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-rw-r--r--arch/sh/boards/mach-cayman/irq.c157
1 files changed, 157 insertions, 0 deletions
diff --git a/arch/sh/boards/mach-cayman/irq.c b/arch/sh/boards/mach-cayman/irq.c
new file mode 100644
index 000000000..724e8b727
--- /dev/null
+++ b/arch/sh/boards/mach-cayman/irq.c
@@ -0,0 +1,157 @@
+/*
+ * arch/sh/mach-cayman/irq.c - SH-5 Cayman Interrupt Support
+ *
+ * This file handles the board specific parts of the Cayman interrupt system
+ *
+ * Copyright (C) 2002 Stuart Menefy
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/signal.h>
+#include <cpu/irq.h>
+#include <asm/page.h>
+
+/* Setup for the SMSC FDC37C935 / LAN91C100FD */
+#define SMSC_IRQ IRQ_IRL1
+
+/* Setup for PCI Bus 2, which transmits interrupts via the EPLD */
+#define PCI2_IRQ IRQ_IRL3
+
+unsigned long epld_virt;
+
+#define EPLD_BASE 0x04002000
+#define EPLD_STATUS_BASE (epld_virt + 0x10)
+#define EPLD_MASK_BASE (epld_virt + 0x20)
+
+/* Note the SMSC SuperIO chip and SMSC LAN chip interrupts are all muxed onto
+ the same SH-5 interrupt */
+
+static irqreturn_t cayman_interrupt_smsc(int irq, void *dev_id)
+{
+ printk(KERN_INFO "CAYMAN: spurious SMSC interrupt\n");
+ return IRQ_NONE;
+}
+
+static irqreturn_t cayman_interrupt_pci2(int irq, void *dev_id)
+{
+ printk(KERN_INFO "CAYMAN: spurious PCI interrupt, IRQ %d\n", irq);
+ return IRQ_NONE;
+}
+
+static struct irqaction cayman_action_smsc = {
+ .name = "Cayman SMSC Mux",
+ .handler = cayman_interrupt_smsc,
+};
+
+static struct irqaction cayman_action_pci2 = {
+ .name = "Cayman PCI2 Mux",
+ .handler = cayman_interrupt_pci2,
+};
+
+static void enable_cayman_irq(struct irq_data *data)
+{
+ unsigned int irq = data->irq;
+ unsigned long flags;
+ unsigned long mask;
+ unsigned int reg;
+ unsigned char bit;
+
+ irq -= START_EXT_IRQS;
+ reg = EPLD_MASK_BASE + ((irq / 8) << 2);
+ bit = 1<<(irq % 8);
+ local_irq_save(flags);
+ mask = __raw_readl(reg);
+ mask |= bit;
+ __raw_writel(mask, reg);
+ local_irq_restore(flags);
+}
+
+static void disable_cayman_irq(struct irq_data *data)
+{
+ unsigned int irq = data->irq;
+ unsigned long flags;
+ unsigned long mask;
+ unsigned int reg;
+ unsigned char bit;
+
+ irq -= START_EXT_IRQS;
+ reg = EPLD_MASK_BASE + ((irq / 8) << 2);
+ bit = 1<<(irq % 8);
+ local_irq_save(flags);
+ mask = __raw_readl(reg);
+ mask &= ~bit;
+ __raw_writel(mask, reg);
+ local_irq_restore(flags);
+}
+
+struct irq_chip cayman_irq_type = {
+ .name = "Cayman-IRQ",
+ .irq_unmask = enable_cayman_irq,
+ .irq_mask = disable_cayman_irq,
+};
+
+int cayman_irq_demux(int evt)
+{
+ int irq = intc_evt_to_irq[evt];
+
+ if (irq == SMSC_IRQ) {
+ unsigned long status;
+ int i;
+
+ status = __raw_readl(EPLD_STATUS_BASE) &
+ __raw_readl(EPLD_MASK_BASE) & 0xff;
+ if (status == 0) {
+ irq = -1;
+ } else {
+ for (i=0; i<8; i++) {
+ if (status & (1<<i))
+ break;
+ }
+ irq = START_EXT_IRQS + i;
+ }
+ }
+
+ if (irq == PCI2_IRQ) {
+ unsigned long status;
+ int i;
+
+ status = __raw_readl(EPLD_STATUS_BASE + 3 * sizeof(u32)) &
+ __raw_readl(EPLD_MASK_BASE + 3 * sizeof(u32)) & 0xff;
+ if (status == 0) {
+ irq = -1;
+ } else {
+ for (i=0; i<8; i++) {
+ if (status & (1<<i))
+ break;
+ }
+ irq = START_EXT_IRQS + (3 * 8) + i;
+ }
+ }
+
+ return irq;
+}
+
+void init_cayman_irq(void)
+{
+ int i;
+
+ epld_virt = (unsigned long)ioremap_nocache(EPLD_BASE, 1024);
+ if (!epld_virt) {
+ printk(KERN_ERR "Cayman IRQ: Unable to remap EPLD\n");
+ return;
+ }
+
+ for (i = 0; i < NR_EXT_IRQS; i++) {
+ irq_set_chip_and_handler(START_EXT_IRQS + i,
+ &cayman_irq_type, handle_level_irq);
+ }
+
+ /* Setup the SMSC interrupt */
+ setup_irq(SMSC_IRQ, &cayman_action_smsc);
+ setup_irq(PCI2_IRQ, &cayman_action_pci2);
+}