From mboxrd@z Thu Jan 1 00:00:00 1970 From: santosh.shilimkar@ti.com (Santosh Shilimkar) Date: Thu, 31 Jan 2013 21:15:50 +0530 Subject: [PATCH v3 01/15] ARM: multi-cluster PM: secondary kernel entry code In-Reply-To: <1359445870-18925-2-git-send-email-nicolas.pitre@linaro.org> References: <1359445870-18925-1-git-send-email-nicolas.pitre@linaro.org> <1359445870-18925-2-git-send-email-nicolas.pitre@linaro.org> Message-ID: <510A91AE.6050807@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tuesday 29 January 2013 01:20 PM, Nicolas Pitre wrote: > CPUs in cluster based systems, such as big.LITTLE, have special needs > when entering the kernel due to a hotplug event, or when resuming from > a deep sleep mode. > > This is vectorized so multiple CPUs can enter the kernel in parallel > without serialization. > > The mcpm prefix stands for "multi cluster power management", however > this is usable on single cluster systems as well. Only the basic > structure is introduced here. This will be extended with later patches. > > In order not to complexify things more than they currently have to, > the planned work to make runtime adjusted MPIDR based indexing and > dynamic memory allocation for cluster states is postponed to a later > cycle. The MAX_NR_CLUSTERS and MAX_CPUS_PER_CLUSTER static definitions > should be sufficient for those systems expected to be available in the > near future. > 'mcpm' sounds definitely better than 'bL' ;) > Signed-off-by: Nicolas Pitre > --- > arch/arm/Kconfig | 8 ++++ > arch/arm/common/Makefile | 1 + > arch/arm/common/mcpm_entry.c | 29 +++++++++++++ > arch/arm/common/mcpm_head.S | 86 +++++++++++++++++++++++++++++++++++++++ > arch/arm/include/asm/mcpm_entry.h | 35 ++++++++++++++++ > 5 files changed, 159 insertions(+) > create mode 100644 arch/arm/common/mcpm_entry.c > create mode 100644 arch/arm/common/mcpm_head.S > create mode 100644 arch/arm/include/asm/mcpm_entry.h > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index 67874b82a4..200f559c1c 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -1584,6 +1584,14 @@ config HAVE_ARM_TWD > help > This options enables support for the ARM timer and watchdog unit > > +config CLUSTER_PM > + bool "Cluster Power Management Infrastructure" > + depends on CPU_V7 && SMP > + help > + This option provides the common power management infrastructure > + for (multi-)cluster based systems, such as big.LITTLE based > + systems. > + > choice > prompt "Memory split" > default VMSPLIT_3G > diff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile > index e8a4e58f1b..23e85b1fae 100644 > --- a/arch/arm/common/Makefile > +++ b/arch/arm/common/Makefile > @@ -13,3 +13,4 @@ obj-$(CONFIG_SHARP_PARAM) += sharpsl_param.o > obj-$(CONFIG_SHARP_SCOOP) += scoop.o > obj-$(CONFIG_PCI_HOST_ITE8152) += it8152.o > obj-$(CONFIG_ARM_TIMER_SP804) += timer-sp.o > +obj-$(CONFIG_CLUSTER_PM) += mcpm_head.o mcpm_entry.o > diff --git a/arch/arm/common/mcpm_entry.c b/arch/arm/common/mcpm_entry.c > new file mode 100644 > index 0000000000..3a6d7e70fd > --- /dev/null > +++ b/arch/arm/common/mcpm_entry.c > @@ -0,0 +1,29 @@ > +/* > + * arch/arm/common/mcpm_entry.c -- entry point for multi-cluster PM > + * > + * Created by: Nicolas Pitre, March 2012 > + * Copyright: (C) 2012-2013 Linaro Limited > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > + > +#include > +#include > + > +#include > +#include > +#include > +#include > + > +extern volatile unsigned long mcpm_entry_vectors[MAX_NR_CLUSTERS][MAX_CPUS_PER_CLUSTER]; > + > +void mcpm_set_entry_vector(unsigned cpu, unsigned cluster, void *ptr) > +{ > + unsigned long val = ptr ? virt_to_phys(ptr) : 0; May be extra line would be good here. Patch looks fine to my eyes otherwise. Reviewed-by: Santosh Shilimkar