| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Qualcomm ICE (Inline Crypto Engine) support. |
| * |
| * Copyright (c) 2013-2019, The Linux Foundation. All rights reserved. |
| * Copyright (c) 2019, Google LLC |
| * Copyright (c) 2023, Linaro Limited |
| */ |
| |
| #include <linux/bitfield.h> |
| #include <linux/cleanup.h> |
| #include <linux/clk.h> |
| #include <linux/delay.h> |
| #include <linux/iopoll.h> |
| #include <linux/of.h> |
| #include <linux/of_platform.h> |
| #include <linux/platform_device.h> |
| |
| #include <linux/firmware/qcom/qcom_scm.h> |
| |
| #include <soc/qcom/ice.h> |
| |
| #define AES_256_XTS_KEY_SIZE 64 |
| |
| /* QCOM ICE registers */ |
| #define QCOM_ICE_REG_VERSION 0x0008 |
| #define QCOM_ICE_REG_FUSE_SETTING 0x0010 |
| #define QCOM_ICE_REG_BIST_STATUS 0x0070 |
| #define QCOM_ICE_REG_ADVANCED_CONTROL 0x1000 |
| |
| /* BIST ("built-in self-test") status flags */ |
| #define QCOM_ICE_BIST_STATUS_MASK GENMASK(31, 28) |
| |
| #define QCOM_ICE_FUSE_SETTING_MASK 0x1 |
| #define QCOM_ICE_FORCE_HW_KEY0_SETTING_MASK 0x2 |
| #define QCOM_ICE_FORCE_HW_KEY1_SETTING_MASK 0x4 |
| |
| #define qcom_ice_writel(engine, val, reg) \ |
| writel((val), (engine)->base + (reg)) |
| |
| #define qcom_ice_readl(engine, reg) \ |
| readl((engine)->base + (reg)) |
| |
| struct qcom_ice { |
| struct device *dev; |
| void __iomem *base; |
| struct device_link *link; |
| |
| struct clk *core_clk; |
| }; |
| |
| static bool qcom_ice_check_supported(struct qcom_ice *ice) |
| { |
| u32 regval = qcom_ice_readl(ice, QCOM_ICE_REG_VERSION); |
| struct device *dev = ice->dev; |
| int major = FIELD_GET(GENMASK(31, 24), regval); |
| int minor = FIELD_GET(GENMASK(23, 16), regval); |
| int step = FIELD_GET(GENMASK(15, 0), regval); |
| |
| /* For now this driver only supports ICE version 3 and 4. */ |
| if (major != 3 && major != 4) { |
| dev_warn(dev, "Unsupported ICE version: v%d.%d.%d\n", |
| major, minor, step); |
| return false; |
| } |
| |
| dev_info(dev, "Found QC Inline Crypto Engine (ICE) v%d.%d.%d\n", |
| major, minor, step); |
| |
| /* If fuses are blown, ICE might not work in the standard way. */ |
| regval = qcom_ice_readl(ice, QCOM_ICE_REG_FUSE_SETTING); |
| if (regval & (QCOM_ICE_FUSE_SETTING_MASK | |
| QCOM_ICE_FORCE_HW_KEY0_SETTING_MASK | |
| QCOM_ICE_FORCE_HW_KEY1_SETTING_MASK)) { |
| dev_warn(dev, "Fuses are blown; ICE is unusable!\n"); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static void qcom_ice_low_power_mode_enable(struct qcom_ice *ice) |
| { |
| u32 regval; |
| |
| regval = qcom_ice_readl(ice, QCOM_ICE_REG_ADVANCED_CONTROL); |
| |
| /* Enable low power mode sequence */ |
| regval |= 0x7000; |
| qcom_ice_writel(ice, regval, QCOM_ICE_REG_ADVANCED_CONTROL); |
| } |
| |
| static void qcom_ice_optimization_enable(struct qcom_ice *ice) |
| { |
| u32 regval; |
| |
| /* ICE Optimizations Enable Sequence */ |
| regval = qcom_ice_readl(ice, QCOM_ICE_REG_ADVANCED_CONTROL); |
| regval |= 0xd807100; |
| /* ICE HPG requires delay before writing */ |
| udelay(5); |
| qcom_ice_writel(ice, regval, QCOM_ICE_REG_ADVANCED_CONTROL); |
| udelay(5); |
| } |
| |
| /* |
| * Wait until the ICE BIST (built-in self-test) has completed. |
| * |
| * This may be necessary before ICE can be used. |
| * Note that we don't really care whether the BIST passed or failed; |
| * we really just want to make sure that it isn't still running. This is |
| * because (a) the BIST is a FIPS compliance thing that never fails in |
| * practice, (b) ICE is documented to reject crypto requests if the BIST |
| * fails, so we needn't do it in software too, and (c) properly testing |
| * storage encryption requires testing the full storage stack anyway, |
| * and not relying on hardware-level self-tests. |
| */ |
| static int qcom_ice_wait_bist_status(struct qcom_ice *ice) |
| { |
| u32 regval; |
| int err; |
| |
| err = readl_poll_timeout(ice->base + QCOM_ICE_REG_BIST_STATUS, |
| regval, !(regval & QCOM_ICE_BIST_STATUS_MASK), |
| 50, 5000); |
| if (err) |
| dev_err(ice->dev, "Timed out waiting for ICE self-test to complete\n"); |
| |
| return err; |
| } |
| |
| int qcom_ice_enable(struct qcom_ice *ice) |
| { |
| qcom_ice_low_power_mode_enable(ice); |
| qcom_ice_optimization_enable(ice); |
| |
| return qcom_ice_wait_bist_status(ice); |
| } |
| EXPORT_SYMBOL_GPL(qcom_ice_enable); |
| |
| int qcom_ice_resume(struct qcom_ice *ice) |
| { |
| struct device *dev = ice->dev; |
| int err; |
| |
| err = clk_prepare_enable(ice->core_clk); |
| if (err) { |
| dev_err(dev, "failed to enable core clock (%d)\n", |
| err); |
| return err; |
| } |
| |
| return qcom_ice_wait_bist_status(ice); |
| } |
| EXPORT_SYMBOL_GPL(qcom_ice_resume); |
| |
| int qcom_ice_suspend(struct qcom_ice *ice) |
| { |
| clk_disable_unprepare(ice->core_clk); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(qcom_ice_suspend); |
| |
| int qcom_ice_program_key(struct qcom_ice *ice, |
| u8 algorithm_id, u8 key_size, |
| const u8 crypto_key[], u8 data_unit_size, |
| int slot) |
| { |
| struct device *dev = ice->dev; |
| union { |
| u8 bytes[AES_256_XTS_KEY_SIZE]; |
| u32 words[AES_256_XTS_KEY_SIZE / sizeof(u32)]; |
| } key; |
| int i; |
| int err; |
| |
| /* Only AES-256-XTS has been tested so far. */ |
| if (algorithm_id != QCOM_ICE_CRYPTO_ALG_AES_XTS || |
| key_size != QCOM_ICE_CRYPTO_KEY_SIZE_256) { |
| dev_err_ratelimited(dev, |
| "Unhandled crypto capability; algorithm_id=%d, key_size=%d\n", |
| algorithm_id, key_size); |
| return -EINVAL; |
| } |
| |
| memcpy(key.bytes, crypto_key, AES_256_XTS_KEY_SIZE); |
| |
| /* The SCM call requires that the key words are encoded in big endian */ |
| for (i = 0; i < ARRAY_SIZE(key.words); i++) |
| __cpu_to_be32s(&key.words[i]); |
| |
| err = qcom_scm_ice_set_key(slot, key.bytes, AES_256_XTS_KEY_SIZE, |
| QCOM_SCM_ICE_CIPHER_AES_256_XTS, |
| data_unit_size); |
| |
| memzero_explicit(&key, sizeof(key)); |
| |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(qcom_ice_program_key); |
| |
| int qcom_ice_evict_key(struct qcom_ice *ice, int slot) |
| { |
| return qcom_scm_ice_invalidate_key(slot); |
| } |
| EXPORT_SYMBOL_GPL(qcom_ice_evict_key); |
| |
| static struct qcom_ice *qcom_ice_create(struct device *dev, |
| void __iomem *base) |
| { |
| struct qcom_ice *engine; |
| |
| if (!qcom_scm_is_available()) |
| return ERR_PTR(-EPROBE_DEFER); |
| |
| if (!qcom_scm_ice_available()) { |
| dev_warn(dev, "ICE SCM interface not found\n"); |
| return NULL; |
| } |
| |
| engine = devm_kzalloc(dev, sizeof(*engine), GFP_KERNEL); |
| if (!engine) |
| return ERR_PTR(-ENOMEM); |
| |
| engine->dev = dev; |
| engine->base = base; |
| |
| /* |
| * Legacy DT binding uses different clk names for each consumer, |
| * so lets try those first. If none of those are a match, it means |
| * the we only have one clock and it is part of the dedicated DT node. |
| * Also, enable the clock before we check what HW version the driver |
| * supports. |
| */ |
| engine->core_clk = devm_clk_get_optional_enabled(dev, "ice_core_clk"); |
| if (!engine->core_clk) |
| engine->core_clk = devm_clk_get_optional_enabled(dev, "ice"); |
| if (!engine->core_clk) |
| engine->core_clk = devm_clk_get_enabled(dev, NULL); |
| if (IS_ERR(engine->core_clk)) |
| return ERR_CAST(engine->core_clk); |
| |
| if (!qcom_ice_check_supported(engine)) |
| return ERR_PTR(-EOPNOTSUPP); |
| |
| dev_dbg(dev, "Registered Qualcomm Inline Crypto Engine\n"); |
| |
| return engine; |
| } |
| |
| /** |
| * of_qcom_ice_get() - get an ICE instance from a DT node |
| * @dev: device pointer for the consumer device |
| * |
| * This function will provide an ICE instance either by creating one for the |
| * consumer device if its DT node provides the 'ice' reg range and the 'ice' |
| * clock (for legacy DT style). On the other hand, if consumer provides a |
| * phandle via 'qcom,ice' property to an ICE DT, the ICE instance will already |
| * be created and so this function will return that instead. |
| * |
| * Return: ICE pointer on success, NULL if there is no ICE data provided by the |
| * consumer or ERR_PTR() on error. |
| */ |
| struct qcom_ice *of_qcom_ice_get(struct device *dev) |
| { |
| struct platform_device *pdev = to_platform_device(dev); |
| struct qcom_ice *ice; |
| struct resource *res; |
| void __iomem *base; |
| |
| if (!dev || !dev->of_node) |
| return ERR_PTR(-ENODEV); |
| |
| /* |
| * In order to support legacy style devicetree bindings, we need |
| * to create the ICE instance using the consumer device and the reg |
| * range called 'ice' it provides. |
| */ |
| res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ice"); |
| if (res) { |
| base = devm_ioremap_resource(&pdev->dev, res); |
| if (IS_ERR(base)) |
| return ERR_CAST(base); |
| |
| /* create ICE instance using consumer dev */ |
| return qcom_ice_create(&pdev->dev, base); |
| } |
| |
| /* |
| * If the consumer node does not provider an 'ice' reg range |
| * (legacy DT binding), then it must at least provide a phandle |
| * to the ICE devicetree node, otherwise ICE is not supported. |
| */ |
| struct device_node *node __free(device_node) = of_parse_phandle(dev->of_node, |
| "qcom,ice", 0); |
| if (!node) |
| return NULL; |
| |
| pdev = of_find_device_by_node(node); |
| if (!pdev) { |
| dev_err(dev, "Cannot find device node %s\n", node->name); |
| return ERR_PTR(-EPROBE_DEFER); |
| } |
| |
| ice = platform_get_drvdata(pdev); |
| if (!ice) { |
| dev_err(dev, "Cannot get ice instance from %s\n", |
| dev_name(&pdev->dev)); |
| platform_device_put(pdev); |
| return ERR_PTR(-EPROBE_DEFER); |
| } |
| |
| ice->link = device_link_add(dev, &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER); |
| if (!ice->link) { |
| dev_err(&pdev->dev, |
| "Failed to create device link to consumer %s\n", |
| dev_name(dev)); |
| platform_device_put(pdev); |
| ice = ERR_PTR(-EINVAL); |
| } |
| |
| return ice; |
| } |
| EXPORT_SYMBOL_GPL(of_qcom_ice_get); |
| |
| static int qcom_ice_probe(struct platform_device *pdev) |
| { |
| struct qcom_ice *engine; |
| void __iomem *base; |
| |
| base = devm_platform_ioremap_resource(pdev, 0); |
| if (IS_ERR(base)) { |
| dev_warn(&pdev->dev, "ICE registers not found\n"); |
| return PTR_ERR(base); |
| } |
| |
| engine = qcom_ice_create(&pdev->dev, base); |
| if (IS_ERR(engine)) |
| return PTR_ERR(engine); |
| |
| platform_set_drvdata(pdev, engine); |
| |
| return 0; |
| } |
| |
| static const struct of_device_id qcom_ice_of_match_table[] = { |
| { .compatible = "qcom,inline-crypto-engine" }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, qcom_ice_of_match_table); |
| |
| static struct platform_driver qcom_ice_driver = { |
| .probe = qcom_ice_probe, |
| .driver = { |
| .name = "qcom-ice", |
| .of_match_table = qcom_ice_of_match_table, |
| }, |
| }; |
| |
| module_platform_driver(qcom_ice_driver); |
| |
| MODULE_DESCRIPTION("Qualcomm Inline Crypto Engine driver"); |
| MODULE_LICENSE("GPL"); |