Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 1 | /* |
| 2 | * OMAP4 SMP cpu-hotplug support |
| 3 | * |
| 4 | * Copyright (C) 2010 Texas Instruments, Inc. |
| 5 | * Author: |
| 6 | * Santosh Shilimkar <santosh.shilimkar@ti.com> |
| 7 | * |
| 8 | * Platform file needed for the OMAP4 SMP. This file is based on arm |
| 9 | * realview smp platform. |
| 10 | * Copyright (c) 2002 ARM Limited. |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License version 2 as |
| 14 | * published by the Free Software Foundation. |
| 15 | */ |
| 16 | |
| 17 | #include <linux/kernel.h> |
| 18 | #include <linux/errno.h> |
| 19 | #include <linux/smp.h> |
Santosh Shilimkar | 247c445 | 2012-05-09 20:38:35 +0530 | [diff] [blame^] | 20 | #include <linux/io.h> |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 21 | |
| 22 | #include <asm/cacheflush.h> |
Santosh Shilimkar | 247c445 | 2012-05-09 20:38:35 +0530 | [diff] [blame^] | 23 | #include <mach/omap-wakeupgen.h> |
Tony Lindgren | 4e65331 | 2011-11-10 22:45:17 +0100 | [diff] [blame] | 24 | |
| 25 | #include "common.h" |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 26 | |
Santosh Shilimkar | b5b4f28 | 2010-06-16 22:19:48 +0530 | [diff] [blame] | 27 | #include "powerdomain.h" |
| 28 | |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 29 | int platform_cpu_kill(unsigned int cpu) |
| 30 | { |
Russell King | 3c030be | 2010-11-30 11:07:35 +0000 | [diff] [blame] | 31 | return 1; |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 32 | } |
| 33 | |
| 34 | /* |
| 35 | * platform-specific code to shutdown a CPU |
| 36 | * Called with IRQs disabled |
| 37 | */ |
Santosh Shilimkar | 82dfcbf | 2012-02-22 16:10:04 +0530 | [diff] [blame] | 38 | void __ref platform_cpu_die(unsigned int cpu) |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 39 | { |
Santosh Shilimkar | 247c445 | 2012-05-09 20:38:35 +0530 | [diff] [blame^] | 40 | unsigned int boot_cpu = 0; |
| 41 | void __iomem *base = omap_get_wakeupgen_base(); |
Santosh Shilimkar | b5b4f28 | 2010-06-16 22:19:48 +0530 | [diff] [blame] | 42 | |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 43 | flush_cache_all(); |
| 44 | dsb(); |
| 45 | |
| 46 | /* |
| 47 | * we're ready for shutdown now, so do it |
| 48 | */ |
Santosh Shilimkar | 247c445 | 2012-05-09 20:38:35 +0530 | [diff] [blame^] | 49 | if (omap_secure_apis_support()) { |
| 50 | if (omap_modify_auxcoreboot0(0x0, 0x200) != 0x0) |
| 51 | pr_err("Secure clear status failed\n"); |
| 52 | } else { |
| 53 | __raw_writel(0, base + OMAP_AUX_CORE_BOOT_0); |
| 54 | } |
| 55 | |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 56 | |
| 57 | for (;;) { |
| 58 | /* |
Santosh Shilimkar | b5b4f28 | 2010-06-16 22:19:48 +0530 | [diff] [blame] | 59 | * Enter into low power state |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 60 | */ |
Santosh Shilimkar | b5b4f28 | 2010-06-16 22:19:48 +0530 | [diff] [blame] | 61 | omap4_hotplug_cpu(cpu, PWRDM_POWER_OFF); |
Santosh Shilimkar | 247c445 | 2012-05-09 20:38:35 +0530 | [diff] [blame^] | 62 | |
| 63 | if (omap_secure_apis_support()) |
| 64 | boot_cpu = omap_read_auxcoreboot0(); |
| 65 | else |
| 66 | boot_cpu = |
| 67 | __raw_readl(base + OMAP_AUX_CORE_BOOT_0) >> 5; |
| 68 | |
| 69 | if (boot_cpu == smp_processor_id()) { |
Santosh Shilimkar | 7d35b8d | 2010-08-02 13:18:19 +0300 | [diff] [blame] | 70 | /* |
| 71 | * OK, proper wakeup, we're done |
| 72 | */ |
| 73 | break; |
| 74 | } |
| 75 | pr_debug("CPU%u: spurious wakeup call\n", cpu); |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | int platform_cpu_disable(unsigned int cpu) |
| 80 | { |
| 81 | /* |
| 82 | * we don't allow CPU 0 to be shutdown (it is still too special |
| 83 | * e.g. clock tick interrupts) |
| 84 | */ |
| 85 | return cpu == 0 ? -EPERM : 0; |
| 86 | } |