Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

Pull powerpc updates from Benjamin Herrenschmidt:
 "The bulk of this is LE updates.  One should now be able to build an LE
  kernel and even run some things in it.

  I'm still sitting on a handful of patches to enable the new ABI that I
  *might* still send this merge window around, but due to the
  incertainty (they are pretty fresh) I want to keep them separate.

  Other notable changes are some infrastructure bits to better handle
  PCI pass-through under KVM, some bits and pieces added to the new
  PowerNV platform support such as access to the CPU SCOM bus via sysfs,
  and support for EEH error handling on PHB3 (Power8 PCIe).

  We also grew arch_get_random_long() for both pseries and powernv when
  running on P7+ and P8, exploiting the HW rng.

  And finally various embedded updates from freescale"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (154 commits)
  powerpc: Fix fatal SLB miss when restoring PPR
  powerpc/powernv: Reserve the correct PE number
  powerpc/powernv: Add PE to its own PELTV
  powerpc/powernv: Add support for indirect XSCOM via debugfs
  powerpc/scom: Improve debugfs interface
  powerpc/scom: Enable 64-bit addresses
  powerpc/boot: Properly handle the base "of" boot wrapper
  powerpc/bpf: Support MOD operation
  powerpc/bpf: Fix DIVWU instruction opcode
  of: Move definition of of_find_next_cache_node into common code.
  powerpc: Remove big endianness assumption in of_find_next_cache_node
  powerpc/tm: Remove interrupt disable in __switch_to()
  powerpc: word-at-a-time optimization for 64-bit Little Endian
  powerpc/bpf: BPF JIT compiler for 64-bit Little Endian
  powerpc: Only save/restore SDR1 if in hypervisor mode
  powerpc/pmu: Fix ADB_PMU_LED_IDE dependencies
  powerpc/nvram: Fix endian issue when using the partition length
  powerpc/nvram: Fix endian issue when reading the NVRAM size
  powerpc/nvram: Scan partitions only once
  powerpc/mpc512x: remove unnecessary #if
  ...

drivers/char/hw_random/Kconfig

@@ -290,6 +290,19 @@ config HW_RANDOM_PSERIES
 
 	  If unsure, say Y.
 
+config HW_RANDOM_POWERNV
+	tristate "PowerNV Random Number Generator support"
+	depends on HW_RANDOM && PPC_POWERNV
+	default HW_RANDOM
+	---help---
+	  This is the driver for Random Number Generator hardware found
+	  in POWER7+ and above machines for PowerNV platform.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called powernv-rng.
+
+	  If unsure, say Y.
+
 config HW_RANDOM_EXYNOS
 	tristate "EXYNOS HW random number generator support"
 	depends on HW_RANDOM && HAS_IOMEM && HAVE_CLK

drivers/char/hw_random/Makefile

@@ -24,6 +24,7 @@ obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
 obj-$(CONFIG_HW_RANDOM_PICOXCELL) += picoxcell-rng.o
 obj-$(CONFIG_HW_RANDOM_PPC4XX) += ppc4xx-rng.o
 obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o
+obj-$(CONFIG_HW_RANDOM_POWERNV) += powernv-rng.o
 obj-$(CONFIG_HW_RANDOM_EXYNOS)	+= exynos-rng.o
 obj-$(CONFIG_HW_RANDOM_TPM) += tpm-rng.o
 obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o

drivers/char/hw_random/powernv-rng.c

@@ -0,0 +1,81 @@
+/*
+ * Copyright 2013 Michael Ellerman, Guo Chao, IBM Corp.
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/random.h>
+#include <linux/hw_random.h>
+
+static int powernv_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+	unsigned long *buf;
+	int i, len;
+
+	/* We rely on rng_buffer_size() being >= sizeof(unsigned long) */
+	len = max / sizeof(unsigned long);
+
+	buf = (unsigned long *)data;
+
+	for (i = 0; i < len; i++)
+		powernv_get_random_long(buf++);
+
+	return len * sizeof(unsigned long);
+}
+
+static struct hwrng powernv_hwrng = {
+	.name = "powernv-rng",
+	.read = powernv_rng_read,
+};
+
+static int powernv_rng_remove(struct platform_device *pdev)
+{
+	hwrng_unregister(&powernv_hwrng);
+
+	return 0;
+}
+
+static int powernv_rng_probe(struct platform_device *pdev)
+{
+	int rc;
+
+	rc = hwrng_register(&powernv_hwrng);
+	if (rc) {
+		/* We only register one device, ignore any others */
+		if (rc == -EEXIST)
+			rc = -ENODEV;
+
+		return rc;
+	}
+
+	pr_info("Registered powernv hwrng.\n");
+
+	return 0;
+}
+
+static struct of_device_id powernv_rng_match[] = {
+	{ .compatible	= "ibm,power-rng",},
+	{},
+};
+MODULE_DEVICE_TABLE(of, powernv_rng_match);
+
+static struct platform_driver powernv_rng_driver = {
+	.driver = {
+		.name = "powernv_rng",
+		.of_match_table = powernv_rng_match,
+	},
+	.probe	= powernv_rng_probe,
+	.remove = powernv_rng_remove,
+};
+module_platform_driver(powernv_rng_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Bare metal HWRNG driver for POWER7+ and above");

drivers/char/hw_random/pseries-rng.c

@@ -17,6 +17,9 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/hw_random.h>
 #include <asm/vio.h>
@@ -25,10 +28,15 @@
 
 static int pseries_rng_data_read(struct hwrng *rng, u32 *data)
 {
-	if (plpar_hcall(H_RANDOM, (unsigned long *)data) != H_SUCCESS) {
-		printk(KERN_ERR "pseries rng hcall error\n");
-		return 0;
+	int rc;
+
+	rc = plpar_hcall(H_RANDOM, (unsigned long *)data);
+	if (rc != H_SUCCESS) {
+		pr_err_ratelimited("H_RANDOM call failed %d\n", rc);
+		return -EIO;
 	}
+
+	/* The hypervisor interface returns 64 bits */
 	return 8;
 }