diff options
Diffstat (limited to 'arch/mips/powertv/asic/asic_int.c')
-rw-r--r-- | arch/mips/powertv/asic/asic_int.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/mips/powertv/asic/asic_int.c b/arch/mips/powertv/asic/asic_int.c new file mode 100644 index 000000000000..80b2eed21ac3 --- /dev/null +++ b/arch/mips/powertv/asic/asic_int.c | |||
@@ -0,0 +1,125 @@ | |||
1 | /* | ||
2 | * Carsten Langgaard, carstenl@mips.com | ||
3 | * Copyright (C) 2000, 2001, 2004 MIPS Technologies, Inc. | ||
4 | * Copyright (C) 2001 Ralf Baechle | ||
5 | * Portions copyright (C) 2009 Cisco Systems, Inc. | ||
6 | * | ||
7 | * This program is free software; you can distribute it and/or modify it | ||
8 | * under the terms of the GNU General Public License (Version 2) as | ||
9 | * published by the Free Software Foundation. | ||
10 | * | ||
11 | * This program is distributed in the hope it will be useful, but WITHOUT | ||
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | ||
14 | * for more details. | ||
15 | * | ||
16 | * You should have received a copy of the GNU General Public License along | ||
17 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
18 | * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. | ||
19 | * | ||
20 | * Routines for generic manipulation of the interrupts found on the PowerTV | ||
21 | * platform. | ||
22 | * | ||
23 | * The interrupt controller is located in the South Bridge a PIIX4 device | ||
24 | * with two internal 82C95 interrupt controllers. | ||
25 | */ | ||
26 | #include <linux/init.h> | ||
27 | #include <linux/irq.h> | ||
28 | #include <linux/sched.h> | ||
29 | #include <linux/slab.h> | ||
30 | #include <linux/interrupt.h> | ||
31 | #include <linux/kernel_stat.h> | ||
32 | #include <linux/kernel.h> | ||
33 | #include <linux/random.h> | ||
34 | |||
35 | #include <asm/irq_cpu.h> | ||
36 | #include <linux/io.h> | ||
37 | #include <asm/irq_regs.h> | ||
38 | #include <asm/mips-boards/generic.h> | ||
39 | |||
40 | #include <asm/mach-powertv/asic_regs.h> | ||
41 | |||
42 | static DEFINE_SPINLOCK(asic_irq_lock); | ||
43 | |||
44 | static inline int get_int(void) | ||
45 | { | ||
46 | unsigned long flags; | ||
47 | int irq; | ||
48 | |||
49 | spin_lock_irqsave(&asic_irq_lock, flags); | ||
50 | |||
51 | irq = (asic_read(int_int_scan) >> 4) - 1; | ||
52 | |||
53 | if (irq == 0 || irq >= NR_IRQS) | ||
54 | irq = -1; | ||
55 | |||
56 | spin_unlock_irqrestore(&asic_irq_lock, flags); | ||
57 | |||
58 | return irq; | ||
59 | } | ||
60 | |||
61 | static void asic_irqdispatch(void) | ||
62 | { | ||
63 | int irq; | ||
64 | |||
65 | irq = get_int(); | ||
66 | if (irq < 0) | ||
67 | return; /* interrupt has already been cleared */ | ||
68 | |||
69 | do_IRQ(irq); | ||
70 | } | ||
71 | |||
72 | static inline int clz(unsigned long x) | ||
73 | { | ||
74 | __asm__( | ||
75 | " .set push \n" | ||
76 | " .set mips32 \n" | ||
77 | " clz %0, %1 \n" | ||
78 | " .set pop \n" | ||
79 | : "=r" (x) | ||
80 | : "r" (x)); | ||
81 | |||
82 | return x; | ||
83 | } | ||
84 | |||
85 | /* | ||
86 | * Version of ffs that only looks at bits 12..15. | ||
87 | */ | ||
88 | static inline unsigned int irq_ffs(unsigned int pending) | ||
89 | { | ||
90 | return fls(pending) - 1 + CAUSEB_IP; | ||
91 | } | ||
92 | |||
93 | /* | ||
94 | * TODO: check how it works under EIC mode. | ||
95 | */ | ||
96 | asmlinkage void plat_irq_dispatch(void) | ||
97 | { | ||
98 | unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM; | ||
99 | int irq; | ||
100 | |||
101 | irq = irq_ffs(pending); | ||
102 | |||
103 | if (irq == CAUSEF_IP3) | ||
104 | asic_irqdispatch(); | ||
105 | else if (irq >= 0) | ||
106 | do_IRQ(irq); | ||
107 | else | ||
108 | spurious_interrupt(); | ||
109 | } | ||
110 | |||
111 | void __init arch_init_irq(void) | ||
112 | { | ||
113 | int i; | ||
114 | |||
115 | asic_irq_init(); | ||
116 | |||
117 | /* | ||
118 | * Initialize interrupt exception vectors. | ||
119 | */ | ||
120 | if (cpu_has_veic || cpu_has_vint) { | ||
121 | int nvec = cpu_has_veic ? 64 : 8; | ||
122 | for (i = 0; i < nvec; i++) | ||
123 | set_vi_handler(i, asic_irqdispatch); | ||
124 | } | ||
125 | } | ||