1 /* 2 * GT641xx IRQ routines. 3 * 4 * Copyright (C) 2007 Yoichi Yuasa <yuasa@linux-mips.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 #include <linux/hardirq.h> 21 #include <linux/init.h> 22 #include <linux/irq.h> 23 #include <linux/spinlock.h> 24 #include <linux/types.h> 25 26 #include <asm/gt64120.h> 27 28 #define GT641XX_IRQ_TO_BIT(irq) (1U << (irq - GT641XX_IRQ_BASE)) 29 30 static DEFINE_RAW_SPINLOCK(gt641xx_irq_lock); 31 32 static void ack_gt641xx_irq(struct irq_data *d) 33 { 34 unsigned long flags; 35 u32 cause; 36 37 raw_spin_lock_irqsave(>641xx_irq_lock, flags); 38 cause = GT_READ(GT_INTRCAUSE_OFS); 39 cause &= ~GT641XX_IRQ_TO_BIT(d->irq); 40 GT_WRITE(GT_INTRCAUSE_OFS, cause); 41 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags); 42 } 43 44 static void mask_gt641xx_irq(struct irq_data *d) 45 { 46 unsigned long flags; 47 u32 mask; 48 49 raw_spin_lock_irqsave(>641xx_irq_lock, flags); 50 mask = GT_READ(GT_INTRMASK_OFS); 51 mask &= ~GT641XX_IRQ_TO_BIT(d->irq); 52 GT_WRITE(GT_INTRMASK_OFS, mask); 53 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags); 54 } 55 56 static void mask_ack_gt641xx_irq(struct irq_data *d) 57 { 58 unsigned long flags; 59 u32 cause, mask; 60 61 raw_spin_lock_irqsave(>641xx_irq_lock, flags); 62 mask = GT_READ(GT_INTRMASK_OFS); 63 mask &= ~GT641XX_IRQ_TO_BIT(d->irq); 64 GT_WRITE(GT_INTRMASK_OFS, mask); 65 66 cause = GT_READ(GT_INTRCAUSE_OFS); 67 cause &= ~GT641XX_IRQ_TO_BIT(d->irq); 68 GT_WRITE(GT_INTRCAUSE_OFS, cause); 69 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags); 70 } 71 72 static void unmask_gt641xx_irq(struct irq_data *d) 73 { 74 unsigned long flags; 75 u32 mask; 76 77 raw_spin_lock_irqsave(>641xx_irq_lock, flags); 78 mask = GT_READ(GT_INTRMASK_OFS); 79 mask |= GT641XX_IRQ_TO_BIT(d->irq); 80 GT_WRITE(GT_INTRMASK_OFS, mask); 81 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags); 82 } 83 84 static struct irq_chip gt641xx_irq_chip = { 85 .name = "GT641xx", 86 .irq_ack = ack_gt641xx_irq, 87 .irq_mask = mask_gt641xx_irq, 88 .irq_mask_ack = mask_ack_gt641xx_irq, 89 .irq_unmask = unmask_gt641xx_irq, 90 }; 91 92 void gt641xx_irq_dispatch(void) 93 { 94 u32 cause, mask; 95 int i; 96 97 cause = GT_READ(GT_INTRCAUSE_OFS); 98 mask = GT_READ(GT_INTRMASK_OFS); 99 cause &= mask; 100 101 /* 102 * bit0 : logical or of all the interrupt bits. 103 * bit30: logical or of bits[29:26,20:1]. 104 * bit31: logical or of bits[25:1]. 105 */ 106 for (i = 1; i < 30; i++) { 107 if (cause & (1U << i)) { 108 do_IRQ(GT641XX_IRQ_BASE + i); 109 return; 110 } 111 } 112 113 atomic_inc(&irq_err_count); 114 } 115 116 void __init gt641xx_irq_init(void) 117 { 118 int i; 119 120 GT_WRITE(GT_INTRMASK_OFS, 0); 121 GT_WRITE(GT_INTRCAUSE_OFS, 0); 122 123 /* 124 * bit0 : logical or of all the interrupt bits. 125 * bit30: logical or of bits[29:26,20:1]. 126 * bit31: logical or of bits[25:1]. 127 */ 128 for (i = 1; i < 30; i++) 129 irq_set_chip_and_handler(GT641XX_IRQ_BASE + i, 130 >641xx_irq_chip, handle_level_irq); 131 } 132