xref: /linux/drivers/parisc/gsc.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
1 /*
2  * Interrupt management for most GSC and related devices.
3  *
4  * (c) Copyright 1999 Alex deVries for The Puffin Group
5  * (c) Copyright 1999 Grant Grundler for Hewlett-Packard
6  * (c) Copyright 1999 Matthew Wilcox
7  * (c) Copyright 2000 Helge Deller
8  * (c) Copyright 2001 Matthew Wilcox for Hewlett-Packard
9  *
10  *	This program is free software; you can redistribute it and/or modify
11  *	it under the terms of the GNU General Public License as published by
12  *      the Free Software Foundation; either version 2 of the License, or
13  *      (at your option) any later version.
14  */
15 
16 #include <linux/bitops.h>
17 #include <linux/errno.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/ioport.h>
21 #include <linux/module.h>
22 #include <linux/types.h>
23 
24 #include <asm/hardware.h>
25 #include <asm/io.h>
26 
27 #include "gsc.h"
28 
29 #undef DEBUG
30 
31 #ifdef DEBUG
32 #define DEBPRINTK printk
33 #else
34 #define DEBPRINTK(x,...)
35 #endif
36 
37 int gsc_alloc_irq(struct gsc_irq *i)
38 {
39 	int irq = txn_alloc_irq(GSC_EIM_WIDTH);
40 	if (irq < 0) {
41 		printk("cannot get irq\n");
42 		return irq;
43 	}
44 
45 	i->txn_addr = txn_alloc_addr(irq);
46 	i->txn_data = txn_alloc_data(irq);
47 	i->irq = irq;
48 
49 	return irq;
50 }
51 
52 int gsc_claim_irq(struct gsc_irq *i, int irq)
53 {
54 	int c = irq;
55 
56 	irq += CPU_IRQ_BASE; /* virtualize the IRQ first */
57 
58 	irq = txn_claim_irq(irq);
59 	if (irq < 0) {
60 		printk("cannot claim irq %d\n", c);
61 		return irq;
62 	}
63 
64 	i->txn_addr = txn_alloc_addr(irq);
65 	i->txn_data = txn_alloc_data(irq);
66 	i->irq = irq;
67 
68 	return irq;
69 }
70 
71 EXPORT_SYMBOL(gsc_alloc_irq);
72 EXPORT_SYMBOL(gsc_claim_irq);
73 
74 /* Common interrupt demultiplexer used by Asp, Lasi & Wax.  */
75 irqreturn_t gsc_asic_intr(int gsc_asic_irq, void *dev)
76 {
77 	unsigned long irr;
78 	struct gsc_asic *gsc_asic = dev;
79 
80 	irr = gsc_readl(gsc_asic->hpa + OFFSET_IRR);
81 	if (irr == 0)
82 		return IRQ_NONE;
83 
84 	DEBPRINTK("%s intr, mask=0x%x\n", gsc_asic->name, irr);
85 
86 	do {
87 		int local_irq = __ffs(irr);
88 		unsigned int irq = gsc_asic->global_irq[local_irq];
89 		__do_IRQ(irq);
90 		irr &= ~(1 << local_irq);
91 	} while (irr);
92 
93 	return IRQ_HANDLED;
94 }
95 
96 int gsc_find_local_irq(unsigned int irq, int *global_irqs, int limit)
97 {
98 	int local_irq;
99 
100 	for (local_irq = 0; local_irq < limit; local_irq++) {
101 		if (global_irqs[local_irq] == irq)
102 			return local_irq;
103 	}
104 
105 	return NO_IRQ;
106 }
107 
108 static void gsc_asic_disable_irq(unsigned int irq)
109 {
110 	struct irq_desc *desc = irq_to_desc(irq);
111 	struct gsc_asic *irq_dev = desc->chip_data;
112 	int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
113 	u32 imr;
114 
115 	DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, irq,
116 			irq_dev->name, imr);
117 
118 	/* Disable the IRQ line by clearing the bit in the IMR */
119 	imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
120 	imr &= ~(1 << local_irq);
121 	gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
122 }
123 
124 static void gsc_asic_enable_irq(unsigned int irq)
125 {
126 	struct irq_desc *desc = irq_to_desc(irq);
127 	struct gsc_asic *irq_dev = desc->chip_data;
128 	int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
129 	u32 imr;
130 
131 	DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __func__, irq,
132 			irq_dev->name, imr);
133 
134 	/* Enable the IRQ line by setting the bit in the IMR */
135 	imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
136 	imr |= 1 << local_irq;
137 	gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
138 	/*
139 	 * FIXME: read IPR to make sure the IRQ isn't already pending.
140 	 *   If so, we need to read IRR and manually call do_irq().
141 	 */
142 }
143 
144 static unsigned int gsc_asic_startup_irq(unsigned int irq)
145 {
146 	gsc_asic_enable_irq(irq);
147 	return 0;
148 }
149 
150 static struct irq_chip gsc_asic_interrupt_type = {
151 	.name	 =	"GSC-ASIC",
152 	.startup =	gsc_asic_startup_irq,
153 	.shutdown =	gsc_asic_disable_irq,
154 	.enable =	gsc_asic_enable_irq,
155 	.disable =	gsc_asic_disable_irq,
156 	.ack =		no_ack_irq,
157 	.end =		no_end_irq,
158 };
159 
160 int gsc_assign_irq(struct irq_chip *type, void *data)
161 {
162 	static int irq = GSC_IRQ_BASE;
163 	struct irq_desc *desc;
164 
165 	if (irq > GSC_IRQ_MAX)
166 		return NO_IRQ;
167 
168 	desc = irq_to_desc(irq);
169 	desc->chip = type;
170 	desc->chip_data = data;
171 	return irq++;
172 }
173 
174 void gsc_asic_assign_irq(struct gsc_asic *asic, int local_irq, int *irqp)
175 {
176 	int irq = asic->global_irq[local_irq];
177 
178 	if (irq <= 0) {
179 		irq = gsc_assign_irq(&gsc_asic_interrupt_type, asic);
180 		if (irq == NO_IRQ)
181 			return;
182 
183 		asic->global_irq[local_irq] = irq;
184 	}
185 	*irqp = irq;
186 }
187 
188 struct gsc_fixup_struct {
189 	void (*choose_irq)(struct parisc_device *, void *);
190 	void *ctrl;
191 };
192 
193 static int gsc_fixup_irqs_callback(struct device *dev, void *data)
194 {
195 	struct parisc_device *padev = to_parisc_device(dev);
196 	struct gsc_fixup_struct *gf = data;
197 
198 	/* work-around for 715/64 and others which have parent
199 	   at path [5] and children at path [5/0/x] */
200 	if (padev->id.hw_type == HPHW_FAULTY)
201 		gsc_fixup_irqs(padev, gf->ctrl, gf->choose_irq);
202 	gf->choose_irq(padev, gf->ctrl);
203 
204 	return 0;
205 }
206 
207 void gsc_fixup_irqs(struct parisc_device *parent, void *ctrl,
208 			void (*choose_irq)(struct parisc_device *, void *))
209 {
210 	struct gsc_fixup_struct data = {
211 		.choose_irq	= choose_irq,
212 		.ctrl		= ctrl,
213 	};
214 
215 	device_for_each_child(&parent->dev, &data, gsc_fixup_irqs_callback);
216 }
217 
218 int gsc_common_setup(struct parisc_device *parent, struct gsc_asic *gsc_asic)
219 {
220 	struct resource *res;
221 	int i;
222 
223 	gsc_asic->gsc = parent;
224 
225 	/* Initialise local irq -> global irq mapping */
226 	for (i = 0; i < 32; i++) {
227 		gsc_asic->global_irq[i] = NO_IRQ;
228 	}
229 
230 	/* allocate resource region */
231 	res = request_mem_region(gsc_asic->hpa, 0x100000, gsc_asic->name);
232 	if (res) {
233 		res->flags = IORESOURCE_MEM; 	/* do not mark it busy ! */
234 	}
235 
236 #if 0
237 	printk(KERN_WARNING "%s IRQ %d EIM 0x%x", gsc_asic->name,
238 			parent->irq, gsc_asic->eim);
239 	if (gsc_readl(gsc_asic->hpa + OFFSET_IMR))
240 		printk("  IMR is non-zero! (0x%x)",
241 				gsc_readl(gsc_asic->hpa + OFFSET_IMR));
242 	printk("\n");
243 #endif
244 
245 	return 0;
246 }
247 
248 extern struct parisc_driver lasi_driver;
249 extern struct parisc_driver asp_driver;
250 extern struct parisc_driver wax_driver;
251 
252 void __init gsc_init(void)
253 {
254 #ifdef CONFIG_GSC_LASI
255 	register_parisc_driver(&lasi_driver);
256 	register_parisc_driver(&asp_driver);
257 #endif
258 #ifdef CONFIG_GSC_WAX
259 	register_parisc_driver(&wax_driver);
260 #endif
261 }
262