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authorLinus Torvalds <torvalds@linux-foundation.org>2017-09-06 15:17:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-09-06 15:17:17 -0700
commit80cee03bf1d626db0278271b505d7f5febb37bba (patch)
tree6fc86272106f526a9d07343c524612aa493539e6 /drivers/char
parentaae3dbb4776e7916b6cd442d00159bea27a695c1 (diff)
parent2d45a7e89833f88b38112292ff227af437f81f2f (diff)
downloadlinux-80cee03bf1d626db0278271b505d7f5febb37bba.tar.bz2
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "Here is the crypto update for 4.14: API: - Defer scompress scratch buffer allocation to first use. - Add __crypto_xor that takes separte src and dst operands. - Add ahash multiple registration interface. - Revamped aead/skcipher algif code to fix async IO properly. Drivers: - Add non-SIMD fallback code path on ARM for SVE. - Add AMD Security Processor framework for ccp. - Add support for RSA in ccp. - Add XTS-AES-256 support for CCP version 5. - Add support for PRNG in sun4i-ss. - Add support for DPAA2 in caam. - Add ARTPEC crypto support. - Add Freescale RNGC hwrng support. - Add Microchip / Atmel ECC driver. - Add support for STM32 HASH module" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (116 commits) crypto: af_alg - get_page upon reassignment to TX SGL crypto: cavium/nitrox - Fix an error handling path in 'nitrox_probe()' crypto: inside-secure - fix an error handling path in safexcel_probe() crypto: rockchip - Don't dequeue the request when device is busy crypto: cavium - add release_firmware to all return case crypto: sahara - constify platform_device_id MAINTAINERS: Add ARTPEC crypto maintainer crypto: axis - add ARTPEC-6/7 crypto accelerator driver crypto: hash - add crypto_(un)register_ahashes() dt-bindings: crypto: add ARTPEC crypto crypto: algif_aead - fix comment regarding memory layout crypto: ccp - use dma_mapping_error to check map error lib/mpi: fix build with clang crypto: sahara - Remove leftover from previous used spinlock crypto: sahara - Fix dma unmap direction crypto: af_alg - consolidation of duplicate code crypto: caam - Remove unused dentry members crypto: ccp - select CONFIG_CRYPTO_RSA crypto: ccp - avoid uninitialized variable warning crypto: serpent - improve __serpent_setkey with UBSAN ...
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/hw_random/Kconfig20
-rw-r--r--drivers/char/hw_random/Makefile1
-rw-r--r--drivers/char/hw_random/core.c42
-rw-r--r--drivers/char/hw_random/imx-rngc.c331
4 files changed, 384 insertions, 10 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 1b223c32a8ae..95a031e9eced 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -13,10 +13,8 @@ menuconfig HW_RANDOM
that's usually called /dev/hwrng, and which exposes one
of possibly several hardware random number generators.
- These hardware random number generators do not feed directly
- into the kernel's random number generator. That is usually
- handled by the "rngd" daemon. Documentation/hw_random.txt
- has more information.
+ These hardware random number generators do feed into the
+ kernel's random number generator entropy pool.
If unsure, say Y.
@@ -255,6 +253,20 @@ config HW_RANDOM_MXC_RNGA
If unsure, say Y.
+config HW_RANDOM_IMX_RNGC
+ tristate "Freescale i.MX RNGC Random Number Generator"
+ depends on ARCH_MXC
+ default HW_RANDOM
+ ---help---
+ This driver provides kernel-side support for the Random Number
+ Generator Version C hardware found on some Freescale i.MX
+ processors. Version B is also supported by this driver.
+
+ To compile this driver as a module, choose M here: the
+ module will be called imx-rngc.
+
+ If unsure, say Y.
+
config HW_RANDOM_NOMADIK
tristate "ST-Ericsson Nomadik Random Number Generator support"
depends on ARCH_NOMADIK
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index b085975ec1d2..39a67defac67 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_HW_RANDOM_PASEMI) += pasemi-rng.o
obj-$(CONFIG_HW_RANDOM_VIRTIO) += virtio-rng.o
obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o
obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o
+obj-$(CONFIG_HW_RANDOM_IMX_RNGC) += imx-rngc.o
obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o
obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index 503a41dfa193..9701ac7d8b47 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -28,7 +28,10 @@
#define RNG_MODULE_NAME "hw_random"
static struct hwrng *current_rng;
+/* the current rng has been explicitly chosen by user via sysfs */
+static int cur_rng_set_by_user;
static struct task_struct *hwrng_fill;
+/* list of registered rngs, sorted decending by quality */
static LIST_HEAD(rng_list);
/* Protects rng_list and current_rng */
static DEFINE_MUTEX(rng_mutex);
@@ -303,6 +306,7 @@ static ssize_t hwrng_attr_current_store(struct device *dev,
list_for_each_entry(rng, &rng_list, list) {
if (sysfs_streq(rng->name, buf)) {
err = 0;
+ cur_rng_set_by_user = 1;
if (rng != current_rng)
err = set_current_rng(rng);
break;
@@ -351,16 +355,27 @@ static ssize_t hwrng_attr_available_show(struct device *dev,
return strlen(buf);
}
+static ssize_t hwrng_attr_selected_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n", cur_rng_set_by_user);
+}
+
static DEVICE_ATTR(rng_current, S_IRUGO | S_IWUSR,
hwrng_attr_current_show,
hwrng_attr_current_store);
static DEVICE_ATTR(rng_available, S_IRUGO,
hwrng_attr_available_show,
NULL);
+static DEVICE_ATTR(rng_selected, S_IRUGO,
+ hwrng_attr_selected_show,
+ NULL);
static struct attribute *rng_dev_attrs[] = {
&dev_attr_rng_current.attr,
&dev_attr_rng_available.attr,
+ &dev_attr_rng_selected.attr,
NULL
};
@@ -417,6 +432,7 @@ int hwrng_register(struct hwrng *rng)
{
int err = -EINVAL;
struct hwrng *old_rng, *tmp;
+ struct list_head *rng_list_ptr;
if (!rng->name || (!rng->data_read && !rng->read))
goto out;
@@ -432,14 +448,27 @@ int hwrng_register(struct hwrng *rng)
init_completion(&rng->cleanup_done);
complete(&rng->cleanup_done);
+ /* rng_list is sorted by decreasing quality */
+ list_for_each(rng_list_ptr, &rng_list) {
+ tmp = list_entry(rng_list_ptr, struct hwrng, list);
+ if (tmp->quality < rng->quality)
+ break;
+ }
+ list_add_tail(&rng->list, rng_list_ptr);
+
old_rng = current_rng;
err = 0;
- if (!old_rng) {
+ if (!old_rng ||
+ (!cur_rng_set_by_user && rng->quality > old_rng->quality)) {
+ /*
+ * Set new rng as current as the new rng source
+ * provides better entropy quality and was not
+ * chosen by userspace.
+ */
err = set_current_rng(rng);
if (err)
goto out_unlock;
}
- list_add_tail(&rng->list, &rng_list);
if (old_rng && !rng->init) {
/*
@@ -466,12 +495,13 @@ void hwrng_unregister(struct hwrng *rng)
list_del(&rng->list);
if (current_rng == rng) {
drop_current_rng();
+ cur_rng_set_by_user = 0;
+ /* rng_list is sorted by quality, use the best (=first) one */
if (!list_empty(&rng_list)) {
- struct hwrng *tail;
-
- tail = list_entry(rng_list.prev, struct hwrng, list);
+ struct hwrng *new_rng;
- set_current_rng(tail);
+ new_rng = list_entry(rng_list.next, struct hwrng, list);
+ set_current_rng(new_rng);
}
}
diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
new file mode 100644
index 000000000000..88db42d30760
--- /dev/null
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -0,0 +1,331 @@
+/*
+ * RNG driver for Freescale RNGC
+ *
+ * Copyright (C) 2008-2012 Freescale Semiconductor, Inc.
+ * Copyright (C) 2017 Martin Kaiser <martin@kaiser.cx>
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/hw_random.h>
+#include <linux/completion.h>
+#include <linux/io.h>
+
+#define RNGC_COMMAND 0x0004
+#define RNGC_CONTROL 0x0008
+#define RNGC_STATUS 0x000C
+#define RNGC_ERROR 0x0010
+#define RNGC_FIFO 0x0014
+
+#define RNGC_CMD_CLR_ERR 0x00000020
+#define RNGC_CMD_CLR_INT 0x00000010
+#define RNGC_CMD_SEED 0x00000002
+#define RNGC_CMD_SELF_TEST 0x00000001
+
+#define RNGC_CTRL_MASK_ERROR 0x00000040
+#define RNGC_CTRL_MASK_DONE 0x00000020
+
+#define RNGC_STATUS_ERROR 0x00010000
+#define RNGC_STATUS_FIFO_LEVEL_MASK 0x00000f00
+#define RNGC_STATUS_FIFO_LEVEL_SHIFT 8
+#define RNGC_STATUS_SEED_DONE 0x00000020
+#define RNGC_STATUS_ST_DONE 0x00000010
+
+#define RNGC_ERROR_STATUS_STAT_ERR 0x00000008
+
+#define RNGC_TIMEOUT 3000 /* 3 sec */
+
+
+static bool self_test = true;
+module_param(self_test, bool, 0);
+
+struct imx_rngc {
+ struct device *dev;
+ struct clk *clk;
+ void __iomem *base;
+ struct hwrng rng;
+ struct completion rng_op_done;
+ /*
+ * err_reg is written only by the irq handler and read only
+ * when interrupts are masked, we need no spinlock
+ */
+ u32 err_reg;
+};
+
+
+static inline void imx_rngc_irq_mask_clear(struct imx_rngc *rngc)
+{
+ u32 ctrl, cmd;
+
+ /* mask interrupts */
+ ctrl = readl(rngc->base + RNGC_CONTROL);
+ ctrl |= RNGC_CTRL_MASK_DONE | RNGC_CTRL_MASK_ERROR;
+ writel(ctrl, rngc->base + RNGC_CONTROL);
+
+ /*
+ * CLR_INT clears the interrupt only if there's no error
+ * CLR_ERR clear the interrupt and the error register if there
+ * is an error
+ */
+ cmd = readl(rngc->base + RNGC_COMMAND);
+ cmd |= RNGC_CMD_CLR_INT | RNGC_CMD_CLR_ERR;
+ writel(cmd, rngc->base + RNGC_COMMAND);
+}
+
+static inline void imx_rngc_irq_unmask(struct imx_rngc *rngc)
+{
+ u32 ctrl;
+
+ ctrl = readl(rngc->base + RNGC_CONTROL);
+ ctrl &= ~(RNGC_CTRL_MASK_DONE | RNGC_CTRL_MASK_ERROR);
+ writel(ctrl, rngc->base + RNGC_CONTROL);
+}
+
+static int imx_rngc_self_test(struct imx_rngc *rngc)
+{
+ u32 cmd;
+ int ret;
+
+ imx_rngc_irq_unmask(rngc);
+
+ /* run self test */
+ cmd = readl(rngc->base + RNGC_COMMAND);
+ writel(cmd | RNGC_CMD_SELF_TEST, rngc->base + RNGC_COMMAND);
+
+ ret = wait_for_completion_timeout(&rngc->rng_op_done, RNGC_TIMEOUT);
+ if (!ret) {
+ imx_rngc_irq_mask_clear(rngc);
+ return -ETIMEDOUT;
+ }
+
+ if (rngc->err_reg != 0)
+ return -EIO;
+
+ return 0;
+}
+
+static int imx_rngc_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+ struct imx_rngc *rngc = container_of(rng, struct imx_rngc, rng);
+ unsigned int status;
+ unsigned int level;
+ int retval = 0;
+
+ while (max >= sizeof(u32)) {
+ status = readl(rngc->base + RNGC_STATUS);
+
+ /* is there some error while reading this random number? */
+ if (status & RNGC_STATUS_ERROR)
+ break;
+
+ /* how many random numbers are in FIFO? [0-16] */
+ level = (status & RNGC_STATUS_FIFO_LEVEL_MASK) >>
+ RNGC_STATUS_FIFO_LEVEL_SHIFT;
+
+ if (level) {
+ /* retrieve a random number from FIFO */
+ *(u32 *)data = readl(rngc->base + RNGC_FIFO);
+
+ retval += sizeof(u32);
+ data += sizeof(u32);
+ max -= sizeof(u32);
+ }
+ }
+
+ return retval ? retval : -EIO;
+}
+
+static irqreturn_t imx_rngc_irq(int irq, void *priv)
+{
+ struct imx_rngc *rngc = (struct imx_rngc *)priv;
+ u32 status;
+
+ /*
+ * clearing the interrupt will also clear the error register
+ * read error and status before clearing
+ */
+ status = readl(rngc->base + RNGC_STATUS);
+ rngc->err_reg = readl(rngc->base + RNGC_ERROR);
+
+ imx_rngc_irq_mask_clear(rngc);
+
+ if (status & (RNGC_STATUS_SEED_DONE | RNGC_STATUS_ST_DONE))
+ complete(&rngc->rng_op_done);
+
+ return IRQ_HANDLED;
+}
+
+static int imx_rngc_init(struct hwrng *rng)
+{
+ struct imx_rngc *rngc = container_of(rng, struct imx_rngc, rng);
+ u32 cmd;
+ int ret;
+
+ /* clear error */
+ cmd = readl(rngc->base + RNGC_COMMAND);
+ writel(cmd | RNGC_CMD_CLR_ERR, rngc->base + RNGC_COMMAND);
+
+ /* create seed, repeat while there is some statistical error */
+ do {
+ imx_rngc_irq_unmask(rngc);
+
+ /* seed creation */
+ cmd = readl(rngc->base + RNGC_COMMAND);
+ writel(cmd | RNGC_CMD_SEED, rngc->base + RNGC_COMMAND);
+
+ ret = wait_for_completion_timeout(&rngc->rng_op_done,
+ RNGC_TIMEOUT);
+
+ if (!ret) {
+ imx_rngc_irq_mask_clear(rngc);
+ return -ETIMEDOUT;
+ }
+
+ } while (rngc->err_reg == RNGC_ERROR_STATUS_STAT_ERR);
+
+ return rngc->err_reg ? -EIO : 0;
+}
+
+static int imx_rngc_probe(struct platform_device *pdev)
+{
+ struct imx_rngc *rngc;
+ struct resource *res;
+ int ret;
+ int irq;
+
+ rngc = devm_kzalloc(&pdev->dev, sizeof(*rngc), GFP_KERNEL);
+ if (!rngc)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rngc->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(rngc->base))
+ return PTR_ERR(rngc->base);
+
+ rngc->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(rngc->clk)) {
+ dev_err(&pdev->dev, "Can not get rng_clk\n");
+ return PTR_ERR(rngc->clk);
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0) {
+ dev_err(&pdev->dev, "Couldn't get irq %d\n", irq);
+ return irq;
+ }
+
+ ret = clk_prepare_enable(rngc->clk);
+ if (ret)
+ return ret;
+
+ ret = devm_request_irq(&pdev->dev,
+ irq, imx_rngc_irq, 0, pdev->name, (void *)rngc);
+ if (ret) {
+ dev_err(rngc->dev, "Can't get interrupt working.\n");
+ goto err;
+ }
+
+ init_completion(&rngc->rng_op_done);
+
+ rngc->rng.name = pdev->name;
+ rngc->rng.init = imx_rngc_init;
+ rngc->rng.read = imx_rngc_read;
+
+ rngc->dev = &pdev->dev;
+ platform_set_drvdata(pdev, rngc);
+
+ imx_rngc_irq_mask_clear(rngc);
+
+ if (self_test) {
+ ret = imx_rngc_self_test(rngc);
+ if (ret) {
+ dev_err(rngc->dev, "FSL RNGC self test failed.\n");
+ goto err;
+ }
+ }
+
+ ret = hwrng_register(&rngc->rng);
+ if (ret) {
+ dev_err(&pdev->dev, "FSL RNGC registering failed (%d)\n", ret);
+ goto err;
+ }
+
+ dev_info(&pdev->dev, "Freescale RNGC registered.\n");
+ return 0;
+
+err:
+ clk_disable_unprepare(rngc->clk);
+
+ return ret;
+}
+
+static int __exit imx_rngc_remove(struct platform_device *pdev)
+{
+ struct imx_rngc *rngc = platform_get_drvdata(pdev);
+
+ hwrng_unregister(&rngc->rng);
+
+ clk_disable_unprepare(rngc->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int imx_rngc_suspend(struct device *dev)
+{
+ struct imx_rngc *rngc = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(rngc->clk);
+
+ return 0;
+}
+
+static int imx_rngc_resume(struct device *dev)
+{
+ struct imx_rngc *rngc = dev_get_drvdata(dev);
+
+ clk_prepare_enable(rngc->clk);
+
+ return 0;
+}
+
+static const struct dev_pm_ops imx_rngc_pm_ops = {
+ .suspend = imx_rngc_suspend,
+ .resume = imx_rngc_resume,
+};
+#endif
+
+static const struct of_device_id imx_rngc_dt_ids[] = {
+ { .compatible = "fsl,imx25-rngb", .data = NULL, },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_rngc_dt_ids);
+
+static struct platform_driver imx_rngc_driver = {
+ .driver = {
+ .name = "imx_rngc",
+#ifdef CONFIG_PM
+ .pm = &imx_rngc_pm_ops,
+#endif
+ .of_match_table = imx_rngc_dt_ids,
+ },
+ .remove = __exit_p(imx_rngc_remove),
+};
+
+module_platform_driver_probe(imx_rngc_driver, imx_rngc_probe);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("H/W RNGC driver for i.MX");
+MODULE_LICENSE("GPL");