[PATCH 1/4] ARM: Add SMP_ON_UP Kconfig option for booting SMP kernel on UP
From: tony@atomide.com (Tony Lindgren)
Date: 2010-08-17 10:53:19
Also in:
linux-omap
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
Add Kconfig option to boot SMP kernel on uniprocessor systems, and define MULTI_CPU, MULTI_TLB and MULTI_CACHE when SMP_ON_UP option is set. This will allow us to dynamically set the uniprocessor functions during the boot in a way that should also work with ZBOOT_ROM. Signed-off-by: Tony Lindgren <tony@atomide.com> --- arch/arm/Kconfig | 7 +++++++ arch/arm/include/asm/cacheflush.h | 6 ++++++ arch/arm/include/asm/proc-fns.h | 8 ++++++++ arch/arm/include/asm/tlbflush.h | 6 ++++++ 4 files changed, 27 insertions(+), 0 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 9295110..1e9df6d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig@@ -1166,6 +1166,13 @@ config SMP If you don't know what to do here, say N. +config SMP_ON_UP + bool "Allow booting SMP kernel on uniprocessor systems (EXPERIMENTAL)" + depends on SMP + default y + help + Allows booting SMP kernel on uniprocessor systems. + config HAVE_ARM_SCU bool depends on SMP
diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h
index 4656a24..e0ed5b4 100644
--- a/arch/arm/include/asm/cacheflush.h
+++ b/arch/arm/include/asm/cacheflush.h@@ -26,6 +26,12 @@ #undef _CACHE #undef MULTI_CACHE +/* Force multiple cache support to boot SMP kernel on uniprocessor systems */ +#ifdef CONFIG_SMP_ON_UP +# undef MULTI_CACHE +# define MULTI_CACHE 1 +#endif + #if defined(CONFIG_CPU_CACHE_V3) # ifdef _CACHE # define MULTI_CACHE 1
diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h
index 8fdae9b..87a558b 100644
--- a/arch/arm/include/asm/proc-fns.h
+++ b/arch/arm/include/asm/proc-fns.h@@ -20,6 +20,14 @@ #undef MULTI_CPU #undef CPU_NAME +/* Force multiple CPU support to boot SMP kernel on uniprocessor systems */ +#ifdef CONFIG_SMP_ON_UP +# undef MULTI_CPU +# undef CPU_NAME +# define MULTI_CPU +# define CPU_NAME +#endif + /* * CPU_NAME - the prefix for CPU related functions */
diff --git a/arch/arm/include/asm/tlbflush.h b/arch/arm/include/asm/tlbflush.h
index 33b546a..9b310bd 100644
--- a/arch/arm/include/asm/tlbflush.h
+++ b/arch/arm/include/asm/tlbflush.h@@ -70,6 +70,12 @@ #undef _TLB #undef MULTI_TLB +/* Force multiple TLB support to boot SMP kernel on uniprocessor systems */ +#ifdef CONFIG_SMP_ON_UP +# undef MULTI_TLB +# define MULTI_TLB 1 +#endif + #define v3_tlb_flags (TLB_V3_FULL | TLB_V3_PAGE) #ifdef CONFIG_CPU_TLB_V3