| /* |
| * OMAP4 SMP cpu-hotplug support |
| * |
| * Copyright (C) 2010 Texas Instruments, Inc. |
| * Author: |
| * Santosh Shilimkar <santosh.shilimkar@ti.com> |
| * |
| * Platform file needed for the OMAP4 SMP. This file is based on arm |
| * realview smp platform. |
| * Copyright (c) 2002 ARM Limited. |
| * |
| * 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/omap-wakeupgen.h> |
| |
| #include "common.h" |
| |
| #include "powerdomain.h" |
| |
| int platform_cpu_kill(unsigned int cpu) |
| { |
| return 1; |
| } |
| |
| /* |
| * platform-specific code to shutdown a CPU |
| * Called with IRQs disabled |
| */ |
| void __ref platform_cpu_die(unsigned int cpu) |
| { |
| unsigned int boot_cpu = 0; |
| void __iomem *base = omap_get_wakeupgen_base(); |
| |
| flush_cache_all(); |
| dsb(); |
| |
| /* |
| * we're ready for shutdown now, so do it |
| */ |
| if (omap_secure_apis_support()) { |
| if (omap_modify_auxcoreboot0(0x0, 0x200) != 0x0) |
| pr_err("Secure clear status failed\n"); |
| } else { |
| __raw_writel(0, base + OMAP_AUX_CORE_BOOT_0); |
| } |
| |
| |
| for (;;) { |
| /* |
| * Enter into low power state |
| */ |
| omap4_hotplug_cpu(cpu, PWRDM_POWER_OFF); |
| |
| if (omap_secure_apis_support()) |
| boot_cpu = omap_read_auxcoreboot0(); |
| else |
| boot_cpu = |
| __raw_readl(base + OMAP_AUX_CORE_BOOT_0) >> 5; |
| |
| if (boot_cpu == smp_processor_id()) { |
| /* |
| * OK, proper wakeup, we're done |
| */ |
| break; |
| } |
| pr_debug("CPU%u: spurious wakeup call\n", cpu); |
| } |
| } |
| |
| 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; |
| } |