This is follow patch on top of [1] to add hwrng support for newer
platform with trng capability.
[1] https://lore.kernel.org/lkml/[email protected]/
Signed-off-by: Om Prakash Singh <[email protected]>
---
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
On 01/09/2023 15:15, Om Prakash Singh wrote:
> This is follow patch on top of [1] to add hwrng support for newer
> platform with trng capability.
Please use subject prefixes matching the subsystem.
Best regards,
Krzysztof
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 <[email protected]>
---
Changes in V2:
- Updated patch to fix the return value from qcom_rng_generate() to be
consistent with current implementation
- Updated patch to make it more concise
- Removed unnecessary use local variable and it's initialization
- Updated patch to use devm_hwrng_register() instead of hwrng_register()
- Updated subject line of the patch
This patch is depends on [1]
[1] https://lore.kernel.org/lkml/[email protected]/
drivers/crypto/qcom-rng.c | 65 ++++++++++++++++++++++++++++++++++-----
1 file changed, 58 insertions(+), 7 deletions(-)
diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c
index fb54b8cfc35f..e5a574a3cc59 100644
--- a/drivers/crypto/qcom-rng.c
+++ b/drivers/crypto/qcom-rng.c
@@ -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>
@@ -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,
@@ -92,6 +98,9 @@ static int qcom_rng_generate(struct crypto_rng *tfm,
mutex_unlock(&rng->lock);
clk_disable_unprepare(rng->clk);
+ if (ret == dlen)
+ ret = 0;
+
return ret;
}
@@ -101,6 +110,13 @@ 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)
+{
+ struct qcom_rng *qrng = (struct qcom_rng *)rng->priv;
+
+ return qcom_rng_read(qrng, data, max);
+}
+
static int qcom_rng_enable(struct qcom_rng *rng)
{
u32 val;
@@ -136,7 +152,7 @@ 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;
@@ -157,6 +173,12 @@ 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;
@@ -177,15 +199,29 @@ 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) {
+ qcom_hwrng.priv = (unsigned long)qcom_rng_dev;
+ ret = devm_hwrng_register(&pdev->dev, &qcom_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 +234,21 @@ static int qcom_rng_remove(struct platform_device *pdev)
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 +256,9 @@ 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
On 9/22/2023 8:46 PM, Bjorn Andersson wrote:
> On Wed, Sep 20, 2023 at 08:34:08AM +0530, Om Prakash Singh wrote:
>> 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 <[email protected]>
>> ---
>>
>> Changes in V2:
>> - Updated patch to fix the return value from qcom_rng_generate() to be
>> consistent with current implementation
>
> As far as I can tell you didn't change this, see below.
>
>> - Updated patch to make it more concise
>> - Removed unnecessary use local variable and it's initialization
>> - Updated patch to use devm_hwrng_register() instead of hwrng_register()
>> - Updated subject line of the patch
>>
>> This patch is depends on [1]
>> [1] https://lore.kernel.org/lkml/[email protected]/
>>
>> drivers/crypto/qcom-rng.c | 65 ++++++++++++++++++++++++++++++++++-----
>> 1 file changed, 58 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c
>> index fb54b8cfc35f..e5a574a3cc59 100644
>> --- a/drivers/crypto/qcom-rng.c
>> +++ b/drivers/crypto/qcom-rng.c
>> @@ -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>
>> @@ -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;
>
> As I pointed out in my previous review, if the qcom_rng_read() is
> requested to read a number of bytes (max) that is not evenly divisible
> with 4 (WORD_SZ) the loop will exit without accounting for the last
> bytes copied...
I will update implementation to account currsize for accounting
remaining bytes
>> }
>>
>> static int qcom_rng_generate(struct crypto_rng *tfm,
>> @@ -92,6 +98,9 @@ static int qcom_rng_generate(struct crypto_rng *tfm,
>> mutex_unlock(&rng->lock);
>> clk_disable_unprepare(rng->clk);
>>
>> + if (ret == dlen)
>
> ...this means that if dlen % 4, you're changing the return value of this
> function from 0 to dlen.
I will Update logic for success case return value.
>
>> + ret = 0;
>> +
>> return ret;
>> }
>>
>> @@ -101,6 +110,13 @@ 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)
>> +{
>> + struct qcom_rng *qrng = (struct qcom_rng *)rng->priv;
>
> You missed Herbert's request in [1], which I presume implies that
> qcom_hwrng should be moved into struct qcom_rng, which would mean that
> you can get the qrng by container_of().
>
> [1] https://lore.kernel.org/lkml/[email protected]/
I will address this comment is my next patch set V3.
>> +
>> + return qcom_rng_read(qrng, data, max);
>> +}
>> +
>> static int qcom_rng_enable(struct qcom_rng *rng)
>> {
>> u32 val;
>> @@ -136,7 +152,7 @@ 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;
>> @@ -157,6 +173,12 @@ static struct rng_alg qcom_rng_alg = {
>> }
>> };
>>
>> +static struct hwrng qcom_hwrng = {
>> + .name = "qcom-hwrng",
>> + .read = qcom_hwrng_read,
>> + .quality = 1024,
>> +};
>
> Which would mean not adding this static global variable...
>
> Regards,
> Bjorn