1 #include <linux/kernel.h>
2 #include <linux/stddef.h>
3 #include <linux/init.h>
4 #include <linux/sched.h>
5 #include <linux/signal.h>
6 #include <linux/irq.h>
7 #include <linux/dma-mapping.h>
8 #include <asm/prom.h>
9 #include <asm/irq.h>
10 #include <asm/io.h>
11 #include <asm/8xx_immap.h>
12 
13 #include "mpc8xx_pic.h"
14 
15 
16 #define PIC_VEC_SPURRIOUS      15
17 
18 extern int cpm_get_irq(struct pt_regs *regs);
19 
20 static struct irq_host *mpc8xx_pic_host;
21 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
22 static unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
23 static sysconf8xx_t __iomem *siu_reg;
24 
25 int cpm_get_irq(struct pt_regs *regs);
26 
mpc8xx_unmask_irq(struct irq_data * d)27 static void mpc8xx_unmask_irq(struct irq_data *d)
28 {
29 	int	bit, word;
30 	unsigned int irq_nr = (unsigned int)irqd_to_hwirq(d);
31 
32 	bit = irq_nr & 0x1f;
33 	word = irq_nr >> 5;
34 
35 	ppc_cached_irq_mask[word] |= (1 << (31-bit));
36 	out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
37 }
38 
mpc8xx_mask_irq(struct irq_data * d)39 static void mpc8xx_mask_irq(struct irq_data *d)
40 {
41 	int	bit, word;
42 	unsigned int irq_nr = (unsigned int)irqd_to_hwirq(d);
43 
44 	bit = irq_nr & 0x1f;
45 	word = irq_nr >> 5;
46 
47 	ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
48 	out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
49 }
50 
mpc8xx_ack(struct irq_data * d)51 static void mpc8xx_ack(struct irq_data *d)
52 {
53 	int	bit;
54 	unsigned int irq_nr = (unsigned int)irqd_to_hwirq(d);
55 
56 	bit = irq_nr & 0x1f;
57 	out_be32(&siu_reg->sc_sipend, 1 << (31-bit));
58 }
59 
mpc8xx_end_irq(struct irq_data * d)60 static void mpc8xx_end_irq(struct irq_data *d)
61 {
62 	int bit, word;
63 	unsigned int irq_nr = (unsigned int)irqd_to_hwirq(d);
64 
65 	bit = irq_nr & 0x1f;
66 	word = irq_nr >> 5;
67 
68 	ppc_cached_irq_mask[word] |= (1 << (31-bit));
69 	out_be32(&siu_reg->sc_simask, ppc_cached_irq_mask[word]);
70 }
71 
mpc8xx_set_irq_type(struct irq_data * d,unsigned int flow_type)72 static int mpc8xx_set_irq_type(struct irq_data *d, unsigned int flow_type)
73 {
74 	if (flow_type & IRQ_TYPE_EDGE_FALLING) {
75 		irq_hw_number_t hw = (unsigned int)irqd_to_hwirq(d);
76 		unsigned int siel = in_be32(&siu_reg->sc_siel);
77 
78 		/* only external IRQ senses are programmable */
79 		if ((hw & 1) == 0) {
80 			siel |= (0x80000000 >> hw);
81 			out_be32(&siu_reg->sc_siel, siel);
82 			__irq_set_handler_locked(d->irq, handle_edge_irq);
83 		}
84 	}
85 	return 0;
86 }
87 
88 static struct irq_chip mpc8xx_pic = {
89 	.name = "MPC8XX SIU",
90 	.irq_unmask = mpc8xx_unmask_irq,
91 	.irq_mask = mpc8xx_mask_irq,
92 	.irq_ack = mpc8xx_ack,
93 	.irq_eoi = mpc8xx_end_irq,
94 	.irq_set_type = mpc8xx_set_irq_type,
95 };
96 
mpc8xx_get_irq(void)97 unsigned int mpc8xx_get_irq(void)
98 {
99 	int irq;
100 
101 	/* For MPC8xx, read the SIVEC register and shift the bits down
102 	 * to get the irq number.
103 	 */
104 	irq = in_be32(&siu_reg->sc_sivec) >> 26;
105 
106 	if (irq == PIC_VEC_SPURRIOUS)
107 		irq = NO_IRQ;
108 
109         return irq_linear_revmap(mpc8xx_pic_host, irq);
110 
111 }
112 
mpc8xx_pic_host_map(struct irq_host * h,unsigned int virq,irq_hw_number_t hw)113 static int mpc8xx_pic_host_map(struct irq_host *h, unsigned int virq,
114 			  irq_hw_number_t hw)
115 {
116 	pr_debug("mpc8xx_pic_host_map(%d, 0x%lx)\n", virq, hw);
117 
118 	/* Set default irq handle */
119 	irq_set_chip_and_handler(virq, &mpc8xx_pic, handle_level_irq);
120 	return 0;
121 }
122 
123 
mpc8xx_pic_host_xlate(struct irq_host * h,struct device_node * ct,const u32 * intspec,unsigned int intsize,irq_hw_number_t * out_hwirq,unsigned int * out_flags)124 static int mpc8xx_pic_host_xlate(struct irq_host *h, struct device_node *ct,
125 			    const u32 *intspec, unsigned int intsize,
126 			    irq_hw_number_t *out_hwirq, unsigned int *out_flags)
127 {
128 	static unsigned char map_pic_senses[4] = {
129 		IRQ_TYPE_EDGE_RISING,
130 		IRQ_TYPE_LEVEL_LOW,
131 		IRQ_TYPE_LEVEL_HIGH,
132 		IRQ_TYPE_EDGE_FALLING,
133 	};
134 
135 	*out_hwirq = intspec[0];
136 	if (intsize > 1 && intspec[1] < 4)
137 		*out_flags = map_pic_senses[intspec[1]];
138 	else
139 		*out_flags = IRQ_TYPE_NONE;
140 
141 	return 0;
142 }
143 
144 
145 static struct irq_host_ops mpc8xx_pic_host_ops = {
146 	.map = mpc8xx_pic_host_map,
147 	.xlate = mpc8xx_pic_host_xlate,
148 };
149 
mpc8xx_pic_init(void)150 int mpc8xx_pic_init(void)
151 {
152 	struct resource res;
153 	struct device_node *np;
154 	int ret;
155 
156 	np = of_find_compatible_node(NULL, NULL, "fsl,pq1-pic");
157 	if (np == NULL)
158 		np = of_find_node_by_type(NULL, "mpc8xx-pic");
159 	if (np == NULL) {
160 		printk(KERN_ERR "Could not find fsl,pq1-pic node\n");
161 		return -ENOMEM;
162 	}
163 
164 	ret = of_address_to_resource(np, 0, &res);
165 	if (ret)
166 		goto out;
167 
168 	siu_reg = ioremap(res.start, resource_size(&res));
169 	if (siu_reg == NULL) {
170 		ret = -EINVAL;
171 		goto out;
172 	}
173 
174 	mpc8xx_pic_host = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR,
175 					 64, &mpc8xx_pic_host_ops, 64);
176 	if (mpc8xx_pic_host == NULL) {
177 		printk(KERN_ERR "MPC8xx PIC: failed to allocate irq host!\n");
178 		ret = -ENOMEM;
179 		goto out;
180 	}
181 	return 0;
182 
183 out:
184 	of_node_put(np);
185 	return ret;
186 }
187