diff options
Diffstat (limited to 'arch/powerpc/sysdev/xilinx_intc.c')
-rw-r--r-- | arch/powerpc/sysdev/xilinx_intc.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/xilinx_intc.c b/arch/powerpc/sysdev/xilinx_intc.c new file mode 100644 index 000000000000..c2f17cc43dfa --- /dev/null +++ b/arch/powerpc/sysdev/xilinx_intc.c | |||
@@ -0,0 +1,151 @@ | |||
1 | /* | ||
2 | * Interrupt controller driver for Xilinx Virtex FPGAs | ||
3 | * | ||
4 | * Copyright (C) 2007 Secret Lab Technologies Ltd. | ||
5 | * | ||
6 | * This file is licensed under the terms of the GNU General Public License | ||
7 | * version 2. This program is licensed "as is" without any warranty of any | ||
8 | * kind, whether express or implied. | ||
9 | * | ||
10 | */ | ||
11 | |||
12 | /* | ||
13 | * This is a driver for the interrupt controller typically found in | ||
14 | * Xilinx Virtex FPGA designs. | ||
15 | * | ||
16 | * The interrupt sense levels are hard coded into the FPGA design with | ||
17 | * typically a 1:1 relationship between irq lines and devices (no shared | ||
18 | * irq lines). Therefore, this driver does not attempt to handle edge | ||
19 | * and level interrupts differently. | ||
20 | */ | ||
21 | #undef DEBUG | ||
22 | |||
23 | #include <linux/kernel.h> | ||
24 | #include <linux/irq.h> | ||
25 | #include <linux/of.h> | ||
26 | #include <asm/io.h> | ||
27 | #include <asm/processor.h> | ||
28 | #include <asm/irq.h> | ||
29 | |||
30 | /* | ||
31 | * INTC Registers | ||
32 | */ | ||
33 | #define XINTC_ISR 0 /* Interrupt Status */ | ||
34 | #define XINTC_IPR 4 /* Interrupt Pending */ | ||
35 | #define XINTC_IER 8 /* Interrupt Enable */ | ||
36 | #define XINTC_IAR 12 /* Interrupt Acknowledge */ | ||
37 | #define XINTC_SIE 16 /* Set Interrupt Enable bits */ | ||
38 | #define XINTC_CIE 20 /* Clear Interrupt Enable bits */ | ||
39 | #define XINTC_IVR 24 /* Interrupt Vector */ | ||
40 | #define XINTC_MER 28 /* Master Enable */ | ||
41 | |||
42 | static struct irq_host *master_irqhost; | ||
43 | |||
44 | /* | ||
45 | * IRQ Chip operations | ||
46 | */ | ||
47 | static void xilinx_intc_mask(unsigned int virq) | ||
48 | { | ||
49 | int irq = virq_to_hw(virq); | ||
50 | void * regs = get_irq_chip_data(virq); | ||
51 | pr_debug("mask: %d\n", irq); | ||
52 | out_be32(regs + XINTC_CIE, 1 << irq); | ||
53 | } | ||
54 | |||
55 | static void xilinx_intc_unmask(unsigned int virq) | ||
56 | { | ||
57 | int irq = virq_to_hw(virq); | ||
58 | void * regs = get_irq_chip_data(virq); | ||
59 | pr_debug("unmask: %d\n", irq); | ||
60 | out_be32(regs + XINTC_SIE, 1 << irq); | ||
61 | } | ||
62 | |||
63 | static void xilinx_intc_ack(unsigned int virq) | ||
64 | { | ||
65 | int irq = virq_to_hw(virq); | ||
66 | void * regs = get_irq_chip_data(virq); | ||
67 | pr_debug("ack: %d\n", irq); | ||
68 | out_be32(regs + XINTC_IAR, 1 << irq); | ||
69 | } | ||
70 | |||
71 | static struct irq_chip xilinx_intc_irqchip = { | ||
72 | .typename = "Xilinx INTC", | ||
73 | .mask = xilinx_intc_mask, | ||
74 | .unmask = xilinx_intc_unmask, | ||
75 | .ack = xilinx_intc_ack, | ||
76 | }; | ||
77 | |||
78 | /* | ||
79 | * IRQ Host operations | ||
80 | */ | ||
81 | static int xilinx_intc_map(struct irq_host *h, unsigned int virq, | ||
82 | irq_hw_number_t irq) | ||
83 | { | ||
84 | set_irq_chip_data(virq, h->host_data); | ||
85 | set_irq_chip_and_handler(virq, &xilinx_intc_irqchip, handle_level_irq); | ||
86 | set_irq_type(virq, IRQ_TYPE_NONE); | ||
87 | return 0; | ||
88 | } | ||
89 | |||
90 | static struct irq_host_ops xilinx_intc_ops = { | ||
91 | .map = xilinx_intc_map, | ||
92 | }; | ||
93 | |||
94 | struct irq_host * __init | ||
95 | xilinx_intc_init(struct device_node *np) | ||
96 | { | ||
97 | struct irq_host * irq; | ||
98 | struct resource res; | ||
99 | void * regs; | ||
100 | int rc; | ||
101 | |||
102 | /* Find and map the intc registers */ | ||
103 | rc = of_address_to_resource(np, 0, &res); | ||
104 | if (rc) { | ||
105 | printk(KERN_ERR __FILE__ ": of_address_to_resource() failed\n"); | ||
106 | return NULL; | ||
107 | } | ||
108 | regs = ioremap(res.start, 32); | ||
109 | |||
110 | printk(KERN_INFO "Xilinx intc at 0x%08X mapped to 0x%p\n", | ||
111 | res.start, regs); | ||
112 | |||
113 | /* Setup interrupt controller */ | ||
114 | out_be32(regs + XINTC_IER, 0); /* disable all irqs */ | ||
115 | out_be32(regs + XINTC_IAR, ~(u32) 0); /* Acknowledge pending irqs */ | ||
116 | out_be32(regs + XINTC_MER, 0x3UL); /* Turn on the Master Enable. */ | ||
117 | |||
118 | /* Allocate and initialize an irq_host structure. */ | ||
119 | irq = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, 32, &xilinx_intc_ops, -1); | ||
120 | if (!irq) | ||
121 | panic(__FILE__ ": Cannot allocate IRQ host\n"); | ||
122 | irq->host_data = regs; | ||
123 | return irq; | ||
124 | } | ||
125 | |||
126 | int xilinx_intc_get_irq(void) | ||
127 | { | ||
128 | void * regs = master_irqhost->host_data; | ||
129 | pr_debug("get_irq:\n"); | ||
130 | return irq_linear_revmap(master_irqhost, in_be32(regs + XINTC_IVR)); | ||
131 | } | ||
132 | |||
133 | void __init xilinx_intc_init_tree(void) | ||
134 | { | ||
135 | struct device_node *np; | ||
136 | |||
137 | /* find top level interrupt controller */ | ||
138 | for_each_compatible_node(np, NULL, "xilinx,intc") { | ||
139 | if (!of_get_property(np, "interrupts", NULL)) | ||
140 | break; | ||
141 | } | ||
142 | |||
143 | /* xilinx interrupt controller needs to be top level */ | ||
144 | BUG_ON(!np); | ||
145 | |||
146 | master_irqhost = xilinx_intc_init(np); | ||
147 | BUG_ON(!master_irqhost); | ||
148 | |||
149 | irq_set_default_host(master_irqhost); | ||
150 | of_node_put(np); | ||
151 | } | ||