diff options
Diffstat (limited to 'arch/powerpc/platforms/pasemi/idle.c')
-rw-r--r-- | arch/powerpc/platforms/pasemi/idle.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pasemi/idle.c b/arch/powerpc/platforms/pasemi/idle.c new file mode 100644 index 000000000..8bb4e8082 --- /dev/null +++ b/arch/powerpc/platforms/pasemi/idle.c @@ -0,0 +1,105 @@ +/* + * Copyright (C) 2006-2007 PA Semi, Inc + * + * Maintained by: Olof Johansson <olof@lixom.net> + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#undef DEBUG + +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/irq.h> + +#include <asm/machdep.h> +#include <asm/reg.h> +#include <asm/smp.h> + +#include "pasemi.h" + +struct sleep_mode { + char *name; + void (*entry)(void); +}; + +static struct sleep_mode modes[] = { + { .name = "spin", .entry = &idle_spin }, + { .name = "doze", .entry = &idle_doze }, +}; + +static int current_mode = 0; + +static int pasemi_system_reset_exception(struct pt_regs *regs) +{ + /* If we were woken up from power savings, we need to return + * to the calling function, since nip is not saved across + * all modes. + */ + + if (regs->msr & SRR1_WAKEMASK) + regs->nip = regs->link; + + switch (regs->msr & SRR1_WAKEMASK) { + case SRR1_WAKEDEC: + set_dec(1); + case SRR1_WAKEEE: + /* + * Handle these when interrupts get re-enabled and we take + * them as regular exceptions. We are in an NMI context + * and can't handle these here. + */ + break; + default: + /* do system reset */ + return 0; + } + + /* Set higher astate since we come out of power savings at 0 */ + restore_astate(hard_smp_processor_id()); + + /* everything handled */ + regs->msr |= MSR_RI; + return 1; +} + +static int __init pasemi_idle_init(void) +{ +#ifndef CONFIG_PPC_PASEMI_CPUFREQ + pr_warn("No cpufreq driver, powersavings modes disabled\n"); + current_mode = 0; +#endif + + ppc_md.system_reset_exception = pasemi_system_reset_exception; + ppc_md.power_save = modes[current_mode].entry; + pr_info("Using PA6T idle loop (%s)\n", modes[current_mode].name); + + return 0; +} +machine_late_initcall(pasemi, pasemi_idle_init); + +static int __init idle_param(char *p) +{ + int i; + for (i = 0; i < ARRAY_SIZE(modes); i++) { + if (!strcmp(modes[i].name, p)) { + current_mode = i; + break; + } + } + return 0; +} + +early_param("idle", idle_param); |