1 /* 2 * Copyright (C) 2002 ARM Limited, All Rights Reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 17 #include <linux/interrupt.h> 18 #include <linux/io.h> 19 #include <linux/irq.h> 20 #include <linux/irqchip/arm-gic.h> 21 22 #include "irq-gic-common.h" 23 24 void gic_configure_irq(unsigned int irq, unsigned int type, 25 void __iomem *base, void (*sync_access)(void)) 26 { 27 u32 enablemask = 1 << (irq % 32); 28 u32 enableoff = (irq / 32) * 4; 29 u32 confmask = 0x2 << ((irq % 16) * 2); 30 u32 confoff = (irq / 16) * 4; 31 bool enabled = false; 32 u32 val; 33 34 /* 35 * Read current configuration register, and insert the config 36 * for "irq", depending on "type". 37 */ 38 val = readl_relaxed(base + GIC_DIST_CONFIG + confoff); 39 if (type == IRQ_TYPE_LEVEL_HIGH) 40 val &= ~confmask; 41 else if (type == IRQ_TYPE_EDGE_RISING) 42 val |= confmask; 43 44 /* 45 * As recommended by the spec, disable the interrupt before changing 46 * the configuration 47 */ 48 if (readl_relaxed(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) { 49 writel_relaxed(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff); 50 if (sync_access) 51 sync_access(); 52 enabled = true; 53 } 54 55 /* 56 * Write back the new configuration, and possibly re-enable 57 * the interrupt. 58 */ 59 writel_relaxed(val, base + GIC_DIST_CONFIG + confoff); 60 61 if (enabled) 62 writel_relaxed(enablemask, base + GIC_DIST_ENABLE_SET + enableoff); 63 64 if (sync_access) 65 sync_access(); 66 } 67 68 void __init gic_dist_config(void __iomem *base, int gic_irqs, 69 void (*sync_access)(void)) 70 { 71 unsigned int i; 72 73 /* 74 * Set all global interrupts to be level triggered, active low. 75 */ 76 for (i = 32; i < gic_irqs; i += 16) 77 writel_relaxed(0, base + GIC_DIST_CONFIG + i / 4); 78 79 /* 80 * Set priority on all global interrupts. 81 */ 82 for (i = 32; i < gic_irqs; i += 4) 83 writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i); 84 85 /* 86 * Disable all interrupts. Leave the PPI and SGIs alone 87 * as they are enabled by redistributor registers. 88 */ 89 for (i = 32; i < gic_irqs; i += 32) 90 writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i / 8); 91 92 if (sync_access) 93 sync_access(); 94 } 95 96 void gic_cpu_config(void __iomem *base, void (*sync_access)(void)) 97 { 98 int i; 99 100 /* 101 * Deal with the banked PPI and SGI interrupts - disable all 102 * PPI interrupts, ensure all SGI interrupts are enabled. 103 */ 104 writel_relaxed(0xffff0000, base + GIC_DIST_ENABLE_CLEAR); 105 writel_relaxed(0x0000ffff, base + GIC_DIST_ENABLE_SET); 106 107 /* 108 * Set priority on PPI and SGI interrupts 109 */ 110 for (i = 0; i < 32; i += 4) 111 writel_relaxed(0xa0a0a0a0, base + GIC_DIST_PRI + i * 4 / 4); 112 113 if (sync_access) 114 sync_access(); 115 } 116