1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Interrupt management for most GSC and related devices. 4 * 5 * (c) Copyright 1999 Alex deVries for The Puffin Group 6 * (c) Copyright 1999 Grant Grundler for Hewlett-Packard 7 * (c) Copyright 1999 Matthew Wilcox 8 * (c) Copyright 2000 Helge Deller 9 * (c) Copyright 2001 Matthew Wilcox for Hewlett-Packard 10 */ 11 12 #include <linux/bitops.h> 13 #include <linux/errno.h> 14 #include <linux/init.h> 15 #include <linux/interrupt.h> 16 #include <linux/ioport.h> 17 #include <linux/module.h> 18 #include <linux/types.h> 19 20 #include <asm/hardware.h> 21 #include <asm/io.h> 22 23 #include "gsc.h" 24 25 #undef DEBUG 26 27 #ifdef DEBUG 28 #define DEBPRINTK printk 29 #else 30 #define DEBPRINTK(x,...) 31 #endif 32 33 int gsc_alloc_irq(struct gsc_irq *i) 34 { 35 int irq = txn_alloc_irq(GSC_EIM_WIDTH); 36 if (irq < 0) { 37 printk("cannot get irq\n"); 38 return irq; 39 } 40 41 i->txn_addr = txn_alloc_addr(irq); 42 i->txn_data = txn_alloc_data(irq); 43 i->irq = irq; 44 45 return irq; 46 } 47 48 int gsc_claim_irq(struct gsc_irq *i, int irq) 49 { 50 int c = irq; 51 52 irq += CPU_IRQ_BASE; /* virtualize the IRQ first */ 53 54 irq = txn_claim_irq(irq); 55 if (irq < 0) { 56 printk("cannot claim irq %d\n", c); 57 return irq; 58 } 59 60 i->txn_addr = txn_alloc_addr(irq); 61 i->txn_data = txn_alloc_data(irq); 62 i->irq = irq; 63 64 return irq; 65 } 66 67 EXPORT_SYMBOL(gsc_alloc_irq); 68 EXPORT_SYMBOL(gsc_claim_irq); 69 70 /* Common interrupt demultiplexer used by Asp, Lasi & Wax. */ 71 irqreturn_t gsc_asic_intr(int gsc_asic_irq, void *dev) 72 { 73 unsigned long irr; 74 struct gsc_asic *gsc_asic = dev; 75 76 irr = gsc_readl(gsc_asic->hpa + OFFSET_IRR); 77 if (irr == 0) 78 return IRQ_NONE; 79 80 DEBPRINTK("%s intr, mask=0x%x\n", gsc_asic->name, irr); 81 82 do { 83 int local_irq = __ffs(irr); 84 unsigned int irq = gsc_asic->global_irq[local_irq]; 85 generic_handle_irq(irq); 86 irr &= ~(1 << local_irq); 87 } while (irr); 88 89 return IRQ_HANDLED; 90 } 91 92 int gsc_find_local_irq(unsigned int irq, int *global_irqs, int limit) 93 { 94 int local_irq; 95 96 for (local_irq = 0; local_irq < limit; local_irq++) { 97 if (global_irqs[local_irq] == irq) 98 return local_irq; 99 } 100 101 return NO_IRQ; 102 } 103 104 static void gsc_asic_mask_irq(struct irq_data *d) 105 { 106 struct gsc_asic *irq_dev = irq_data_get_irq_chip_data(d); 107 int local_irq = gsc_find_local_irq(d->irq, irq_dev->global_irq, 32); 108 u32 imr; 109 110 DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, d->irq, 111 irq_dev->name, imr); 112 113 /* Disable the IRQ line by clearing the bit in the IMR */ 114 imr = gsc_readl(irq_dev->hpa + OFFSET_IMR); 115 imr &= ~(1 << local_irq); 116 gsc_writel(imr, irq_dev->hpa + OFFSET_IMR); 117 } 118 119 static void gsc_asic_unmask_irq(struct irq_data *d) 120 { 121 struct gsc_asic *irq_dev = irq_data_get_irq_chip_data(d); 122 int local_irq = gsc_find_local_irq(d->irq, irq_dev->global_irq, 32); 123 u32 imr; 124 125 DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, d->irq, 126 irq_dev->name, imr); 127 128 /* Enable the IRQ line by setting the bit in the IMR */ 129 imr = gsc_readl(irq_dev->hpa + OFFSET_IMR); 130 imr |= 1 << local_irq; 131 gsc_writel(imr, irq_dev->hpa + OFFSET_IMR); 132 /* 133 * FIXME: read IPR to make sure the IRQ isn't already pending. 134 * If so, we need to read IRR and manually call do_irq(). 135 */ 136 } 137 138 #ifdef CONFIG_SMP 139 static int gsc_set_affinity_irq(struct irq_data *d, const struct cpumask *dest, 140 bool force) 141 { 142 struct gsc_asic *gsc_dev = irq_data_get_irq_chip_data(d); 143 struct cpumask tmask; 144 int cpu_irq; 145 146 if (!cpumask_and(&tmask, dest, cpu_online_mask)) 147 return -EINVAL; 148 149 cpu_irq = cpu_check_affinity(d, &tmask); 150 if (cpu_irq < 0) 151 return cpu_irq; 152 153 gsc_dev->gsc_irq.txn_addr = txn_affinity_addr(d->irq, cpu_irq); 154 gsc_dev->eim = ((u32) gsc_dev->gsc_irq.txn_addr) | gsc_dev->gsc_irq.txn_data; 155 156 /* switch IRQ's for devices below LASI/WAX to other CPU */ 157 gsc_writel(gsc_dev->eim, gsc_dev->hpa + OFFSET_IAR); 158 159 irq_data_update_effective_affinity(d, &tmask); 160 161 return IRQ_SET_MASK_OK; 162 } 163 #endif 164 165 166 static struct irq_chip gsc_asic_interrupt_type = { 167 .name = "GSC-ASIC", 168 .irq_unmask = gsc_asic_unmask_irq, 169 .irq_mask = gsc_asic_mask_irq, 170 #ifdef CONFIG_SMP 171 .irq_set_affinity = gsc_set_affinity_irq, 172 #endif 173 }; 174 175 int gsc_assign_irq(struct irq_chip *type, void *data) 176 { 177 static int irq = GSC_IRQ_BASE; 178 179 if (irq > GSC_IRQ_MAX) 180 return NO_IRQ; 181 182 irq_set_chip_and_handler(irq, type, handle_simple_irq); 183 irq_set_chip_data(irq, data); 184 185 return irq++; 186 } 187 188 void gsc_asic_assign_irq(struct gsc_asic *asic, int local_irq, int *irqp) 189 { 190 int irq = asic->global_irq[local_irq]; 191 192 if (irq <= 0) { 193 irq = gsc_assign_irq(&gsc_asic_interrupt_type, asic); 194 if (irq == NO_IRQ) 195 return; 196 197 asic->global_irq[local_irq] = irq; 198 } 199 *irqp = irq; 200 } 201 202 struct gsc_fixup_struct { 203 void (*choose_irq)(struct parisc_device *, void *); 204 void *ctrl; 205 }; 206 207 static int gsc_fixup_irqs_callback(struct device *dev, void *data) 208 { 209 struct parisc_device *padev = to_parisc_device(dev); 210 struct gsc_fixup_struct *gf = data; 211 212 /* work-around for 715/64 and others which have parent 213 at path [5] and children at path [5/0/x] */ 214 if (padev->id.hw_type == HPHW_FAULTY) 215 gsc_fixup_irqs(padev, gf->ctrl, gf->choose_irq); 216 gf->choose_irq(padev, gf->ctrl); 217 218 return 0; 219 } 220 221 void gsc_fixup_irqs(struct parisc_device *parent, void *ctrl, 222 void (*choose_irq)(struct parisc_device *, void *)) 223 { 224 struct gsc_fixup_struct data = { 225 .choose_irq = choose_irq, 226 .ctrl = ctrl, 227 }; 228 229 device_for_each_child(&parent->dev, &data, gsc_fixup_irqs_callback); 230 } 231 232 int gsc_common_setup(struct parisc_device *parent, struct gsc_asic *gsc_asic) 233 { 234 struct resource *res; 235 int i; 236 237 gsc_asic->gsc = parent; 238 239 /* Initialise local irq -> global irq mapping */ 240 for (i = 0; i < 32; i++) { 241 gsc_asic->global_irq[i] = NO_IRQ; 242 } 243 244 /* allocate resource region */ 245 res = request_mem_region(gsc_asic->hpa, 0x100000, gsc_asic->name); 246 if (res) { 247 res->flags = IORESOURCE_MEM; /* do not mark it busy ! */ 248 } 249 250 #if 0 251 printk(KERN_WARNING "%s IRQ %d EIM 0x%x", gsc_asic->name, 252 parent->irq, gsc_asic->eim); 253 if (gsc_readl(gsc_asic->hpa + OFFSET_IMR)) 254 printk(" IMR is non-zero! (0x%x)", 255 gsc_readl(gsc_asic->hpa + OFFSET_IMR)); 256 printk("\n"); 257 #endif 258 259 return 0; 260 } 261