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 00000000000..80b2eed21ac --- /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 | } | ||
