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authorKukjin Kim <kgene.kim@samsung.com>2011-11-06 13:54:56 +0900
committerKukjin Kim <kgene.kim@samsung.com>2011-11-06 13:54:56 +0900
commit830145796a5c8f1ca3f87ea619063c1d99a57df5 (patch)
treee72a0ecacfcce228c46d93c946cfd65a44cc1fd3 /arch/arm/mach-exynos/hotplug.c
parente700e41d9abfbf9fee01e979a41b185695132c19 (diff)
downloadlinux-stericsson-830145796a5c8f1ca3f87ea619063c1d99a57df5.tar.gz
ARM: EXYNOS: Add ARCH_EXYNOS and reorganize arch/arm/mach-exynos
The arch/arm/mach-exynos4 directory (CONFIG_ARCH_EXYNOS4) has made for plaforms based on EXYNOS4 SoCs. But since upcoming Samsung's SoCs such as EXYNOS5 (ARM Cortex A15) can reuse most codes in current mach-exynos4, one mach-exynos directory will be used for them. This patch changes to CONFIG_ARCH_EXYNOS (arch/arm/mach-exynos) but keeps original CONFIG_ARCH_EXYNOS4 in mach-exynos/Kconfig to avoid changing in driver side. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Diffstat (limited to 'arch/arm/mach-exynos/hotplug.c')
-rw-r--r--arch/arm/mach-exynos/hotplug.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
new file mode 100644
index 000000000000..da70e7e39937
--- /dev/null
+++ b/arch/arm/mach-exynos/hotplug.c
@@ -0,0 +1,133 @@
+/* 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 <linux/io.h>
+
+#include <asm/cacheflush.h>
+
+#include <mach/regs-pmu.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)
+{
+ for (;;) {
+
+ /* make cpu1 to be turned off at next WFI command */
+ if (cpu == 1)
+ __raw_writel(0, S5P_ARM_CORE1_CONFIGURATION);
+
+ /*
+ * here's the WFI
+ */
+ asm(".word 0xe320f003\n"
+ :
+ :
+ : "memory", "cc");
+
+ if (pen_release == cpu_logical_map(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;
+}