aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/platforms/cell/interrupt.c
blob: 9d5da7896892701baa4fd85ea2b0a27b8be26c0c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
/*
 * Cell Internal Interrupt Controller
 *
 * Copyright (C) 2006 Benjamin Herrenschmidt (benh@kernel.crashing.org)
 *                    IBM, Corp.
 *
 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
 *
 * Author: Arnd Bergmann <arndb@de.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/percpu.h>
#include <linux/types.h>
#include <linux/ioport.h>

#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/prom.h>
#include <asm/ptrace.h>
#include <asm/machdep.h>

#include "interrupt.h"
#include "cbe_regs.h"

struct iic {
	struct cbe_iic_thread_regs __iomem *regs;
	u8 target_id;
	u8 eoi_stack[16];
	int eoi_ptr;
	struct irq_host *host;
};

static DEFINE_PER_CPU(struct iic, iic);
#define IIC_NODE_COUNT	2
static struct irq_host *iic_hosts[IIC_NODE_COUNT];

/* Convert between "pending" bits and hw irq number */
static irq_hw_number_t iic_pending_to_hwnum(struct cbe_iic_pending_bits bits)
{
	unsigned char unit = bits.source & 0xf;

	if (bits.flags & CBE_IIC_IRQ_IPI)
		return IIC_IRQ_IPI0 | (bits.prio >> 4);
	else if (bits.class <= 3)
		return (bits.class << 4) | unit;
	else
		return IIC_IRQ_INVALID;
}

static void iic_mask(unsigned int irq)
{
}

static void iic_unmask(unsigned int irq)
{
}

static void iic_eoi(unsigned int irq)
{
	struct iic *iic = &__get_cpu_var(iic);
	out_be64(&iic->regs->prio, iic->eoi_stack[--iic->eoi_ptr]);
	BUG_ON(iic->eoi_ptr < 0);
}

static struct irq_chip iic_chip = {
	.typename = " CELL-IIC ",
	.mask = iic_mask,
	.unmask = iic_unmask,
	.eoi = iic_eoi,
};

/* Get an IRQ number from the pending state register of the IIC */
static unsigned int iic_get_irq(struct pt_regs *regs)
{
  	struct cbe_iic_pending_bits pending;
 	struct iic *iic;

 	iic = &__get_cpu_var(iic);
 	*(unsigned long *) &pending =
 		in_be64((unsigned long __iomem *) &iic->regs->pending_destr);
 	iic->eoi_stack[++iic->eoi_ptr] = pending.prio;
 	BUG_ON(iic->eoi_ptr > 15);
	if (pending.flags & CBE_IIC_IRQ_VALID)
		return irq_linear_revmap(iic->host,
 					 iic_pending_to_hwnum(pending));
	return NO_IRQ;
}

#ifdef CONFIG_SMP

/* Use the highest interrupt priorities for IPI */
static inline int iic_ipi_to_irq(int ipi)
{
	return IIC_IRQ_IPI0 + IIC_NUM_IPIS - 1 - ipi;
}

static inline int iic_irq_to_ipi(int irq)
{
	return IIC_NUM_IPIS - 1 - (irq - IIC_IRQ_IPI0);
}

void iic_setup_cpu(void)
{
	out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
}

void iic_cause_IPI(int cpu, int mesg)
{
	out_be64(&per_cpu(iic, cpu).regs->generate, (IIC_NUM_IPIS - 1 - mesg) << 4);
}

u8 iic_get_target_id(int cpu)
{
	return per_cpu(iic, cpu).target_id;
}
EXPORT_SYMBOL_GPL(iic_get_target_id);

struct irq_host *iic_get_irq_host(int node)
{
	if (node < 0 || node >= IIC_NODE_COUNT)
		return NULL;
	return iic_hosts[node];
}
EXPORT_SYMBOL_GPL(iic_get_irq_host);


static irqreturn_t iic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
{
	int ipi = (int)(long)dev_id;

	smp_message_recv(ipi, regs);

	return IRQ_HANDLED;
}

static void iic_request_ipi(int ipi, const char *name)
{
	int node, virq;

	for (node = 0; node < IIC_NODE_COUNT; node++) {
		char *rname;
		if (iic_hosts[node] == NULL)
			continue;
		virq = irq_create_mapping(iic_hosts[node],
					  iic_ipi_to_irq(ipi), 0);
		if (virq == NO_IRQ) {
			printk(KERN_ERR
			       "iic: failed to map IPI %s on node %d\n",
			       name, node);
			continue;
		}
		rname = kzalloc(strlen(name) + 16, GFP_KERNEL);
		if (rname)
			sprintf(rname, "%s node %d", name, node);
		else
			rname = (char *)name;
		if (request_irq(virq, iic_ipi_action, IRQF_DISABLED,
				rname, (void *)(long)ipi))
			printk(KERN_ERR
			       "iic: failed to request IPI %s on node %d\n",
			       name, node);
	}
}

void iic_request_IPIs(void)
{
	iic_request_ipi(PPC_MSG_CALL_FUNCTION, "IPI-call");
	iic_request_ipi(PPC_MSG_RESCHEDULE, "IPI-resched");
#ifdef CONFIG_DEBUGGER
	iic_request_ipi(PPC_MSG_DEBUGGER_BREAK, "IPI-debug");
#endif /* CONFIG_DEBUGGER */
}

#endif /* CONFIG_SMP */


static int iic_host_match(struct irq_host *h, struct device_node *node)
{
	return h->host_data != NULL && node == h->host_data;
}

static int iic_host_map(struct irq_host *h, unsigned int virq,
			irq_hw_number_t hw, unsigned int flags)
{
	if (hw < IIC_IRQ_IPI0)
		set_irq_chip_and_handler(virq, &iic_chip, handle_fasteoi_irq);
	else
		set_irq_chip_and_handler(virq, &iic_chip, handle_percpu_irq);
	return 0;
}

static int iic_host_xlate(struct irq_host *h, struct device_node *ct,
			   u32 *intspec, unsigned int intsize,
			   irq_hw_number_t *out_hwirq, unsigned int *out_flags)

{
	/* Currently, we don't translate anything. That needs to be fixed as
	 * we get better defined device-trees. iic interrupts have to be
	 * explicitely mapped by whoever needs them
	 */
	return -ENODEV;
}

static struct irq_host_ops iic_host_ops = {
	.match = iic_host_match,
	.map = iic_host_map,
	.xlate = iic_host_xlate,
};

static void __init init_one_iic(unsigned int hw_cpu, unsigned long addr,
				struct irq_host *host)
{
	/* XXX FIXME: should locate the linux CPU number from the HW cpu
	 * number properly. We are lucky for now
	 */
	struct iic *iic = &per_cpu(iic, hw_cpu);

	iic->regs = ioremap(addr, sizeof(struct cbe_iic_thread_regs));
	BUG_ON(iic->regs == NULL);

	iic->target_id = ((hw_cpu & 2) << 3) | ((hw_cpu & 1) ? 0xf : 0xe);
	iic->eoi_stack[0] = 0xff;
	iic->host = host;
	out_be64(&iic->regs->prio, 0);

	printk(KERN_INFO "IIC for CPU %d at %lx mapped to %p, target id 0x%x\n",
	       hw_cpu, addr, iic->regs, iic->target_id);
}

static int __init setup_iic(void)
{
	struct device_node *dn;
	struct resource r0, r1;
	struct irq_host *host;
	int found = 0;
 	u32 *np;

	for (dn = NULL;
	     (dn = of_find_node_by_name(dn,"interrupt-controller")) != NULL;) {
		if (!device_is_compatible(dn,
				     "IBM,CBEA-Internal-Interrupt-Controller"))
			continue;
 		np = (u32 *)get_property(dn, "ibm,interrupt-server-ranges",
					 NULL);
 		if (np == NULL) {
			printk(KERN_WARNING "IIC: CPU association not found\n");
			of_node_put(dn);
			return -ENODEV;
		}
		if (of_address_to_resource(dn, 0, &r0) ||
		    of_address_to_resource(dn, 1, &r1)) {
			printk(KERN_WARNING "IIC: Can't resolve addresses\n");
			of_node_put(dn);
			return -ENODEV;
		}
		host = NULL;
		if (found < IIC_NODE_COUNT) {
			host = irq_alloc_host(IRQ_HOST_MAP_LINEAR,
					      IIC_SOURCE_COUNT,
					      &iic_host_ops,
					      IIC_IRQ_INVALID);
			iic_hosts[found] = host;
			BUG_ON(iic_hosts[found] == NULL);
			iic_hosts[found]->host_data = of_node_get(dn);
			found++;
		}
		init_one_iic(np[0], r0.start, host);
		init_one_iic(np[1], r1.start, host);
	}

	if (found)
		return 0;
	else
		return -ENODEV;
}

void __init iic_init_IRQ(void)
{
	/* Discover and initialize iics */
	if (setup_iic() < 0)
		panic("IIC: Failed to initialize !\n");

	/* Set master interrupt handling function */
	ppc_md.get_irq = iic_get_irq;

	/* Enable on current CPU */
	iic_setup_cpu();
}

Privacy Policy