The Cavium ThunderX SoC has a hardware random number generator.
This driver provides support using the HWRNG framework.
Signed-off-by: Omer Khaliq <okhaliq@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ananth Jasty <Ananth.Jasty@xxxxxxxxxx>
Acked-by: David Daney <david.daney@xxxxxxxxxx>
---
drivers/char/hw_random/Kconfig | 13 +++++
drivers/char/hw_random/Makefile | 1 +
drivers/char/hw_random/cavium-rng-vf.c | 102 ++++++++++++++++++++++++++++++++
drivers/char/hw_random/cavium-rng.c | 103 +++++++++++++++++++++++++++++++++
4 files changed, 219 insertions(+)
create mode 100644 drivers/char/hw_random/cavium-rng-vf.c
create mode 100644 drivers/char/hw_random/cavium-rng.c
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 56ad5a5..fb9c7ad 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -410,6 +410,19 @@ config HW_RANDOM_MESON
If unsure, say Y.
+config HW_RANDOM_CAVIUM
+ tristate "Cavium ThunderX Random Number Generator support"
+ depends on HW_RANDOM && PCI && (ARM64 || (COMPILE_TEST && 64BIT))
+ default HW_RANDOM
+ ---help---
+ This driver provides kernel-side support for the Random Number
+ Generator hardware found on Cavium SoCs.
+
+ To compile this driver as a module, choose M here: the
+ module will be called cavium_rng.
+
+ If unsure, say Y.
+
endif # HW_RANDOM
config UML_RANDOM
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 04bb0b0..5f52b1e 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -35,3 +35,4 @@ obj-$(CONFIG_HW_RANDOM_XGENE) += xgene-rng.o
obj-$(CONFIG_HW_RANDOM_STM32) += stm32-rng.o
obj-$(CONFIG_HW_RANDOM_PIC32) += pic32-rng.o
obj-$(CONFIG_HW_RANDOM_MESON) += meson-rng.o
+obj-$(CONFIG_HW_RANDOM_CAVIUM) += cavium-rng.o cavium-rng-vf.o
diff --git a/drivers/char/hw_random/cavium-rng-vf.c b/drivers/char/hw_random/cavium-rng-vf.c
new file mode 100644
index 0000000..8e80bce
--- /dev/null
+++ b/drivers/char/hw_random/cavium-rng-vf.c
@@ -0,0 +1,102 @@
+/*
+ * Hardware Random Number Generator support for Cavium, Inc.
+ * Thunder processor family.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2016 Cavium, Inc.
+ */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/pci_ids.h>
+#include <linux/gfp.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+
+struct cavium_rng {
+ struct hwrng ops;
+ void __iomem *result;
+};
+
+/* Read data from the RNG unit */
+static int cavium_rng_read(struct hwrng *rng, void *dat, size_t max, bool wait)
+{
+ struct cavium_rng *p = container_of(rng, struct cavium_rng, ops);
+ unsigned int size = max;
+
+ while (size >= 8) {
+ *((u64 *)dat) = readq(p->result);
+ size -= 8;
+ dat += 8;
+ }
+ while (size > 0) {
+ *((u8 *)dat) = readb(p->result);
+ size--;
+ dat++;
+ }
+ return max;
+}
+
+/* Map Cavium RNG to an HWRNG object */
+static int cavium_rng_probe_vf(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct cavium_rng *rng;
+ int ret;
+
+ rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
+ if (!rng)
+ return -ENOMEM;
+
+ /* Map the RNG result */
+ rng->result = pcim_iomap(pdev, 0, 0);
+ if (!rng->result) {
+ dev_err(&pdev->dev, "Error iomap failed retrieving result.\n");
+ return -ENOMEM;
+ }
+
+ rng->ops.name = "cavium rng";
+ rng->ops.read = cavium_rng_read;
+ rng->ops.quality = 1000;
+
+ pci_set_drvdata(pdev, rng);
+
+ ret = hwrng_register(&rng->ops);
+ if (ret) {
+ dev_err(&pdev->dev, "Error registering device as HWRNG.\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+/* Remove the VF */
+void cavium_rng_remove_vf(struct pci_dev *pdev)
+{
+ struct cavium_rng *rng;
+
+ rng = pci_get_drvdata(pdev);
+ hwrng_unregister(&rng->ops);
+}
+
+static const struct pci_device_id cavium_rng_vf_id_table[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa033), 0, 0, 0},
+ {0,},
+};
+MODULE_DEVICE_TABLE(pci, cavium_rng_vf_id_table);
+
+static struct pci_driver cavium_rng_vf_driver = {
+ .name = "cavium_rng_vf",
+ .id_table = cavium_rng_vf_id_table,
+ .probe = cavium_rng_probe_vf,
+ .remove = cavium_rng_remove_vf,
+};
+module_pci_driver(cavium_rng_vf_driver);
+
+MODULE_AUTHOR("Omer Khaliq");
+MODULE_LICENSE("GPL");
diff --git a/drivers/char/hw_random/cavium-rng.c b/drivers/char/hw_random/cavium-rng.c
new file mode 100644
index 0000000..7f09ee4
--- /dev/null
+++ b/drivers/char/hw_random/cavium-rng.c
@@ -0,0 +1,103 @@
+/*
+ * Hardware Random Number Generator support for Cavium Inc.
+ * Thunder processor family.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2016 Cavium, Inc.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/pci_ids.h>
+#include <linux/gfp.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/pci-ats.h>
+
+#define THUNDERX_RNM_ENT_EN 0x1
+#define THUNDERX_RNM_RNG_EN 0x2
+
+struct cavium_rng_pf {
+ void __iomem *control_status;
+};
+
+
+/* Enable the RNG hardware and activate the VF */
+static int cavium_rng_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct cavium_rng_pf *rng;
+ int iov_err;
+
+
+ rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
+ if (!rng)
+ return -ENOMEM;
+
+ /*Map the RNG control */
+ rng->control_status = pcim_iomap(pdev, 0, 0);
+ if (!rng->control_status) {
+ dev_err(&pdev->dev,
+ "Error iomap failed retrieving control_status.\n");
+ return -ENOMEM;
+ }
+
+ /* Enable the RNG hardware and entropy source */
+ writeq(THUNDERX_RNM_RNG_EN | THUNDERX_RNM_ENT_EN,
+ rng->control_status);
+
+ pci_set_drvdata(pdev, rng);
+
+ /* Fix for improper link id reported for cn88XX */
+ if (pdev->subsystem_device == 0xa118)
+ pci_sriov_fdl_override(pdev, pdev->devfn);
+
+ /* Enable the Cavium RNG as a VF */
+ iov_err = pci_enable_sriov(pdev, 1);
+ if (iov_err != 0) {
+ dev_err(&pdev->dev,
+ "Error initializing RNG virtual function,(%i).\n",
+ iov_err);
+ return iov_err;
+ }
+
+ return 0;
+}
+
+/* Disable VF and RNG Hardware */
+void cavium_rng_remove(struct pci_dev *pdev)
+{
+ struct cavium_rng_pf *rng;
+
+ rng = pci_get_drvdata(pdev);
+
+ /* Remove the VF */
+ pci_disable_sriov(pdev);
+
+ /* Disable the RNG hardware and entropy source */
+ writeq(0, rng->control_status);
+}
+
+static const struct pci_device_id cavium_rng_pf_id_table[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa018), 0, 0, 0}, /* Thunder RNM */
+ {0,},
+};
+
+MODULE_DEVICE_TABLE(pci, cavium_rng_pf_id_table);
+
+static struct pci_driver cavium_rng_pf_driver = {
+ .name = "cavium_rng_pf",
+ .id_table = cavium_rng_pf_id_table,
+ .probe = cavium_rng_probe,
+ .remove = cavium_rng_remove,
+};
+
+module_pci_driver(cavium_rng_pf_driver);
+MODULE_AUTHOR("Omer Khaliq");
+MODULE_LICENSE("GPL");
--
1.9.1
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