9 files changed, 216 insertions, 99 deletions

diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index 87060266ef91..d31483c54883 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -114,7 +114,7 @@ config HW_RANDOM_IXP4XX
 
 config HW_RANDOM_OMAP
         tristate "OMAP Random Number Generator support"
-        depends on HW_RANDOM && (ARCH_OMAP16XX || ARCH_OMAP24XX)
+        depends on HW_RANDOM && (ARCH_OMAP16XX || ARCH_OMAP2)
         default HW_RANDOM
         ---help---
           This driver provides kernel-side support for the Random Number
@@ -186,3 +186,15 @@ config HW_RANDOM_MXC_RNGA
           module will be called mxc-rnga.
 
           If unsure, say Y.
+
+config HW_RANDOM_NOMADIK
+        tristate "ST-Ericsson Nomadik Random Number Generator support"
+        depends on HW_RANDOM && PLAT_NOMADIK
+        ---help---
+          This driver provides kernel-side support for the Random Number
+          Generator hardware found on ST-Ericsson SoCs (8815 and 8500).
+
+          To compile this driver as a module, choose M here: the
+          module will be called nomadik-rng.
+
+          If unsure, say Y.
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 5eeb1303f0d0..4273308aa1e3 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -18,3 +18,4 @@ 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_OCTEON) += octeon-rng.o
+obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index 1573aebd54b5..3d9c61e5acbf 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -52,7 +52,9 @@
 static struct hwrng *current_rng;
 static LIST_HEAD(rng_list);
 static DEFINE_MUTEX(rng_mutex);
-
+static int data_avail;
+static u8 rng_buffer[SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES]
+        __cacheline_aligned;
 
 static inline int hwrng_init(struct hwrng *rng)
 {
@@ -67,19 +69,6 @@ static inline void hwrng_cleanup(struct hwrng *rng)
                 rng->cleanup(rng);
 }
 
-static inline int hwrng_data_present(struct hwrng *rng, int wait)
-{
-        if (!rng->data_present)
-                return 1;
-        return rng->data_present(rng, wait);
-}
-
-static inline int hwrng_data_read(struct hwrng *rng, u32 *data)
-{
-        return rng->data_read(rng, data);
-}
-
-
 static int rng_dev_open(struct inode *inode, struct file *filp)
 {
         /* enforce read-only access to this chrdev */
@@ -87,60 +76,93 @@ static int rng_dev_open(struct inode *inode, struct file *filp)
                 return -EINVAL;
         if (filp->f_mode & FMODE_WRITE)
                 return -EINVAL;
-        cycle_kernel_lock();
+        return 0;
+}
+
+static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
+                        int wait) {
+        int present;
+
+        if (rng->read)
+                return rng->read(rng, (void *)buffer, size, wait);
+
+        if (rng->data_present)
+                present = rng->data_present(rng, wait);
+        else
+                present = 1;
+
+        if (present)
+                return rng->data_read(rng, (u32 *)buffer);
+
         return 0;
 }
 
 static ssize_t rng_dev_read(struct file *filp, char __user *buf,
                             size_t size, loff_t *offp)
 {
-        u32 data;
         ssize_t ret = 0;
         int err = 0;
-        int bytes_read;
+        int bytes_read, len;
 
         while (size) {
-                err = -ERESTARTSYS;
-                if (mutex_lock_interruptible(&rng_mutex))
+                if (mutex_lock_interruptible(&rng_mutex)) {
+                        err = -ERESTARTSYS;
                         goto out;
+                }
+
                 if (!current_rng) {
-                        mutex_unlock(&rng_mutex);
                         err = -ENODEV;
-                        goto out;
+                        goto out_unlock;
                 }
 
-                bytes_read = 0;
-                if (hwrng_data_present(current_rng,
-                                       !(filp->f_flags & O_NONBLOCK)))
-                        bytes_read = hwrng_data_read(current_rng, &data);
-                mutex_unlock(&rng_mutex);
-
-                err = -EAGAIN;
-                if (!bytes_read && (filp->f_flags & O_NONBLOCK))
-                        goto out;
-                if (bytes_read < 0) {
-                        err = bytes_read;
-                        goto out;
+                if (!data_avail) {
+                        bytes_read = rng_get_data(current_rng, rng_buffer,
+                                sizeof(rng_buffer),
+                                !(filp->f_flags & O_NONBLOCK));
+                        if (bytes_read < 0) {
+                                err = bytes_read;
+                                goto out_unlock;
+                        }
+                        data_avail = bytes_read;
                 }
 
-                err = -EFAULT;
-                while (bytes_read && size) {
-                        if (put_user((u8)data, buf++))
-                                goto out;
-                        size--;
-                        ret++;
-                        bytes_read--;
-                        data >>= 8;
+                if (!data_avail) {
+                        if (filp->f_flags & O_NONBLOCK) {
+                                err = -EAGAIN;
+                                goto out_unlock;
+                        }
+                } else {
+                        len = data_avail;
+                        if (len > size)
+                                len = size;
+
+                        data_avail -= len;
+
+                        if (copy_to_user(buf + ret, rng_buffer + data_avail,
+                                                                len)) {
+                                err = -EFAULT;
+                                goto out_unlock;
+                        }
+
+                        size -= len;
+                        ret += len;
                 }
 
+                mutex_unlock(&rng_mutex);
+
                 if (need_resched())
                         schedule_timeout_interruptible(1);
-                err = -ERESTARTSYS;
-                if (signal_pending(current))
+
+                if (signal_pending(current)) {
+                        err = -ERESTARTSYS;
                         goto out;
+                }
         }
 out:
         return ret ? : err;
+out_unlock:
+        mutex_unlock(&rng_mutex);
+        goto out;
 }
 
 
@@ -280,7 +302,7 @@ int hwrng_register(struct hwrng *rng)
         struct hwrng *old_rng, *tmp;
 
         if (rng->name == NULL ||
-            rng->data_read == NULL)
+            (rng->data_read == NULL && rng->read == NULL))
                 goto out;
 
         mutex_lock(&rng_mutex);
diff --git a/drivers/char/hw_random/intel-rng.c b/drivers/char/hw_random/intel-rng.c
index 91b53eb1c053..86fe45c19968 100644
--- a/drivers/char/hw_random/intel-rng.c
+++ b/drivers/char/hw_random/intel-rng.c
@@ -30,6 +30,7 @@
 #include <linux/pci.h>
 #include <linux/stop_machine.h>
 #include <linux/delay.h>
+#include <linux/slab.h>
 #include <asm/io.h>
 
 
diff --git a/drivers/char/hw_random/n2-drv.c b/drivers/char/hw_random/n2-drv.c
index 9b3e09cd41f9..10f868eefaa6 100644
--- a/drivers/char/hw_random/n2-drv.c
+++ b/drivers/char/hw_random/n2-drv.c
@@ -71,7 +71,7 @@ MODULE_VERSION(DRV_MODULE_VERSION);
  *        x22 + x21 + x17 + x15 + x13 + x12 + x11 + x7 + x5 + x + 1
  *
  * The RNG_CTL_VCO value of each noise cell must be programmed
- * seperately.  This is why 4 control register values must be provided
+ * separately.  This is why 4 control register values must be provided
  * to the hypervisor.  During a write, the hypervisor writes them all,
  * one at a time, to the actual RNG_CTL register.  The first three
  * values are used to setup the desired RNG_CTL_VCO for each entropy
diff --git a/drivers/char/hw_random/nomadik-rng.c b/drivers/char/hw_random/nomadik-rng.c
new file mode 100644
index 000000000000..a8b4c4010144
--- /dev/null
+++ b/drivers/char/hw_random/nomadik-rng.c
@@ -0,0 +1,103 @@
+/*
+ * Nomadik RNG support
+ *  Copyright 2009 Alessandro Rubini
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/amba/bus.h>
+#include <linux/hw_random.h>
+#include <linux/io.h>
+
+static int nmk_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+        void __iomem *base = (void __iomem *)rng->priv;
+
+        /*
+         * The register is 32 bits and gives 16 random bits (low half).
+         * A subsequent read will delay the core for 400ns, so we just read
+         * once and accept the very unlikely very small delay, even if wait==0.
+         */
+        *(u16 *)data = __raw_readl(base + 8) & 0xffff;
+        return 2;
+}
+
+/* we have at most one RNG per machine, granted */
+static struct hwrng nmk_rng = {
+        .name           = "nomadik",
+        .read           = nmk_rng_read,
+};
+
+static int nmk_rng_probe(struct amba_device *dev, struct amba_id *id)
+{
+        void __iomem *base;
+        int ret;
+
+        ret = amba_request_regions(dev, dev->dev.init_name);
+        if (ret)
+                return ret;
+        ret = -ENOMEM;
+        base = ioremap(dev->res.start, resource_size(&dev->res));
+        if (!base)
+                goto out_release;
+        nmk_rng.priv = (unsigned long)base;
+        ret = hwrng_register(&nmk_rng);
+        if (ret)
+                goto out_unmap;
+        return 0;
+
+out_unmap:
+        iounmap(base);
+out_release:
+        amba_release_regions(dev);
+        return ret;
+}
+
+static int nmk_rng_remove(struct amba_device *dev)
+{
+        void __iomem *base = (void __iomem *)nmk_rng.priv;
+        hwrng_unregister(&nmk_rng);
+        iounmap(base);
+        amba_release_regions(dev);
+        return 0;
+}
+
+static struct amba_id nmk_rng_ids[] = {
+        {
+                .id     = 0x000805e1,
+                .mask   = 0x000fffff, /* top bits are rev and cfg: accept all */
+        },
+        {0, 0},
+};
+
+static struct amba_driver nmk_rng_driver = {
+        .drv = {
+                .owner = THIS_MODULE,
+                .name = "rng",
+                },
+        .probe = nmk_rng_probe,
+        .remove = nmk_rng_remove,
+        .id_table = nmk_rng_ids,
+};
+
+static int __init nmk_rng_init(void)
+{
+        return amba_driver_register(&nmk_rng_driver);
+}
+
+static void __devexit nmk_rng_exit(void)
+{
+        amba_driver_unregister(&nmk_rng_driver);
+}
+
+module_init(nmk_rng_init);
+module_exit(nmk_rng_exit);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/char/hw_random/octeon-rng.c b/drivers/char/hw_random/octeon-rng.c
index 54b0d9ba65cf..9cd0feca318c 100644
--- a/drivers/char/hw_random/octeon-rng.c
+++ b/drivers/char/hw_random/octeon-rng.c
@@ -15,6 +15,7 @@
 #include <linux/device.h>
 #include <linux/hw_random.h>
 #include <linux/io.h>
+#include <linux/gfp.h>
 
 #include <asm/octeon/octeon.h>
 #include <asm/octeon/cvmx-rnm-defs.h>
diff --git a/drivers/char/hw_random/tx4939-rng.c b/drivers/char/hw_random/tx4939-rng.c
index 544d9085a8e8..0bc0cb70210b 100644
--- a/drivers/char/hw_random/tx4939-rng.c
+++ b/drivers/char/hw_random/tx4939-rng.c
@@ -14,6 +14,7 @@
 #include <linux/io.h>
 #include <linux/platform_device.h>
 #include <linux/hw_random.h>
+#include <linux/gfp.h>
 
 #define TX4939_RNG_RCSR         0x00000000
 #define TX4939_RNG_ROR(n)       (0x00000018 + (n) * 8)
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index 915157fcff98..64fe0a793efd 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -16,6 +16,7 @@
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  */
+
 #include <linux/err.h>
 #include <linux/hw_random.h>
 #include <linux/scatterlist.h>
@@ -23,78 +24,64 @@
 #include <linux/virtio.h>
 #include <linux/virtio_rng.h>
 
-/* The host will fill any buffer we give it with sweet, sweet randomness.  We
- * give it 64 bytes at a time, and the hwrng framework takes it 4 bytes at a
- * time. */
-#define RANDOM_DATA_SIZE 64
-
 static struct virtqueue *vq;
-static u32 *random_data;
-static unsigned int data_left;
+static unsigned int data_avail;
 static DECLARE_COMPLETION(have_data);
+static bool busy;
 
 static void random_recv_done(struct virtqueue *vq)
 {
-        unsigned int len;
-
         /* We can get spurious callbacks, e.g. shared IRQs + virtio_pci. */
-        if (!vq->vq_ops->get_buf(vq, &len))
+        if (!vq->vq_ops->get_buf(vq, &data_avail))
                 return;
 
-        data_left += len;
         complete(&have_data);
 }
 
-static void register_buffer(void)
+/* The host will fill any buffer we give it with sweet, sweet randomness. */
+static void register_buffer(u8 *buf, size_t size)
 {
         struct scatterlist sg;
 
-        sg_init_one(&sg, random_data+data_left, RANDOM_DATA_SIZE-data_left);
+        sg_init_one(&sg, buf, size);
+
         /* There should always be room for one buffer. */
-        if (vq->vq_ops->add_buf(vq, &sg, 0, 1, random_data) < 0)
+        if (vq->vq_ops->add_buf(vq, &sg, 0, 1, buf) < 0)
                 BUG();
+
         vq->vq_ops->kick(vq);
 }
 
-/* At least we don't udelay() in a loop like some other drivers. */
-static int virtio_data_present(struct hwrng *rng, int wait)
+static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait)
 {
-        if (data_left >= sizeof(u32))
-                return 1;
 
-again:
+        if (!busy) {
+                busy = true;
+                init_completion(&have_data);
+                register_buffer(buf, size);
+        }
+
         if (!wait)
                 return 0;
 
         wait_for_completion(&have_data);
 
-        /* Not enough?  Re-register. */
-        if (unlikely(data_left < sizeof(u32))) {
-                register_buffer();
-                goto again;
-        }
+        busy = false;
 
-        return 1;
+        return data_avail;
 }
 
-/* virtio_data_present() must have succeeded before this is called. */
-static int virtio_data_read(struct hwrng *rng, u32 *data)
+static void virtio_cleanup(struct hwrng *rng)
 {
-        BUG_ON(data_left < sizeof(u32));
-        data_left -= sizeof(u32);
-        *data = random_data[data_left / 4];
-
-        if (data_left < sizeof(u32)) {
-                init_completion(&have_data);
-                register_buffer();
-        }
-        return sizeof(*data);
+        if (busy)
+                wait_for_completion(&have_data);
 }
 
+
 static struct hwrng virtio_hwrng = {
-        .name = "virtio",
-        .data_present = virtio_data_present,
-        .data_read = virtio_data_read,
+        .name           = "virtio",
+        .cleanup        = virtio_cleanup,
+        .read           = virtio_read,
 };
 
 static int virtrng_probe(struct virtio_device *vdev)
@@ -112,7 +99,6 @@ static int virtrng_probe(struct virtio_device *vdev)
                 return err;
         }
 
-        register_buffer();
         return 0;
 }
 
@@ -128,7 +114,7 @@ static struct virtio_device_id id_table[] = {
         { 0 },
 };
 
-static struct virtio_driver virtio_rng = {
+static struct virtio_driver virtio_rng_driver = {
         .driver.name =  KBUILD_MODNAME,
         .driver.owner = THIS_MODULE,
         .id_table =     id_table,
@@ -138,22 +124,12 @@ static struct virtio_driver virtio_rng = {
 
 static int __init init(void)
 {
-        int err;
-
-        random_data = kmalloc(RANDOM_DATA_SIZE, GFP_KERNEL);
-        if (!random_data)
-                return -ENOMEM;
-
-        err = register_virtio_driver(&virtio_rng);
-        if (err)
-                kfree(random_data);
-        return err;
+        return register_virtio_driver(&virtio_rng_driver);
 }
 
 static void __exit fini(void)
 {
-        kfree(random_data);
-        unregister_virtio_driver(&virtio_rng);
+        unregister_virtio_driver(&virtio_rng_driver);
 }
 module_init(init);
 module_exit(fini);