[PATCH 2/4] crypto: hisilicon/trng - add HiSilicon TRNG driver support

From: Weili Qian
Date: Fri Nov 20 2020 - 04:06:19 EST


Move existing char/hw_random/hisi-trng-v2.c to crypto/hisilicon/trng.c.

Signed-off-by: Weili Qian <qianweili@xxxxxxxxxx>
Reviewed-by: Zaibo Xu <xuzaibo@xxxxxxxxxx>
---
arch/arm64/configs/defconfig | 1 +
drivers/crypto/hisilicon/Kconfig | 7 +++
drivers/crypto/hisilicon/Makefile | 1 +
drivers/crypto/hisilicon/trng/Makefile | 2 +
drivers/crypto/hisilicon/trng/trng.c | 99 ++++++++++++++++++++++++++++++++++
5 files changed, 110 insertions(+)
create mode 100644 drivers/crypto/hisilicon/trng/Makefile
create mode 100644 drivers/crypto/hisilicon/trng/trng.c

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 17a2df6..646c3b4 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -1081,6 +1081,7 @@ CONFIG_CRYPTO_DEV_CCREE=m
CONFIG_CRYPTO_DEV_HISI_SEC2=m
CONFIG_CRYPTO_DEV_HISI_ZIP=m
CONFIG_CRYPTO_DEV_HISI_HPRE=m
+CONFIG_CRYPTO_DEV_HISI_TRNG=m
CONFIG_CMA_SIZE_MBYTES=32
CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_INFO=y
diff --git a/drivers/crypto/hisilicon/Kconfig b/drivers/crypto/hisilicon/Kconfig
index 9c3b3ca..2cd3298 100644
--- a/drivers/crypto/hisilicon/Kconfig
+++ b/drivers/crypto/hisilicon/Kconfig
@@ -71,3 +71,10 @@ config CRYPTO_DEV_HISI_HPRE
help
Support for HiSilicon HPRE(High Performance RSA Engine)
accelerator, which can accelerate RSA and DH algorithms.
+
+config CRYPTO_DEV_HISI_TRNG
+ tristate "Support for HISI TRNG Driver"
+ depends on ARM64 && ACPI
+ select HW_RANDOM
+ help
+ Support for HiSilicon TRNG Driver.
diff --git a/drivers/crypto/hisilicon/Makefile b/drivers/crypto/hisilicon/Makefile
index 7f5f74c..1e89269 100644
--- a/drivers/crypto/hisilicon/Makefile
+++ b/drivers/crypto/hisilicon/Makefile
@@ -5,3 +5,4 @@ obj-$(CONFIG_CRYPTO_DEV_HISI_SEC2) += sec2/
obj-$(CONFIG_CRYPTO_DEV_HISI_QM) += hisi_qm.o
hisi_qm-objs = qm.o sgl.o
obj-$(CONFIG_CRYPTO_DEV_HISI_ZIP) += zip/
+obj-$(CONFIG_CRYPTO_DEV_HISI_TRNG) += trng/
diff --git a/drivers/crypto/hisilicon/trng/Makefile b/drivers/crypto/hisilicon/trng/Makefile
new file mode 100644
index 0000000..d909079
--- /dev/null
+++ b/drivers/crypto/hisilicon/trng/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_CRYPTO_DEV_HISI_TRNG) += hisi-trng-v2.o
+hisi-trng-v2-objs = trng.o
diff --git a/drivers/crypto/hisilicon/trng/trng.c b/drivers/crypto/hisilicon/trng/trng.c
new file mode 100644
index 0000000..6a65b82
--- /dev/null
+++ b/drivers/crypto/hisilicon/trng/trng.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 HiSilicon Limited. */
+
+#include <linux/acpi.h>
+#include <linux/err.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/random.h>
+
+#define HISI_TRNG_REG 0x00F0
+#define HISI_TRNG_BYTES 4
+#define HISI_TRNG_QUALITY 512
+#define SLEEP_US 10
+#define TIMEOUT_US 10000
+
+struct hisi_trng {
+ void __iomem *base;
+ struct hwrng rng;
+};
+
+static int hisi_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
+{
+ struct hisi_trng *trng;
+ int currsize = 0;
+ u32 val = 0;
+ u32 ret;
+
+ trng = container_of(rng, struct hisi_trng, rng);
+
+ do {
+ ret = readl_poll_timeout(trng->base + HISI_TRNG_REG, val,
+ val, SLEEP_US, TIMEOUT_US);
+ if (ret)
+ return currsize;
+
+ if (max - currsize >= HISI_TRNG_BYTES) {
+ memcpy(buf + currsize, &val, HISI_TRNG_BYTES);
+ currsize += HISI_TRNG_BYTES;
+ if (currsize == max)
+ return currsize;
+ continue;
+ }
+
+ /* copy remaining bytes */
+ memcpy(buf + currsize, &val, max - currsize);
+ currsize = max;
+ } while (currsize < max);
+
+ return currsize;
+}
+
+static int hisi_trng_probe(struct platform_device *pdev)
+{
+ struct hisi_trng *trng;
+ int ret;
+
+ trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL);
+ if (!trng)
+ return -ENOMEM;
+
+ trng->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(trng->base))
+ return PTR_ERR(trng->base);
+
+ trng->rng.name = pdev->name;
+ trng->rng.read = hisi_trng_read;
+ trng->rng.quality = HISI_TRNG_QUALITY;
+
+ ret = devm_hwrng_register(&pdev->dev, &trng->rng);
+ if (ret)
+ dev_err(&pdev->dev, "failed to register hwrng!\n");
+
+ return ret;
+}
+
+static const struct acpi_device_id hisi_trng_acpi_match[] = {
+ { "HISI02B3", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, hisi_trng_acpi_match);
+
+static struct platform_driver hisi_trng_driver = {
+ .probe = hisi_trng_probe,
+ .driver = {
+ .name = "hisi-trng-v2",
+ .acpi_match_table = ACPI_PTR(hisi_trng_acpi_match),
+ },
+};
+
+module_platform_driver(hisi_trng_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Weili Qian <qianweili@xxxxxxxxxx>");
+MODULE_AUTHOR("Zaibo Xu <xuzaibo@xxxxxxxxxx>");
+MODULE_DESCRIPTION("HiSilicon true random number generator V2 driver");
--
2.8.1