diff options
Diffstat (limited to 'drivers/crypto/qcom-rng.c')
| -rw-r--r-- | drivers/crypto/qcom-rng.c | 158 |
1 files changed, 19 insertions, 139 deletions
diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c index 7058bd98f9e9..4d046caafe5b 100644 --- a/drivers/crypto/qcom-rng.c +++ b/drivers/crypto/qcom-rng.c @@ -3,10 +3,8 @@ // // Based on msm-rng.c and downstream driver -#include <crypto/internal/rng.h> #include <linux/acpi.h> #include <linux/clk.h> -#include <linux/crypto.h> #include <linux/hw_random.h> #include <linux/io.h> #include <linux/iopoll.h> @@ -32,24 +30,15 @@ #define QCOM_TRNG_QUALITY 1024 struct qcom_rng { - struct mutex lock; void __iomem *base; struct clk *clk; struct hwrng hwrng; - struct qcom_rng_match_data *match_data; -}; - -struct qcom_rng_ctx { - struct qcom_rng *rng; }; struct qcom_rng_match_data { - bool skip_init; bool hwrng_support; }; -static struct qcom_rng *qcom_rng_dev; - static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max) { unsigned int currsize = 0; @@ -80,37 +69,6 @@ static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max) return currsize; } -static int qcom_rng_generate(struct crypto_rng *tfm, - const u8 *src, unsigned int slen, - u8 *dstn, unsigned int dlen) -{ - struct qcom_rng_ctx *ctx = crypto_rng_ctx(tfm); - struct qcom_rng *rng = ctx->rng; - int ret; - - ret = clk_prepare_enable(rng->clk); - if (ret) - return ret; - - mutex_lock(&rng->lock); - - ret = qcom_rng_read(rng, dstn, dlen); - - mutex_unlock(&rng->lock); - clk_disable_unprepare(rng->clk); - - if (ret >= 0) - ret = 0; - - return ret; -} - -static int qcom_rng_seed(struct crypto_rng *tfm, const u8 *seed, - unsigned int slen) -{ - return 0; -} - static int qcom_hwrng_init(struct hwrng *hwrng) { struct qcom_rng *qrng = container_of(hwrng, struct qcom_rng, hwrng); @@ -132,74 +90,26 @@ static void qcom_hwrng_cleanup(struct hwrng *hwrng) clk_disable_unprepare(qrng->clk); } -static int qcom_rng_enable(struct qcom_rng *rng) -{ - u32 val; - int ret; - - ret = clk_prepare_enable(rng->clk); - if (ret) - return ret; - - /* Enable PRNG only if it is not already enabled */ - val = readl_relaxed(rng->base + PRNG_CONFIG); - if (val & PRNG_CONFIG_HW_ENABLE) - goto already_enabled; - - val = readl_relaxed(rng->base + PRNG_LFSR_CFG); - val &= ~PRNG_LFSR_CFG_MASK; - val |= PRNG_LFSR_CFG_CLOCKS; - writel(val, rng->base + PRNG_LFSR_CFG); - - val = readl_relaxed(rng->base + PRNG_CONFIG); - val |= PRNG_CONFIG_HW_ENABLE; - writel(val, rng->base + PRNG_CONFIG); - -already_enabled: - clk_disable_unprepare(rng->clk); - - return 0; -} - -static int qcom_rng_init(struct crypto_tfm *tfm) -{ - struct qcom_rng_ctx *ctx = crypto_tfm_ctx(tfm); - - ctx->rng = qcom_rng_dev; - - if (!ctx->rng->match_data->skip_init) - return qcom_rng_enable(ctx->rng); - - return 0; -} - -static struct rng_alg qcom_rng_alg = { - .generate = qcom_rng_generate, - .seed = qcom_rng_seed, - .seedsize = 0, - .base = { - .cra_name = "stdrng", - .cra_driver_name = "qcom-rng", - .cra_flags = CRYPTO_ALG_TYPE_RNG, - .cra_priority = 300, - .cra_ctxsize = sizeof(struct qcom_rng_ctx), - .cra_module = THIS_MODULE, - .cra_init = qcom_rng_init, - } -}; - static int qcom_rng_probe(struct platform_device *pdev) { + const struct qcom_rng_match_data *match_data; struct qcom_rng *rng; int ret; + match_data = device_get_match_data(&pdev->dev); + if (match_data == NULL || !match_data->hwrng_support) { + dev_info(&pdev->dev, "TRNG support not detected\n"); + /* + * In this case the driver does nothing except the dev_info(), + * but bind the device anyway to avoid effects on GCC state. + */ + return 0; + } + rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL); if (!rng) return -ENOMEM; - platform_set_drvdata(pdev, rng); - mutex_init(&rng->lock); - rng->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(rng->base)) return PTR_ERR(rng->base); @@ -208,55 +118,26 @@ static int qcom_rng_probe(struct platform_device *pdev) if (IS_ERR(rng->clk)) return PTR_ERR(rng->clk); - rng->match_data = (struct qcom_rng_match_data *)device_get_match_data(&pdev->dev); - - qcom_rng_dev = rng; - ret = crypto_register_rng(&qcom_rng_alg); - if (ret) { - dev_err(&pdev->dev, "Register crypto rng failed: %d\n", ret); - qcom_rng_dev = NULL; - return ret; - } - - if (rng->match_data->hwrng_support) { - rng->hwrng.name = "qcom_hwrng"; - rng->hwrng.init = qcom_hwrng_init; - rng->hwrng.read = qcom_hwrng_read; - rng->hwrng.cleanup = qcom_hwrng_cleanup; - rng->hwrng.quality = QCOM_TRNG_QUALITY; - ret = devm_hwrng_register(&pdev->dev, &rng->hwrng); - if (ret) { - dev_err(&pdev->dev, "Register hwrng failed: %d\n", ret); - qcom_rng_dev = NULL; - goto fail; - } - } - - return ret; -fail: - crypto_unregister_rng(&qcom_rng_alg); + rng->hwrng.name = "qcom_hwrng"; + rng->hwrng.init = qcom_hwrng_init; + rng->hwrng.read = qcom_hwrng_read; + rng->hwrng.cleanup = qcom_hwrng_cleanup; + rng->hwrng.quality = QCOM_TRNG_QUALITY; + ret = devm_hwrng_register(&pdev->dev, &rng->hwrng); + if (ret) + dev_err(&pdev->dev, "Register hwrng failed: %d\n", ret); return ret; } -static void qcom_rng_remove(struct platform_device *pdev) -{ - crypto_unregister_rng(&qcom_rng_alg); - - qcom_rng_dev = NULL; -} - static struct qcom_rng_match_data qcom_prng_match_data = { - .skip_init = false, .hwrng_support = false, }; static struct qcom_rng_match_data qcom_prng_ee_match_data = { - .skip_init = true, .hwrng_support = false, }; static struct qcom_rng_match_data qcom_trng_match_data = { - .skip_init = true, .hwrng_support = true, }; @@ -276,7 +157,6 @@ MODULE_DEVICE_TABLE(of, qcom_rng_of_match); static struct platform_driver qcom_rng_driver = { .probe = qcom_rng_probe, - .remove = qcom_rng_remove, .driver = { .name = KBUILD_MODNAME, .of_match_table = qcom_rng_of_match, |