| /* | 
 |  * Author: Kumar Gala <galak@kernel.crashing.org> | 
 |  * | 
 |  * Copyright 2009 Freescale Semiconductor Inc. | 
 |  * | 
 |  * This program is free software; you can redistribute  it and/or modify it | 
 |  * under  the terms of  the GNU General  Public License as published by the | 
 |  * Free Software Foundation;  either version 2 of the  License, or (at your | 
 |  * option) any later version. | 
 |  */ | 
 |  | 
 | #include <linux/stddef.h> | 
 | #include <linux/kernel.h> | 
 | #include <linux/smp.h> | 
 | #include <linux/threads.h> | 
 | #include <linux/hardirq.h> | 
 |  | 
 | #include <asm/dbell.h> | 
 | #include <asm/irq_regs.h> | 
 |  | 
 | #ifdef CONFIG_SMP | 
 | void doorbell_setup_this_cpu(void) | 
 | { | 
 | 	unsigned long tag = mfspr(SPRN_PIR) & 0x3fff; | 
 |  | 
 | 	smp_muxed_ipi_set_data(smp_processor_id(), tag); | 
 | } | 
 |  | 
 | void doorbell_cause_ipi(int cpu, unsigned long data) | 
 | { | 
 | 	/* Order previous accesses vs. msgsnd, which is treated as a store */ | 
 | 	mb(); | 
 | 	ppc_msgsnd(PPC_DBELL, 0, data); | 
 | } | 
 |  | 
 | void doorbell_exception(struct pt_regs *regs) | 
 | { | 
 | 	struct pt_regs *old_regs = set_irq_regs(regs); | 
 |  | 
 | 	irq_enter(); | 
 |  | 
 | 	may_hard_irq_enable(); | 
 |  | 
 | 	smp_ipi_demux(); | 
 |  | 
 | 	irq_exit(); | 
 | 	set_irq_regs(old_regs); | 
 | } | 
 | #else /* CONFIG_SMP */ | 
 | void doorbell_exception(struct pt_regs *regs) | 
 | { | 
 | 	printk(KERN_WARNING "Received doorbell on non-smp system\n"); | 
 | } | 
 | #endif /* CONFIG_SMP */ | 
 |  |