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_enable_quirks(u32 iidr, const struct gic_quirk *quirks, 25 void *data) 26 { 27 for (; quirks->desc; quirks++) { 28 if (quirks->iidr != (quirks->mask & iidr)) 29 continue; 30 quirks->init(data); 31 pr_info("GIC: enabling workaround for %s\n", quirks->desc); 32 } 33 } 34 35 int gic_configure_irq(unsigned int irq, unsigned int type, 36 void __iomem *base, void (*sync_access)(void)) 37 { 38 u32 confmask = 0x2 << ((irq % 16) * 2); 39 u32 confoff = (irq / 16) * 4; 40 u32 val, oldval; 41 int ret = 0; 42 43 /* 44 * Read current configuration register, and insert the config 45 * for "irq", depending on "type". 46 */ 47 val = oldval = readl_relaxed(base + GIC_DIST_CONFIG + confoff); 48 if (type & IRQ_TYPE_LEVEL_MASK) 49 val &= ~confmask; 50 else if (type & IRQ_TYPE_EDGE_BOTH) 51 val |= confmask; 52 53 /* 54 * Write back the new configuration, and possibly re-enable 55 * the interrupt. If we tried to write a new configuration and failed, 56 * return an error. 57 */ 58 writel_relaxed(val, base + GIC_DIST_CONFIG + confoff); 59 if (readl_relaxed(base + GIC_DIST_CONFIG + confoff) != val && val != oldval) 60 ret = -EINVAL; 61 62 if (sync_access) 63 sync_access(); 64 65 return ret; 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(GICD_INT_ACTLOW_LVLTRIG, 78 base + GIC_DIST_CONFIG + i / 4); 79 80 /* 81 * Set priority on all global interrupts. 82 */ 83 for (i = 32; i < gic_irqs; i += 4) 84 writel_relaxed(GICD_INT_DEF_PRI_X4, base + GIC_DIST_PRI + i); 85 86 /* 87 * Disable all interrupts. Leave the PPI and SGIs alone 88 * as they are enabled by redistributor registers. 89 */ 90 for (i = 32; i < gic_irqs; i += 32) 91 writel_relaxed(GICD_INT_EN_CLR_X32, 92 base + GIC_DIST_ENABLE_CLEAR + i / 8); 93 94 if (sync_access) 95 sync_access(); 96 } 97 98 void gic_cpu_config(void __iomem *base, void (*sync_access)(void)) 99 { 100 int i; 101 102 /* 103 * Deal with the banked PPI and SGI interrupts - disable all 104 * PPI interrupts, ensure all SGI interrupts are enabled. 105 */ 106 writel_relaxed(GICD_INT_EN_CLR_PPI, base + GIC_DIST_ENABLE_CLEAR); 107 writel_relaxed(GICD_INT_EN_SET_SGI, base + GIC_DIST_ENABLE_SET); 108 109 /* 110 * Set priority on PPI and SGI interrupts 111 */ 112 for (i = 0; i < 32; i += 4) 113 writel_relaxed(GICD_INT_DEF_PRI_X4, 114 base + GIC_DIST_PRI + i * 4 / 4); 115 116 if (sync_access) 117 sync_access(); 118 } 119