1 /*
2 * Support for Versatile FPGA-based IRQ controllers
3 */
4 #include <linux/irq.h>
5 #include <linux/io.h>
6
7 #include <asm/mach/irq.h>
8 #include <plat/fpga-irq.h>
9
10 #define IRQ_STATUS 0x00
11 #define IRQ_RAW_STATUS 0x04
12 #define IRQ_ENABLE_SET 0x08
13 #define IRQ_ENABLE_CLEAR 0x0c
14
fpga_irq_mask(struct irq_data * d)15 static void fpga_irq_mask(struct irq_data *d)
16 {
17 struct fpga_irq_data *f = irq_data_get_irq_chip_data(d);
18 u32 mask = 1 << (d->irq - f->irq_start);
19
20 writel(mask, f->base + IRQ_ENABLE_CLEAR);
21 }
22
fpga_irq_unmask(struct irq_data * d)23 static void fpga_irq_unmask(struct irq_data *d)
24 {
25 struct fpga_irq_data *f = irq_data_get_irq_chip_data(d);
26 u32 mask = 1 << (d->irq - f->irq_start);
27
28 writel(mask, f->base + IRQ_ENABLE_SET);
29 }
30
fpga_irq_handle(unsigned int irq,struct irq_desc * desc)31 static void fpga_irq_handle(unsigned int irq, struct irq_desc *desc)
32 {
33 struct fpga_irq_data *f = irq_desc_get_handler_data(desc);
34 u32 status = readl(f->base + IRQ_STATUS);
35
36 if (status == 0) {
37 do_bad_IRQ(irq, desc);
38 return;
39 }
40
41 do {
42 irq = ffs(status) - 1;
43 status &= ~(1 << irq);
44
45 generic_handle_irq(irq + f->irq_start);
46 } while (status);
47 }
48
fpga_irq_init(int parent_irq,u32 valid,struct fpga_irq_data * f)49 void __init fpga_irq_init(int parent_irq, u32 valid, struct fpga_irq_data *f)
50 {
51 unsigned int i;
52
53 f->chip.irq_ack = fpga_irq_mask;
54 f->chip.irq_mask = fpga_irq_mask;
55 f->chip.irq_unmask = fpga_irq_unmask;
56
57 if (parent_irq != -1) {
58 irq_set_handler_data(parent_irq, f);
59 irq_set_chained_handler(parent_irq, fpga_irq_handle);
60 }
61
62 for (i = 0; i < 32; i++) {
63 if (valid & (1 << i)) {
64 unsigned int irq = f->irq_start + i;
65
66 irq_set_chip_data(irq, f);
67 irq_set_chip_and_handler(irq, &f->chip,
68 handle_level_irq);
69 set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
70 }
71 }
72 }
73