From cc2f1908c6b8f6257b7da9124ce6d859c13cba3b Mon Sep 17 00:00:00 2001 From: Omer Khaliq Date: Tue, 23 Aug 2016 16:27:15 -0700 Subject: [PATCH] hwrng: cavium - Add Cavium HWRNG driver for ThunderX SoC. The Cavium ThunderX SoC has a hardware random number generator. This driver provides support using the HWRNG framework. Signed-off-by: Omer Khaliq Signed-off-by: Ananth Jasty Acked-by: David Daney Signed-off-by: Herbert Xu --- drivers/char/hw_random/Kconfig | 13 +++++ drivers/char/hw_random/Makefile | 1 + drivers/char/hw_random/cavium-rng-vf.c | 99 ++++++++++++++++++++++++++++++++++ drivers/char/hw_random/cavium-rng.c | 94 ++++++++++++++++++++++++++++++++ 4 files changed, 207 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..066ae0e --- /dev/null +++ b/drivers/char/hw_random/cavium-rng-vf.c @@ -0,0 +1,99 @@ +/* + * 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 +#include +#include +#include +#include + +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..a944e0a --- /dev/null +++ b/drivers/char/hw_random/cavium-rng.c @@ -0,0 +1,94 @@ +/* + * 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 +#include +#include +#include +#include + +#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); + + /* Enable the Cavium RNG as a VF */ + iov_err = pci_enable_sriov(pdev, 1); + if (iov_err != 0) { + /* Disable the RNG hardware and entropy source */ + writeq(0, rng->control_status); + 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"); -- 2.7.4