/* * Copyright 2010 PMC-Sierra, Inc, derived from irq_cpu.c * * This file define the irq handler for MSP PER subsystem interrupts. * * 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/init.h> #include <linux/interrupt.h> #include <linux/kernel.h> #include <linux/spinlock.h> #include <linux/bitops.h> #include <asm/mipsregs.h> #include <msp_cic_int.h> #include <msp_regs.h> /* * Convenience Macro. Should be somewhere generic. */ #define get_current_vpe() \ ((read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) & TCBIND_CURVPE) #ifdef CONFIG_SMP /* * The PER registers must be protected from concurrent access. */ static DEFINE_SPINLOCK(per_lock); #endif /* ensure writes to per are completed */ static inline void per_wmb(void) { const volatile void __iomem *per_mem = PER_INT_MSK_REG; volatile u32 dummy_read; wmb(); dummy_read = __raw_readl(per_mem); dummy_read++; } static inline void unmask_per_irq(struct irq_data *d) { #ifdef CONFIG_SMP unsigned long flags; spin_lock_irqsave(&per_lock, flags); *PER_INT_MSK_REG |= (1 << (d->irq - MSP_PER_INTBASE)); spin_unlock_irqrestore(&per_lock, flags); #else *PER_INT_MSK_REG |= (1 << (d->irq - MSP_PER_INTBASE)); #endif per_wmb(); } static inline void mask_per_irq(struct irq_data *d) { #ifdef CONFIG_SMP unsigned long flags; spin_lock_irqsave(&per_lock, flags); *PER_INT_MSK_REG &= ~(1 << (d->irq - MSP_PER_INTBASE)); spin_unlock_irqrestore(&per_lock, flags); #else *PER_INT_MSK_REG &= ~(1 << (d->irq - MSP_PER_INTBASE)); #endif per_wmb(); } static inline void msp_per_irq_ack(struct irq_data *d) { mask_per_irq(d); /* * In the PER interrupt controller, only bits 11 and 10 * are write-to-clear, (SPI TX complete, SPI RX complete). * It does nothing for any others. */ *PER_INT_STS_REG = (1 << (d->irq - MSP_PER_INTBASE)); } #ifdef CONFIG_SMP static int msp_per_irq_set_affinity(struct irq_data *d, const struct cpumask *affinity, bool force) { /* WTF is this doing ????? */ unmask_per_irq(d); return 0; } #endif static struct irq_chip msp_per_irq_controller = { .name = "MSP_PER", .irq_enable = unmask_per_irq, .irq_disable = mask_per_irq, .irq_ack = msp_per_irq_ack, #ifdef CONFIG_SMP .irq_set_affinity = msp_per_irq_set_affinity, #endif }; void __init msp_per_irq_init(void) { int i; /* Mask/clear interrupts. */ *PER_INT_MSK_REG = 0x00000000; *PER_INT_STS_REG = 0xFFFFFFFF; /* initialize all the IRQ descriptors */ for (i = MSP_PER_INTBASE; i < MSP_PER_INTBASE + 32; i++) { irq_set_chip(i, &msp_per_irq_controller); } } void msp_per_irq_dispatch(void) { u32 per_mask = *PER_INT_MSK_REG; u32 per_status = *PER_INT_STS_REG; u32 pending; pending = per_status & per_mask; if (pending) { do_IRQ(ffs(pending) + MSP_PER_INTBASE - 1); } else { spurious_interrupt(); } }