| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * arch/ppc/platforms/adir_pic.c |
| 3 | * |
| 4 | * Interrupt controller support for SBS Adirondack |
| 5 | * |
| 6 | * By Michael Sokolov <msokolov@ivan.Harhan.ORG> |
| 7 | * based on the K2 and SCM versions by Matt Porter <mporter@mvista.com> |
| 8 | */ |
| 9 | |
| 10 | #include <linux/stddef.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/sched.h> |
| 13 | #include <linux/pci.h> |
| 14 | #include <linux/interrupt.h> |
| 15 | |
| 16 | #include <asm/io.h> |
| 17 | #include <asm/i8259.h> |
| 18 | #include "adir.h" |
| 19 | |
| 20 | static void adir_onboard_pic_enable(unsigned int irq); |
| 21 | static void adir_onboard_pic_disable(unsigned int irq); |
| 22 | |
| 23 | __init static void |
| 24 | adir_onboard_pic_init(void) |
| 25 | { |
| 26 | volatile u_short *maskreg = (volatile u_short *) ADIR_PROCA_INT_MASK; |
| 27 | |
| 28 | /* Disable all Adirondack onboard interrupts */ |
| 29 | out_be16(maskreg, 0xFFFF); |
| 30 | } |
| 31 | |
| 32 | static int |
| 33 | adir_onboard_pic_get_irq(void) |
| 34 | { |
| 35 | volatile u_short *statreg = (volatile u_short *) ADIR_PROCA_INT_STAT; |
| 36 | int irq; |
| 37 | u_short int_status, int_test; |
| 38 | |
| 39 | int_status = in_be16(statreg); |
| 40 | for (irq = 0, int_test = 1; irq < 16; irq++, int_test <<= 1) { |
| 41 | if (int_status & int_test) |
| 42 | break; |
| 43 | } |
| 44 | |
| 45 | if (irq == 16) |
| 46 | return -1; |
| 47 | |
| 48 | return (irq+16); |
| 49 | } |
| 50 | |
| 51 | static void |
| 52 | adir_onboard_pic_enable(unsigned int irq) |
| 53 | { |
| 54 | volatile u_short *maskreg = (volatile u_short *) ADIR_PROCA_INT_MASK; |
| 55 | |
| 56 | /* Change irq to Adirondack onboard native value */ |
| 57 | irq -= 16; |
| 58 | |
| 59 | /* Enable requested irq number */ |
| 60 | out_be16(maskreg, in_be16(maskreg) & ~(1 << irq)); |
| 61 | } |
| 62 | |
| 63 | static void |
| 64 | adir_onboard_pic_disable(unsigned int irq) |
| 65 | { |
| 66 | volatile u_short *maskreg = (volatile u_short *) ADIR_PROCA_INT_MASK; |
| 67 | |
| 68 | /* Change irq to Adirondack onboard native value */ |
| 69 | irq -= 16; |
| 70 | |
| 71 | /* Disable requested irq number */ |
| 72 | out_be16(maskreg, in_be16(maskreg) | (1 << irq)); |
| 73 | } |
| 74 | |
| 75 | static struct hw_interrupt_type adir_onboard_pic = { |
| 76 | " ADIR PIC ", |
| 77 | NULL, |
| 78 | NULL, |
| 79 | adir_onboard_pic_enable, /* unmask */ |
| 80 | adir_onboard_pic_disable, /* mask */ |
| 81 | adir_onboard_pic_disable, /* mask and ack */ |
| 82 | NULL, |
| 83 | NULL |
| 84 | }; |
| 85 | |
| 86 | static struct irqaction noop_action = { |
| 87 | .handler = no_action, |
| 88 | .flags = SA_INTERRUPT, |
| 89 | .mask = CPU_MASK_NONE, |
| 90 | .name = "82c59 primary cascade", |
| 91 | }; |
| 92 | |
| 93 | /* |
| 94 | * Linux interrupt values are assigned as follows: |
| 95 | * |
| 96 | * 0-15 VT82C686 8259 interrupts |
| 97 | * 16-31 Adirondack CPLD interrupts |
| 98 | */ |
| 99 | __init void |
| 100 | adir_init_IRQ(void) |
| 101 | { |
| 102 | int i; |
| 103 | |
| 104 | /* Initialize the cascaded 8259's on the VT82C686 */ |
| 105 | for (i=0; i<16; i++) |
| 106 | irq_desc[i].handler = &i8259_pic; |
| 107 | i8259_init(NULL); |
| 108 | |
| 109 | /* Initialize Adirondack CPLD PIC and enable 8259 interrupt cascade */ |
| 110 | for (i=16; i<32; i++) |
| 111 | irq_desc[i].handler = &adir_onboard_pic; |
| 112 | adir_onboard_pic_init(); |
| 113 | |
| 114 | /* Enable 8259 interrupt cascade */ |
| 115 | setup_irq(ADIR_IRQ_VT82C686_INTR, &noop_action); |
| 116 | } |
| 117 | |
| 118 | int |
| 119 | adir_get_irq(struct pt_regs *regs) |
| 120 | { |
| 121 | int irq; |
| 122 | |
| 123 | if ((irq = adir_onboard_pic_get_irq()) < 0) |
| 124 | return irq; |
| 125 | |
| 126 | if (irq == ADIR_IRQ_VT82C686_INTR) |
| 127 | irq = i8259_irq(regs); |
| 128 | |
| 129 | return irq; |
| 130 | } |