[PATCH 19/19] ARC: intc: split into ARCompact ISA specific, common bits

From: Vineet Gupta
Date: Sun Jun 07 2015 - 04:41:15 EST


Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx>
---
arch/arc/include/asm/entry-compact.h | 1 +
arch/arc/include/asm/irqflags-compact.h | 181 +++++++++++++++++++++++++
arch/arc/include/asm/irqflags.h | 168 +----------------------
arch/arc/kernel/Makefile | 2 +-
arch/arc/kernel/intc-compact.c | 230 ++++++++++++++++++++++++++++++++
arch/arc/kernel/irq.c | 210 -----------------------------
arch/arc/kernel/process.c | 3 +-
7 files changed, 416 insertions(+), 379 deletions(-)
create mode 100644 arch/arc/include/asm/irqflags-compact.h
create mode 100644 arch/arc/kernel/intc-compact.c

diff --git a/arch/arc/include/asm/entry-compact.h b/arch/arc/include/asm/entry-compact.h
index 8d0dd4d1001c..a54081cf0c86 100644
--- a/arch/arc/include/asm/entry-compact.h
+++ b/arch/arc/include/asm/entry-compact.h
@@ -33,6 +33,7 @@
#define __ASM_ARC_ENTRY_COMPACT_H

#include <asm/asm-offsets.h>
+#include <asm/irqflags-compact.h>
#include <asm/thread_info.h> /* For THREAD_SIZE */

/*--------------------------------------------------------------
diff --git a/arch/arc/include/asm/irqflags-compact.h b/arch/arc/include/asm/irqflags-compact.h
new file mode 100644
index 000000000000..bdb854840f10
--- /dev/null
+++ b/arch/arc/include/asm/irqflags-compact.h
@@ -0,0 +1,181 @@
+/*
+ * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
+ * 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_IRQFLAGS_ARCOMPACT_H
+#define __ASM_IRQFLAGS_ARCOMPACT_H
+
+/* vineetg: March 2010 : local_irq_save( ) optimisation
+ * -Remove explicit mov of current status32 into reg, that is not needed
+ * -Use BIC insn instead of INVERTED + AND
+ * -Conditionally disable interrupts (if they are not enabled, don't disable)
+*/
+
+#include <asm/arcregs.h>
+
+/* status32 Reg bits related to Interrupt Handling */
+#define STATUS_E1_BIT 1 /* Int 1 enable */
+#define STATUS_E2_BIT 2 /* Int 2 enable */
+#define STATUS_A1_BIT 3 /* Int 1 active */
+#define STATUS_A2_BIT 4 /* Int 2 active */
+
+#define STATUS_E1_MASK (1<<STATUS_E1_BIT)
+#define STATUS_E2_MASK (1<<STATUS_E2_BIT)
+#define STATUS_A1_MASK (1<<STATUS_A1_BIT)
+#define STATUS_A2_MASK (1<<STATUS_A2_BIT)
+#define STATUS_IE_MASK (STATUS_E1_MASK | STATUS_E2_MASK)
+
+/* Other Interrupt Handling related Aux regs */
+#define AUX_IRQ_LEV 0x200 /* IRQ Priority: L1 or L2 */
+#define AUX_IRQ_HINT 0x201 /* For generating Soft Interrupts */
+#define AUX_IRQ_LV12 0x43 /* interrupt level register */
+
+#define AUX_IENABLE 0x40c
+#define AUX_ITRIGGER 0x40d
+#define AUX_IPULSE 0x415
+
+#ifndef __ASSEMBLY__
+
+/******************************************************************
+ * IRQ Control Macros
+ *
+ * All of them have "memory" clobber (compiler barrier) which is needed to
+ * ensure that LD/ST requiring irq safetly (R-M-W when LLSC is not available)
+ * are redone after IRQs are re-enabled (and gcc doesn't reuse stale register)
+ *
+ * Noted at the time of Abilis Timer List corruption
+ * Orig Bug + Rejected solution : https://lkml.org/lkml/2013/3/29/67
+ * Reasoning : https://lkml.org/lkml/2013/4/8/15
+ *
+ ******************************************************************/
+
+/*
+ * Save IRQ state and disable IRQs
+ */
+static inline long arch_local_irq_save(void)
+{
+ unsigned long temp, flags;
+
+ __asm__ __volatile__(
+ " lr %1, [status32] \n"
+ " bic %0, %1, %2 \n"
+ " and.f 0, %1, %2 \n"
+ " flag.nz %0 \n"
+ : "=r"(temp), "=r"(flags)
+ : "n"((STATUS_E1_MASK | STATUS_E2_MASK))
+ : "memory", "cc");
+
+ return flags;
+}
+
+/*
+ * restore saved IRQ state
+ */
+static inline void arch_local_irq_restore(unsigned long flags)
+{
+
+ __asm__ __volatile__(
+ " flag %0 \n"
+ :
+ : "r"(flags)
+ : "memory");
+}
+
+/*
+ * Unconditionally Enable IRQs
+ */
+extern void arch_local_irq_enable(void);
+
+/*
+ * Unconditionally Disable IRQs
+ */
+static inline void arch_local_irq_disable(void)
+{
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ " lr %0, [status32] \n"
+ " and %0, %0, %1 \n"
+ " flag %0 \n"
+ : "=&r"(temp)
+ : "n"(~(STATUS_E1_MASK | STATUS_E2_MASK))
+ : "memory");
+}
+
+/*
+ * save IRQ state
+ */
+static inline long arch_local_save_flags(void)
+{
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ " lr %0, [status32] \n"
+ : "=&r"(temp)
+ :
+ : "memory");
+
+ return temp;
+}
+
+/*
+ * Query IRQ state
+ */
+static inline int arch_irqs_disabled_flags(unsigned long flags)
+{
+ return !(flags & (STATUS_E1_MASK
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
+ | STATUS_E2_MASK
+#endif
+ ));
+}
+
+static inline int arch_irqs_disabled(void)
+{
+ return arch_irqs_disabled_flags(arch_local_save_flags());
+}
+
+#else
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+
+.macro TRACE_ASM_IRQ_DISABLE
+ bl trace_hardirqs_off
+.endm
+
+.macro TRACE_ASM_IRQ_ENABLE
+ bl trace_hardirqs_on
+.endm
+
+#else
+
+.macro TRACE_ASM_IRQ_DISABLE
+.endm
+
+.macro TRACE_ASM_IRQ_ENABLE
+.endm
+
+#endif
+
+.macro IRQ_DISABLE scratch
+ lr \scratch, [status32]
+ bic \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
+ flag \scratch
+ TRACE_ASM_IRQ_DISABLE
+.endm
+
+.macro IRQ_ENABLE scratch
+ lr \scratch, [status32]
+ or \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
+ flag \scratch
+ TRACE_ASM_IRQ_ENABLE
+.endm
+
+#endif /* __ASSEMBLY__ */
+
+#endif
diff --git a/arch/arc/include/asm/irqflags.h b/arch/arc/include/asm/irqflags.h
index 27ecc6975a58..333972600680 100644
--- a/arch/arc/include/asm/irqflags.h
+++ b/arch/arc/include/asm/irqflags.h
@@ -1,4 +1,5 @@
/*
+ * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
@@ -9,171 +10,6 @@
#ifndef __ASM_ARC_IRQFLAGS_H
#define __ASM_ARC_IRQFLAGS_H

-/* vineetg: March 2010 : local_irq_save( ) optimisation
- * -Remove explicit mov of current status32 into reg, that is not needed
- * -Use BIC insn instead of INVERTED + AND
- * -Conditionally disable interrupts (if they are not enabled, don't disable)
-*/
-
-#include <asm/arcregs.h>
-
-/* status32 Reg bits related to Interrupt Handling */
-#define STATUS_E1_BIT 1 /* Int 1 enable */
-#define STATUS_E2_BIT 2 /* Int 2 enable */
-#define STATUS_A1_BIT 3 /* Int 1 active */
-#define STATUS_A2_BIT 4 /* Int 2 active */
-
-#define STATUS_E1_MASK (1<<STATUS_E1_BIT)
-#define STATUS_E2_MASK (1<<STATUS_E2_BIT)
-#define STATUS_A1_MASK (1<<STATUS_A1_BIT)
-#define STATUS_A2_MASK (1<<STATUS_A2_BIT)
-
-/* Other Interrupt Handling related Aux regs */
-#define AUX_IRQ_LEV 0x200 /* IRQ Priority: L1 or L2 */
-#define AUX_IRQ_HINT 0x201 /* For generating Soft Interrupts */
-#define AUX_IRQ_LV12 0x43 /* interrupt level register */
-
-#define AUX_IENABLE 0x40c
-#define AUX_ITRIGGER 0x40d
-#define AUX_IPULSE 0x415
-
-#ifndef __ASSEMBLY__
-
-/******************************************************************
- * IRQ Control Macros
- *
- * All of them have "memory" clobber (compiler barrier) which is needed to
- * ensure that LD/ST requiring irq safetly (R-M-W when LLSC is not available)
- * are redone after IRQs are re-enabled (and gcc doesn't reuse stale register)
- *
- * Noted at the time of Abilis Timer List corruption
- * Orig Bug + Rejected solution : https://lkml.org/lkml/2013/3/29/67
- * Reasoning : https://lkml.org/lkml/2013/4/8/15
- *
- ******************************************************************/
-
-/*
- * Save IRQ state and disable IRQs
- */
-static inline long arch_local_irq_save(void)
-{
- unsigned long temp, flags;
-
- __asm__ __volatile__(
- " lr %1, [status32] \n"
- " bic %0, %1, %2 \n"
- " and.f 0, %1, %2 \n"
- " flag.nz %0 \n"
- : "=r"(temp), "=r"(flags)
- : "n"((STATUS_E1_MASK | STATUS_E2_MASK))
- : "memory", "cc");
-
- return flags;
-}
-
-/*
- * restore saved IRQ state
- */
-static inline void arch_local_irq_restore(unsigned long flags)
-{
-
- __asm__ __volatile__(
- " flag %0 \n"
- :
- : "r"(flags)
- : "memory");
-}
-
-/*
- * Unconditionally Enable IRQs
- */
-extern void arch_local_irq_enable(void);
-
-/*
- * Unconditionally Disable IRQs
- */
-static inline void arch_local_irq_disable(void)
-{
- unsigned long temp;
-
- __asm__ __volatile__(
- " lr %0, [status32] \n"
- " and %0, %0, %1 \n"
- " flag %0 \n"
- : "=&r"(temp)
- : "n"(~(STATUS_E1_MASK | STATUS_E2_MASK))
- : "memory");
-}
-
-/*
- * save IRQ state
- */
-static inline long arch_local_save_flags(void)
-{
- unsigned long temp;
-
- __asm__ __volatile__(
- " lr %0, [status32] \n"
- : "=&r"(temp)
- :
- : "memory");
-
- return temp;
-}
-
-/*
- * Query IRQ state
- */
-static inline int arch_irqs_disabled_flags(unsigned long flags)
-{
- return !(flags & (STATUS_E1_MASK
-#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
- | STATUS_E2_MASK
-#endif
- ));
-}
-
-static inline int arch_irqs_disabled(void)
-{
- return arch_irqs_disabled_flags(arch_local_save_flags());
-}
-
-#else
-
-#ifdef CONFIG_TRACE_IRQFLAGS
-
-.macro TRACE_ASM_IRQ_DISABLE
- bl trace_hardirqs_off
-.endm
-
-.macro TRACE_ASM_IRQ_ENABLE
- bl trace_hardirqs_on
-.endm
-
-#else
-
-.macro TRACE_ASM_IRQ_DISABLE
-.endm
-
-.macro TRACE_ASM_IRQ_ENABLE
-.endm
-
-#endif
-
-.macro IRQ_DISABLE scratch
- lr \scratch, [status32]
- bic \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
- flag \scratch
- TRACE_ASM_IRQ_DISABLE
-.endm
-
-.macro IRQ_ENABLE scratch
- lr \scratch, [status32]
- or \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK)
- flag \scratch
- TRACE_ASM_IRQ_ENABLE
-.endm
-
-#endif /* __ASSEMBLY__ */
+#include <asm/irqflags-compact.h>

#endif
diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile
index 024a63e90b72..cc929c0e2133 100644
--- a/arch/arc/kernel/Makefile
+++ b/arch/arc/kernel/Makefile
@@ -10,7 +10,7 @@ CFLAGS_ptrace.o += -DUTS_MACHINE='"$(UTS_MACHINE)"'

obj-y := arcksyms.o setup.o irq.o time.o reset.o ptrace.o process.o devtree.o
obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o clk.o
-obj-y += entry-compact.o
+obj-y += entry-compact.o intc-compact.o

obj-$(CONFIG_MODULES) += arcksyms.o module.o
obj-$(CONFIG_SMP) += smp.o
diff --git a/arch/arc/kernel/intc-compact.c b/arch/arc/kernel/intc-compact.c
new file mode 100644
index 000000000000..0ab1734d3b88
--- /dev/null
+++ b/arch/arc/kernel/intc-compact.c
@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) 2011-12 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>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip.h>
+#include "../../drivers/irqchip/irqchip.h"
+#include <asm/irq.h>
+
+/*
+ * Early Hardware specific Interrupt setup
+ * -Platform independent, needed for each CPU (not foldable into init_IRQ)
+ * -Called very early (start_kernel -> setup_arch -> setup_processor)
+ *
+ * what it does ?
+ * -Optionally, setup the High priority Interrupts as Level 2 IRQs
+ */
+void arc_init_IRQ(void)
+{
+ int level_mask = 0;
+
+ /* setup any high priority Interrupts (Level2 in ARCompact jargon) */
+ level_mask |= IS_ENABLED(CONFIG_ARC_IRQ3_LV2) << 3;
+ level_mask |= IS_ENABLED(CONFIG_ARC_IRQ5_LV2) << 5;
+ level_mask |= IS_ENABLED(CONFIG_ARC_IRQ6_LV2) << 6;
+
+ /*
+ * Write to register, even if no LV2 IRQs configured to reset it
+ * in case bootloader had mucked with it
+ */
+ write_aux_reg(AUX_IRQ_LEV, level_mask);
+
+ if (level_mask)
+ pr_info("Level-2 interrupts bitset %x\n", level_mask);
+}
+
+/*
+ * 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_irq_mask(struct irq_data *data)
+{
+ unsigned int ienb;
+
+ ienb = read_aux_reg(AUX_IENABLE);
+ ienb &= ~(1 << data->irq);
+ write_aux_reg(AUX_IENABLE, ienb);
+}
+
+static void arc_irq_unmask(struct irq_data *data)
+{
+ unsigned int ienb;
+
+ ienb = read_aux_reg(AUX_IENABLE);
+ ienb |= (1 << data->irq);
+ write_aux_reg(AUX_IENABLE, ienb);
+}
+
+static struct irq_chip onchip_intc = {
+ .name = "ARC In-core Intc",
+ .irq_mask = arc_irq_mask,
+ .irq_unmask = arc_irq_unmask,
+};
+
+static int arc_intc_domain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ /* For percpu devices, more efficient handler can be used */
+ //desc = irq_to_desc(irq);
+ //if (irqd_is_per_cpu(&desc->irq_data) &&
+
+ /*
+ * XXX: the IPI IRQ needs to be handled like TIMER too. However ARC core
+ * code doesn't own it (like TIMER0). ISS IDU / ezchip define it
+ * in platform header which can't be included here as it goes
+ * against multi-platform image philisophy
+ */
+ if (irq == TIMER0_IRQ)
+ irq_set_chip_and_handler(irq, &onchip_intc, handle_percpu_irq);
+ else
+ irq_set_chip_and_handler(irq, &onchip_intc, handle_level_irq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops arc_intc_domain_ops = {
+ .xlate = irq_domain_xlate_onecell,
+ .map = arc_intc_domain_map,
+};
+
+static struct irq_domain *root_domain;
+
+static int __init
+init_onchip_IRQ(struct device_node *intc, struct device_node *parent)
+{
+ if (parent)
+ panic("DeviceTree incore intc not a root irq controller\n");
+
+ root_domain = irq_domain_add_legacy(intc, NR_CPU_IRQS, 0, 0,
+ &arc_intc_domain_ops, NULL);
+
+ if (!root_domain)
+ panic("root irq domain not avail\n");
+
+ /* with this we don't need to export root_domain */
+ irq_set_default_host(root_domain);
+
+ return 0;
+}
+
+IRQCHIP_DECLARE(arc_intc, "snps,arc700-intc", init_onchip_IRQ);
+
+/*
+ * arch_local_irq_enable - Enable interrupts.
+ *
+ * 1. Explicitly called to re-enable interrupts
+ * 2. Implicitly called from spin_unlock_irq, write_unlock_irq etc
+ * which maybe in hard ISR itself
+ *
+ * Semantics of this function change depending on where it is called from:
+ *
+ * -If called from hard-ISR, it must not invert interrupt priorities
+ * e.g. suppose TIMER is high priority (Level 2) IRQ
+ * Time hard-ISR, timer_interrupt( ) calls spin_unlock_irq several times.
+ * Here local_irq_enable( ) shd not re-enable lower priority interrupts
+ * -If called from soft-ISR, it must re-enable all interrupts
+ * soft ISR are low prioity jobs which can be very slow, thus all IRQs
+ * must be enabled while they run.
+ * Now hardware context wise we may still be in L2 ISR (not done rtie)
+ * still we must re-enable both L1 and L2 IRQs
+ * Another twist is prev scenario with flow being
+ * L1 ISR ==> interrupted by L2 ISR ==> L2 soft ISR
+ * here we must not re-enable Ll as prev Ll Interrupt's h/w context will get
+ * over-written (this is deficiency in ARC700 Interrupt mechanism)
+ */
+
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS /* Complex version for 2 IRQ levels */
+
+void arch_local_irq_enable(void)
+{
+
+ unsigned long flags;
+ flags = arch_local_save_flags();
+
+ /* Allow both L1 and L2 at the onset */
+ flags |= (STATUS_E1_MASK | STATUS_E2_MASK);
+
+ /* Called from hard ISR (between irq_enter and irq_exit) */
+ if (in_irq()) {
+
+ /* If in L2 ISR, don't re-enable any further IRQs as this can
+ * cause IRQ priorities to get upside down. e.g. it could allow
+ * L1 be taken while in L2 hard ISR which is wrong not only in
+ * theory, it can also cause the dreaded L1-L2-L1 scenario
+ */
+ if (flags & STATUS_A2_MASK)
+ flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK);
+
+ /* Even if in L1 ISR, allowe Higher prio L2 IRQs */
+ else if (flags & STATUS_A1_MASK)
+ flags &= ~(STATUS_E1_MASK);
+ }
+
+ /* called from soft IRQ, ideally we want to re-enable all levels */
+
+ else if (in_softirq()) {
+
+ /* However if this is case of L1 interrupted by L2,
+ * re-enabling both may cause whaco L1-L2-L1 scenario
+ * because ARC700 allows level 1 to interrupt an active L2 ISR
+ * Thus we disable both
+ * However some code, executing in soft ISR wants some IRQs
+ * to be enabled so we re-enable L2 only
+ *
+ * How do we determine L1 intr by L2
+ * -A2 is set (means in L2 ISR)
+ * -E1 is set in this ISR's pt_regs->status32 which is
+ * saved copy of status32_l2 when l2 ISR happened
+ */
+ struct pt_regs *pt = get_irq_regs();
+ if ((flags & STATUS_A2_MASK) && pt &&
+ (pt->status32 & STATUS_A1_MASK)) {
+ /*flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK); */
+ flags &= ~(STATUS_E1_MASK);
+ }
+ }
+
+ arch_local_irq_restore(flags);
+}
+
+#else /* ! CONFIG_ARC_COMPACT_IRQ_LEVELS */
+
+/*
+ * Simpler version for only 1 level of interrupt
+ * Here we only Worry about Level 1 Bits
+ */
+void arch_local_irq_enable(void)
+{
+ unsigned long flags;
+
+ /*
+ * ARC IDE Drivers tries to re-enable interrupts from hard-isr
+ * context which is simply wrong
+ */
+ if (in_irq()) {
+ WARN_ONCE(1, "IRQ enabled from hard-isr");
+ return;
+ }
+
+ flags = arch_local_save_flags();
+ flags |= (STATUS_E1_MASK | STATUS_E2_MASK);
+ arch_local_irq_restore(flags);
+}
+#endif
+EXPORT_SYMBOL(arch_local_irq_enable);
diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c
index 620ec2fe32a9..2989a7bcf8a8 100644
--- a/arch/arc/kernel/irq.c
+++ b/arch/arc/kernel/irq.c
@@ -8,116 +8,10 @@
*/

#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/irqdomain.h>
#include <linux/irqchip.h>
-#include "../../drivers/irqchip/irqchip.h"
-#include <asm/sections.h>
-#include <asm/irq.h>
#include <asm/mach_desc.h>

/*
- * Early Hardware specific Interrupt setup
- * -Platform independent, needed for each CPU (not foldable into init_IRQ)
- * -Called very early (start_kernel -> setup_arch -> setup_processor)
- *
- * what it does ?
- * -Optionally, setup the High priority Interrupts as Level 2 IRQs
- */
-void arc_init_IRQ(void)
-{
- int level_mask = 0;
-
- /* setup any high priority Interrupts (Level2 in ARCompact jargon) */
- level_mask |= IS_ENABLED(CONFIG_ARC_IRQ3_LV2) << 3;
- level_mask |= IS_ENABLED(CONFIG_ARC_IRQ5_LV2) << 5;
- level_mask |= IS_ENABLED(CONFIG_ARC_IRQ6_LV2) << 6;
-
- /*
- * Write to register, even if no LV2 IRQs configured to reset it
- * in case bootloader had mucked with it
- */
- write_aux_reg(AUX_IRQ_LEV, level_mask);
-
- if (level_mask)
- pr_info("Level-2 interrupts bitset %x\n", level_mask);
-}
-
-/*
- * 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_irq_mask(struct irq_data *data)
-{
- unsigned int ienb;
-
- ienb = read_aux_reg(AUX_IENABLE);
- ienb &= ~(1 << data->irq);
- write_aux_reg(AUX_IENABLE, ienb);
-}
-
-static void arc_irq_unmask(struct irq_data *data)
-{
- unsigned int ienb;
-
- ienb = read_aux_reg(AUX_IENABLE);
- ienb |= (1 << data->irq);
- write_aux_reg(AUX_IENABLE, ienb);
-}
-
-static struct irq_chip onchip_intc = {
- .name = "ARC In-core Intc",
- .irq_mask = arc_irq_mask,
- .irq_unmask = arc_irq_unmask,
-};
-
-static int arc_intc_domain_map(struct irq_domain *d, unsigned int irq,
- irq_hw_number_t hw)
-{
- if (irq == TIMER0_IRQ)
- irq_set_chip_and_handler(irq, &onchip_intc, handle_percpu_irq);
- else
- irq_set_chip_and_handler(irq, &onchip_intc, handle_level_irq);
-
- return 0;
-}
-
-static const struct irq_domain_ops arc_intc_domain_ops = {
- .xlate = irq_domain_xlate_onecell,
- .map = arc_intc_domain_map,
-};
-
-static struct irq_domain *root_domain;
-
-static int __init
-init_onchip_IRQ(struct device_node *intc, struct device_node *parent)
-{
- if (parent)
- panic("DeviceTree incore intc not a root irq controller\n");
-
- root_domain = irq_domain_add_legacy(intc, NR_CPU_IRQS, 0, 0,
- &arc_intc_domain_ops, NULL);
-
- if (!root_domain)
- panic("root irq domain not avail\n");
-
- /* with this we don't need to export root_domain */
- irq_set_default_host(root_domain);
-
- return 0;
-}
-
-IRQCHIP_DECLARE(arc_intc, "snps,arc700-intc", init_onchip_IRQ);
-
-/*
* Late Interrupt system init called from start_kernel for Boot CPU only
*
* Since slab must already be initialized, platforms can start doing any
@@ -178,107 +72,3 @@ void arc_request_percpu_irq(int irq, int cpu,

enable_percpu_irq(irq, 0);
}
-
-/*
- * arch_local_irq_enable - Enable interrupts.
- *
- * 1. Explicitly called to re-enable interrupts
- * 2. Implicitly called from spin_unlock_irq, write_unlock_irq etc
- * which maybe in hard ISR itself
- *
- * Semantics of this function change depending on where it is called from:
- *
- * -If called from hard-ISR, it must not invert interrupt priorities
- * e.g. suppose TIMER is high priority (Level 2) IRQ
- * Time hard-ISR, timer_interrupt( ) calls spin_unlock_irq several times.
- * Here local_irq_enable( ) shd not re-enable lower priority interrupts
- * -If called from soft-ISR, it must re-enable all interrupts
- * soft ISR are low prioity jobs which can be very slow, thus all IRQs
- * must be enabled while they run.
- * Now hardware context wise we may still be in L2 ISR (not done rtie)
- * still we must re-enable both L1 and L2 IRQs
- * Another twist is prev scenario with flow being
- * L1 ISR ==> interrupted by L2 ISR ==> L2 soft ISR
- * here we must not re-enable Ll as prev Ll Interrupt's h/w context will get
- * over-written (this is deficiency in ARC700 Interrupt mechanism)
- */
-
-#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS /* Complex version for 2 IRQ levels */
-
-void arch_local_irq_enable(void)
-{
-
- unsigned long flags;
- flags = arch_local_save_flags();
-
- /* Allow both L1 and L2 at the onset */
- flags |= (STATUS_E1_MASK | STATUS_E2_MASK);
-
- /* Called from hard ISR (between irq_enter and irq_exit) */
- if (in_irq()) {
-
- /* If in L2 ISR, don't re-enable any further IRQs as this can
- * cause IRQ priorities to get upside down. e.g. it could allow
- * L1 be taken while in L2 hard ISR which is wrong not only in
- * theory, it can also cause the dreaded L1-L2-L1 scenario
- */
- if (flags & STATUS_A2_MASK)
- flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK);
-
- /* Even if in L1 ISR, allowe Higher prio L2 IRQs */
- else if (flags & STATUS_A1_MASK)
- flags &= ~(STATUS_E1_MASK);
- }
-
- /* called from soft IRQ, ideally we want to re-enable all levels */
-
- else if (in_softirq()) {
-
- /* However if this is case of L1 interrupted by L2,
- * re-enabling both may cause whaco L1-L2-L1 scenario
- * because ARC700 allows level 1 to interrupt an active L2 ISR
- * Thus we disable both
- * However some code, executing in soft ISR wants some IRQs
- * to be enabled so we re-enable L2 only
- *
- * How do we determine L1 intr by L2
- * -A2 is set (means in L2 ISR)
- * -E1 is set in this ISR's pt_regs->status32 which is
- * saved copy of status32_l2 when l2 ISR happened
- */
- struct pt_regs *pt = get_irq_regs();
- if ((flags & STATUS_A2_MASK) && pt &&
- (pt->status32 & STATUS_A1_MASK)) {
- /*flags &= ~(STATUS_E1_MASK | STATUS_E2_MASK); */
- flags &= ~(STATUS_E1_MASK);
- }
- }
-
- arch_local_irq_restore(flags);
-}
-
-#else /* ! CONFIG_ARC_COMPACT_IRQ_LEVELS */
-
-/*
- * Simpler version for only 1 level of interrupt
- * Here we only Worry about Level 1 Bits
- */
-void arch_local_irq_enable(void)
-{
- unsigned long flags;
-
- /*
- * ARC IDE Drivers tries to re-enable interrupts from hard-isr
- * context which is simply wrong
- */
- if (in_irq()) {
- WARN_ONCE(1, "IRQ enabled from hard-isr");
- return;
- }
-
- flags = arch_local_save_flags();
- flags |= (STATUS_E1_MASK | STATUS_E2_MASK);
- arch_local_irq_restore(flags);
-}
-#endif
-EXPORT_SYMBOL(arch_local_irq_enable);
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index e095c557afdd..b5426babd3c8 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -166,8 +166,7 @@ void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp)
* [L] ZOL loop inhibited to begin with - cleared by a LP insn
* Interrupts enabled
*/
- regs->status32 = STATUS_U_MASK | STATUS_L_MASK |
- STATUS_E1_MASK | STATUS_E2_MASK;
+ regs->status32 = STATUS_U_MASK | STATUS_L_MASK | STATUS_IE_MASK;

/* bogus seed values for debugging */
regs->lp_start = 0x10;
--
1.9.1

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