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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-17 19:08:06 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-17 19:08:06 -0700
commit411f5c7a502769ccc0377c5ba36cb0b283847ba8 (patch)
tree2c3a29671e3f923de48c55f94194849264a7bf53 /arch/arm/mach-exynos4/hotplug.c
parent6d7ed21d17e640b120b902a314143e5ef4917a70 (diff)
parent9ced9f03d12d7539e86b0bff5bc750153c976c34 (diff)
Merge branch 'devel-stable' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel-stable' of master.kernel.org:/home/rmk/linux-2.6-arm: (289 commits) davinci: DM644x EVM: register MUSB device earlier davinci: add spi devices on tnetv107x evm davinci: add ssp config for tnetv107x evm board davinci: add tnetv107x ssp platform device spi: add ti-ssp spi master driver mfd: add driver for sequencer serial port ARM: EXYNOS4: Implement Clock gating for System MMU ARM: EXYNOS4: Enhancement of System MMU driver ARM: EXYNOS4: Add support for gpio interrupts ARM: S5P: Add function to register gpio interrupt bank data ARM: S5P: Cleanup S5P gpio interrupt code ARM: EXYNOS4: Add missing GPYx banks ARM: S3C64XX: Fix section mismatch from cpufreq init ARM: EXYNOS4: Add keypad device to the SMDKV310 ARM: EXYNOS4: Update clocks for keypad ARM: EXYNOS4: Update keypad base address ARM: EXYNOS4: Add keypad device helpers ARM: EXYNOS4: Add support for SATA on ARMLEX4210 plat-nomadik: make GPIO interrupts work with cpuidle ApSleep mach-u300: define a dummy filter function for coh901318 ... Fix up various conflicts in - arch/arm/mach-exynos4/cpufreq.c - arch/arm/mach-mxs/gpio.c - drivers/net/Kconfig - drivers/tty/serial/Kconfig - drivers/tty/serial/Makefile - drivers/usb/gadget/fsl_mxc_udc.c - drivers/video/Kconfig
Diffstat (limited to 'arch/arm/mach-exynos4/hotplug.c')
-rw-r--r--arch/arm/mach-exynos4/hotplug.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/arm/mach-exynos4/hotplug.c b/arch/arm/mach-exynos4/hotplug.c
new file mode 100644
index 00000000000..2b5909e2ccd
--- /dev/null
+++ b/arch/arm/mach-exynos4/hotplug.c
@@ -0,0 +1,130 @@
+/* linux arch/arm/mach-exynos4/hotplug.c
+ *
+ * Cloned from linux/arch/arm/mach-realview/hotplug.c
+ *
+ * Copyright (C) 2002 ARM Ltd.
+ * All Rights Reserved
+ *
+ * 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>
+
+extern volatile int pen_release;
+
+static inline void cpu_enter_lowpower(void)
+{
+ unsigned int v;
+
+ flush_cache_all();
+ asm volatile(
+ " mcr p15, 0, %1, c7, c5, 0\n"
+ " mcr p15, 0, %1, c7, c10, 4\n"
+ /*
+ * Turn off coherency
+ */
+ " mrc p15, 0, %0, c1, c0, 1\n"
+ " bic %0, %0, %3\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), "Ir" (0x40)
+ : "cc");
+}
+
+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, %2\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ : "=&r" (v)
+ : "Ir" (CR_C), "Ir" (0x40)
+ : "cc");
+}
+
+static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
+{
+ /*
+ * there is no power-control hardware on this platform, so all
+ * we can do is put the core into WFI; this is safe as the calling
+ * code will have already disabled interrupts
+ */
+ for (;;) {
+ /*
+ * here's the WFI
+ */
+ asm(".word 0xe320f003\n"
+ :
+ :
+ : "memory", "cc");
+
+ 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)++;
+ }
+}
+
+int platform_cpu_kill(unsigned int cpu)
+{
+ return 1;
+}
+
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+void platform_cpu_die(unsigned int cpu)
+{
+ int spurious = 0;
+
+ /*
+ * we're ready for shutdown now, so do it
+ */
+ cpu_enter_lowpower();
+ platform_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);
+}
+
+int platform_cpu_disable(unsigned int cpu)
+{
+ /*
+ * we don't allow CPU 0 to be shutdown (it is still too special
+ * e.g. clock tick interrupts)
+ */
+ return cpu == 0 ? -EPERM : 0;
+}