/* * Author: Kumar Gala * * 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 #include #include #include #include #include #include #include #ifdef CONFIG_SMP /* * Doorbells must only be used if CPU_FTR_DBELL is available. * msgsnd is used in HV, and msgsndp is used in !HV. * * These should be used by platform code that is aware of restrictions. * Other arch code should use ->cause_ipi. * * doorbell_global_ipi() sends a dbell to any target CPU. * Must be used only by architectures that address msgsnd target * by PIR/get_hard_smp_processor_id. */ void doorbell_global_ipi(int cpu) { u32 tag = get_hard_smp_processor_id(cpu); kvmppc_set_host_ipi(cpu, 1); /* Order previous accesses vs. msgsnd, which is treated as a store */ mb(); ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, tag); } /* * doorbell_core_ipi() sends a dbell to a target CPU in the same core. * Must be used only by architectures that address msgsnd target * by TIR/cpu_thread_in_core. */ void doorbell_core_ipi(int cpu) { u32 tag = cpu_thread_in_core(cpu); kvmppc_set_host_ipi(cpu, 1); /* Order previous accesses vs. msgsnd, which is treated as a store */ mb(); ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, tag); } /* * Attempt to cause a core doorbell if destination is on the same core. * Returns 1 on success, 0 on failure. */ int doorbell_try_core_ipi(int cpu) { int this_cpu = get_cpu(); int ret = 0; if (cpumask_test_cpu(cpu, cpu_sibling_mask(this_cpu))) { doorbell_core_ipi(cpu); ret = 1; } put_cpu(); return ret; } void doorbell_exception(struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); irq_enter(); may_hard_irq_enable(); kvmppc_set_host_ipi(smp_processor_id(), 0); __this_cpu_inc(irq_stat.doorbell_irqs); 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 */