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2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-23powerpc: Use hardware RNG for arch_get_random_seed_* not arch_get_random_*Paul Mackerras
The hardware RNG on POWER8 and POWER7+ can be relatively slow, since it can only supply one 64-bit value per microsecond. Currently we read it in arch_get_random_long(), but that slows down reading from /dev/urandom since the code in random.c calls arch_get_random_long() for every longword read from /dev/urandom. Since the hardware RNG supplies high-quality entropy on every read, it matches the semantics of arch_get_random_seed_long() better than those of arch_get_random_long(). Therefore this commit makes the code use the POWER8/7+ hardware RNG only for arch_get_random_seed_{long,int} and not for arch_get_random_{long,int}. This won't affect any other PowerPC-based platforms because none of them currently support a hardware RNG. To make it clear that the ppc_md function pointer is used for arch_get_random_seed_*, we rename it from get_random_long to get_random_seed. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-07-28powerpc/pseries: Switch pseries drivers to use machine_xxx_initcall()Michael Ellerman
A lot of the code in platforms/pseries is using non-machine initcalls. That means if a kernel built with pseries support runs on another platform, for example powernv, the initcalls will still run. Most of these cases are OK, though sometimes only due to luck. Some were having more effect: * hcall_inst_init - Checking FW_FEATURE_LPAR which is set on ps3 & celleb. * mobility_sysfs_init - created sysfs files unconditionally - but no effect due to ENOSYS from rtas_ibm_suspend_me() * apo_pm_init - created sysfs, allows write - nothing checks the value written to though * alloc_dispatch_log_kmem_cache - creating kmem_cache on non-pseries machines Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-11-21powerpc/pseries: Fix SMP=n build of rng.cMichael Ellerman
In commit a489043 "Implement arch_get_random_long() based on H_RANDOM" I broke the SMP=n build. We were getting plpar_wrappers.h via spinlock.h which breaks when SMP=n. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-11powerpc/pseries: Implement arch_get_random_long() based on H_RANDOMMichael Ellerman
Add support for the arch_get_random_long() hook based on the H_RANDOM hypervisor call. We trust the hypervisor to provide us with random data, ie. we don't whiten it in anyway. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>