This series adds HiSilicon true random number generator(TRNG)
driver in hw_random subsystem.
Signed-off-by: Zaibo Xu <xuzaibo@xxxxxxxxxx>
Signed-off-by: Weili Qian <qianweili@xxxxxxxxxx>
---
drivers/char/hw_random/Kconfig | 13 +++++
drivers/char/hw_random/Makefile | 1 +
drivers/char/hw_random/hisi-trng-v2.c | 99 +++++++++++++++++++++++++++++++++++
3 files changed, 113 insertions(+)
create mode 100644 drivers/char/hw_random/hisi-trng-v2.c
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 87a1c30..7c7fecf 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -308,6 +308,19 @@ config HW_RANDOM_HISI
If unsure, say Y.
+config HW_RANDOM_HISI_V2
+ tristate "HiSilicon True Random Number Generator V2 support"
+ depends on HW_RANDOM && ARM64 && ACPI
+ default HW_RANDOM
+ help
+ This driver provides kernel-side support for the True Random Number
+ Generator V2 hardware found on HiSilicon Hi1620 SoC.
+
+ To compile this driver as a module, choose M here: the
+ module will be called hisi-trng-v2.
+
+ If unsure, say Y.
+
config HW_RANDOM_ST
tristate "ST Microelectronics HW Random Number Generator support"
depends on HW_RANDOM && ARCH_STI
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 17b6d4e..a7801b4 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o
obj-$(CONFIG_HW_RANDOM_POWERNV) += powernv-rng.o
obj-$(CONFIG_HW_RANDOM_HISI) += hisi-rng.o
+obj-$(CONFIG_HW_RANDOM_HISI_V2) += hisi-trng-v2.o
obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o
obj-$(CONFIG_HW_RANDOM_IPROC_RNG200) += iproc-rng200.o
obj-$(CONFIG_HW_RANDOM_ST) += st-rng.o
diff --git a/drivers/char/hw_random/hisi-trng-v2.c b/drivers/char/hw_random/hisi-trng-v2.c
new file mode 100644
index 0000000..6a65b82
--- /dev/null
+++ b/drivers/char/hw_random/hisi-trng-v2.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
