diff options
author | Vineet Gupta <vgupta@synopsys.com> | 2015-03-05 16:43:56 +0300 |
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committer | Vineet Gupta <vgupta@synopsys.com> | 2015-06-19 15:39:40 +0300 |
commit | 5793e273a134331d05ed904e5be3b31ccfca54c1 (patch) | |
tree | d615c70600502c888108e6c99fa365c53c68bd9d /arch/arc/kernel | |
parent | 6ffb9c8c5f59a50779109e8b0a2e1bdd4b9be5c5 (diff) | |
download | linux-5793e273a134331d05ed904e5be3b31ccfca54c1.tar.xz |
ARC: intc: split into ARCompact ISA specific, common bits
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/kernel')
-rw-r--r-- | arch/arc/kernel/Makefile | 2 | ||||
-rw-r--r-- | arch/arc/kernel/intc-compact.c | 226 | ||||
-rw-r--r-- | arch/arc/kernel/irq.c | 210 | ||||
-rw-r--r-- | arch/arc/kernel/process.c | 3 |
4 files changed, 228 insertions, 213 deletions
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..fcdddb631766 --- /dev/null +++ b/arch/arc/kernel/intc-compact.c @@ -0,0 +1,226 @@ +/* + * 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) +{ + /* + * 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 = 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; |