1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/init.h>
3 #include <linux/list.h>
4 #include <linux/io.h>
5
6 #include <asm/mach/irq.h>
7 #include <asm/hardware/iomd.h>
8 #include <asm/irq.h>
9 #include <asm/fiq.h>
10
11 // These are offsets from the stat register for each IRQ bank
12 #define STAT 0x00
13 #define REQ 0x04
14 #define CLR 0x04
15 #define MASK 0x08
16
17 static const u8 irq_prio_h[256] = {
18 0, 8, 9, 8,10,10,10,10,11,11,11,11,10,10,10,10,
19 12, 8, 9, 8,10,10,10,10,11,11,11,11,10,10,10,10,
20 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
21 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
22 14,14,14,14,10,10,10,10,11,11,11,11,10,10,10,10,
23 14,14,14,14,10,10,10,10,11,11,11,11,10,10,10,10,
24 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
25 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
26 15,15,15,15,10,10,10,10,11,11,11,11,10,10,10,10,
27 15,15,15,15,10,10,10,10,11,11,11,11,10,10,10,10,
28 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
29 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
30 15,15,15,15,10,10,10,10,11,11,11,11,10,10,10,10,
31 15,15,15,15,10,10,10,10,11,11,11,11,10,10,10,10,
32 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
33 13,13,13,13,10,10,10,10,11,11,11,11,10,10,10,10,
34 };
35
36 static const u8 irq_prio_d[256] = {
37 0,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
38 20,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
39 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
40 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
41 22,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
42 22,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
43 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
44 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
45 23,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
46 23,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
47 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
48 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
49 22,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
50 22,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
51 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
52 21,16,17,16,18,16,17,16,19,16,17,16,18,16,17,16,
53 };
54
55 static const u8 irq_prio_l[256] = {
56 0, 0, 1, 0, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
57 4, 0, 1, 0, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
58 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
59 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
60 6, 6, 6, 6, 6, 6, 6, 6, 3, 3, 3, 3, 3, 3, 3, 3,
61 6, 6, 6, 6, 6, 6, 6, 6, 3, 3, 3, 3, 3, 3, 3, 3,
62 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
63 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
64 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
65 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
66 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
67 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
68 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
69 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
70 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
71 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
72 };
73
iomd_get_irq_nr(void)74 static int iomd_get_irq_nr(void)
75 {
76 int irq;
77 u8 reg;
78
79 /* get highest priority first */
80 reg = readb(IOC_BASE + IOMD_IRQREQB);
81 irq = irq_prio_h[reg];
82 if (irq)
83 return irq;
84
85 /* get DMA */
86 reg = readb(IOC_BASE + IOMD_DMAREQ);
87 irq = irq_prio_d[reg];
88 if (irq)
89 return irq;
90
91 /* get low priority */
92 reg = readb(IOC_BASE + IOMD_IRQREQA);
93 irq = irq_prio_l[reg];
94 if (irq)
95 return irq;
96 return 0;
97 }
98
iomd_handle_irq(struct pt_regs * regs)99 static void iomd_handle_irq(struct pt_regs *regs)
100 {
101 int irq;
102
103 do {
104 irq = iomd_get_irq_nr();
105 if (irq)
106 generic_handle_irq(irq);
107 } while (irq);
108 }
109
iomd_get_base(struct irq_data * d)110 static void __iomem *iomd_get_base(struct irq_data *d)
111 {
112 void *cd = irq_data_get_irq_chip_data(d);
113
114 return (void __iomem *)(unsigned long)cd;
115 }
116
iomd_set_base_mask(unsigned int irq,void __iomem * base,u32 mask)117 static void iomd_set_base_mask(unsigned int irq, void __iomem *base, u32 mask)
118 {
119 struct irq_data *d = irq_get_irq_data(irq);
120
121 d->mask = mask;
122 irq_set_chip_data(irq, (void *)(unsigned long)base);
123 }
124
iomd_irq_mask_ack(struct irq_data * d)125 static void iomd_irq_mask_ack(struct irq_data *d)
126 {
127 void __iomem *base = iomd_get_base(d);
128 unsigned int val, mask = d->mask;
129
130 val = readb(base + MASK);
131 writeb(val & ~mask, base + MASK);
132 writeb(mask, base + CLR);
133 }
134
iomd_irq_mask(struct irq_data * d)135 static void iomd_irq_mask(struct irq_data *d)
136 {
137 void __iomem *base = iomd_get_base(d);
138 unsigned int val, mask = d->mask;
139
140 val = readb(base + MASK);
141 writeb(val & ~mask, base + MASK);
142 }
143
iomd_irq_unmask(struct irq_data * d)144 static void iomd_irq_unmask(struct irq_data *d)
145 {
146 void __iomem *base = iomd_get_base(d);
147 unsigned int val, mask = d->mask;
148
149 val = readb(base + MASK);
150 writeb(val | mask, base + MASK);
151 }
152
153 static struct irq_chip iomd_chip_clr = {
154 .irq_mask_ack = iomd_irq_mask_ack,
155 .irq_mask = iomd_irq_mask,
156 .irq_unmask = iomd_irq_unmask,
157 };
158
159 static struct irq_chip iomd_chip_noclr = {
160 .irq_mask = iomd_irq_mask,
161 .irq_unmask = iomd_irq_unmask,
162 };
163
164 extern unsigned char rpc_default_fiq_start, rpc_default_fiq_end;
165
rpc_init_irq(void)166 void __init rpc_init_irq(void)
167 {
168 unsigned int irq, clr, set;
169
170 iomd_writeb(0, IOMD_IRQMASKA);
171 iomd_writeb(0, IOMD_IRQMASKB);
172 iomd_writeb(0, IOMD_FIQMASK);
173 iomd_writeb(0, IOMD_DMAMASK);
174
175 set_fiq_handler(&rpc_default_fiq_start,
176 &rpc_default_fiq_end - &rpc_default_fiq_start);
177
178 set_handle_irq(iomd_handle_irq);
179
180 for (irq = 0; irq < NR_IRQS; irq++) {
181 clr = IRQ_NOREQUEST;
182 set = 0;
183
184 if (irq <= 6 || (irq >= 9 && irq <= 15))
185 clr |= IRQ_NOPROBE;
186
187 if (irq == 21 || (irq >= 16 && irq <= 19) ||
188 irq == IRQ_KEYBOARDTX)
189 set |= IRQ_NOAUTOEN;
190
191 switch (irq) {
192 case 0 ... 7:
193 irq_set_chip_and_handler(irq, &iomd_chip_clr,
194 handle_level_irq);
195 irq_modify_status(irq, clr, set);
196 iomd_set_base_mask(irq, IOMD_BASE + IOMD_IRQSTATA,
197 BIT(irq));
198 break;
199
200 case 8 ... 15:
201 irq_set_chip_and_handler(irq, &iomd_chip_noclr,
202 handle_level_irq);
203 irq_modify_status(irq, clr, set);
204 iomd_set_base_mask(irq, IOMD_BASE + IOMD_IRQSTATB,
205 BIT(irq - 8));
206 break;
207
208 case 16 ... 21:
209 irq_set_chip_and_handler(irq, &iomd_chip_noclr,
210 handle_level_irq);
211 irq_modify_status(irq, clr, set);
212 iomd_set_base_mask(irq, IOMD_BASE + IOMD_DMASTAT,
213 BIT(irq - 16));
214 break;
215
216 case 64 ... 71:
217 irq_set_chip(irq, &iomd_chip_noclr);
218 irq_modify_status(irq, clr, set);
219 iomd_set_base_mask(irq, IOMD_BASE + IOMD_FIQSTAT,
220 BIT(irq - 64));
221 break;
222 }
223 }
224
225 init_FIQ(FIQ_START);
226 }
227