From: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
The common i8259_irq() will make kernel hang on booting, herein, we
write our own instead.
The IP6 is shared by the bonito interrupt and the perfcounter interrupt.
Signed-off-by: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
---
arch/mips/loongson/Makefile | 6 ++
arch/mips/loongson/lemote-2f/Makefile | 5 +
arch/mips/loongson/lemote-2f/irq.c | 130 +++++++++++++++++++++++++++++++++
3 files changed, 141 insertions(+), 0 deletions(-)
create mode 100644 arch/mips/loongson/lemote-2f/Makefile
create mode 100644 arch/mips/loongson/lemote-2f/irq.c
diff --git a/arch/mips/loongson/Makefile b/arch/mips/loongson/Makefile
index 39048c4..2b76cb0 100644
--- a/arch/mips/loongson/Makefile
+++ b/arch/mips/loongson/Makefile
@@ -9,3 +9,9 @@ obj-$(CONFIG_MACH_LOONGSON) += common/
#
obj-$(CONFIG_LEMOTE_FULOONG2E) += fuloong-2e/
+
+#
+# Lemote loongson2f family machines
+#
+
+obj-$(CONFIG_LEMOTE_MACH2F) += lemote-2f/
diff --git a/arch/mips/loongson/lemote-2f/Makefile b/arch/mips/loongson/lemote-2f/Makefile
new file mode 100644
index 0000000..2e18897
--- /dev/null
+++ b/arch/mips/loongson/lemote-2f/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for lemote loongson2f family machines
+#
+
+obj-y += irq.o
diff --git a/arch/mips/loongson/lemote-2f/irq.c b/arch/mips/loongson/lemote-2f/irq.c
new file mode 100644
index 0000000..98f6984
--- /dev/null
+++ b/arch/mips/loongson/lemote-2f/irq.c
@@ -0,0 +1,130 @@
+/*
+ * Copyright (C) 2007 Lemote Inc.
+ * Author: Fuxin Zhang, zhangfx@xxxxxxxxxx
+ *
+ * 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/interrupt.h>
+
+#include <asm/irq_cpu.h>
+#include <asm/i8259.h>
+#include <asm/mipsregs.h>
+
+#include <loongson.h>
+#include <machine.h>
+
+#define LOONGSON_TIMER_IRQ (MIPS_CPU_IRQ_BASE + 7) /* cpu timer */
+#define LOONGSON_PERFCNT_IRQ (MIPS_CPU_IRQ_BASE + 6) /* cpu perf counter */
+#define LOONGSON_NORTH_BRIDGE_IRQ (MIPS_CPU_IRQ_BASE + 6) /* bonito */
+#define LOONGSON_UART_IRQ (MIPS_CPU_IRQ_BASE + 3) /* cpu serial port */
+#define LOONGSON_SOUTH_BRIDGE_IRQ (MIPS_CPU_IRQ_BASE + 2) /* i8259 */
+
+#define LOONGSON_INT_BIT_INT0 (1 << 11)
+#define LOONGSON_INT_BIT_INT1 (1 << 12)
+
+/* The common i8259_irq() make the kernel hang on booting, Seems we can not get
+ * the irq via the IRR directly, herein, we access the ISR instead. */
+static inline int mach_i8259_irq(void)
+{
+ int irq, isr;
+
+ irq = -1;
+
+ if ((LOONGSON_INTISR & LOONGSON_INTEN) & LOONGSON_INT_BIT_INT0) {
+ spin_lock(&i8259A_lock);
+ isr = inb(PIC_MASTER_CMD) &
+ ~inb(PIC_MASTER_IMR) & ~(1 << PIC_CASCADE_IR);
+ if (!isr)
+ isr = (inb(PIC_SLAVE_CMD) & ~inb(PIC_SLAVE_IMR)) << 8;
+ irq = ffs(isr) - 1;
+ if (unlikely(irq == 7)) {
+ /*
+ * This may be a spurious interrupt.
+ *
+ * Read the interrupt status register (ISR). If the most
+ * significant bit is not set then there is no valid
+ * interrupt.
+ */
+ outb(0x0B, PIC_MASTER_ISR); /* ISR register */
+ if (~inb(PIC_MASTER_ISR) & 0x80)
+ irq = -1;
+ }
+ spin_unlock(&i8259A_lock);
+ }
+
+ return irq;
+}
+
+static void i8259_irqdispatch(void)
+{
+ int irq;
+
+ irq = mach_i8259_irq();
+ if (irq >= 0)
+ do_IRQ(irq);
+ else
+ spurious_interrupt();
+}
+
+void mach_irq_dispatch(unsigned int pending)
+{
+ if (pending & CAUSEF_IP7)
+ do_IRQ(LOONGSON_TIMER_IRQ);
+ else if (pending & CAUSEF_IP6) { /* North Bridge, Perf counter */
+#ifdef CONFIG_OPROFILE
+ do_IRQ(LOONGSON2_PERFCNT_IRQ);
+#endif
+ bonito_irqdispatch();
+ } else if (pending & CAUSEF_IP3) /* CPU UART */
+ do_IRQ(LOONGSON_UART_IRQ);
+ else if (pending & CAUSEF_IP2) /* South Bridge */
+ i8259_irqdispatch();
+ else
+ spurious_interrupt();
+}
+
+void __init set_irq_trigger_mode(void)
+{
+ /* setup cs5536 as high level trigger */
+ LOONGSON_INTPOL = LOONGSON_INT_BIT_INT0 | LOONGSON_INT_BIT_INT1;
+ LOONGSON_INTEDGE &= ~(LOONGSON_INT_BIT_INT0 | LOONGSON_INT_BIT_INT1);
+}
+
+static irqreturn_t ip6_action(int cpl, void *dev_id)
+{
+ return IRQ_HANDLED;
+}
+
+struct irqaction ip6_irqaction = {
+ .handler = ip6_action,
+ .name = "cascade",
+ .flags = IRQF_SHARED,
+};
+
+struct irqaction cascade_irqaction = {
+ .handler = no_action,
+ .name = "cascade",
+};
+
+void __init mach_init_irq(void)
+{
+ /* init all controller
+ * 0-15 ------> i8259 interrupt
+ * 16-23 ------> mips cpu interrupt
+ * 32-63 ------> bonito irq
+ */
+
+ /* Sets the first-level interrupt dispatcher. */
+ mips_cpu_irq_init();
+ init_i8259_irqs();
+ bonito_irq_init();
+
+ /* setup north bridge irq (bonito) */
+ setup_irq(LOONGSON_NORTH_BRIDGE_IRQ, &ip6_irqaction);
+ /* setup source bridge irq (i8259) */
+ setup_irq(LOONGSON_SOUTH_BRIDGE_IRQ, &cascade_irqaction);
+}
--
1.6.2.1
