xref: /openbmc/linux/arch/arm/mach-omap2/omap-hotplug.c (revision 4e65331c6bb4a777bd61a4dac0daa9fc47777b63)
17d35b8d0SSantosh Shilimkar /*
27d35b8d0SSantosh Shilimkar  * OMAP4 SMP cpu-hotplug support
37d35b8d0SSantosh Shilimkar  *
47d35b8d0SSantosh Shilimkar  * Copyright (C) 2010 Texas Instruments, Inc.
57d35b8d0SSantosh Shilimkar  * Author:
67d35b8d0SSantosh Shilimkar  *      Santosh Shilimkar <santosh.shilimkar@ti.com>
77d35b8d0SSantosh Shilimkar  *
87d35b8d0SSantosh Shilimkar  * Platform file needed for the OMAP4 SMP. This file is based on arm
97d35b8d0SSantosh Shilimkar  * realview smp platform.
107d35b8d0SSantosh Shilimkar  * Copyright (c) 2002 ARM Limited.
117d35b8d0SSantosh Shilimkar  *
127d35b8d0SSantosh Shilimkar  * This program is free software; you can redistribute it and/or modify
137d35b8d0SSantosh Shilimkar  * it under the terms of the GNU General Public License version 2 as
147d35b8d0SSantosh Shilimkar  * published by the Free Software Foundation.
157d35b8d0SSantosh Shilimkar  */
167d35b8d0SSantosh Shilimkar 
177d35b8d0SSantosh Shilimkar #include <linux/kernel.h>
187d35b8d0SSantosh Shilimkar #include <linux/errno.h>
197d35b8d0SSantosh Shilimkar #include <linux/smp.h>
207d35b8d0SSantosh Shilimkar 
217d35b8d0SSantosh Shilimkar #include <asm/cacheflush.h>
22*4e65331cSTony Lindgren 
23*4e65331cSTony Lindgren #include "common.h"
247d35b8d0SSantosh Shilimkar 
257d35b8d0SSantosh Shilimkar int platform_cpu_kill(unsigned int cpu)
267d35b8d0SSantosh Shilimkar {
273c030beaSRussell King 	return 1;
287d35b8d0SSantosh Shilimkar }
297d35b8d0SSantosh Shilimkar 
307d35b8d0SSantosh Shilimkar /*
317d35b8d0SSantosh Shilimkar  * platform-specific code to shutdown a CPU
327d35b8d0SSantosh Shilimkar  * Called with IRQs disabled
337d35b8d0SSantosh Shilimkar  */
347d35b8d0SSantosh Shilimkar void platform_cpu_die(unsigned int cpu)
357d35b8d0SSantosh Shilimkar {
367d35b8d0SSantosh Shilimkar 	flush_cache_all();
377d35b8d0SSantosh Shilimkar 	dsb();
387d35b8d0SSantosh Shilimkar 
397d35b8d0SSantosh Shilimkar 	/*
407d35b8d0SSantosh Shilimkar 	 * we're ready for shutdown now, so do it
417d35b8d0SSantosh Shilimkar 	 */
427d35b8d0SSantosh Shilimkar 	if (omap_modify_auxcoreboot0(0x0, 0x200) != 0x0)
437d35b8d0SSantosh Shilimkar 		printk(KERN_CRIT "Secure clear status failed\n");
447d35b8d0SSantosh Shilimkar 
457d35b8d0SSantosh Shilimkar 	for (;;) {
467d35b8d0SSantosh Shilimkar 		/*
477d35b8d0SSantosh Shilimkar 		 * Execute WFI
487d35b8d0SSantosh Shilimkar 		 */
497d35b8d0SSantosh Shilimkar 		do_wfi();
507d35b8d0SSantosh Shilimkar 
517d35b8d0SSantosh Shilimkar 		if (omap_read_auxcoreboot0() == cpu) {
527d35b8d0SSantosh Shilimkar 			/*
537d35b8d0SSantosh Shilimkar 			 * OK, proper wakeup, we're done
547d35b8d0SSantosh Shilimkar 			 */
557d35b8d0SSantosh Shilimkar 			break;
567d35b8d0SSantosh Shilimkar 		}
577d35b8d0SSantosh Shilimkar 		pr_debug("CPU%u: spurious wakeup call\n", cpu);
587d35b8d0SSantosh Shilimkar 	}
597d35b8d0SSantosh Shilimkar }
607d35b8d0SSantosh Shilimkar 
617d35b8d0SSantosh Shilimkar int platform_cpu_disable(unsigned int cpu)
627d35b8d0SSantosh Shilimkar {
637d35b8d0SSantosh Shilimkar 	/*
647d35b8d0SSantosh Shilimkar 	 * we don't allow CPU 0 to be shutdown (it is still too special
657d35b8d0SSantosh Shilimkar 	 * e.g. clock tick interrupts)
667d35b8d0SSantosh Shilimkar 	 */
677d35b8d0SSantosh Shilimkar 	return cpu == 0 ? -EPERM : 0;
687d35b8d0SSantosh Shilimkar }
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