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authorTimothy Pearson <tpearson@raptorengineering.com>2017-08-23 14:45:25 -0500
committerTimothy Pearson <tpearson@raptorengineering.com>2017-08-23 14:45:25 -0500
commitfcbb27b0ec6dcbc5a5108cb8fb19eae64593d204 (patch)
tree22962a4387943edc841c72a4e636a068c66d58fd /arch/mips/dec/kn02-irq.c
downloadast2050-linux-kernel-fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204.zip
ast2050-linux-kernel-fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204.tar.gz
Initial import of modified Linux 2.6.28 tree
Original upstream URL: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git | branch linux-2.6.28.y
Diffstat (limited to 'arch/mips/dec/kn02-irq.c')
-rw-r--r--arch/mips/dec/kn02-irq.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/mips/dec/kn02-irq.c b/arch/mips/dec/kn02-irq.c
new file mode 100644
index 0000000..02439dc
--- /dev/null
+++ b/arch/mips/dec/kn02-irq.c
@@ -0,0 +1,84 @@
+/*
+ * linux/arch/mips/dec/kn02-irq.c
+ *
+ * DECstation 5000/200 (KN02) Control and Status Register
+ * interrupts.
+ *
+ * Copyright (c) 2002, 2003, 2005 Maciej W. Rozycki
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/types.h>
+
+#include <asm/dec/kn02.h>
+
+
+/*
+ * Bits 7:0 of the Control Register are write-only -- the
+ * corresponding bits of the Status Register have a different
+ * meaning. Hence we use a cache. It speeds up things a bit
+ * as well.
+ *
+ * There is no default value -- it has to be initialized.
+ */
+u32 cached_kn02_csr;
+
+
+static int kn02_irq_base;
+
+
+static inline void unmask_kn02_irq(unsigned int irq)
+{
+ volatile u32 *csr = (volatile u32 *)CKSEG1ADDR(KN02_SLOT_BASE +
+ KN02_CSR);
+
+ cached_kn02_csr |= (1 << (irq - kn02_irq_base + 16));
+ *csr = cached_kn02_csr;
+}
+
+static inline void mask_kn02_irq(unsigned int irq)
+{
+ volatile u32 *csr = (volatile u32 *)CKSEG1ADDR(KN02_SLOT_BASE +
+ KN02_CSR);
+
+ cached_kn02_csr &= ~(1 << (irq - kn02_irq_base + 16));
+ *csr = cached_kn02_csr;
+}
+
+static void ack_kn02_irq(unsigned int irq)
+{
+ mask_kn02_irq(irq);
+ iob();
+}
+
+static struct irq_chip kn02_irq_type = {
+ .name = "KN02-CSR",
+ .ack = ack_kn02_irq,
+ .mask = mask_kn02_irq,
+ .mask_ack = ack_kn02_irq,
+ .unmask = unmask_kn02_irq,
+};
+
+
+void __init init_kn02_irqs(int base)
+{
+ volatile u32 *csr = (volatile u32 *)CKSEG1ADDR(KN02_SLOT_BASE +
+ KN02_CSR);
+ int i;
+
+ /* Mask interrupts. */
+ cached_kn02_csr &= ~KN02_CSR_IOINTEN;
+ *csr = cached_kn02_csr;
+ iob();
+
+ for (i = base; i < base + KN02_IRQ_LINES; i++)
+ set_irq_chip_and_handler(i, &kn02_irq_type, handle_level_irq);
+
+ kn02_irq_base = base;
+}
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