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-rw-r--r--arch/sh/boards/cayman/irq.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/arch/sh/boards/cayman/irq.c b/arch/sh/boards/cayman/irq.c
new file mode 100644
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--- /dev/null
+++ b/arch/sh/boards/cayman/irq.c
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+/*
+ * 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 <asm/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,
+ .flags = IRQF_DISABLED,
+};
+
+static struct irqaction cayman_action_pci2 = {
+ .name = "Cayman PCI2 Mux",
+ .handler = cayman_interrupt_pci2,
+ .flags = IRQF_DISABLED,
+};
+
+static void enable_cayman_irq(unsigned int 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 = ctrl_inl(reg);
+ mask |= bit;
+ ctrl_outl(mask, reg);
+ local_irq_restore(flags);
+}
+
+void disable_cayman_irq(unsigned int 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 = ctrl_inl(reg);
+ mask &= ~bit;
+ ctrl_outl(mask, reg);
+ local_irq_restore(flags);
+}
+
+static void ack_cayman_irq(unsigned int irq)
+{
+ disable_cayman_irq(irq);
+}
+
+static void end_cayman_irq(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+ enable_cayman_irq(irq);
+}
+
+static unsigned int startup_cayman_irq(unsigned int irq)
+{
+ enable_cayman_irq(irq);
+ return 0; /* never anything pending */
+}
+
+static void shutdown_cayman_irq(unsigned int irq)
+{
+ disable_cayman_irq(irq);
+}
+
+struct hw_interrupt_type cayman_irq_type = {
+ .typename = "Cayman-IRQ",
+ .startup = startup_cayman_irq,
+ .shutdown = shutdown_cayman_irq,
+ .enable = enable_cayman_irq,
+ .disable = disable_cayman_irq,
+ .ack = ack_cayman_irq,
+ .end = end_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 = ctrl_inl(EPLD_STATUS_BASE) &
+ ctrl_inl(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 = ctrl_inl(EPLD_STATUS_BASE + 3 * sizeof(u32)) &
+ ctrl_inl(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;
+}
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_SYSCTL)
+int cayman_irq_describe(char* p, int irq)
+{
+ if (irq < NR_INTC_IRQS) {
+ return intc_irq_describe(p, irq);
+ } else if (irq < NR_INTC_IRQS + 8) {
+ return sprintf(p, "(SMSC %d)", irq - NR_INTC_IRQS);
+ } else if ((irq >= NR_INTC_IRQS + 24) && (irq < NR_INTC_IRQS + 32)) {
+ return sprintf(p, "(PCI2 %d)", irq - (NR_INTC_IRQS + 24));
+ }
+
+ return 0;
+}
+#endif
+
+void init_cayman_irq(void)
+{
+ int i;
+
+ epld_virt = onchip_remap(EPLD_BASE, 1024, "EPLD");
+ if (!epld_virt) {
+ printk(KERN_ERR "Cayman IRQ: Unable to remap EPLD\n");
+ return;
+ }
+
+ for (i=0; i<NR_EXT_IRQS; i++) {
+ irq_desc[START_EXT_IRQS + i].chip = &cayman_irq_type;
+ }
+
+ /* Setup the SMSC interrupt */
+ setup_irq(SMSC_IRQ, &cayman_action_smsc);
+ setup_irq(PCI2_IRQ, &cayman_action_pci2);
+}