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-rw-r--r--drivers/char/hw_random/Kconfig13
-rw-r--r--drivers/char/hw_random/Makefile1
-rw-r--r--drivers/char/hw_random/cavium-rng-vf.c194
-rw-r--r--drivers/char/hw_random/cavium-rng.c11
-rw-r--r--drivers/char/hw_random/cn10k-rng.c181
5 files changed, 383 insertions, 17 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 814b3d0ca7b7..001b819f5298 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -414,7 +414,7 @@ config HW_RANDOM_MESON
config HW_RANDOM_CAVIUM
tristate "Cavium ThunderX Random Number Generator support"
- depends on HW_RANDOM && PCI && (ARM64 || (COMPILE_TEST && 64BIT))
+ depends on HW_RANDOM && PCI && ARM64
default HW_RANDOM
help
This driver provides kernel-side support for the Random Number
@@ -538,6 +538,17 @@ config HW_RANDOM_ARM_SMCCC_TRNG
To compile this driver as a module, choose M here: the
module will be called arm_smccc_trng.
+config HW_RANDOM_CN10K
+ tristate "Marvell CN10K Random Number Generator support"
+ depends on HW_RANDOM && PCI && ARM64
+ default HW_RANDOM
+ help
+ This driver provides support for the True Random Number
+ generator available in Marvell CN10K SoCs.
+
+ To compile this driver as a module, choose M here.
+ The module will be called cn10k_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 a5a1c765a394..a2f1ce0790d1 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -46,3 +46,4 @@ obj-$(CONFIG_HW_RANDOM_NPCM) += npcm-rng.o
obj-$(CONFIG_HW_RANDOM_CCTRNG) += cctrng.o
obj-$(CONFIG_HW_RANDOM_XIPHERA) += xiphera-trng.o
obj-$(CONFIG_HW_RANDOM_ARM_SMCCC_TRNG) += arm_smccc_trng.o
+obj-$(CONFIG_HW_RANDOM_CN10K) += cn10k-rng.o
diff --git a/drivers/char/hw_random/cavium-rng-vf.c b/drivers/char/hw_random/cavium-rng-vf.c
index 3de4a6a443ef..6f66919652bf 100644
--- a/drivers/char/hw_random/cavium-rng-vf.c
+++ b/drivers/char/hw_random/cavium-rng-vf.c
@@ -1,10 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
/*
- * 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.
+ * Hardware Random Number Generator support.
+ * Cavium Thunder, Marvell OcteonTx/Tx2 processor families.
*
* Copyright (C) 2016 Cavium, Inc.
*/
@@ -15,16 +12,146 @@
#include <linux/pci.h>
#include <linux/pci_ids.h>
+#include <asm/arch_timer.h>
+
+/* PCI device IDs */
+#define PCI_DEVID_CAVIUM_RNG_PF 0xA018
+#define PCI_DEVID_CAVIUM_RNG_VF 0xA033
+
+#define HEALTH_STATUS_REG 0x38
+
+/* RST device info */
+#define PCI_DEVICE_ID_RST_OTX2 0xA085
+#define RST_BOOT_REG 0x1600ULL
+#define CLOCK_BASE_RATE 50000000ULL
+#define MSEC_TO_NSEC(x) (x * 1000000)
+
struct cavium_rng {
struct hwrng ops;
void __iomem *result;
+ void __iomem *pf_regbase;
+ struct pci_dev *pdev;
+ u64 clock_rate;
+ u64 prev_error;
+ u64 prev_time;
};
+static inline bool is_octeontx(struct pci_dev *pdev)
+{
+ if (midr_is_cpu_model_range(read_cpuid_id(), MIDR_THUNDERX_83XX,
+ MIDR_CPU_VAR_REV(0, 0),
+ MIDR_CPU_VAR_REV(3, 0)) ||
+ midr_is_cpu_model_range(read_cpuid_id(), MIDR_THUNDERX_81XX,
+ MIDR_CPU_VAR_REV(0, 0),
+ MIDR_CPU_VAR_REV(3, 0)) ||
+ midr_is_cpu_model_range(read_cpuid_id(), MIDR_THUNDERX,
+ MIDR_CPU_VAR_REV(0, 0),
+ MIDR_CPU_VAR_REV(3, 0)))
+ return true;
+
+ return false;
+}
+
+static u64 rng_get_coprocessor_clkrate(void)
+{
+ u64 ret = CLOCK_BASE_RATE * 16; /* Assume 800Mhz as default */
+ struct pci_dev *pdev;
+ void __iomem *base;
+
+ pdev = pci_get_device(PCI_VENDOR_ID_CAVIUM,
+ PCI_DEVICE_ID_RST_OTX2, NULL);
+ if (!pdev)
+ goto error;
+
+ base = pci_ioremap_bar(pdev, 0);
+ if (!base)
+ goto error_put_pdev;
+
+ /* RST: PNR_MUL * 50Mhz gives clockrate */
+ ret = CLOCK_BASE_RATE * ((readq(base + RST_BOOT_REG) >> 33) & 0x3F);
+
+ iounmap(base);
+
+error_put_pdev:
+ pci_dev_put(pdev);
+
+error:
+ return ret;
+}
+
+static int check_rng_health(struct cavium_rng *rng)
+{
+ u64 cur_err, cur_time;
+ u64 status, cycles;
+ u64 time_elapsed;
+
+
+ /* Skip checking health for OcteonTx */
+ if (!rng->pf_regbase)
+ return 0;
+
+ status = readq(rng->pf_regbase + HEALTH_STATUS_REG);
+ if (status & BIT_ULL(0)) {
+ dev_err(&rng->pdev->dev, "HWRNG: Startup health test failed\n");
+ return -EIO;
+ }
+
+ cycles = status >> 1;
+ if (!cycles)
+ return 0;
+
+ cur_time = arch_timer_read_counter();
+
+ /* RNM_HEALTH_STATUS[CYCLES_SINCE_HEALTH_FAILURE]
+ * Number of coprocessor cycles times 2 since the last failure.
+ * This field doesn't get cleared/updated until another failure.
+ */
+ cycles = cycles / 2;
+ cur_err = (cycles * 1000000000) / rng->clock_rate; /* In nanosec */
+
+ /* Ignore errors that happenned a long time ago, these
+ * are most likely false positive errors.
+ */
+ if (cur_err > MSEC_TO_NSEC(10)) {
+ rng->prev_error = 0;
+ rng->prev_time = 0;
+ return 0;
+ }
+
+ if (rng->prev_error) {
+ /* Calculate time elapsed since last error
+ * '1' tick of CNTVCT is 10ns, since it runs at 100Mhz.
+ */
+ time_elapsed = (cur_time - rng->prev_time) * 10;
+ time_elapsed += rng->prev_error;
+
+ /* Check if current error is a new one or the old one itself.
+ * If error is a new one then consider there is a persistent
+ * issue with entropy, declare hardware failure.
+ */
+ if (cur_err < time_elapsed) {
+ dev_err(&rng->pdev->dev, "HWRNG failure detected\n");
+ rng->prev_error = cur_err;
+ rng->prev_time = cur_time;
+ return -EIO;
+ }
+ }
+
+ rng->prev_error = cur_err;
+ rng->prev_time = cur_time;
+ return 0;
+}
+
/* 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;
+ int err = 0;
+
+ err = check_rng_health(p);
+ if (err)
+ return err;
while (size >= 8) {
*((u64 *)dat) = readq(p->result);
@@ -39,6 +166,39 @@ static int cavium_rng_read(struct hwrng *rng, void *dat, size_t max, bool wait)
return max;
}
+static int cavium_map_pf_regs(struct cavium_rng *rng)
+{
+ struct pci_dev *pdev;
+
+ /* Health status is not supported on 83xx, skip mapping PF CSRs */
+ if (is_octeontx(rng->pdev)) {
+ rng->pf_regbase = NULL;
+ return 0;
+ }
+
+ pdev = pci_get_device(PCI_VENDOR_ID_CAVIUM,
+ PCI_DEVID_CAVIUM_RNG_PF, NULL);
+ if (!pdev) {
+ dev_err(&pdev->dev, "Cannot find RNG PF device\n");
+ return -EIO;
+ }
+
+ rng->pf_regbase = ioremap(pci_resource_start(pdev, 0),
+ pci_resource_len(pdev, 0));
+ if (!rng->pf_regbase) {
+ dev_err(&pdev->dev, "Failed to map PF CSR region\n");
+ pci_dev_put(pdev);
+ return -ENOMEM;
+ }
+
+ pci_dev_put(pdev);
+
+ /* Get co-processor clock rate */
+ rng->clock_rate = rng_get_coprocessor_clkrate();
+
+ return 0;
+}
+
/* Map Cavium RNG to an HWRNG object */
static int cavium_rng_probe_vf(struct pci_dev *pdev,
const struct pci_device_id *id)
@@ -50,6 +210,8 @@ static int cavium_rng_probe_vf(struct pci_dev *pdev,
if (!rng)
return -ENOMEM;
+ rng->pdev = pdev;
+
/* Map the RNG result */
rng->result = pcim_iomap(pdev, 0, 0);
if (!rng->result) {
@@ -67,6 +229,11 @@ static int cavium_rng_probe_vf(struct pci_dev *pdev,
pci_set_drvdata(pdev, rng);
+ /* Health status is available only at PF, hence map PF registers. */
+ ret = cavium_map_pf_regs(rng);
+ if (ret)
+ return ret;
+
ret = devm_hwrng_register(&pdev->dev, &rng->ops);
if (ret) {
dev_err(&pdev->dev, "Error registering device as HWRNG.\n");
@@ -76,10 +243,18 @@ static int cavium_rng_probe_vf(struct pci_dev *pdev,
return 0;
}
+/* Remove the VF */
+static void cavium_rng_remove_vf(struct pci_dev *pdev)
+{
+ struct cavium_rng *rng;
+
+ rng = pci_get_drvdata(pdev);
+ iounmap(rng->pf_regbase);
+}
static const struct pci_device_id cavium_rng_vf_id_table[] = {
- { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa033), 0, 0, 0},
- {0,},
+ { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVID_CAVIUM_RNG_VF) },
+ { 0, }
};
MODULE_DEVICE_TABLE(pci, cavium_rng_vf_id_table);
@@ -87,8 +262,9 @@ 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 <okhaliq@caviumnetworks.com>");
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/char/hw_random/cavium-rng.c b/drivers/char/hw_random/cavium-rng.c
index 63d6e68c24d2..b96579222408 100644
--- a/drivers/char/hw_random/cavium-rng.c
+++ b/drivers/char/hw_random/cavium-rng.c
@@ -1,10 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
/*
- * 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.
+ * Hardware Random Number Generator support.
+ * Cavium Thunder, Marvell OcteonTx/Tx2 processor families.
*
* Copyright (C) 2016 Cavium, Inc.
*/
@@ -91,4 +88,4 @@ static struct pci_driver cavium_rng_pf_driver = {
module_pci_driver(cavium_rng_pf_driver);
MODULE_AUTHOR("Omer Khaliq <okhaliq@caviumnetworks.com>");
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/char/hw_random/cn10k-rng.c b/drivers/char/hw_random/cn10k-rng.c
new file mode 100644
index 000000000000..35001c63648b
--- /dev/null
+++ b/drivers/char/hw_random/cn10k-rng.c
@@ -0,0 +1,181 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Marvell CN10K RVU Hardware Random Number Generator.
+ *
+ * Copyright (C) 2021 Marvell.
+ *
+ */
+
+#include <linux/hw_random.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/delay.h>
+
+#include <linux/arm-smccc.h>
+
+/* CSRs */
+#define RNM_CTL_STATUS 0x000
+#define RNM_ENTROPY_STATUS 0x008
+#define RNM_CONST 0x030
+#define RNM_EBG_ENT 0x048
+#define RNM_PF_EBG_HEALTH 0x050
+#define RNM_PF_RANDOM 0x400
+#define RNM_TRNG_RESULT 0x408
+
+struct cn10k_rng {
+ void __iomem *reg_base;
+ struct hwrng ops;
+ struct pci_dev *pdev;
+};
+
+#define PLAT_OCTEONTX_RESET_RNG_EBG_HEALTH_STATE 0xc2000b0f
+
+static int reset_rng_health_state(struct cn10k_rng *rng)
+{
+ struct arm_smccc_res res;
+
+ /* Send SMC service call to reset EBG health state */
+ arm_smccc_smc(PLAT_OCTEONTX_RESET_RNG_EBG_HEALTH_STATE, 0, 0, 0, 0, 0, 0, 0, &res);
+ if (res.a0 != 0UL)
+ return -EIO;
+
+ return 0;
+}
+
+static int check_rng_health(struct cn10k_rng *rng)
+{
+ u64 status;
+ int err;
+
+ /* Skip checking health */
+ if (!rng->reg_base)
+ return 0;
+
+ status = readq(rng->reg_base + RNM_PF_EBG_HEALTH);
+ if (status & BIT_ULL(20)) {
+ err = reset_rng_health_state(rng);
+ if (err) {
+ dev_err(&rng->pdev->dev, "HWRNG: Health test failed (status=%llx)\n",
+ status);
+ dev_err(&rng->pdev->dev, "HWRNG: error during reset\n");
+ }
+ }
+ return 0;
+}
+
+static void cn10k_read_trng(struct cn10k_rng *rng, u64 *value)
+{
+ u64 upper, lower;
+
+ *value = readq(rng->reg_base + RNM_PF_RANDOM);
+
+ /* HW can run out of entropy if large amount random data is read in
+ * quick succession. Zeros may not be real random data from HW.
+ */
+ if (!*value) {
+ upper = readq(rng->reg_base + RNM_PF_RANDOM);
+ lower = readq(rng->reg_base + RNM_PF_RANDOM);
+ while (!(upper & 0x00000000FFFFFFFFULL))
+ upper = readq(rng->reg_base + RNM_PF_RANDOM);
+ while (!(lower & 0xFFFFFFFF00000000ULL))
+ lower = readq(rng->reg_base + RNM_PF_RANDOM);
+
+ *value = (upper & 0xFFFFFFFF00000000) | (lower & 0xFFFFFFFF);
+ }
+}
+
+static int cn10k_rng_read(struct hwrng *hwrng, void *data,
+ size_t max, bool wait)
+{
+ struct cn10k_rng *rng = (struct cn10k_rng *)hwrng->priv;
+ unsigned int size;
+ int err = 0;
+ u64 value;
+
+ err = check_rng_health(rng);
+ if (err)
+ return err;
+
+ size = max;
+
+ while (size >= 8) {
+ cn10k_read_trng(rng, &value);
+
+ *((u64 *)data) = (u64)value;
+ size -= 8;
+ data += 8;
+ }
+
+ while (size > 0) {
+ cn10k_read_trng(rng, &value);
+
+ *((u8 *)data) = (u8)value;
+ size--;
+ data++;
+ }
+
+ return max - size;
+}
+
+static int cn10k_rng_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct cn10k_rng *rng;
+ int err;
+
+ rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
+ if (!rng)
+ return -ENOMEM;
+
+ rng->pdev = pdev;
+ pci_set_drvdata(pdev, rng);
+
+ rng->reg_base = pcim_iomap(pdev, 0, 0);
+ if (!rng->reg_base) {
+ dev_err(&pdev->dev, "Error while mapping CSRs, exiting\n");
+ return -ENOMEM;
+ }
+
+ rng->ops.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
+ "cn10k-rng-%s", dev_name(&pdev->dev));
+ if (!rng->ops.name)
+ return -ENOMEM;
+
+ rng->ops.read = cn10k_rng_read;
+ rng->ops.quality = 1000;
+ rng->ops.priv = (unsigned long)rng;
+
+ reset_rng_health_state(rng);
+
+ err = devm_hwrng_register(&pdev->dev, &rng->ops);
+ if (err) {
+ dev_err(&pdev->dev, "Could not register hwrng device.\n");
+ return err;
+ }
+
+ return 0;
+}
+
+static void cn10k_rng_remove(struct pci_dev *pdev)
+{
+ /* Nothing to do */
+}
+
+static const struct pci_device_id cn10k_rng_id_table[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xA098) }, /* RNG PF */
+ {0,},
+};
+
+MODULE_DEVICE_TABLE(pci, cn10k_rng_id_table);
+
+static struct pci_driver cn10k_rng_driver = {
+ .name = "cn10k_rng",
+ .id_table = cn10k_rng_id_table,
+ .probe = cn10k_rng_probe,
+ .remove = cn10k_rng_remove,
+};
+
+module_pci_driver(cn10k_rng_driver);
+MODULE_AUTHOR("Sunil Goutham <sgoutham@marvell.com>");
+MODULE_DESCRIPTION("Marvell CN10K HW RNG Driver");
+MODULE_LICENSE("GPL v2");
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.