powerpc/spufs: set nlink count for spufs root correctly
[linux-2.6] / arch / powerpc / platforms / cell / beat_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 "beat_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;
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         err = beat_downcount_of_interrupt(irq_plug);
100         if (err != 0) {
101                 if ((err & 0xFFFFFFFF) != 0xFFFFFFF5) /* -11: wrong state */
102                         panic("Failed to downcount IRQ! Error = %16lx", err);
103
104                 printk(KERN_ERR "IRQ over-downcounted, plug %d\n", irq_plug);
105         }
106         spin_lock_irqsave(&beatic_irq_mask_lock, flags);
107         beatic_irq_mask_ack[irq_plug/64] |= 1UL << (63 - (irq_plug%64));
108         beatic_update_irq_mask(irq_plug);
109         spin_unlock_irqrestore(&beatic_irq_mask_lock, flags);
110 }
111
112 static struct irq_chip beatic_pic = {
113         .typename = " CELL-BEAT ",
114         .unmask = beatic_unmask_irq,
115         .mask = beatic_mask_irq,
116         .eoi = beatic_end_irq,
117 };
118
119 /*
120  * Dispose binding hardware IRQ number (hw) and Virtuql IRQ number (virq),
121  * update flags.
122  *
123  * Note that the number (virq) is already assigned at upper layer.
124  */
125 static void beatic_pic_host_unmap(struct irq_host *h, unsigned int virq)
126 {
127         beat_destruct_irq_plug(virq);
128 }
129
130 /*
131  * Create or update binding hardware IRQ number (hw) and Virtuql
132  * IRQ number (virq). This is called only once for a given mapping.
133  *
134  * Note that the number (virq) is already assigned at upper layer.
135  */
136 static int beatic_pic_host_map(struct irq_host *h, unsigned int virq,
137                                irq_hw_number_t hw)
138 {
139         struct irq_desc *desc = get_irq_desc(virq);
140         int64_t err;
141
142         err = beat_construct_and_connect_irq_plug(virq, hw);
143         if (err < 0)
144                 return -EIO;
145
146         desc->status |= IRQ_LEVEL;
147         set_irq_chip_and_handler(virq, &beatic_pic, handle_fasteoi_irq);
148         return 0;
149 }
150
151 /*
152  * Update binding hardware IRQ number (hw) and Virtuql
153  * IRQ number (virq). This is called only once for a given mapping.
154  */
155 static void beatic_pic_host_remap(struct irq_host *h, unsigned int virq,
156                                irq_hw_number_t hw)
157 {
158         beat_construct_and_connect_irq_plug(virq, hw);
159 }
160
161 /*
162  * Translate device-tree interrupt spec to irq_hw_number_t style (ulong),
163  * to pass away to irq_create_mapping().
164  *
165  * Called from irq_create_of_mapping() only.
166  * Note: We have only 1 entry to translate.
167  */
168 static int beatic_pic_host_xlate(struct irq_host *h, struct device_node *ct,
169                                  u32 *intspec, unsigned int intsize,
170                                  irq_hw_number_t *out_hwirq,
171                                  unsigned int *out_flags)
172 {
173         u64 *intspec2 = (u64 *)intspec;
174
175         *out_hwirq = *intspec2;
176         *out_flags |= IRQ_TYPE_LEVEL_LOW;
177         return 0;
178 }
179
180 static int beatic_pic_host_match(struct irq_host *h, struct device_node *np)
181 {
182         /* Match all */
183         return 1;
184 }
185
186 static struct irq_host_ops beatic_pic_host_ops = {
187         .map = beatic_pic_host_map,
188         .remap = beatic_pic_host_remap,
189         .unmap = beatic_pic_host_unmap,
190         .xlate = beatic_pic_host_xlate,
191         .match = beatic_pic_host_match,
192 };
193
194 /*
195  * Get an IRQ number
196  * Note: returns VIRQ
197  */
198 static inline unsigned int beatic_get_irq_plug(void)
199 {
200         int i;
201         uint64_t        pending[4], ub;
202
203         for (i = 0; i < MAX_IRQS; i += 256) {
204                 beat_detect_pending_interrupts(i, pending);
205                 __asm__ ("cntlzd %0,%1":"=r"(ub):
206                         "r"(pending[0] & beatic_irq_mask_enable[i/64+0]
207                                        & beatic_irq_mask_ack[i/64+0]));
208                 if (ub != 64)
209                         return i + ub + 0;
210                 __asm__ ("cntlzd %0,%1":"=r"(ub):
211                         "r"(pending[1] & beatic_irq_mask_enable[i/64+1]
212                                        & beatic_irq_mask_ack[i/64+1]));
213                 if (ub != 64)
214                         return i + ub + 64;
215                 __asm__ ("cntlzd %0,%1":"=r"(ub):
216                         "r"(pending[2] & beatic_irq_mask_enable[i/64+2]
217                                        & beatic_irq_mask_ack[i/64+2]));
218                 if (ub != 64)
219                         return i + ub + 128;
220                 __asm__ ("cntlzd %0,%1":"=r"(ub):
221                         "r"(pending[3] & beatic_irq_mask_enable[i/64+3]
222                                        & beatic_irq_mask_ack[i/64+3]));
223                 if (ub != 64)
224                         return i + ub + 192;
225         }
226
227         return NO_IRQ;
228 }
229 unsigned int beatic_get_irq(void)
230 {
231         unsigned int ret;
232
233         ret = beatic_get_irq_plug();
234         if (ret != NO_IRQ)
235                 beatic_ack_irq(ret);
236         return ret;
237 }
238
239 /*
240  */
241 void __init beatic_init_IRQ(void)
242 {
243         int     i;
244
245         memset(beatic_irq_mask_enable, 0, sizeof(beatic_irq_mask_enable));
246         memset(beatic_irq_mask_ack, 255, sizeof(beatic_irq_mask_ack));
247         for (i = 0; i < MAX_IRQS; i += 256)
248                 beat_set_interrupt_mask(i, 0L, 0L, 0L, 0L);
249
250         /* Set out get_irq function */
251         ppc_md.get_irq = beatic_get_irq;
252
253         /* Allocate an irq host */
254         beatic_host = irq_alloc_host(NULL, IRQ_HOST_MAP_NOMAP, 0,
255                                      &beatic_pic_host_ops,
256                                          0);
257         BUG_ON(beatic_host == NULL);
258         irq_set_default_host(beatic_host);
259 }
260
261 #ifdef CONFIG_SMP
262
263 /* Nullified to compile with SMP mode */
264 void beatic_setup_cpu(int cpu)
265 {
266 }
267
268 void beatic_cause_IPI(int cpu, int mesg)
269 {
270 }
271
272 void beatic_request_IPIs(void)
273 {
274 }
275 #endif /* CONFIG_SMP */
276
277 void beatic_deinit_IRQ(void)
278 {
279         int     i;
280
281         for (i = 1; i < NR_IRQS; i++)
282                 beat_destruct_irq_plug(i);
283 }