diff options
Diffstat (limited to 'arch/arm/plat-versatile/fpga-irq.c')
-rw-r--r-- | arch/arm/plat-versatile/fpga-irq.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/arm/plat-versatile/fpga-irq.c b/arch/arm/plat-versatile/fpga-irq.c new file mode 100644 index 000000000000..31d945d37e4f --- /dev/null +++ b/arch/arm/plat-versatile/fpga-irq.c | |||
@@ -0,0 +1,72 @@ | |||
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 | |||
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 | |||
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 | |||
31 | static void fpga_irq_handle(unsigned int irq, struct irq_desc *desc) | ||
32 | { | ||
33 | struct fpga_irq_data *f = get_irq_desc_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 | |||
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 | set_irq_data(parent_irq, f); | ||
59 | set_irq_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 | set_irq_chip_data(irq, f); | ||
67 | set_irq_chip(irq, &f->chip); | ||
68 | set_irq_handler(irq, handle_level_irq); | ||
69 | set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); | ||
70 | } | ||
71 | } | ||
72 | } | ||