Initial file dump from open source releaseHEADmaster

1 files changed, 167 insertions, 0 deletions

diff --git a/drivers/platform/sprd/hotplug.c b/drivers/platform/sprd/hotplug.c
new file mode 100644
index 00000000..cf176183
--- /dev/null
+++ b/drivers/platform/sprd/hotplug.c
@@ -0,0 +1,167 @@
+/* linux arch/arm/mach-sc8830/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 <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/io.h>
+
+#include <soc/sprd/hardware.h>
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/smp_plat.h>
+#include <soc/sprd/sci.h>
+#include <soc/sprd/sci_glb_regs.h>
+
+extern volatile int pen_release;
+#ifdef CONFIG_ARCH_SCX35
+int powerdown_cpus(int cpu);
+int sci_shark_enter_lowpower(void);
+#endif
+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, %2\n"
+	"	mcr	p15, 0, %0, c1, c0, 0\n"
+	  : "=&r" (v)
+	  : "r" (0), "Ir" (CR_C)
+	  : "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, #0x20\n"
+	"	mcr	p15, 0, %0, c1, c0, 1\n"
+	  : "=&r" (v)
+	  : "Ir" (CR_C)
+	  : "cc");
+}
+
+extern unsigned int  sprd_boot_magnum;
+
+static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
+{
+	unsigned int val = sprd_boot_magnum;
+
+	/*
+	 * 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
+	 */
+
+	val |= (cpu_logical_map(cpu) & 0x0000000f);
+	for (;;) {
+		/*
+		 * here's the WFI
+		 */
+		asm(".word	0xe320f003\n"
+		    :
+		    :
+		    : "memory", "cc");
+
+		if (pen_release == val) {
+			/*
+			 * OK, proper wakeup, we're done
+			 */
+			 pr_info("platform_do_lowpower %x %x\n",pen_release,val);
+			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 sprd_cpu_kill(unsigned int cpu)
+{
+#ifdef CONFIG_ARCH_SCX35
+	int i = 0;
+	printk("!! %d  platform_cpu_kill %d !!\n", smp_processor_id(), cpu);
+	while (i < 20) {
+		//check wfi?
+		if (sci_glb_read(REG_AP_AHB_CA7_STANDBY_STATUS, -1UL) & (1 << cpu_logical_map(cpu)))
+		{
+			powerdown_cpus(cpu);
+			break;
+		}
+		udelay(100);
+		i++;
+	}
+	printk("platform_cpu_kill finished i=%d !!\n", i);
+	return (i >= 20? 0 : 1);
+#endif
+	return 1;
+}
+
+/*
+ * platform-specific code to shutdown a CPU
+ *
+ * Called with IRQs disabled
+ */
+void __cpuinit sprd_cpu_die(unsigned int cpu)
+{
+	int spurious = 0;
+
+#ifdef CONFIG_ARCH_SCX35
+	sci_shark_enter_lowpower();
+	panic("shouldn't be here \n");
+#endif
+	/*
+	 * 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 sprd_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;
+}