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
gsc_alloc_irq(struct gsc_irq * i)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
gsc_claim_irq(struct gsc_irq * i,int irq)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. */
gsc_asic_intr(int gsc_asic_irq,void * dev)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
gsc_find_local_irq(unsigned int irq,int * global_irqs,int limit)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
gsc_asic_mask_irq(struct irq_data * d)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
gsc_asic_unmask_irq(struct irq_data * d)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 static struct irq_chip gsc_asic_interrupt_type = {
139 .name = "GSC-ASIC",
140 .irq_unmask = gsc_asic_unmask_irq,
141 .irq_mask = gsc_asic_mask_irq,
142 };
143
gsc_assign_irq(struct irq_chip * type,void * data)144 int gsc_assign_irq(struct irq_chip *type, void *data)
145 {
146 static int irq = GSC_IRQ_BASE;
147
148 if (irq > GSC_IRQ_MAX)
149 return NO_IRQ;
150
151 irq_set_chip_and_handler(irq, type, handle_simple_irq);
152 irq_set_chip_data(irq, data);
153
154 return irq++;
155 }
156
gsc_asic_assign_irq(struct gsc_asic * asic,int local_irq,int * irqp)157 void gsc_asic_assign_irq(struct gsc_asic *asic, int local_irq, int *irqp)
158 {
159 int irq = asic->global_irq[local_irq];
160
161 if (irq <= 0) {
162 irq = gsc_assign_irq(&gsc_asic_interrupt_type, asic);
163 if (irq == NO_IRQ)
164 return;
165
166 asic->global_irq[local_irq] = irq;
167 }
168 *irqp = irq;
169 }
170
171 struct gsc_fixup_struct {
172 void (*choose_irq)(struct parisc_device *, void *);
173 void *ctrl;
174 };
175
gsc_fixup_irqs_callback(struct device * dev,void * data)176 static int gsc_fixup_irqs_callback(struct device *dev, void *data)
177 {
178 struct parisc_device *padev = to_parisc_device(dev);
179 struct gsc_fixup_struct *gf = data;
180
181 /* work-around for 715/64 and others which have parent
182 at path [5] and children at path [5/0/x] */
183 if (padev->id.hw_type == HPHW_FAULTY)
184 gsc_fixup_irqs(padev, gf->ctrl, gf->choose_irq);
185 gf->choose_irq(padev, gf->ctrl);
186
187 return 0;
188 }
189
gsc_fixup_irqs(struct parisc_device * parent,void * ctrl,void (* choose_irq)(struct parisc_device *,void *))190 void gsc_fixup_irqs(struct parisc_device *parent, void *ctrl,
191 void (*choose_irq)(struct parisc_device *, void *))
192 {
193 struct gsc_fixup_struct data = {
194 .choose_irq = choose_irq,
195 .ctrl = ctrl,
196 };
197
198 device_for_each_child(&parent->dev, &data, gsc_fixup_irqs_callback);
199 }
200
gsc_common_setup(struct parisc_device * parent,struct gsc_asic * gsc_asic)201 int gsc_common_setup(struct parisc_device *parent, struct gsc_asic *gsc_asic)
202 {
203 struct resource *res;
204 int i;
205
206 gsc_asic->gsc = parent;
207
208 /* Initialise local irq -> global irq mapping */
209 for (i = 0; i < 32; i++) {
210 gsc_asic->global_irq[i] = NO_IRQ;
211 }
212
213 /* allocate resource region */
214 res = request_mem_region(gsc_asic->hpa, 0x100000, gsc_asic->name);
215 if (res) {
216 res->flags = IORESOURCE_MEM; /* do not mark it busy ! */
217 }
218
219 #if 0
220 printk(KERN_WARNING "%s IRQ %d EIM 0x%x", gsc_asic->name,
221 parent->irq, gsc_asic->eim);
222 if (gsc_readl(gsc_asic->hpa + OFFSET_IMR))
223 printk(" IMR is non-zero! (0x%x)",
224 gsc_readl(gsc_asic->hpa + OFFSET_IMR));
225 printk("\n");
226 #endif
227
228 return 0;
229 }
230
231 extern struct parisc_driver lasi_driver;
232 extern struct parisc_driver asp_driver;
233 extern struct parisc_driver wax_driver;
234
gsc_init(void)235 void __init gsc_init(void)
236 {
237 #ifdef CONFIG_GSC_LASI
238 register_parisc_driver(&lasi_driver);
239 register_parisc_driver(&asp_driver);
240 #endif
241 #ifdef CONFIG_GSC_WAX
242 register_parisc_driver(&wax_driver);
243 #endif
244 }
245
