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author | Arnd Bergmann <arnd@arndb.de> | 2012-12-02 15:12:47 +0100 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2013-03-12 17:39:47 +0100 |
commit | a7ed099ffc8edf2a6dccd8a22469347f5cdcfa57 (patch) | |
tree | b56901430602574233ad23008cfd7c23babd20c3 /arch/arm/mach-spear/hotplug.c | |
parent | 0ec05c3e4ac6548fcab4b6a74254a22ef251e1fd (diff) | |
download | linux-stable-a7ed099ffc8edf2a6dccd8a22469347f5cdcfa57.tar.gz linux-stable-a7ed099ffc8edf2a6dccd8a22469347f5cdcfa57.tar.bz2 linux-stable-a7ed099ffc8edf2a6dccd8a22469347f5cdcfa57.zip |
ARM: spear: move all files to mach-spear
There are no conflicting files between the three mach-spear* directories
and plat-spear any more, so we can now move all file to a common
mach-spear directory.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Diffstat (limited to 'arch/arm/mach-spear/hotplug.c')
-rw-r--r-- | arch/arm/mach-spear/hotplug.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/arch/arm/mach-spear/hotplug.c b/arch/arm/mach-spear/hotplug.c new file mode 100644 index 000000000000..a7d2dd11a4f2 --- /dev/null +++ b/arch/arm/mach-spear/hotplug.c @@ -0,0 +1,103 @@ +/* + * linux/arch/arm/mach-spear13xx/hotplug.c + * + * Copyright (C) 2012 ST Microelectronics Ltd. + * Deepak Sikri <deepak.sikri@st.com> + * + * based upon linux/arch/arm/mach-realview/hotplug.c + * + * 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 <linux/kernel.h> +#include <linux/errno.h> +#include <linux/smp.h> +#include <asm/cacheflush.h> +#include <asm/cp15.h> +#include <asm/smp_plat.h> + +static inline void cpu_enter_lowpower(void) +{ + unsigned int v; + + flush_cache_all(); + asm volatile( + " mcr p15, 0, %1, c7, c5, 0\n" + " dsb\n" + /* + * Turn off coherency + */ + " mrc p15, 0, %0, c1, c0, 1\n" + " bic %0, %0, #0x20\n" + " mcr p15, 0, %0, c1, c0, 1\n" + " mrc p15, 0, %0, c1, c0, 0\n" + " bic %0, %0, %2\n" + " mcr p15, 0, %0, c1, c0, 0\n" + : "=&r" (v) + : "r" (0), "Ir" (CR_C) + : "cc", "memory"); +} + +static inline void cpu_leave_lowpower(void) +{ + unsigned int v; + + asm volatile("mrc p15, 0, %0, c1, c0, 0\n" + " orr %0, %0, %1\n" + " mcr p15, 0, %0, c1, c0, 0\n" + " mrc p15, 0, %0, c1, c0, 1\n" + " orr %0, %0, #0x20\n" + " mcr p15, 0, %0, c1, c0, 1\n" + : "=&r" (v) + : "Ir" (CR_C) + : "cc"); +} + +static inline void spear13xx_do_lowpower(unsigned int cpu, int *spurious) +{ + for (;;) { + wfi(); + + if (pen_release == cpu) { + /* + * OK, proper wakeup, we're done + */ + break; + } + + /* + * Getting here, means that we have come out of WFI without + * having been woken up - this shouldn't happen + * + * Just note it happening - when we're woken, we can report + * its occurrence. + */ + (*spurious)++; + } +} + +/* + * platform-specific code to shutdown a CPU + * + * Called with IRQs disabled + */ +void __ref spear13xx_cpu_die(unsigned int cpu) +{ + int spurious = 0; + + /* + * we're ready for shutdown now, so do it + */ + cpu_enter_lowpower(); + spear13xx_do_lowpower(cpu, &spurious); + + /* + * bring this CPU back into the world of cache + * coherency, and then restore interrupts + */ + cpu_leave_lowpower(); + + if (spurious) + pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious); +} |