nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

crypto: qcom-rng - Add hw_random interface support

Browse source 
Add hw_random interface support in qcom-rng driver as new IP block
in Qualcomm SoC has inbuilt NIST SP800 90B compliant entropic source
to generate true random number.

Keeping current rng_alg interface as well for random number generation
using Kernel Crypto API.

Signed-off-by: Om Prakash Singh <quic_omprsing@quicinc.com>
Reviewed-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Acked-by: Om Prakash Singh <quic_omprsing@quicinc.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Om Prakash Singh 2023-10-03 09:10:21 +02:00 committed by Herbert Xu
parent a4d7e9ec21
commit f29cd5bb64
1 changed files with 58 additions and 7 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

65
drivers/crypto/qcom-rng.c
View file

@ -7,6 +7,7 @@
#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>
#include <linux/kernel.h>
@ -28,17 +29,25 @@
#define WORD_SZ 4
#define QCOM_TRNG_QUALITY 1024
struct qcom_rng {
struct mutex lock;
void __iomem *base;
struct clk *clk;
unsigned int skip_init;
struct hwrng hwrng;
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)
@ -66,11 +75,11 @@ static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max)
} else {
/* copy only remaining bytes */
memcpy(data, &val, max - currsize);
break;
currsize = max;
}
} while (currsize < max);
return 0;
return currsize;
}
static int qcom_rng_generate(struct crypto_rng *tfm,
@ -92,6 +101,9 @@ static int qcom_rng_generate(struct crypto_rng *tfm,
mutex_unlock(&rng->lock);
clk_disable_unprepare(rng->clk);
if (ret >= 0)
ret = 0;
return ret;
}
@ -101,6 +113,13 @@ static int qcom_rng_seed(struct crypto_rng *tfm, const u8 *seed,
return 0;
}
static int qcom_hwrng_read(struct hwrng *hwrng, void *data, size_t max, bool wait)
{
struct qcom_rng *qrng = container_of(hwrng, struct qcom_rng, hwrng);
return qcom_rng_read(qrng, data, max);
}
static int qcom_rng_enable(struct qcom_rng *rng)
{
u32 val;
@ -136,7 +155,7 @@ 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;
@ -177,15 +196,31 @@ 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);
rng->of_data = (struct qcom_rng_of_data *)of_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->of_data->hwrng_support) {
rng->hwrng.name = "qcom_hwrng";
rng->hwrng.read = qcom_hwrng_read;
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);
return ret;
}
@ -198,6 +233,21 @@ static int qcom_rng_remove(struct platform_device *pdev)
return 0;
}
static struct qcom_rng_of_data qcom_prng_of_data = {
.skip_init = false,
.hwrng_support = false,
};
static struct qcom_rng_of_data qcom_prng_ee_of_data = {
.skip_init = true,
.hwrng_support = false,
};
static 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 },
{}
@ -205,8 +255,9 @@ 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,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);