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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/mach-footbridge/isa-irq.c
downloadconfigs-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/mach-footbridge/isa-irq.c')
-rw-r--r--arch/arm/mach-footbridge/isa-irq.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/arch/arm/mach-footbridge/isa-irq.c b/arch/arm/mach-footbridge/isa-irq.c
new file mode 100644
index 00000000000..b21016070ea
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+++ b/arch/arm/mach-footbridge/isa-irq.c
@@ -0,0 +1,168 @@
+/*
+ * linux/arch/arm/mach-footbridge/irq.c
+ *
+ * Copyright (C) 1996-2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Changelog:
+ * 22-Aug-1998 RMK Restructured IRQ routines
+ * 03-Sep-1998 PJB Merged CATS support
+ * 20-Jan-1998 RMK Started merge of EBSA286, CATS and NetWinder
+ * 26-Jan-1999 PJB Don't use IACK on CATS
+ * 16-Mar-1999 RMK Added autodetect of ISA PICs
+ */
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/init.h>
+
+#include <asm/mach/irq.h>
+
+#include <asm/hardware.h>
+#include <asm/hardware/dec21285.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/mach-types.h>
+
+static void isa_mask_pic_lo_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << (irq & 7);
+
+ outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO);
+}
+
+static void isa_ack_pic_lo_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << (irq & 7);
+
+ outb(inb(PIC_MASK_LO) | mask, PIC_MASK_LO);
+ outb(0x20, PIC_LO);
+}
+
+static void isa_unmask_pic_lo_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << (irq & 7);
+
+ outb(inb(PIC_MASK_LO) & ~mask, PIC_MASK_LO);
+}
+
+static struct irqchip isa_lo_chip = {
+ .ack = isa_ack_pic_lo_irq,
+ .mask = isa_mask_pic_lo_irq,
+ .unmask = isa_unmask_pic_lo_irq,
+};
+
+static void isa_mask_pic_hi_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << (irq & 7);
+
+ outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI);
+}
+
+static void isa_ack_pic_hi_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << (irq & 7);
+
+ outb(inb(PIC_MASK_HI) | mask, PIC_MASK_HI);
+ outb(0x62, PIC_LO);
+ outb(0x20, PIC_HI);
+}
+
+static void isa_unmask_pic_hi_irq(unsigned int irq)
+{
+ unsigned int mask = 1 << (irq & 7);
+
+ outb(inb(PIC_MASK_HI) & ~mask, PIC_MASK_HI);
+}
+
+static struct irqchip isa_hi_chip = {
+ .ack = isa_ack_pic_hi_irq,
+ .mask = isa_mask_pic_hi_irq,
+ .unmask = isa_unmask_pic_hi_irq,
+};
+
+static void
+isa_irq_handler(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
+{
+ unsigned int isa_irq = *(unsigned char *)PCIIACK_BASE;
+
+ if (isa_irq < _ISA_IRQ(0) || isa_irq >= _ISA_IRQ(16)) {
+ do_bad_IRQ(isa_irq, desc, regs);
+ return;
+ }
+
+ desc = irq_desc + isa_irq;
+ desc->handle(isa_irq, desc, regs);
+}
+
+static struct irqaction irq_cascade = { .handler = no_action, .name = "cascade", };
+static struct resource pic1_resource = { "pic1", 0x20, 0x3f };
+static struct resource pic2_resource = { "pic2", 0xa0, 0xbf };
+
+void __init isa_init_irq(unsigned int host_irq)
+{
+ unsigned int irq;
+
+ /*
+ * Setup, and then probe for an ISA PIC
+ * If the PIC is not there, then we
+ * ignore the PIC.
+ */
+ outb(0x11, PIC_LO);
+ outb(_ISA_IRQ(0), PIC_MASK_LO); /* IRQ number */
+ outb(0x04, PIC_MASK_LO); /* Slave on Ch2 */
+ outb(0x01, PIC_MASK_LO); /* x86 */
+ outb(0xf5, PIC_MASK_LO); /* pattern: 11110101 */
+
+ outb(0x11, PIC_HI);
+ outb(_ISA_IRQ(8), PIC_MASK_HI); /* IRQ number */
+ outb(0x02, PIC_MASK_HI); /* Slave on Ch1 */
+ outb(0x01, PIC_MASK_HI); /* x86 */
+ outb(0xfa, PIC_MASK_HI); /* pattern: 11111010 */
+
+ outb(0x0b, PIC_LO);
+ outb(0x0b, PIC_HI);
+
+ if (inb(PIC_MASK_LO) == 0xf5 && inb(PIC_MASK_HI) == 0xfa) {
+ outb(0xff, PIC_MASK_LO);/* mask all IRQs */
+ outb(0xff, PIC_MASK_HI);/* mask all IRQs */
+ } else {
+ printk(KERN_INFO "IRQ: ISA PIC not found\n");
+ host_irq = (unsigned int)-1;
+ }
+
+ if (host_irq != (unsigned int)-1) {
+ for (irq = _ISA_IRQ(0); irq < _ISA_IRQ(8); irq++) {
+ set_irq_chip(irq, &isa_lo_chip);
+ set_irq_handler(irq, do_level_IRQ);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+
+ for (irq = _ISA_IRQ(8); irq < _ISA_IRQ(16); irq++) {
+ set_irq_chip(irq, &isa_hi_chip);
+ set_irq_handler(irq, do_level_IRQ);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+
+ request_resource(&ioport_resource, &pic1_resource);
+ request_resource(&ioport_resource, &pic2_resource);
+ setup_irq(IRQ_ISA_CASCADE, &irq_cascade);
+
+ set_irq_chained_handler(host_irq, isa_irq_handler);
+
+ /*
+ * On the NetWinder, don't automatically
+ * enable ISA IRQ11 when it is requested.
+ * There appears to be a missing pull-up
+ * resistor on this line.
+ */
+ if (machine_is_netwinder())
+ set_irq_flags(_ISA_IRQ(11), IRQF_VALID |
+ IRQF_PROBE | IRQF_NOAUTOEN);
+ }
+}
+
+