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cpm2_pic.c
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1 /*
2  * Platform information definitions.
3  *
4  * Copied from arch/ppc/syslib/cpm2_pic.c with minor subsequent updates
5  * to make in work in arch/powerpc/. Original (c) belongs to Dan Malek.
6  *
7  * Author: Vitaly Bordug <[email protected]>
8  *
9  * 1999-2001 (c) Dan Malek <[email protected]>
10  * 2006 (c) MontaVista Software, Inc.
11  *
12  * This file is licensed under the terms of the GNU General Public License
13  * version 2. This program is licensed "as is" without any warranty of any
14  * kind, whether express or implied.
15  */
16 
17 /* The CPM2 internal interrupt controller. It is usually
18  * the only interrupt controller.
19  * There are two 32-bit registers (high/low) for up to 64
20  * possible interrupts.
21  *
22  * Now, the fun starts.....Interrupt Numbers DO NOT MAP
23  * in a simple arithmetic fashion to mask or pending registers.
24  * That is, interrupt 4 does not map to bit position 4.
25  * We create two tables, indexed by vector number, to indicate
26  * which register to use and which bit in the register to use.
27  */
28 
29 #include <linux/stddef.h>
30 #include <linux/init.h>
31 #include <linux/sched.h>
32 #include <linux/signal.h>
33 #include <linux/irq.h>
34 
35 #include <asm/immap_cpm2.h>
36 #include <asm/mpc8260.h>
37 #include <asm/io.h>
38 #include <asm/prom.h>
39 #include <asm/fs_pd.h>
40 
41 #include "cpm2_pic.h"
42 
43 /* External IRQS */
44 #define CPM2_IRQ_EXT1 19
45 #define CPM2_IRQ_EXT7 25
46 
47 /* Port C IRQS */
48 #define CPM2_IRQ_PORTC15 48
49 #define CPM2_IRQ_PORTC0 63
50 
51 static intctl_cpm2_t __iomem *cpm2_intctl;
52 
53 static struct irq_domain *cpm2_pic_host;
54 static unsigned long ppc_cached_irq_mask[2]; /* 2 32-bit registers */
55 
56 static const u_char irq_to_siureg[] = {
57  1, 1, 1, 1, 1, 1, 1, 1,
58  1, 1, 1, 1, 1, 1, 1, 1,
59  0, 0, 0, 0, 0, 0, 0, 0,
60  0, 0, 0, 0, 0, 0, 0, 0,
61  1, 1, 1, 1, 1, 1, 1, 1,
62  1, 1, 1, 1, 1, 1, 1, 1,
63  0, 0, 0, 0, 0, 0, 0, 0,
64  0, 0, 0, 0, 0, 0, 0, 0
65 };
66 
67 /* bit numbers do not match the docs, these are precomputed so the bit for
68  * a given irq is (1 << irq_to_siubit[irq]) */
69 static const u_char irq_to_siubit[] = {
70  0, 15, 14, 13, 12, 11, 10, 9,
71  8, 7, 6, 5, 4, 3, 2, 1,
72  2, 1, 0, 14, 13, 12, 11, 10,
73  9, 8, 7, 6, 5, 4, 3, 0,
74  31, 30, 29, 28, 27, 26, 25, 24,
75  23, 22, 21, 20, 19, 18, 17, 16,
76  16, 17, 18, 19, 20, 21, 22, 23,
77  24, 25, 26, 27, 28, 29, 30, 31,
78 };
79 
80 static void cpm2_mask_irq(struct irq_data *d)
81 {
82  int bit, word;
83  unsigned int irq_nr = irqd_to_hwirq(d);
84 
85  bit = irq_to_siubit[irq_nr];
86  word = irq_to_siureg[irq_nr];
87 
88  ppc_cached_irq_mask[word] &= ~(1 << bit);
89  out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
90 }
91 
92 static void cpm2_unmask_irq(struct irq_data *d)
93 {
94  int bit, word;
95  unsigned int irq_nr = irqd_to_hwirq(d);
96 
97  bit = irq_to_siubit[irq_nr];
98  word = irq_to_siureg[irq_nr];
99 
100  ppc_cached_irq_mask[word] |= 1 << bit;
101  out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
102 }
103 
104 static void cpm2_ack(struct irq_data *d)
105 {
106  int bit, word;
107  unsigned int irq_nr = irqd_to_hwirq(d);
108 
109  bit = irq_to_siubit[irq_nr];
110  word = irq_to_siureg[irq_nr];
111 
112  out_be32(&cpm2_intctl->ic_sipnrh + word, 1 << bit);
113 }
114 
115 static void cpm2_end_irq(struct irq_data *d)
116 {
117  int bit, word;
118  unsigned int irq_nr = irqd_to_hwirq(d);
119 
120  bit = irq_to_siubit[irq_nr];
121  word = irq_to_siureg[irq_nr];
122 
123  ppc_cached_irq_mask[word] |= 1 << bit;
124  out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
125 
126  /*
127  * Work around large numbers of spurious IRQs on PowerPC 82xx
128  * systems.
129  */
130  mb();
131 }
132 
133 static int cpm2_set_irq_type(struct irq_data *d, unsigned int flow_type)
134 {
135  unsigned int src = irqd_to_hwirq(d);
136  unsigned int vold, vnew, edibit;
137 
138  /* Port C interrupts are either IRQ_TYPE_EDGE_FALLING or
139  * IRQ_TYPE_EDGE_BOTH (default). All others are IRQ_TYPE_EDGE_FALLING
140  * or IRQ_TYPE_LEVEL_LOW (default)
141  */
142  if (src >= CPM2_IRQ_PORTC15 && src <= CPM2_IRQ_PORTC0) {
143  if (flow_type == IRQ_TYPE_NONE)
144  flow_type = IRQ_TYPE_EDGE_BOTH;
145 
146  if (flow_type != IRQ_TYPE_EDGE_BOTH &&
147  flow_type != IRQ_TYPE_EDGE_FALLING)
148  goto err_sense;
149  } else {
150  if (flow_type == IRQ_TYPE_NONE)
151  flow_type = IRQ_TYPE_LEVEL_LOW;
152 
153  if (flow_type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH))
154  goto err_sense;
155  }
156 
157  irqd_set_trigger_type(d, flow_type);
158  if (flow_type & IRQ_TYPE_LEVEL_LOW)
159  __irq_set_handler_locked(d->irq, handle_level_irq);
160  else
161  __irq_set_handler_locked(d->irq, handle_edge_irq);
162 
163  /* internal IRQ senses are LEVEL_LOW
164  * EXT IRQ and Port C IRQ senses are programmable
165  */
166  if (src >= CPM2_IRQ_EXT1 && src <= CPM2_IRQ_EXT7)
167  edibit = (14 - (src - CPM2_IRQ_EXT1));
168  else
169  if (src >= CPM2_IRQ_PORTC15 && src <= CPM2_IRQ_PORTC0)
170  edibit = (31 - (CPM2_IRQ_PORTC0 - src));
171  else
172  return (flow_type & IRQ_TYPE_LEVEL_LOW) ?
174 
175  vold = in_be32(&cpm2_intctl->ic_siexr);
176 
177  if ((flow_type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_FALLING)
178  vnew = vold | (1 << edibit);
179  else
180  vnew = vold & ~(1 << edibit);
181 
182  if (vold != vnew)
183  out_be32(&cpm2_intctl->ic_siexr, vnew);
184  return IRQ_SET_MASK_OK_NOCOPY;
185 
186 err_sense:
187  pr_err("CPM2 PIC: sense type 0x%x not supported\n", flow_type);
188  return -EINVAL;
189 }
190 
191 static struct irq_chip cpm2_pic = {
192  .name = "CPM2 SIU",
193  .irq_mask = cpm2_mask_irq,
194  .irq_unmask = cpm2_unmask_irq,
195  .irq_ack = cpm2_ack,
196  .irq_eoi = cpm2_end_irq,
197  .irq_set_type = cpm2_set_irq_type,
198  .flags = IRQCHIP_EOI_IF_HANDLED,
199 };
200 
201 unsigned int cpm2_get_irq(void)
202 {
203  int irq;
204  unsigned long bits;
205 
206  /* For CPM2, read the SIVEC register and shift the bits down
207  * to get the irq number. */
208  bits = in_be32(&cpm2_intctl->ic_sivec);
209  irq = bits >> 26;
210 
211  if (irq == 0)
212  return(-1);
213  return irq_linear_revmap(cpm2_pic_host, irq);
214 }
215 
216 static int cpm2_pic_host_map(struct irq_domain *h, unsigned int virq,
218 {
219  pr_debug("cpm2_pic_host_map(%d, 0x%lx)\n", virq, hw);
220 
221  irq_set_status_flags(virq, IRQ_LEVEL);
222  irq_set_chip_and_handler(virq, &cpm2_pic, handle_level_irq);
223  return 0;
224 }
225 
226 static const struct irq_domain_ops cpm2_pic_host_ops = {
227  .map = cpm2_pic_host_map,
229 };
230 
232 {
233  int i;
234 
235  cpm2_intctl = cpm2_map(im_intctl);
236 
237  /* Clear the CPM IRQ controller, in case it has any bits set
238  * from the bootloader
239  */
240 
241  /* Mask out everything */
242 
243  out_be32(&cpm2_intctl->ic_simrh, 0x00000000);
244  out_be32(&cpm2_intctl->ic_simrl, 0x00000000);
245 
246  wmb();
247 
248  /* Ack everything */
249  out_be32(&cpm2_intctl->ic_sipnrh, 0xffffffff);
250  out_be32(&cpm2_intctl->ic_sipnrl, 0xffffffff);
251  wmb();
252 
253  /* Dummy read of the vector */
254  i = in_be32(&cpm2_intctl->ic_sivec);
255  rmb();
256 
257  /* Initialize the default interrupt mapping priorities,
258  * in case the boot rom changed something on us.
259  */
260  out_be16(&cpm2_intctl->ic_sicr, 0);
261  out_be32(&cpm2_intctl->ic_scprrh, 0x05309770);
262  out_be32(&cpm2_intctl->ic_scprrl, 0x05309770);
263 
264  /* create a legacy host */
265  cpm2_pic_host = irq_domain_add_linear(node, 64, &cpm2_pic_host_ops, NULL);
266  if (cpm2_pic_host == NULL) {
267  printk(KERN_ERR "CPM2 PIC: failed to allocate irq host!\n");
268  return;
269  }
270 }