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authorLinus Torvalds <torvalds@linux-foundation.org>2010-10-30 08:26:25 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-10-30 08:26:25 -0700
commit706d4b12f8d7edd28d7e879a77235472da393edb (patch)
treec9bc1ce06b1154a49da1d0d907cac544a818eb0e /arch/arm/mach-s5pv310/hotplug.c
parent3af54c9bd9e6f14f896aac1bb0e8405ae0bc7a44 (diff)
parent9bafc74163d8bccca9810159aab39be926fb877c (diff)
Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (215 commits) ARM: memblock: setup lowmem mappings using memblock ARM: memblock: move meminfo into find_limits directly ARM: memblock: convert free_highpages() to use memblock ARM: move freeing of highmem pages out of mem_init() ARM: memblock: convert memory detail printing to use memblock ARM: memblock: use memblock to free memory into arm_bootmem_init() ARM: memblock: use memblock when initializing memory allocators ARM: ensure membank array is always sorted ARM: 6466/1: implement flush_icache_all for the rest of the CPUs ARM: 6464/2: fix spinlock recursion in adjust_pte() ARM: fix memblock breakage ARM: 6465/1: Fix data abort accessing proc_info from __lookup_processor_type ARM: 6460/1: ixp2000: fix type of ixp2000_timer_interrupt ARM: 6449/1: Fix for compiler warning of uninitialized variable. ARM: 6445/1: fixup TCM memory types ARM: imx: Add wake functionality to GPIO ARM: mx5: Add gpio-keys to mx51 babbage board ARM: imx: Add gpio-keys to plat-mxc mx31_3ds: Fix spi registration mx31_3ds: Fix the logic for detecting the debug board ...
Diffstat (limited to 'arch/arm/mach-s5pv310/hotplug.c')
-rw-r--r--arch/arm/mach-s5pv310/hotplug.c144
1 files changed, 144 insertions, 0 deletions
diff --git a/arch/arm/mach-s5pv310/hotplug.c b/arch/arm/mach-s5pv310/hotplug.c
new file mode 100644
index 00000000000..03652c3605f
--- /dev/null
+++ b/arch/arm/mach-s5pv310/hotplug.c
@@ -0,0 +1,144 @@
+/* linux arch/arm/mach-s5pv310/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 <linux/completion.h>
+
+#include <asm/cacheflush.h>
+
+extern volatile int pen_release;
+
+static DECLARE_COMPLETION(cpu_killed);
+
+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, #0x20\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ " mrc p15, 0, %0, c1, c0, 0\n"
+ " bic %0, %0, #0x04\n"
+ " mcr p15, 0, %0, c1, c0, 0\n"
+ : "=&r" (v)
+ : "r" (0)
+ : "cc");
+}
+
+static inline void cpu_leave_lowpower(void)
+{
+ unsigned int v;
+
+ asm volatile(
+ "mrc p15, 0, %0, c1, c0, 0\n"
+ " orr %0, %0, #0x04\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)
+ :
+ : "cc");
+}
+
+static inline void platform_do_lowpower(unsigned int cpu)
+{
+ /*
+ * 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
+ *
+ * The trouble is, letting people know about this is not really
+ * possible, since we are currently running incoherently, and
+ * therefore cannot safely call printk() or anything else
+ */
+#ifdef DEBUG
+ printk(KERN_WARN "CPU%u: spurious wakeup call\n", cpu);
+#endif
+ }
+}
+
+int platform_cpu_kill(unsigned int cpu)
+{
+ return wait_for_completion_timeout(&cpu_killed, 5000);
+}
+
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+void platform_cpu_die(unsigned int cpu)
+{
+#ifdef DEBUG
+ unsigned int this_cpu = hard_smp_processor_id();
+
+ if (cpu != this_cpu) {
+ printk(KERN_CRIT "Eek! platform_cpu_die running on %u, should be %u\n",
+ this_cpu, cpu);
+ BUG();
+ }
+#endif
+
+ printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
+ complete(&cpu_killed);
+
+ /*
+ * we're ready for shutdown now, so do it
+ */
+ cpu_enter_lowpower();
+ platform_do_lowpower(cpu);
+
+ /*
+ * bring this CPU back into the world of cache
+ * coherency, and then restore interrupts
+ */
+ cpu_leave_lowpower();
+}
+
+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;
+}