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
34#include <asm/immap_cpm2.h>
35#include <asm/mpc8260.h>
36#include <asm/io.h>
37#include <asm/prom.h>
38#include <asm/fs_pd.h>
39
40#include "cpm2_pic.h"
41
42/* External IRQS */
43#define CPM2_IRQ_EXT1		19
44#define CPM2_IRQ_EXT7		25
45
46/* Port C IRQS */
47#define CPM2_IRQ_PORTC15	48
48#define CPM2_IRQ_PORTC0		63
49
50static intctl_cpm2_t __iomem *cpm2_intctl;
51
52static struct irq_domain *cpm2_pic_host;
53static unsigned long ppc_cached_irq_mask[2]; /* 2 32-bit registers */
54
55static const u_char irq_to_siureg[] = {
56	1, 1, 1, 1, 1, 1, 1, 1,
57	1, 1, 1, 1, 1, 1, 1, 1,
58	0, 0, 0, 0, 0, 0, 0, 0,
59	0, 0, 0, 0, 0, 0, 0, 0,
60	1, 1, 1, 1, 1, 1, 1, 1,
61	1, 1, 1, 1, 1, 1, 1, 1,
62	0, 0, 0, 0, 0, 0, 0, 0,
63	0, 0, 0, 0, 0, 0, 0, 0
64};
65
66/* bit numbers do not match the docs, these are precomputed so the bit for
67 * a given irq is (1 << irq_to_siubit[irq]) */
68static const u_char irq_to_siubit[] = {
69	 0, 15, 14, 13, 12, 11, 10,  9,
70	 8,  7,  6,  5,  4,  3,  2,  1,
71	 2,  1,  0, 14, 13, 12, 11, 10,
72	 9,  8,  7,  6,  5,  4,  3,  0,
73	31, 30, 29, 28, 27, 26, 25, 24,
74	23, 22, 21, 20, 19, 18, 17, 16,
75	16, 17, 18, 19, 20, 21, 22, 23,
76	24, 25, 26, 27, 28, 29, 30, 31,
77};
78
79static void cpm2_mask_irq(struct irq_data *d)
80{
81	int	bit, word;
82	unsigned int irq_nr = irqd_to_hwirq(d);
83
84	bit = irq_to_siubit[irq_nr];
85	word = irq_to_siureg[irq_nr];
86
87	ppc_cached_irq_mask[word] &= ~(1 << bit);
88	out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
89}
90
91static void cpm2_unmask_irq(struct irq_data *d)
92{
93	int	bit, word;
94	unsigned int irq_nr = irqd_to_hwirq(d);
95
96	bit = irq_to_siubit[irq_nr];
97	word = irq_to_siureg[irq_nr];
98
99	ppc_cached_irq_mask[word] |= 1 << bit;
100	out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
101}
102
103static void cpm2_ack(struct irq_data *d)
104{
105	int	bit, word;
106	unsigned int irq_nr = irqd_to_hwirq(d);
107
108	bit = irq_to_siubit[irq_nr];
109	word = irq_to_siureg[irq_nr];
110
111	out_be32(&cpm2_intctl->ic_sipnrh + word, 1 << bit);
112}
113
114static void cpm2_end_irq(struct irq_data *d)
115{
116	int	bit, word;
117	unsigned int irq_nr = irqd_to_hwirq(d);
118
119	bit = irq_to_siubit[irq_nr];
120	word = irq_to_siureg[irq_nr];
121
122	ppc_cached_irq_mask[word] |= 1 << bit;
123	out_be32(&cpm2_intctl->ic_simrh + word, ppc_cached_irq_mask[word]);
124
125	/*
126	 * Work around large numbers of spurious IRQs on PowerPC 82xx
127	 * systems.
128	 */
129	mb();
130}
131
132static int cpm2_set_irq_type(struct irq_data *d, unsigned int flow_type)
133{
134	unsigned int src = irqd_to_hwirq(d);
135	unsigned int vold, vnew, edibit;
136
137	/* Port C interrupts are either IRQ_TYPE_EDGE_FALLING or
138	 * IRQ_TYPE_EDGE_BOTH (default).  All others are IRQ_TYPE_EDGE_FALLING
139	 * or IRQ_TYPE_LEVEL_LOW (default)
140	 */
141	if (src >= CPM2_IRQ_PORTC15 && src <= CPM2_IRQ_PORTC0) {
142		if (flow_type == IRQ_TYPE_NONE)
143			flow_type = IRQ_TYPE_EDGE_BOTH;
144
145		if (flow_type != IRQ_TYPE_EDGE_BOTH &&
146		    flow_type != IRQ_TYPE_EDGE_FALLING)
147			goto err_sense;
148	} else {
149		if (flow_type == IRQ_TYPE_NONE)
150			flow_type = IRQ_TYPE_LEVEL_LOW;
151
152		if (flow_type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH))
153			goto err_sense;
154	}
155
156	irqd_set_trigger_type(d, flow_type);
157	if (flow_type & IRQ_TYPE_LEVEL_LOW)
158		__irq_set_handler_locked(d->irq, handle_level_irq);
159	else
160		__irq_set_handler_locked(d->irq, handle_edge_irq);
161
162	/* internal IRQ senses are LEVEL_LOW
163	 * EXT IRQ and Port C IRQ senses are programmable
164	 */
165	if (src >= CPM2_IRQ_EXT1 && src <= CPM2_IRQ_EXT7)
166			edibit = (14 - (src - CPM2_IRQ_EXT1));
167	else
168		if (src >= CPM2_IRQ_PORTC15 && src <= CPM2_IRQ_PORTC0)
169			edibit = (31 - (CPM2_IRQ_PORTC0 - src));
170		else
171			return (flow_type & IRQ_TYPE_LEVEL_LOW) ?
172				IRQ_SET_MASK_OK_NOCOPY : -EINVAL;
173
174	vold = in_be32(&cpm2_intctl->ic_siexr);
175
176	if ((flow_type & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_FALLING)
177		vnew = vold | (1 << edibit);
178	else
179		vnew = vold & ~(1 << edibit);
180
181	if (vold != vnew)
182		out_be32(&cpm2_intctl->ic_siexr, vnew);
183	return IRQ_SET_MASK_OK_NOCOPY;
184
185err_sense:
186	pr_err("CPM2 PIC: sense type 0x%x not supported\n", flow_type);
187	return -EINVAL;
188}
189
190static struct irq_chip cpm2_pic = {
191	.name = "CPM2 SIU",
192	.irq_mask = cpm2_mask_irq,
193	.irq_unmask = cpm2_unmask_irq,
194	.irq_ack = cpm2_ack,
195	.irq_eoi = cpm2_end_irq,
196	.irq_set_type = cpm2_set_irq_type,
197	.flags = IRQCHIP_EOI_IF_HANDLED,
198};
199
200unsigned int cpm2_get_irq(void)
201{
202	int irq;
203	unsigned long bits;
204
205       /* For CPM2, read the SIVEC register and shift the bits down
206         * to get the irq number.         */
207        bits = in_be32(&cpm2_intctl->ic_sivec);
208        irq = bits >> 26;
209
210	if (irq == 0)
211		return(-1);
212	return irq_linear_revmap(cpm2_pic_host, irq);
213}
214
215static int cpm2_pic_host_map(struct irq_domain *h, unsigned int virq,
216			  irq_hw_number_t hw)
217{
218	pr_debug("cpm2_pic_host_map(%d, 0x%lx)\n", virq, hw);
219
220	irq_set_status_flags(virq, IRQ_LEVEL);
221	irq_set_chip_and_handler(virq, &cpm2_pic, handle_level_irq);
222	return 0;
223}
224
225static const struct irq_domain_ops cpm2_pic_host_ops = {
226	.map = cpm2_pic_host_map,
227	.xlate = irq_domain_xlate_onetwocell,
228};
229
230void cpm2_pic_init(struct device_node *node)
231{
232	int i;
233
234	cpm2_intctl = cpm2_map(im_intctl);
235
236	/* Clear the CPM IRQ controller, in case it has any bits set
237	 * from the bootloader
238	 */
239
240	/* Mask out everything */
241
242	out_be32(&cpm2_intctl->ic_simrh, 0x00000000);
243	out_be32(&cpm2_intctl->ic_simrl, 0x00000000);
244
245	wmb();
246
247	/* Ack everything */
248	out_be32(&cpm2_intctl->ic_sipnrh, 0xffffffff);
249	out_be32(&cpm2_intctl->ic_sipnrl, 0xffffffff);
250	wmb();
251
252	/* Dummy read of the vector */
253	i = in_be32(&cpm2_intctl->ic_sivec);
254	rmb();
255
256	/* Initialize the default interrupt mapping priorities,
257	 * in case the boot rom changed something on us.
258	 */
259	out_be16(&cpm2_intctl->ic_sicr, 0);
260	out_be32(&cpm2_intctl->ic_scprrh, 0x05309770);
261	out_be32(&cpm2_intctl->ic_scprrl, 0x05309770);
262
263	/* create a legacy host */
264	cpm2_pic_host = irq_domain_add_linear(node, 64, &cpm2_pic_host_ops, NULL);
265	if (cpm2_pic_host == NULL) {
266		printk(KERN_ERR "CPM2 PIC: failed to allocate irq host!\n");
267		return;
268	}
269}
270