1/* 2 * arch/sh/mach-cayman/irq.c - SH-5 Cayman Interrupt Support 3 * 4 * This file handles the board specific parts of the Cayman interrupt system 5 * 6 * Copyright (C) 2002 Stuart Menefy 7 * 8 * This file is subject to the terms and conditions of the GNU General Public 9 * License. See the file "COPYING" in the main directory of this archive 10 * for more details. 11 */ 12#include <linux/io.h> 13#include <linux/irq.h> 14#include <linux/interrupt.h> 15#include <linux/signal.h> 16#include <cpu/irq.h> 17#include <asm/page.h> 18 19/* Setup for the SMSC FDC37C935 / LAN91C100FD */ 20#define SMSC_IRQ IRQ_IRL1 21 22/* Setup for PCI Bus 2, which transmits interrupts via the EPLD */ 23#define PCI2_IRQ IRQ_IRL3 24 25unsigned long epld_virt; 26 27#define EPLD_BASE 0x04002000 28#define EPLD_STATUS_BASE (epld_virt + 0x10) 29#define EPLD_MASK_BASE (epld_virt + 0x20) 30 31/* Note the SMSC SuperIO chip and SMSC LAN chip interrupts are all muxed onto 32 the same SH-5 interrupt */ 33 34static irqreturn_t cayman_interrupt_smsc(int irq, void *dev_id) 35{ 36 printk(KERN_INFO "CAYMAN: spurious SMSC interrupt\n"); 37 return IRQ_NONE; 38} 39 40static irqreturn_t cayman_interrupt_pci2(int irq, void *dev_id) 41{ 42 printk(KERN_INFO "CAYMAN: spurious PCI interrupt, IRQ %d\n", irq); 43 return IRQ_NONE; 44} 45 46static struct irqaction cayman_action_smsc = { 47 .name = "Cayman SMSC Mux", 48 .handler = cayman_interrupt_smsc, 49 .flags = IRQF_DISABLED, 50}; 51 52static struct irqaction cayman_action_pci2 = { 53 .name = "Cayman PCI2 Mux", 54 .handler = cayman_interrupt_pci2, 55 .flags = IRQF_DISABLED, 56}; 57 58static void enable_cayman_irq(unsigned int irq) 59{ 60 unsigned long flags; 61 unsigned long mask; 62 unsigned int reg; 63 unsigned char bit; 64 65 irq -= START_EXT_IRQS; 66 reg = EPLD_MASK_BASE + ((irq / 8) << 2); 67 bit = 1<<(irq % 8); 68 local_irq_save(flags); 69 mask = __raw_readl(reg); 70 mask |= bit; 71 __raw_writel(mask, reg); 72 local_irq_restore(flags); 73} 74 75void disable_cayman_irq(unsigned int irq) 76{ 77 unsigned long flags; 78 unsigned long mask; 79 unsigned int reg; 80 unsigned char bit; 81 82 irq -= START_EXT_IRQS; 83 reg = EPLD_MASK_BASE + ((irq / 8) << 2); 84 bit = 1<<(irq % 8); 85 local_irq_save(flags); 86 mask = __raw_readl(reg); 87 mask &= ~bit; 88 __raw_writel(mask, reg); 89 local_irq_restore(flags); 90} 91 92static void ack_cayman_irq(unsigned int irq) 93{ 94 disable_cayman_irq(irq); 95} 96 97struct irq_chip cayman_irq_type = { 98 .name = "Cayman-IRQ", 99 .unmask = enable_cayman_irq, 100 .mask = disable_cayman_irq, 101 .mask_ack = ack_cayman_irq, 102}; 103 104int cayman_irq_demux(int evt) 105{ 106 int irq = intc_evt_to_irq[evt]; 107 108 if (irq == SMSC_IRQ) { 109 unsigned long status; 110 int i; 111 112 status = __raw_readl(EPLD_STATUS_BASE) & 113 __raw_readl(EPLD_MASK_BASE) & 0xff; 114 if (status == 0) { 115 irq = -1; 116 } else { 117 for (i=0; i<8; i++) { 118 if (status & (1<<i)) 119 break; 120 } 121 irq = START_EXT_IRQS + i; 122 } 123 } 124 125 if (irq == PCI2_IRQ) { 126 unsigned long status; 127 int i; 128 129 status = __raw_readl(EPLD_STATUS_BASE + 3 * sizeof(u32)) & 130 __raw_readl(EPLD_MASK_BASE + 3 * sizeof(u32)) & 0xff; 131 if (status == 0) { 132 irq = -1; 133 } else { 134 for (i=0; i<8; i++) { 135 if (status & (1<<i)) 136 break; 137 } 138 irq = START_EXT_IRQS + (3 * 8) + i; 139 } 140 } 141 142 return irq; 143} 144 145void init_cayman_irq(void) 146{ 147 int i; 148 149 epld_virt = (unsigned long)ioremap_nocache(EPLD_BASE, 1024); 150 if (!epld_virt) { 151 printk(KERN_ERR "Cayman IRQ: Unable to remap EPLD\n"); 152 return; 153 } 154 155 for (i = 0; i < NR_EXT_IRQS; i++) { 156 set_irq_chip_and_handler(START_EXT_IRQS + i, &cayman_irq_type, 157 handle_level_irq); 158 } 159 160 /* Setup the SMSC interrupt */ 161 setup_irq(SMSC_IRQ, &cayman_action_smsc); 162 setup_irq(PCI2_IRQ, &cayman_action_pci2); 163} 164