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> 224e65331cSTony Lindgren 234e65331cSTony Lindgren #include "common.h" 247d35b8d0SSantosh Shilimkar 25*b5b4f288SSantosh Shilimkar #include "powerdomain.h" 26*b5b4f288SSantosh Shilimkar 277d35b8d0SSantosh Shilimkar int platform_cpu_kill(unsigned int cpu) 287d35b8d0SSantosh Shilimkar { 293c030beaSRussell King return 1; 307d35b8d0SSantosh Shilimkar } 317d35b8d0SSantosh Shilimkar 327d35b8d0SSantosh Shilimkar /* 337d35b8d0SSantosh Shilimkar * platform-specific code to shutdown a CPU 347d35b8d0SSantosh Shilimkar * Called with IRQs disabled 357d35b8d0SSantosh Shilimkar */ 367d35b8d0SSantosh Shilimkar void platform_cpu_die(unsigned int cpu) 377d35b8d0SSantosh Shilimkar { 38*b5b4f288SSantosh Shilimkar unsigned int this_cpu; 39*b5b4f288SSantosh Shilimkar 407d35b8d0SSantosh Shilimkar flush_cache_all(); 417d35b8d0SSantosh Shilimkar dsb(); 427d35b8d0SSantosh Shilimkar 437d35b8d0SSantosh Shilimkar /* 447d35b8d0SSantosh Shilimkar * we're ready for shutdown now, so do it 457d35b8d0SSantosh Shilimkar */ 467d35b8d0SSantosh Shilimkar if (omap_modify_auxcoreboot0(0x0, 0x200) != 0x0) 47*b5b4f288SSantosh Shilimkar pr_err("Secure clear status failed\n"); 487d35b8d0SSantosh Shilimkar 497d35b8d0SSantosh Shilimkar for (;;) { 507d35b8d0SSantosh Shilimkar /* 51*b5b4f288SSantosh Shilimkar * Enter into low power state 527d35b8d0SSantosh Shilimkar */ 53*b5b4f288SSantosh Shilimkar omap4_hotplug_cpu(cpu, PWRDM_POWER_OFF); 54*b5b4f288SSantosh Shilimkar this_cpu = smp_processor_id(); 55*b5b4f288SSantosh Shilimkar if (omap_read_auxcoreboot0() == this_cpu) { 567d35b8d0SSantosh Shilimkar /* 577d35b8d0SSantosh Shilimkar * OK, proper wakeup, we're done 587d35b8d0SSantosh Shilimkar */ 597d35b8d0SSantosh Shilimkar break; 607d35b8d0SSantosh Shilimkar } 617d35b8d0SSantosh Shilimkar pr_debug("CPU%u: spurious wakeup call\n", cpu); 627d35b8d0SSantosh Shilimkar } 637d35b8d0SSantosh Shilimkar } 647d35b8d0SSantosh Shilimkar 657d35b8d0SSantosh Shilimkar int platform_cpu_disable(unsigned int cpu) 667d35b8d0SSantosh Shilimkar { 677d35b8d0SSantosh Shilimkar /* 687d35b8d0SSantosh Shilimkar * we don't allow CPU 0 to be shutdown (it is still too special 697d35b8d0SSantosh Shilimkar * e.g. clock tick interrupts) 707d35b8d0SSantosh Shilimkar */ 717d35b8d0SSantosh Shilimkar return cpu == 0 ? -EPERM : 0; 727d35b8d0SSantosh Shilimkar } 73