_OFFSET, blow_status, blow_status == QFPROM_BLOW_STATUS_READY, QFPROM_FUSE_BLOW_POLL_US, QFPROM_FUSE_BLOW_TIMEOUT_US); /* Give an error, but not much we can do in this case */ if (ret) dev_err(priv->dev, "Timeout waiting for finish.\n"); exit_enabled_fuse_blowing: qfprom_disable_fuse_blowing(priv, &old); return ret; } static int qfprom_reg_read(void *context, unsigned int reg, void *_val, size_t bytes) { struct qfprom_priv *priv = context; u8 *val = _val; int i = 0, words = bytes; void __iomem *base = priv->qfpcorrected; if (read_raw_data && priv->qfpraw) base = priv->qfpraw; while (words--) *val++ = readb(base + reg + i++); return 0; } static const struct qfprom_soc_data qfprom_7_8_data = { .accel_value = 0xD10, .qfprom_blow_timer_value = 25, .qfprom_blow_set_freq = 4800000, }; static int qfprom_probe(struct platform_device *pdev) { struct nvmem_config econfig = { .name = "qfprom", .stride = 1, .word_size = 1, .id = NVMEM_DEVID_AUTO, .reg_read = qfprom_reg_read, }; struct device *dev = &pdev->dev; struct resource *res; struct nvmem_device *nvmem; struct qfprom_priv *priv; int ret; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; /* The corrected section is always provided */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); priv->qfpcorrected = devm_ioremap_resource(dev, res); if (IS_ERR(priv->qfpcorrected)) return PTR_ERR(priv->qfpcorrected); econfig.size = resource_size(res); econfig.dev = dev; econfig.priv = priv; priv->dev = dev; /* * If more than one region is provided then the OS has the ability * to write. */ res = platform_get_resource(pdev, IORESOURCE_MEM, 1); if (res) { u32 version; int major_version, minor_version; priv->qfpraw = devm_ioremap_resource(dev, res); if (IS_ERR(priv->qfpraw)) return PTR_ERR(priv->qfpraw); res = platform_get_resource(pdev, IORESOURCE_MEM, 2); priv->qfpconf = devm_ioremap_resource(dev, res); if (IS_ERR(priv->qfpconf)) return PTR_ERR(priv->qfpconf); res = platform_get_resource(pdev, IORESOURCE_MEM, 3); priv->qfpsecurity = devm_ioremap_resource(dev, res); if (IS_ERR(priv->qfpsecurity)) return PTR_ERR(priv->qfpsecurity); version = readl(priv->qfpsecurity + QFPROM_VERSION_OFFSET); major_version = (version & QFPROM_MAJOR_VERSION_MASK) >> QFPROM_MAJOR_VERSION_SHIFT; minor_version = (version & QFPROM_MINOR_VERSION_MASK) >> QFPROM_MINOR_VERSION_SHIFT; if (major_version == 7 && minor_version == 8) priv->soc_data = &qfprom_7_8_data; priv->vcc = devm_regulator_get(&pdev->dev, "vcc"); if (IS_ERR(priv->vcc)) return PTR_ERR(priv->vcc); priv->secclk = devm_clk_get(dev, "core"); if (IS_ERR(priv->secclk)) { ret = PTR_ERR(priv->secclk); if (ret != -EPROBE_DEFER) dev_err(dev, "Error getting clock: %d\n", ret); return ret; } /* Only enable writing if we have SoC data. */ if (priv->soc_data) econfig.reg_write = qfprom_reg_write; } nvmem = devm_nvmem_register(dev, &econfig); return PTR_ERR_OR_ZERO(nvmem); } static const struct of_device_id qfprom_of_match[] = { { .compatible = "qcom,qfprom",}, {/* sentinel */}, }; MODULE_DEVICE_TABLE(of, qfprom_of_match); static struct platform_driver qfprom_driver = { .probe = qfprom_probe, .driver = { .name = "qcom,qfprom", .of_match_table = qfprom_of_match, }, }; module_platform_driver(qfprom_driver); MODULE_AUTHOR("Srinivas Kandagatla "); MODULE_DESCRIPTION("Qualcomm QFPROM driver"); MODULE_LICENSE("GPL v2");