Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
[linux-2.6] / arch / powerpc / platforms / celleb / interrupt.c
1 /*
2  * Celleb/Beat Interrupt controller
3  *
4  * (C) Copyright 2006-2007 TOSHIBA CORPORATION
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  */
20
21 #include <linux/init.h>
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/percpu.h>
25 #include <linux/types.h>
26
27 #include <asm/machdep.h>
28
29 #include "interrupt.h"
30 #include "beat_wrapper.h"
31
32 #define MAX_IRQS        NR_IRQS
33 static DEFINE_SPINLOCK(beatic_irq_mask_lock);
34 static uint64_t beatic_irq_mask_enable[(MAX_IRQS+255)/64];
35 static uint64_t beatic_irq_mask_ack[(MAX_IRQS+255)/64];
36
37 static struct irq_host *beatic_host = NULL;
38
39 /*
40  * In this implementation, "virq" == "IRQ plug number",
41  * "(irq_hw_number_t)hwirq" == "IRQ outlet number".
42  */
43
44 /* assumption: locked */
45 static inline void beatic_update_irq_mask(unsigned int irq_plug)
46 {
47         int off;
48         unsigned long masks[4];
49
50         off = (irq_plug / 256) * 4;
51         masks[0] = beatic_irq_mask_enable[off + 0]
52                    & beatic_irq_mask_ack[off + 0];
53         masks[1] = beatic_irq_mask_enable[off + 1]
54                    & beatic_irq_mask_ack[off + 1];
55         masks[2] = beatic_irq_mask_enable[off + 2]
56                    & beatic_irq_mask_ack[off + 2];
57         masks[3] = beatic_irq_mask_enable[off + 3]
58                    & beatic_irq_mask_ack[off + 3];
59         if (beat_set_interrupt_mask(irq_plug&~255UL,
60                 masks[0], masks[1], masks[2], masks[3]) != 0)
61                 panic("Failed to set mask IRQ!");
62 }
63
64 static void beatic_mask_irq(unsigned int irq_plug)
65 {
66         unsigned long flags;
67
68         spin_lock_irqsave(&beatic_irq_mask_lock, flags);
69         beatic_irq_mask_enable[irq_plug/64] &= ~(1UL << (63 - (irq_plug%64)));
70         beatic_update_irq_mask(irq_plug);
71         spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
72 }
73
74 static void beatic_unmask_irq(unsigned int irq_plug)
75 {
76         unsigned long flags;
77
78         spin_lock_irqsave(&beatic_irq_mask_lock, flags);
79         beatic_irq_mask_enable[irq_plug/64] |= 1UL << (63 - (irq_plug%64));
80         beatic_update_irq_mask(irq_plug);
81         spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
82 }
83
84 static void beatic_ack_irq(unsigned int irq_plug)
85 {
86         unsigned long flags;
87
88         spin_lock_irqsave(&beatic_irq_mask_lock, flags);
89         beatic_irq_mask_ack[irq_plug/64] &= ~(1UL << (63 - (irq_plug%64)));
90         beatic_update_irq_mask(irq_plug);
91         spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
92 }
93
94 static void beatic_end_irq(unsigned int irq_plug)
95 {
96         s64 err;
97         unsigned long flags;
98
99         if ((err = beat_downcount_of_interrupt(irq_plug)) != 0) {
100                 if ((err & 0xFFFFFFFF) != 0xFFFFFFF5) /* -11: wrong state */
101                         panic("Failed to downcount IRQ! Error = %16lx", err);
102
103                 printk(KERN_ERR "IRQ over-downcounted, plug %d\n", irq_plug);
104         }
105         spin_lock_irqsave(&beatic_irq_mask_lock, flags);
106         beatic_irq_mask_ack[irq_plug/64] |= 1UL << (63 - (irq_plug%64));
107         beatic_update_irq_mask(irq_plug);
108         spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
109 }
110
111 static struct irq_chip beatic_pic = {
112         .typename = " CELL-BEAT ",
113         .unmask = beatic_unmask_irq,
114         .mask = beatic_mask_irq,
115         .eoi = beatic_end_irq,
116 };
117
118 /*
119  * Dispose binding hardware IRQ number (hw) and Virtuql IRQ number (virq),
120  * update flags.
121  *
122  * Note that the number (virq) is already assigned at upper layer.
123  */
124 static void beatic_pic_host_unmap(struct irq_host *h, unsigned int virq)
125 {
126         beat_destruct_irq_plug(virq);
127 }
128
129 /*
130  * Create or update binding hardware IRQ number (hw) and Virtuql
131  * IRQ number (virq). This is called only once for a given mapping.
132  *
133  * Note that the number (virq) is already assigned at upper layer.
134  */
135 static int beatic_pic_host_map(struct irq_host *h, unsigned int virq,
136                                irq_hw_number_t hw)
137 {
138         struct irq_desc *desc = get_irq_desc(virq);
139         int64_t err;
140
141         if ((err = beat_construct_and_connect_irq_plug(virq, hw)) < 0)
142                 return -EIO;
143
144         desc->status |= IRQ_LEVEL;
145         set_irq_chip_and_handler(virq, &beatic_pic, handle_fasteoi_irq);
146         return 0;
147 }
148
149 /*
150  * Update binding hardware IRQ number (hw) and Virtuql
151  * IRQ number (virq). This is called only once for a given mapping.
152  */
153 static void beatic_pic_host_remap(struct irq_host *h, unsigned int virq,
154                                irq_hw_number_t hw)
155 {
156         beat_construct_and_connect_irq_plug(virq, hw);
157 }
158
159 /*
160  * Translate device-tree interrupt spec to irq_hw_number_t style (ulong),
161  * to pass away to irq_create_mapping().
162  *
163  * Called from irq_create_of_mapping() only.
164  * Note: We have only 1 entry to translate.
165  */
166 static int beatic_pic_host_xlate(struct irq_host *h, struct device_node *ct,
167                                  u32 *intspec, unsigned int intsize,
168                                  irq_hw_number_t *out_hwirq,
169                                  unsigned int *out_flags)
170 {
171         u64 *intspec2 = (u64 *)intspec;
172
173         *out_hwirq = *intspec2;
174         *out_flags |= IRQ_TYPE_LEVEL_LOW;
175         return 0;
176 }
177
178 static struct irq_host_ops beatic_pic_host_ops = {
179         .map = beatic_pic_host_map,
180         .remap = beatic_pic_host_remap,
181         .unmap = beatic_pic_host_unmap,
182         .xlate = beatic_pic_host_xlate,
183 };
184
185 /*
186  * Get an IRQ number
187  * Note: returns VIRQ
188  */
189 static inline unsigned int beatic_get_irq_plug(void)
190 {
191         int i;
192         uint64_t        pending[4], ub;
193
194         for (i = 0; i < MAX_IRQS; i += 256) {
195                 beat_detect_pending_interrupts(i, pending);
196                 __asm__ ("cntlzd %0,%1":"=r"(ub):
197                         "r"(pending[0] & beatic_irq_mask_enable[i/64+0]
198                                        & beatic_irq_mask_ack[i/64+0]));
199                 if (ub != 64)
200                         return i + ub + 0;
201                 __asm__ ("cntlzd %0,%1":"=r"(ub):
202                         "r"(pending[1] & beatic_irq_mask_enable[i/64+1]
203                                        & beatic_irq_mask_ack[i/64+1]));
204                 if (ub != 64)
205                         return i + ub + 64;
206                 __asm__ ("cntlzd %0,%1":"=r"(ub):
207                         "r"(pending[2] & beatic_irq_mask_enable[i/64+2]
208                                        & beatic_irq_mask_ack[i/64+2]));
209                 if (ub != 64)
210                         return i + ub + 128;
211                 __asm__ ("cntlzd %0,%1":"=r"(ub):
212                         "r"(pending[3] & beatic_irq_mask_enable[i/64+3]
213                                        & beatic_irq_mask_ack[i/64+3]));
214                 if (ub != 64)
215                         return i + ub + 192;
216         }
217
218         return NO_IRQ;
219 }
220 unsigned int beatic_get_irq(void)
221 {
222         unsigned int ret;
223
224         ret = beatic_get_irq_plug();
225         if (ret != NO_IRQ)
226                 beatic_ack_irq(ret);
227         return ret;
228 }
229
230 /*
231  */
232 void __init beatic_init_IRQ(void)
233 {
234         int     i;
235
236         memset(beatic_irq_mask_enable, 0, sizeof(beatic_irq_mask_enable));
237         memset(beatic_irq_mask_ack, 255, sizeof(beatic_irq_mask_ack));
238         for (i = 0; i < MAX_IRQS; i += 256)
239                 beat_set_interrupt_mask(i, 0L, 0L, 0L, 0L);
240
241         /* Set out get_irq function */
242         ppc_md.get_irq = beatic_get_irq;
243
244         /* Allocate an irq host */
245         beatic_host = irq_alloc_host(IRQ_HOST_MAP_NOMAP, 0,
246                                          &beatic_pic_host_ops,
247                                          0);
248         BUG_ON(beatic_host == NULL);
249         irq_set_default_host(beatic_host);
250 }
251
252 #ifdef CONFIG_SMP
253
254 /* Nullified to compile with SMP mode */
255 void beatic_setup_cpu(int cpu)
256 {
257 }
258
259 void beatic_cause_IPI(int cpu, int mesg)
260 {
261 }
262
263 void beatic_request_IPIs(void)
264 {
265 }
266 #endif /* CONFIG_SMP */
267
268 void beatic_deinit_IRQ(void)
269 {
270         int     i;
271
272         for (i = 1; i < NR_IRQS; i++)
273                 beat_destruct_irq_plug(i);
274 }