+static volatile char *sbc82xx_i8259_map;
+static char sbc82xx_i8259_mask = 0xff;
+static spinlock_t sbc82xx_i8259_lock = SPIN_LOCK_UNLOCKED;
+
+static void sbc82xx_i8259_mask_and_ack_irq(unsigned int irq_nr)
+{
+ unsigned long flags;
+
+ irq_nr -= NR_SIU_INTS;
+
+ spin_lock_irqsave(&sbc82xx_i8259_lock, flags);
+ sbc82xx_i8259_mask |= 1 << irq_nr;
+ (void) sbc82xx_i8259_map[1]; /* Dummy read */
+ sbc82xx_i8259_map[1] = sbc82xx_i8259_mask;
+ sbc82xx_i8259_map[0] = 0x20; /* OCW2: Non-specific EOI */
+ spin_unlock_irqrestore(&sbc82xx_i8259_lock, flags);
+}
+
+static void sbc82xx_i8259_mask_irq(unsigned int irq_nr)
+{
+ unsigned long flags;
+
+ irq_nr -= NR_SIU_INTS;
+
+ spin_lock_irqsave(&sbc82xx_i8259_lock, flags);
+ sbc82xx_i8259_mask |= 1 << irq_nr;
+ sbc82xx_i8259_map[1] = sbc82xx_i8259_mask;
+ spin_unlock_irqrestore(&sbc82xx_i8259_lock, flags);
+}
+
+static void sbc82xx_i8259_unmask_irq(unsigned int irq_nr)
+{
+ unsigned long flags;
+
+ irq_nr -= NR_SIU_INTS;
+
+ spin_lock_irqsave(&sbc82xx_i8259_lock, flags);
+ sbc82xx_i8259_mask &= ~(1 << irq_nr);
+ sbc82xx_i8259_map[1] = sbc82xx_i8259_mask;
+ spin_unlock_irqrestore(&sbc82xx_i8259_lock, flags);
+}
+
+static void sbc82xx_i8259_end_irq(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))
+ && irq_desc[irq].action)
+ sbc82xx_i8259_unmask_irq(irq);
+}
+
+
+struct hw_interrupt_type sbc82xx_i8259_ic = {
+ .typename = " i8259 ",
+ .enable = sbc82xx_i8259_unmask_irq,
+ .disable = sbc82xx_i8259_mask_irq,
+ .ack = sbc82xx_i8259_mask_and_ack_irq,
+ .end = sbc82xx_i8259_end_irq,
+};
+
+static irqreturn_t sbc82xx_i8259_demux(int irq, void *dev_id, struct pt_regs *regs)
+{
+ spin_lock(&sbc82xx_i8259_lock);
+
+ sbc82xx_i8259_map[0] = 0x0c; /* OCW3: Read IR register on RD# pulse */
+ irq = sbc82xx_i8259_map[0] & 7; /* Read IRR */
+
+ if (irq == 7) {
+ /* Possible spurious interrupt */
+ int isr;
+ sbc82xx_i8259_map[0] = 0x0b; /* OCW3: Read IS register on RD# pulse */
+ isr = sbc82xx_i8259_map[0]; /* Read ISR */
+
+ if (!(isr & 0x80)) {
+ printk(KERN_INFO "Spurious i8259 interrupt\n");
+ return IRQ_HANDLED;
+ }
+ }
+ ppc_irq_dispatch_handler(regs, NR_SIU_INTS + irq);
+ return IRQ_HANDLED;
+}
+
+void __init sbc82xx_init_IRQ(void)
+{
+ volatile memctl_cpm2_t *mc = &cpm2_immr->im_memctl;
+ volatile intctl_cpm2_t *ic = &cpm2_immr->im_intctl;
+ int i;
+
+ callback_init_IRQ();
+
+ /* u-boot doesn't always set the board up correctly */
+ mc->memc_br5 = 0;
+ mc->memc_or5 = 0xfff00856;
+ mc->memc_br5 = 0x22000801;
+
+ sbc82xx_i8259_map = ioremap(0x22008000, 2);
+ if (!sbc82xx_i8259_map) {
+ printk(KERN_CRIT "Mapping i8259 interrupt controller failed\n");
+ return;
+ }
+
+ /* Set up the interrupt handlers for the i8259 IRQs */
+ for (i = NR_SIU_INTS; i < NR_SIU_INTS + 8; i++) {
+ irq_desc[i].handler = &sbc82xx_i8259_ic;
+ irq_desc[i].status |= IRQ_LEVEL;
+ }
+
+ /* make IRQ6 level sensitive */
+ ic->ic_siexr &= ~(1 << (14 - (SIU_INT_IRQ6 - SIU_INT_IRQ1)));
+ irq_desc[SIU_INT_IRQ6].status |= IRQ_LEVEL;
+
+ /* Initialise the i8259 */
+ sbc82xx_i8259_map[0] = 0x1b; /* ICW1: Level, no cascade, ICW4 */
+ sbc82xx_i8259_map[1] = 0x00; /* ICW2: vector base */
+ /* No ICW3 (no cascade) */
+ sbc82xx_i8259_map[1] = 0x01; /* ICW4: 8086 mode, normal EOI */
+
+ sbc82xx_i8259_map[0] = 0x0b; /* OCW3: Read IS register on RD# pulse */
+
+ sbc82xx_i8259_map[1] = sbc82xx_i8259_mask; /* Set interrupt mask */
+
+ /* Request cascade IRQ */
+ if (request_irq(SIU_INT_IRQ6, sbc82xx_i8259_demux, SA_INTERRUPT,
+ "i8259 demux", 0)) {
+ printk("Installation of i8259 IRQ demultiplexer failed.\n");
+ }
+}
+
+static int sbc82xx_pci_map_irq(struct pci_dev *dev, unsigned char idsel,
+ unsigned char pin)
+{
+ static char pci_irq_table[][4] = {
+ /*
+ * PCI IDSEL/INTPIN->INTLINE
+ * A B C D
+ */
+ { SBC82xx_PIRQA, SBC82xx_PIRQB, SBC82xx_PIRQC, SBC82xx_PIRQD }, /* IDSEL 16 - PMC slot */
+ { SBC82xx_PC_IRQA, SBC82xx_PC_IRQB, -1, -1 }, /* IDSEL 17 - CardBus */
+ { SBC82xx_PIRQA, SBC82xx_PIRQB, SBC82xx_PIRQC, SBC82xx_PIRQD }, /* IDSEL 18 - PCI-X bridge */
+ };
+
+ const long min_idsel = 16, max_idsel = 18, irqs_per_slot = 4;
+
+ return PCI_IRQ_TABLE_LOOKUP;
+}
+
+
+