[POWERPC] Add new interrupt mapping core and change platforms to use it
[linux-2.6.git] / arch / powerpc / platforms / cell / interrupt.c
1 /*
2  * Cell Internal Interrupt Controller
3  *
4  * Copyright (C) 2006 Benjamin Herrenschmidt (benh@kernel.crashing.org)
5  *                    IBM, Corp.
6  *
7  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
8  *
9  * Author: Arnd Bergmann <arndb@de.ibm.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2, or (at your option)
14  * any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25
26 #include <linux/interrupt.h>
27 #include <linux/irq.h>
28 #include <linux/module.h>
29 #include <linux/percpu.h>
30 #include <linux/types.h>
31 #include <linux/ioport.h>
32
33 #include <asm/io.h>
34 #include <asm/pgtable.h>
35 #include <asm/prom.h>
36 #include <asm/ptrace.h>
37 #include <asm/machdep.h>
38
39 #include "interrupt.h"
40 #include "cbe_regs.h"
41
42 struct iic {
43         struct cbe_iic_thread_regs __iomem *regs;
44         u8 target_id;
45         u8 eoi_stack[16];
46         int eoi_ptr;
47         struct irq_host *host;
48 };
49
50 static DEFINE_PER_CPU(struct iic, iic);
51 #define IIC_NODE_COUNT  2
52 static struct irq_host *iic_hosts[IIC_NODE_COUNT];
53
54 /* Convert between "pending" bits and hw irq number */
55 static irq_hw_number_t iic_pending_to_hwnum(struct cbe_iic_pending_bits bits)
56 {
57         unsigned char unit = bits.source & 0xf;
58
59         if (bits.flags & CBE_IIC_IRQ_IPI)
60                 return IIC_IRQ_IPI0 | (bits.prio >> 4);
61         else if (bits.class <= 3)
62                 return (bits.class << 4) | unit;
63         else
64                 return IIC_IRQ_INVALID;
65 }
66
67 static void iic_mask(unsigned int irq)
68 {
69 }
70
71 static void iic_unmask(unsigned int irq)
72 {
73 }
74
75 static void iic_eoi(unsigned int irq)
76 {
77         struct iic *iic = &__get_cpu_var(iic);
78         out_be64(&iic->regs->prio, iic->eoi_stack[--iic->eoi_ptr]);
79         BUG_ON(iic->eoi_ptr < 0);
80 }
81
82 static struct irq_chip iic_chip = {
83         .typename = " CELL-IIC ",
84         .mask = iic_mask,
85         .unmask = iic_unmask,
86         .eoi = iic_eoi,
87 };
88
89 /* Get an IRQ number from the pending state register of the IIC */
90 static unsigned int iic_get_irq(struct pt_regs *regs)
91 {
92         struct cbe_iic_pending_bits pending;
93         struct iic *iic;
94
95         iic = &__get_cpu_var(iic);
96         *(unsigned long *) &pending =
97                 in_be64((unsigned long __iomem *) &iic->regs->pending_destr);
98         iic->eoi_stack[++iic->eoi_ptr] = pending.prio;
99         BUG_ON(iic->eoi_ptr > 15);
100         if (pending.flags & CBE_IIC_IRQ_VALID)
101                 return irq_linear_revmap(iic->host,
102                                          iic_pending_to_hwnum(pending));
103         return NO_IRQ;
104 }
105
106 #ifdef CONFIG_SMP
107
108 /* Use the highest interrupt priorities for IPI */
109 static inline int iic_ipi_to_irq(int ipi)
110 {
111         return IIC_IRQ_IPI0 + IIC_NUM_IPIS - 1 - ipi;
112 }
113
114 static inline int iic_irq_to_ipi(int irq)
115 {
116         return IIC_NUM_IPIS - 1 - (irq - IIC_IRQ_IPI0);
117 }
118
119 void iic_setup_cpu(void)
120 {
121         out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
122 }
123
124 void iic_cause_IPI(int cpu, int mesg)
125 {
126         out_be64(&per_cpu(iic, cpu).regs->generate, (IIC_NUM_IPIS - 1 - mesg) << 4);
127 }
128
129 u8 iic_get_target_id(int cpu)
130 {
131         return per_cpu(iic, cpu).target_id;
132 }
133 EXPORT_SYMBOL_GPL(iic_get_target_id);
134
135 struct irq_host *iic_get_irq_host(int node)
136 {
137         if (node < 0 || node >= IIC_NODE_COUNT)
138                 return NULL;
139         return iic_hosts[node];
140 }
141 EXPORT_SYMBOL_GPL(iic_get_irq_host);
142
143
144 static irqreturn_t iic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
145 {
146         int ipi = (int)(long)dev_id;
147
148         smp_message_recv(ipi, regs);
149
150         return IRQ_HANDLED;
151 }
152
153 static void iic_request_ipi(int ipi, const char *name)
154 {
155         int node, virq;
156
157         for (node = 0; node < IIC_NODE_COUNT; node++) {
158                 char *rname;
159                 if (iic_hosts[node] == NULL)
160                         continue;
161                 virq = irq_create_mapping(iic_hosts[node],
162                                           iic_ipi_to_irq(ipi), 0);
163                 if (virq == NO_IRQ) {
164                         printk(KERN_ERR
165                                "iic: failed to map IPI %s on node %d\n",
166                                name, node);
167                         continue;
168                 }
169                 rname = kzalloc(strlen(name) + 16, GFP_KERNEL);
170                 if (rname)
171                         sprintf(rname, "%s node %d", name, node);
172                 else
173                         rname = (char *)name;
174                 if (request_irq(virq, iic_ipi_action, IRQF_DISABLED,
175                                 rname, (void *)(long)ipi))
176                         printk(KERN_ERR
177                                "iic: failed to request IPI %s on node %d\n",
178                                name, node);
179         }
180 }
181
182 void iic_request_IPIs(void)
183 {
184         iic_request_ipi(PPC_MSG_CALL_FUNCTION, "IPI-call");
185         iic_request_ipi(PPC_MSG_RESCHEDULE, "IPI-resched");
186 #ifdef CONFIG_DEBUGGER
187         iic_request_ipi(PPC_MSG_DEBUGGER_BREAK, "IPI-debug");
188 #endif /* CONFIG_DEBUGGER */
189 }
190
191 #endif /* CONFIG_SMP */
192
193
194 static int iic_host_match(struct irq_host *h, struct device_node *node)
195 {
196         return h->host_data != NULL && node == h->host_data;
197 }
198
199 static int iic_host_map(struct irq_host *h, unsigned int virq,
200                         irq_hw_number_t hw, unsigned int flags)
201 {
202         if (hw < IIC_IRQ_IPI0)
203                 set_irq_chip_and_handler(virq, &iic_chip, handle_fasteoi_irq);
204         else
205                 set_irq_chip_and_handler(virq, &iic_chip, handle_percpu_irq);
206         return 0;
207 }
208
209 static int iic_host_xlate(struct irq_host *h, struct device_node *ct,
210                            u32 *intspec, unsigned int intsize,
211                            irq_hw_number_t *out_hwirq, unsigned int *out_flags)
212
213 {
214         /* Currently, we don't translate anything. That needs to be fixed as
215          * we get better defined device-trees. iic interrupts have to be
216          * explicitely mapped by whoever needs them
217          */
218         return -ENODEV;
219 }
220
221 static struct irq_host_ops iic_host_ops = {
222         .match = iic_host_match,
223         .map = iic_host_map,
224         .xlate = iic_host_xlate,
225 };
226
227 static void __init init_one_iic(unsigned int hw_cpu, unsigned long addr,
228                                 struct irq_host *host)
229 {
230         /* XXX FIXME: should locate the linux CPU number from the HW cpu
231          * number properly. We are lucky for now
232          */
233         struct iic *iic = &per_cpu(iic, hw_cpu);
234
235         iic->regs = ioremap(addr, sizeof(struct cbe_iic_thread_regs));
236         BUG_ON(iic->regs == NULL);
237
238         iic->target_id = ((hw_cpu & 2) << 3) | ((hw_cpu & 1) ? 0xf : 0xe);
239         iic->eoi_stack[0] = 0xff;
240         iic->host = host;
241         out_be64(&iic->regs->prio, 0);
242
243         printk(KERN_INFO "IIC for CPU %d at %lx mapped to %p, target id 0x%x\n",
244                hw_cpu, addr, iic->regs, iic->target_id);
245 }
246
247 static int __init setup_iic(void)
248 {
249         struct device_node *dn;
250         struct resource r0, r1;
251         struct irq_host *host;
252         int found = 0;
253         u32 *np;
254
255         for (dn = NULL;
256              (dn = of_find_node_by_name(dn,"interrupt-controller")) != NULL;) {
257                 if (!device_is_compatible(dn,
258                                      "IBM,CBEA-Internal-Interrupt-Controller"))
259                         continue;
260                 np = (u32 *)get_property(dn, "ibm,interrupt-server-ranges",
261                                          NULL);
262                 if (np == NULL) {
263                         printk(KERN_WARNING "IIC: CPU association not found\n");
264                         of_node_put(dn);
265                         return -ENODEV;
266                 }
267                 if (of_address_to_resource(dn, 0, &r0) ||
268                     of_address_to_resource(dn, 1, &r1)) {
269                         printk(KERN_WARNING "IIC: Can't resolve addresses\n");
270                         of_node_put(dn);
271                         return -ENODEV;
272                 }
273                 host = NULL;
274                 if (found < IIC_NODE_COUNT) {
275                         host = irq_alloc_host(IRQ_HOST_MAP_LINEAR,
276                                               IIC_SOURCE_COUNT,
277                                               &iic_host_ops,
278                                               IIC_IRQ_INVALID);
279                         iic_hosts[found] = host;
280                         BUG_ON(iic_hosts[found] == NULL);
281                         iic_hosts[found]->host_data = of_node_get(dn);
282                         found++;
283                 }
284                 init_one_iic(np[0], r0.start, host);
285                 init_one_iic(np[1], r1.start, host);
286         }
287
288         if (found)
289                 return 0;
290         else
291                 return -ENODEV;
292 }
293
294 void __init iic_init_IRQ(void)
295 {
296         /* Discover and initialize iics */
297         if (setup_iic() < 0)
298                 panic("IIC: Failed to initialize !\n");
299
300         /* Set master interrupt handling function */
301         ppc_md.get_irq = iic_get_irq;
302
303         /* Enable on current CPU */
304         iic_setup_cpu();
305 }