1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Author: Kumar Gala <galak@kernel.crashing.org> 4 * 5 * Copyright 2009 Freescale Semiconductor Inc. 6 */ 7 8 #include <linux/stddef.h> 9 #include <linux/kernel.h> 10 #include <linux/smp.h> 11 #include <linux/threads.h> 12 #include <linux/hardirq.h> 13 14 #include <asm/dbell.h> 15 #include <asm/irq_regs.h> 16 #include <asm/kvm_ppc.h> 17 #include <asm/trace.h> 18 19 #ifdef CONFIG_SMP 20 21 void doorbell_exception(struct pt_regs *regs) 22 { 23 struct pt_regs *old_regs = set_irq_regs(regs); 24 25 irq_enter(); 26 trace_doorbell_entry(regs); 27 28 ppc_msgsync(); 29 30 may_hard_irq_enable(); 31 32 kvmppc_clear_host_ipi(smp_processor_id()); 33 __this_cpu_inc(irq_stat.doorbell_irqs); 34 35 smp_ipi_demux_relaxed(); /* already performed the barrier */ 36 37 trace_doorbell_exit(regs); 38 irq_exit(); 39 set_irq_regs(old_regs); 40 } 41 #else /* CONFIG_SMP */ 42 void doorbell_exception(struct pt_regs *regs) 43 { 44 printk(KERN_WARNING "Received doorbell on non-smp system\n"); 45 } 46 #endif /* CONFIG_SMP */ 47 48