This is follow patch on top of [1] to add hwrng support for newer platform with trng capability. [1] https://lore.kernel.org/lkml/20230824-topic-sm8550-rng-v2-4-dfcafbb16a3e@xxxxxxxxxx/ Signed-off-by: Om Prakash Singh <quic_omprsing@xxxxxxxxxxx> --- drivers/crypto/qcom-rng.c | 72 ++++++++++++++++++++++++++++++++++----- 1 file changed, 63 insertions(+), 9 deletions(-) diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c index fb54b8cfc35f..f78ffdcc66ec 100644 --- a/drivers/crypto/qcom-rng.c +++ b/drivers/crypto/qcom-rng.c @@ -13,6 +13,7 @@ #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> +#include <linux/hw_random.h> /* Device specific register offsets */ #define PRNG_DATA_OUT 0x0000 @@ -32,13 +33,18 @@ struct qcom_rng { struct mutex lock; void __iomem *base; struct clk *clk; - unsigned int skip_init; + struct qcom_rng_of_data *of_data; }; struct qcom_rng_ctx { struct qcom_rng *rng; }; +struct qcom_rng_of_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) @@ -70,7 +76,7 @@ static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max) } } while (currsize < max); - return 0; + return currsize; } static int qcom_rng_generate(struct crypto_rng *tfm, @@ -79,7 +85,8 @@ static int qcom_rng_generate(struct crypto_rng *tfm, { struct qcom_rng_ctx *ctx = crypto_rng_ctx(tfm); struct qcom_rng *rng = ctx->rng; - int ret; + int ret = -EFAULT; + int read_size = 0; ret = clk_prepare_enable(rng->clk); if (ret) @@ -87,11 +94,14 @@ static int qcom_rng_generate(struct crypto_rng *tfm, mutex_lock(&rng->lock); - ret = qcom_rng_read(rng, dstn, dlen); + read_size = qcom_rng_read(rng, dstn, dlen); mutex_unlock(&rng->lock); clk_disable_unprepare(rng->clk); + if (read_size == dlen) + ret = 0; + return ret; } @@ -101,6 +111,16 @@ static int qcom_rng_seed(struct crypto_rng *tfm, const u8 *seed, return 0; } +static int qcom_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait) +{ + int ret; + struct qcom_rng *qrng; + + qrng = (struct qcom_rng *)rng->priv; + ret = qcom_rng_read(qrng, data, max); + return ret; +} + static int qcom_rng_enable(struct qcom_rng *rng) { u32 val; @@ -136,7 +156,7 @@ static int qcom_rng_init(struct crypto_tfm *tfm) ctx->rng = qcom_rng_dev; - if (!ctx->rng->skip_init) + if (!ctx->rng->of_data->skip_init) return qcom_rng_enable(ctx->rng); return 0; @@ -157,9 +177,16 @@ static struct rng_alg qcom_rng_alg = { } }; +static struct hwrng qcom_hwrng = { + .name = "qcom-hwrng", + .read = qcom_hwrng_read, + .quality = 1024, +}; + static int qcom_rng_probe(struct platform_device *pdev) { struct qcom_rng *rng; + const struct qcom_rng_of_data *data; int ret; rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL); @@ -177,7 +204,8 @@ static int qcom_rng_probe(struct platform_device *pdev) if (IS_ERR(rng->clk)) return PTR_ERR(rng->clk); - rng->skip_init = (unsigned long)device_get_match_data(&pdev->dev); + data = of_device_get_match_data(&pdev->dev); + rng->of_data = (struct qcom_rng_of_data *)data; qcom_rng_dev = rng; ret = crypto_register_rng(&qcom_rng_alg); @@ -185,6 +213,14 @@ static int qcom_rng_probe(struct platform_device *pdev) dev_err(&pdev->dev, "Register crypto rng failed: %d\n", ret); qcom_rng_dev = NULL; } + if (rng->of_data->hwrng_support) { + qcom_hwrng.priv = (unsigned long)qcom_rng_dev; + ret = hwrng_register(&qcom_hwrng); + if (ret) { + dev_err(&pdev->dev, "Register hwrng failed: %d\n", ret); + qcom_rng_dev = NULL; + } + } return ret; } @@ -193,11 +229,29 @@ static int qcom_rng_remove(struct platform_device *pdev) { crypto_unregister_rng(&qcom_rng_alg); + if (qcom_rng_dev->of_data->hwrng_support) + hwrng_unregister(&qcom_hwrng); + qcom_rng_dev = NULL; return 0; } +struct qcom_rng_of_data qcom_prng_of_data = { + .skip_init = false, + .hwrng_support = false, +}; + +struct qcom_rng_of_data qcom_prng_ee_of_data = { + .skip_init = true, + .hwrng_support = false, +}; + +struct qcom_rng_of_data qcom_trng_of_data = { + .skip_init = true, + .hwrng_support = true, +}; + static const struct acpi_device_id __maybe_unused qcom_rng_acpi_match[] = { { .id = "QCOM8160", .driver_data = 1 }, {} @@ -205,9 +259,9 @@ static const struct acpi_device_id __maybe_unused qcom_rng_acpi_match[] = { MODULE_DEVICE_TABLE(acpi, qcom_rng_acpi_match); static const struct of_device_id __maybe_unused qcom_rng_of_match[] = { - { .compatible = "qcom,prng", .data = (void *)0}, - { .compatible = "qcom,prng-ee", .data = (void *)1}, - { .compatible = "qcom,trng", .data = (void *)1}, + { .compatible = "qcom,prng", .data = &qcom_prng_of_data }, + { .compatible = "qcom,prng-ee", .data = &qcom_prng_ee_of_data }, + { .compatible = "qcom,trng", .data = &qcom_trng_of_data }, {} }; MODULE_DEVICE_TABLE(of, qcom_rng_of_match); -- 2.25.1
