summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorVineet Gupta <vgupta@synopsys.com>2013-01-18 09:42:18 (GMT)
committerVineet Gupta <vgupta@synopsys.com>2013-02-11 14:30:37 (GMT)
commitbacdf4809afade180a8f2171adb4cf7ec715d139 (patch)
treea2cdf633a0604f3b736d4686b404463243f78a12
parent9d42c84f9182da615e7ec0964ce585f23c822349 (diff)
downloadlinux-bacdf4809afade180a8f2171adb4cf7ec715d139.tar.xz
ARC: Interrupt Handling
This contains: -bootup arch IRQ init: init_IRQ(), arc_init_IRQ() -generic IRQ subsystem glue: arch_do_IRQ() -basic IRQ chip setup for in-core intc Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r--arch/arc/include/asm/arcregs.h3
-rw-r--r--arch/arc/include/asm/hw_irq.h7
-rw-r--r--arch/arc/include/asm/irq.h22
-rw-r--r--arch/arc/kernel/irq.c107
-rw-r--r--arch/arc/plat-arcfpga/irq.c15
5 files changed, 152 insertions, 2 deletions
diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h
index 8ca8faf..3fccb04 100644
--- a/arch/arc/include/asm/arcregs.h
+++ b/arch/arc/include/asm/arcregs.h
@@ -11,6 +11,9 @@
#ifdef __KERNEL__
+/* Build Configuration Registers */
+#define ARC_REG_VECBASE_BCR 0x68
+
/* status32 Bits Positions */
#define STATUS_H_BIT 0 /* CPU Halted */
#define STATUS_E1_BIT 1 /* Int 1 enable */
diff --git a/arch/arc/include/asm/hw_irq.h b/arch/arc/include/asm/hw_irq.h
new file mode 100644
index 0000000..fd565ab
--- /dev/null
+++ b/arch/arc/include/asm/hw_irq.h
@@ -0,0 +1,7 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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.
+ */
diff --git a/arch/arc/include/asm/irq.h b/arch/arc/include/asm/irq.h
new file mode 100644
index 0000000..ca4aeba
--- /dev/null
+++ b/arch/arc/include/asm/irq.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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.
+ */
+
+#ifndef __ASM_ARC_IRQ_H
+#define __ASM_ARC_IRQ_H
+
+/* Platform Independent IRQs */
+#define TIMER0_IRQ 3
+#define TIMER1_IRQ 4
+
+#include <asm-generic/irq.h>
+
+extern void __init arc_init_IRQ(void);
+extern void __init plat_init_IRQ(void);
+extern int __init get_hw_config_num_irq(void);
+
+#endif
diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c
index c4e9b25..2f399eb 100644
--- a/arch/arc/kernel/irq.c
+++ b/arch/arc/kernel/irq.c
@@ -9,8 +9,111 @@
#include <linux/interrupt.h>
#include <linux/module.h>
-#include <asm/irqflags.h>
-#include <asm/arcregs.h>
+#include <asm/sections.h>
+#include <asm/irq.h>
+
+/*
+ * Early Hardware specific Interrupt setup
+ * -Called very early (start_kernel -> setup_arch -> setup_processor)
+ * -Platform Independent (must for any ARC700)
+ * -Needed for each CPU (hence not foldable into init_IRQ)
+ *
+ * what it does ?
+ * -setup Vector Table Base Reg - in case Linux not linked at 0x8000_0000
+ * -Disable all IRQs (on CPU side)
+ */
+void __init arc_init_IRQ(void)
+{
+ int level_mask = level_mask;
+
+ write_aux_reg(AUX_INTR_VEC_BASE, _int_vec_base_lds);
+
+ /* Disable all IRQs: enable them as devices request */
+ write_aux_reg(AUX_IENABLE, 0);
+}
+
+/*
+ * ARC700 core includes a simple on-chip intc supporting
+ * -per IRQ enable/disable
+ * -2 levels of interrupts (high/low)
+ * -all interrupts being level triggered
+ *
+ * To reduce platform code, we assume all IRQs directly hooked-up into intc.
+ * Platforms with external intc, hence cascaded IRQs, are free to over-ride
+ * below, per IRQ.
+ */
+
+static void arc_mask_irq(struct irq_data *data)
+{
+ arch_mask_irq(data->irq);
+}
+
+static void arc_unmask_irq(struct irq_data *data)
+{
+ arch_unmask_irq(data->irq);
+}
+
+static struct irq_chip onchip_intc = {
+ .name = "ARC In-core Intc",
+ .irq_mask = arc_mask_irq,
+ .irq_unmask = arc_unmask_irq,
+};
+
+void __init init_onchip_IRQ(void)
+{
+ int i;
+
+ for (i = 0; i < NR_IRQS; i++)
+ irq_set_chip_and_handler(i, &onchip_intc, handle_level_irq);
+
+#ifdef CONFIG_SMP
+ irq_set_chip_and_handler(TIMER0_IRQ, &onchip_intc, handle_percpu_irq);
+#endif
+}
+
+/*
+ * Late Interrupt system init called from start_kernel for Boot CPU only
+ *
+ * Since slab must already be initialized, platforms can start doing any
+ * needed request_irq( )s
+ */
+void __init init_IRQ(void)
+{
+ init_onchip_IRQ();
+ plat_init_IRQ();
+}
+
+/*
+ * "C" Entry point for any ARC ISR, called from low level vector handler
+ * @irq is the vector number read from ICAUSE reg of on-chip intc
+ */
+void arch_do_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ irq_enter();
+ generic_handle_irq(irq);
+ irq_exit();
+ set_irq_regs(old_regs);
+}
+
+int __init get_hw_config_num_irq(void)
+{
+ uint32_t val = read_aux_reg(ARC_REG_VECBASE_BCR);
+
+ switch (val & 0x03) {
+ case 0:
+ return 16;
+ case 1:
+ return 32;
+ case 2:
+ return 8;
+ default:
+ return 0;
+ }
+
+ return 0;
+}
void arch_local_irq_enable(void)
{
diff --git a/arch/arc/plat-arcfpga/irq.c b/arch/arc/plat-arcfpga/irq.c
new file mode 100644
index 0000000..ed72636
--- /dev/null
+++ b/arch/arc/plat-arcfpga/irq.c
@@ -0,0 +1,15 @@
+/*
+ * ARC FPGA Platform IRQ hookups
+ *
+ * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * 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.
+ */
+
+#include <linux/interrupt.h>
+
+void __init plat_init_IRQ(void)
+{
+}