From: Vineet Gupta Date: Fri, 18 Jan 2013 09:42:16 +0000 (+0530) Subject: ARC: irqflags - Interrupt enabling/disabling at in-core intc X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=ac4c244d4e5d914f9a5642cdcc03b18780e55dbc;p=linux-beck.git ARC: irqflags - Interrupt enabling/disabling at in-core intc ARC700 has an in-core intc which provides 2 priorities (a.k.a.) "levels" of interrupts (per IRQ) hencforth referred to as L1/L2 interrupts. CPU flags register STATUS32 has Interrupt Enable bits per level (E1/E2) to globally enable (or disable) all IRQs at a level. Hence the implementation of arch_local_irq_{save,restore,enable,disable}( ) The STATUS32 reg can be r/w only using the AUX Interface of ARC, hence the use of LR/SR instructions. Further, E1/E2 bits in there can only be updated using the FLAG insn. The intc supports 32 interrupts - and per IRQ enabling is controlled by a bit in the AUX_IENABLE register, hence the implmentation of arch_{,un}mask_irq( ) routines. Signed-off-by: Vineet Gupta Cc: Thomas Gleixner --- diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h new file mode 100644 index 000000000000..8ca8faf4b80e --- /dev/null +++ b/arch/arc/include/asm/arcregs.h @@ -0,0 +1,114 @@ +/* + * 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_ARCREGS_H +#define _ASM_ARC_ARCREGS_H + +#ifdef __KERNEL__ + +/* status32 Bits Positions */ +#define STATUS_H_BIT 0 /* CPU Halted */ +#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_AE_BIT 5 /* Exception active */ +#define STATUS_DE_BIT 6 /* PC is in delay slot */ +#define STATUS_U_BIT 7 /* User/Kernel mode */ +#define STATUS_L_BIT 12 /* Loop inhibit */ + +/* These masks correspond to the status word(STATUS_32) bits */ +#define STATUS_H_MASK (1< + +#ifndef __ASSEMBLY__ + +/****************************************************************** + * IRQ Control Macros + ******************************************************************/ + +/* + * 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)) + : "cc"); + + return flags; +} + +/* + * restore saved IRQ state + */ +static inline void arch_local_irq_restore(unsigned long flags) +{ + + __asm__ __volatile__( + " flag %0 \n" + : + : "r"(flags)); +} + +/* + * 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))); +} + +/* + * save IRQ state + */ +static inline long arch_local_save_flags(void) +{ + unsigned long temp; + + __asm__ __volatile__( + " lr %0, [status32] \n" + : "=&r"(temp)); + + return temp; +} + +/* + * Query IRQ state + */ +static inline int arch_irqs_disabled_flags(unsigned long flags) +{ + return !(flags & (STATUS_E1_MASK)); +} + +static inline int arch_irqs_disabled(void) +{ + return arch_irqs_disabled_flags(arch_local_save_flags()); +} + +static inline void arch_mask_irq(unsigned int irq) +{ + unsigned int ienb; + + ienb = read_aux_reg(AUX_IENABLE); + ienb &= ~(1 << irq); + write_aux_reg(AUX_IENABLE, ienb); +} + +static inline void arch_unmask_irq(unsigned int irq) +{ + unsigned int ienb; + + ienb = read_aux_reg(AUX_IENABLE); + ienb |= (1 << irq); + write_aux_reg(AUX_IENABLE, ienb); +} + +#else + +.macro IRQ_DISABLE scratch + lr \scratch, [status32] + bic \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK) + flag \scratch +.endm + +.macro IRQ_DISABLE_SAVE scratch, save + lr \scratch, [status32] + mov \save, \scratch /* Make a copy */ + bic \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK) + flag \scratch +.endm + +.macro IRQ_ENABLE scratch + lr \scratch, [status32] + or \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK) + flag \scratch +.endm + +#endif /* __ASSEMBLY__ */ + +#endif /* KERNEL */ + +#endif diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c new file mode 100644 index 000000000000..c4e9b25d305f --- /dev/null +++ b/arch/arc/kernel/irq.c @@ -0,0 +1,32 @@ +/* + * 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 +#include +#include +#include + +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); +} +EXPORT_SYMBOL(arch_local_irq_enable);