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 <vbordug@ru.mvista.com>
8 *
9 * 1999-2001 (c) Dan Malek <dan@embeddedalley.com>
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/sched.h>
31 #include <linux/signal.h>
32 #include <linux/irq.h>
33 #include <linux/irqdomain.h>
34
35 #include <asm/immap_cpm2.h>
36 #include <asm/io.h>
37
38 #include "cpm2_pic.h"
39
40 /* External IRQS */
41 #define CPM2_IRQ_EXT1 19
42 #define CPM2_IRQ_EXT7 25
43
44 /* Port C IRQS */
45 #define CPM2_IRQ_PORTC15 48
46 #define CPM2_IRQ_PORTC0 63
47
48 static intctl_cpm2_t __iomem *cpm2_intctl;
49
50 static struct irq_domain *cpm2_pic_host;
51 static unsigned long ppc_cached_irq_mask[2]; /* 2 32-bit registers */
52
53 static const u_char irq_to_siureg[] = {
54 1, 1, 1, 1, 1, 1, 1, 1,
55 1, 1, 1, 1, 1, 1, 1, 1,
56 0, 0, 0, 0, 0, 0, 0, 0,
57 0, 0, 0, 0, 0, 0, 0, 0,
58 1, 1, 1, 1, 1, 1, 1, 1,
59 1, 1, 1, 1, 1, 1, 1, 1,
60 0, 0, 0, 0, 0, 0, 0, 0,
61 0, 0, 0, 0, 0, 0, 0, 0
62 };
63
64 /* bit numbers do not match the docs, these are precomputed so the bit for
65 * a given irq is (1 << irq_to_siubit[irq]) */
66 static const u_char irq_to_siubit[] = {
67 0, 15, 14, 13, 12, 11, 10, 9,
68 8, 7, 6, 5, 4, 3, 2, 1,
69 2, 1, 0, 14, 13, 12, 11, 10,
70 9, 8, 7, 6, 5, 4, 3, 0,
71 31, 30, 29, 28, 27, 26, 25, 24,
72 23, 22, 21, 20, 19, 18, 17, 16,
73 16, 17, 18, 19, 20, 21, 22, 23,
74 24, 25, 26, 27, 28, 29, 30, 31,
75 };
76
cpm2_mask_irq(struct irq_data * d)77 static void cpm2_mask_irq(struct irq_data *d)
78 {
79 int bit, word;
80 unsigned int irq_nr = irqd_to_hwirq(d);
81
82 bit = irq_to_siubit[irq_nr];
83 word = irq_to_siureg[irq_nr];
84
85 ppc_cached_irq_mask[word] &= ~(1 << bit);
86 out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
87 }
88
cpm2_unmask_irq(struct irq_data * d)89 static void cpm2_unmask_irq(struct irq_data *d)
90 {
91 int bit, word;
92 unsigned int irq_nr = irqd_to_hwirq(d);
93
94 bit = irq_to_siubit[irq_nr];
95 word = irq_to_siureg[irq_nr];
96
97 ppc_cached_irq_mask[word] |= 1 << bit;
98 out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
99 }
100
cpm2_ack(struct irq_data * d)101 static void cpm2_ack(struct irq_data *d)
102 {
103 int bit, word;
104 unsigned int irq_nr = irqd_to_hwirq(d);
105
106 bit = irq_to_siubit[irq_nr];
107 word = irq_to_siureg[irq_nr];
108
109 out_be32(&cpm2_intctl->ic_sipnrh + word, 1 << bit);
110 }
111
cpm2_end_irq(struct irq_data * d)112 static void cpm2_end_irq(struct irq_data *d)
113 {
114 int bit, word;
115 unsigned int irq_nr = irqd_to_hwirq(d);
116
117 bit = irq_to_siubit[irq_nr];
118 word = irq_to_siureg[irq_nr];
119
120 ppc_cached_irq_mask[word] |= 1 << bit;
121 out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
122
123 /*
124 * Work around large numbers of spurious IRQs on PowerPC 82xx
125 * systems.
126 */
127 mb();
128 }
129
cpm2_set_irq_type(struct irq_data * d,unsigned int flow_type)130 static int cpm2_set_irq_type(struct irq_data *d, unsigned int flow_type)
131 {
132 unsigned int src = irqd_to_hwirq(d);
133 unsigned int vold, vnew, edibit;
134
135 /* Port C interrupts are either IRQ_TYPE_EDGE_FALLING or
136 * IRQ_TYPE_EDGE_BOTH (default). All others are IRQ_TYPE_EDGE_FALLING
137 * or IRQ_TYPE_LEVEL_LOW (default)
138 */
139 if (src >= CPM2_IRQ_PORTC15 && src <= CPM2_IRQ_PORTC0) {
140 if (flow_type == IRQ_TYPE_NONE)
141 flow_type = IRQ_TYPE_EDGE_BOTH;
142
143 if (flow_type != IRQ_TYPE_EDGE_BOTH &&
144 flow_type != IRQ_TYPE_EDGE_FALLING)
145 goto err_sense;
146 } else {
147 if (flow_type == IRQ_TYPE_NONE)
148 flow_type = IRQ_TYPE_LEVEL_LOW;
149
150 if (flow_type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH))
151 goto err_sense;
152 }
153
154 irqd_set_trigger_type(d, flow_type);
155 if (flow_type & IRQ_TYPE_LEVEL_LOW)
156 irq_set_handler_locked(d, handle_level_irq);
157 else
158 irq_set_handler_locked(d, handle_edge_irq);
159
160 /* internal IRQ senses are LEVEL_LOW
161 * EXT IRQ and Port C IRQ senses are programmable
162 */
163 if (src >= CPM2_IRQ_EXT1 && src <= CPM2_IRQ_EXT7)
164 edibit = (14 - (src - CPM2_IRQ_EXT1));
165 else
166 if (src >= CPM2_IRQ_PORTC15 && src <= CPM2_IRQ_PORTC0)
167 edibit = (31 - (CPM2_IRQ_PORTC0 - src));
168 else
169 return (flow_type & IRQ_TYPE_LEVEL_LOW) ?
170 IRQ_SET_MASK_OK_NOCOPY : -EINVAL;
171
172 vold = in_be32(&cpm2_intctl->ic_siexr);
173
174 if ((flow_type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_FALLING)
175 vnew = vold | (1 << edibit);
176 else
177 vnew = vold & ~(1 << edibit);
178
179 if (vold != vnew)
180 out_be32(&cpm2_intctl->ic_siexr, vnew);
181 return IRQ_SET_MASK_OK_NOCOPY;
182
183 err_sense:
184 pr_err("CPM2 PIC: sense type 0x%x not supported\n", flow_type);
185 return -EINVAL;
186 }
187
188 static struct irq_chip cpm2_pic = {
189 .name = "CPM2 SIU",
190 .irq_mask = cpm2_mask_irq,
191 .irq_unmask = cpm2_unmask_irq,
192 .irq_ack = cpm2_ack,
193 .irq_eoi = cpm2_end_irq,
194 .irq_set_type = cpm2_set_irq_type,
195 .flags = IRQCHIP_EOI_IF_HANDLED,
196 };
197
cpm2_get_irq(void)198 unsigned int cpm2_get_irq(void)
199 {
200 int irq;
201 unsigned long bits;
202
203 /* For CPM2, read the SIVEC register and shift the bits down
204 * to get the irq number. */
205 bits = in_be32(&cpm2_intctl->ic_sivec);
206 irq = bits >> 26;
207
208 if (irq == 0)
209 return(-1);
210 return irq_linear_revmap(cpm2_pic_host, irq);
211 }
212
cpm2_pic_host_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw)213 static int cpm2_pic_host_map(struct irq_domain *h, unsigned int virq,
214 irq_hw_number_t hw)
215 {
216 pr_debug("cpm2_pic_host_map(%d, 0x%lx)\n", virq, hw);
217
218 irq_set_status_flags(virq, IRQ_LEVEL);
219 irq_set_chip_and_handler(virq, &cpm2_pic, handle_level_irq);
220 return 0;
221 }
222
223 static const struct irq_domain_ops cpm2_pic_host_ops = {
224 .map = cpm2_pic_host_map,
225 .xlate = irq_domain_xlate_onetwocell,
226 };
227
cpm2_pic_init(struct device_node * node)228 void cpm2_pic_init(struct device_node *node)
229 {
230 int i;
231
232 cpm2_intctl = &cpm2_immr->im_intctl;
233
234 /* Clear the CPM IRQ controller, in case it has any bits set
235 * from the bootloader
236 */
237
238 /* Mask out everything */
239
240 out_be32(&cpm2_intctl->ic_simrh, 0x00000000);
241 out_be32(&cpm2_intctl->ic_simrl, 0x00000000);
242
243 wmb();
244
245 /* Ack everything */
246 out_be32(&cpm2_intctl->ic_sipnrh, 0xffffffff);
247 out_be32(&cpm2_intctl->ic_sipnrl, 0xffffffff);
248 wmb();
249
250 /* Dummy read of the vector */
251 i = in_be32(&cpm2_intctl->ic_sivec);
252 rmb();
253
254 /* Initialize the default interrupt mapping priorities,
255 * in case the boot rom changed something on us.
256 */
257 out_be16(&cpm2_intctl->ic_sicr, 0);
258 out_be32(&cpm2_intctl->ic_scprrh, 0x05309770);
259 out_be32(&cpm2_intctl->ic_scprrl, 0x05309770);
260
261 /* create a legacy host */
262 cpm2_pic_host = irq_domain_add_linear(node, 64, &cpm2_pic_host_ops, NULL);
263 if (cpm2_pic_host == NULL) {
264 printk(KERN_ERR "CPM2 PIC: failed to allocate irq host!\n");
265 return;
266 }
267 }
268