linux/arch/tile/include/asm/irqflags.h
Chris Metcalf bc1a298f4e tile: support CONFIG_PREEMPT
This change adds support for CONFIG_PREEMPT (full kernel preemption).
In addition to the core support, this change includes a number
of places where we fix up uses of smp_processor_id() and per-cpu
variables.  I also eliminate the PAGE_HOME_HERE and PAGE_HOME_UNKNOWN
values for page homing, as it turns out they weren't being used.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-08-13 16:26:01 -04:00

312 lines
11 KiB
C

/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
*
* 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, version 2.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*/
#ifndef _ASM_TILE_IRQFLAGS_H
#define _ASM_TILE_IRQFLAGS_H
#include <arch/interrupts.h>
#include <arch/chip.h>
/*
* The set of interrupts we want to allow when interrupts are nominally
* disabled. The remainder are effectively "NMI" interrupts from
* the point of view of the generic Linux code. Note that synchronous
* interrupts (aka "non-queued") are not blocked by the mask in any case.
*/
#define LINUX_MASKABLE_INTERRUPTS \
(~((_AC(1,ULL) << INT_PERF_COUNT) | (_AC(1,ULL) << INT_AUX_PERF_COUNT)))
#if CHIP_HAS_SPLIT_INTR_MASK()
/* The same macro, but for the two 32-bit SPRs separately. */
#define LINUX_MASKABLE_INTERRUPTS_LO (-1)
#define LINUX_MASKABLE_INTERRUPTS_HI \
(~((1 << (INT_PERF_COUNT - 32)) | (1 << (INT_AUX_PERF_COUNT - 32))))
#endif
#ifndef __ASSEMBLY__
/* NOTE: we can't include <linux/percpu.h> due to #include dependencies. */
#include <asm/percpu.h>
#include <arch/spr_def.h>
/*
* Set and clear kernel interrupt masks.
*
* NOTE: __insn_mtspr() is a compiler builtin marked as a memory
* clobber. We rely on it being equivalent to a compiler barrier in
* this code since arch_local_irq_save() and friends must act as
* compiler barriers. This compiler semantic is baked into enough
* places that the compiler will maintain it going forward.
*/
#if CHIP_HAS_SPLIT_INTR_MASK()
#if INT_PERF_COUNT < 32 || INT_AUX_PERF_COUNT < 32 || INT_MEM_ERROR >= 32
# error Fix assumptions about which word various interrupts are in
#endif
#define interrupt_mask_set(n) do { \
int __n = (n); \
int __mask = 1 << (__n & 0x1f); \
if (__n < 32) \
__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_0, __mask); \
else \
__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_1, __mask); \
} while (0)
#define interrupt_mask_reset(n) do { \
int __n = (n); \
int __mask = 1 << (__n & 0x1f); \
if (__n < 32) \
__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_0, __mask); \
else \
__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_1, __mask); \
} while (0)
#define interrupt_mask_check(n) ({ \
int __n = (n); \
(((__n < 32) ? \
__insn_mfspr(SPR_INTERRUPT_MASK_K_0) : \
__insn_mfspr(SPR_INTERRUPT_MASK_K_1)) \
>> (__n & 0x1f)) & 1; \
})
#define interrupt_mask_set_mask(mask) do { \
unsigned long long __m = (mask); \
__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_0, (unsigned long)(__m)); \
__insn_mtspr(SPR_INTERRUPT_MASK_SET_K_1, (unsigned long)(__m>>32)); \
} while (0)
#define interrupt_mask_reset_mask(mask) do { \
unsigned long long __m = (mask); \
__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_0, (unsigned long)(__m)); \
__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K_1, (unsigned long)(__m>>32)); \
} while (0)
#define interrupt_mask_save_mask() \
(__insn_mfspr(SPR_INTERRUPT_MASK_SET_K_0) | \
(((unsigned long long)__insn_mfspr(SPR_INTERRUPT_MASK_SET_K_1))<<32))
#define interrupt_mask_restore_mask(mask) do { \
unsigned long long __m = (mask); \
__insn_mtspr(SPR_INTERRUPT_MASK_K_0, (unsigned long)(__m)); \
__insn_mtspr(SPR_INTERRUPT_MASK_K_1, (unsigned long)(__m>>32)); \
} while (0)
#else
#define interrupt_mask_set(n) \
__insn_mtspr(SPR_INTERRUPT_MASK_SET_K, (1UL << (n)))
#define interrupt_mask_reset(n) \
__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K, (1UL << (n)))
#define interrupt_mask_check(n) \
((__insn_mfspr(SPR_INTERRUPT_MASK_K) >> (n)) & 1)
#define interrupt_mask_set_mask(mask) \
__insn_mtspr(SPR_INTERRUPT_MASK_SET_K, (mask))
#define interrupt_mask_reset_mask(mask) \
__insn_mtspr(SPR_INTERRUPT_MASK_RESET_K, (mask))
#define interrupt_mask_save_mask() \
__insn_mfspr(SPR_INTERRUPT_MASK_K)
#define interrupt_mask_restore_mask(mask) \
__insn_mtspr(SPR_INTERRUPT_MASK_K, (mask))
#endif
/*
* The set of interrupts we want active if irqs are enabled.
* Note that in particular, the tile timer interrupt comes and goes
* from this set, since we have no other way to turn off the timer.
* Likewise, INTCTRL_K is removed and re-added during device
* interrupts, as is the the hardwall UDN_FIREWALL interrupt.
* We use a low bit (MEM_ERROR) as our sentinel value and make sure it
* is always claimed as an "active interrupt" so we can query that bit
* to know our current state.
*/
DECLARE_PER_CPU(unsigned long long, interrupts_enabled_mask);
#define INITIAL_INTERRUPTS_ENABLED (1ULL << INT_MEM_ERROR)
#ifdef CONFIG_DEBUG_PREEMPT
/* Due to inclusion issues, we can't rely on <linux/smp.h> here. */
extern unsigned int debug_smp_processor_id(void);
# define smp_processor_id() debug_smp_processor_id()
#endif
/* Disable interrupts. */
#define arch_local_irq_disable() \
interrupt_mask_set_mask(LINUX_MASKABLE_INTERRUPTS)
/* Disable all interrupts, including NMIs. */
#define arch_local_irq_disable_all() \
interrupt_mask_set_mask(-1ULL)
/*
* Read the set of maskable interrupts.
* We avoid the preemption warning here via __this_cpu_ptr since even
* if irqs are already enabled, it's harmless to read the wrong cpu's
* enabled mask.
*/
#define arch_local_irqs_enabled() \
(*__this_cpu_ptr(&interrupts_enabled_mask))
/* Re-enable all maskable interrupts. */
#define arch_local_irq_enable() \
interrupt_mask_reset_mask(arch_local_irqs_enabled())
/* Disable or enable interrupts based on flag argument. */
#define arch_local_irq_restore(disabled) do { \
if (disabled) \
arch_local_irq_disable(); \
else \
arch_local_irq_enable(); \
} while (0)
/* Return true if "flags" argument means interrupts are disabled. */
#define arch_irqs_disabled_flags(flags) ((flags) != 0)
/* Return true if interrupts are currently disabled. */
#define arch_irqs_disabled() interrupt_mask_check(INT_MEM_ERROR)
/* Save whether interrupts are currently disabled. */
#define arch_local_save_flags() arch_irqs_disabled()
/* Save whether interrupts are currently disabled, then disable them. */
#define arch_local_irq_save() ({ \
unsigned long __flags = arch_local_save_flags(); \
arch_local_irq_disable(); \
__flags; })
/* Prevent the given interrupt from being enabled next time we enable irqs. */
#define arch_local_irq_mask(interrupt) \
this_cpu_and(interrupts_enabled_mask, ~(1ULL << (interrupt)))
/* Prevent the given interrupt from being enabled immediately. */
#define arch_local_irq_mask_now(interrupt) do { \
arch_local_irq_mask(interrupt); \
interrupt_mask_set(interrupt); \
} while (0)
/* Allow the given interrupt to be enabled next time we enable irqs. */
#define arch_local_irq_unmask(interrupt) \
this_cpu_or(interrupts_enabled_mask, (1ULL << (interrupt)))
/* Allow the given interrupt to be enabled immediately, if !irqs_disabled. */
#define arch_local_irq_unmask_now(interrupt) do { \
arch_local_irq_unmask(interrupt); \
if (!irqs_disabled()) \
interrupt_mask_reset(interrupt); \
} while (0)
#else /* __ASSEMBLY__ */
/* We provide a somewhat more restricted set for assembly. */
#ifdef __tilegx__
#if INT_MEM_ERROR != 0
# error Fix IRQS_DISABLED() macro
#endif
/* Return 0 or 1 to indicate whether interrupts are currently disabled. */
#define IRQS_DISABLED(tmp) \
mfspr tmp, SPR_INTERRUPT_MASK_K; \
andi tmp, tmp, 1
/* Load up a pointer to &interrupts_enabled_mask. */
#define GET_INTERRUPTS_ENABLED_MASK_PTR(reg) \
moveli reg, hw2_last(interrupts_enabled_mask); \
shl16insli reg, reg, hw1(interrupts_enabled_mask); \
shl16insli reg, reg, hw0(interrupts_enabled_mask); \
add reg, reg, tp
/* Disable interrupts. */
#define IRQ_DISABLE(tmp0, tmp1) \
moveli tmp0, hw2_last(LINUX_MASKABLE_INTERRUPTS); \
shl16insli tmp0, tmp0, hw1(LINUX_MASKABLE_INTERRUPTS); \
shl16insli tmp0, tmp0, hw0(LINUX_MASKABLE_INTERRUPTS); \
mtspr SPR_INTERRUPT_MASK_SET_K, tmp0
/* Disable ALL synchronous interrupts (used by NMI entry). */
#define IRQ_DISABLE_ALL(tmp) \
movei tmp, -1; \
mtspr SPR_INTERRUPT_MASK_SET_K, tmp
/* Enable interrupts. */
#define IRQ_ENABLE_LOAD(tmp0, tmp1) \
GET_INTERRUPTS_ENABLED_MASK_PTR(tmp0); \
ld tmp0, tmp0
#define IRQ_ENABLE_APPLY(tmp0, tmp1) \
mtspr SPR_INTERRUPT_MASK_RESET_K, tmp0
#else /* !__tilegx__ */
/*
* Return 0 or 1 to indicate whether interrupts are currently disabled.
* Note that it's important that we use a bit from the "low" mask word,
* since when we are enabling, that is the word we write first, so if we
* are interrupted after only writing half of the mask, the interrupt
* handler will correctly observe that we have interrupts enabled, and
* will enable interrupts itself on return from the interrupt handler
* (making the original code's write of the "high" mask word idempotent).
*/
#define IRQS_DISABLED(tmp) \
mfspr tmp, SPR_INTERRUPT_MASK_K_0; \
shri tmp, tmp, INT_MEM_ERROR; \
andi tmp, tmp, 1
/* Load up a pointer to &interrupts_enabled_mask. */
#define GET_INTERRUPTS_ENABLED_MASK_PTR(reg) \
moveli reg, lo16(interrupts_enabled_mask); \
auli reg, reg, ha16(interrupts_enabled_mask); \
add reg, reg, tp
/* Disable interrupts. */
#define IRQ_DISABLE(tmp0, tmp1) \
{ \
movei tmp0, LINUX_MASKABLE_INTERRUPTS_LO; \
moveli tmp1, lo16(LINUX_MASKABLE_INTERRUPTS_HI) \
}; \
{ \
mtspr SPR_INTERRUPT_MASK_SET_K_0, tmp0; \
auli tmp1, tmp1, ha16(LINUX_MASKABLE_INTERRUPTS_HI) \
}; \
mtspr SPR_INTERRUPT_MASK_SET_K_1, tmp1
/* Disable ALL synchronous interrupts (used by NMI entry). */
#define IRQ_DISABLE_ALL(tmp) \
movei tmp, -1; \
mtspr SPR_INTERRUPT_MASK_SET_K_0, tmp; \
mtspr SPR_INTERRUPT_MASK_SET_K_1, tmp
/* Enable interrupts. */
#define IRQ_ENABLE_LOAD(tmp0, tmp1) \
GET_INTERRUPTS_ENABLED_MASK_PTR(tmp0); \
{ \
lw tmp0, tmp0; \
addi tmp1, tmp0, 4 \
}; \
lw tmp1, tmp1
#define IRQ_ENABLE_APPLY(tmp0, tmp1) \
mtspr SPR_INTERRUPT_MASK_RESET_K_0, tmp0; \
mtspr SPR_INTERRUPT_MASK_RESET_K_1, tmp1
#endif
#define IRQ_ENABLE(tmp0, tmp1) \
IRQ_ENABLE_LOAD(tmp0, tmp1); \
IRQ_ENABLE_APPLY(tmp0, tmp1)
/*
* Do the CPU's IRQ-state tracing from assembly code. We call a
* C function, but almost everywhere we do, we don't mind clobbering
* all the caller-saved registers.
*/
#ifdef CONFIG_TRACE_IRQFLAGS
# define TRACE_IRQS_ON jal trace_hardirqs_on
# define TRACE_IRQS_OFF jal trace_hardirqs_off
#else
# define TRACE_IRQS_ON
# define TRACE_IRQS_OFF
#endif
#endif /* __ASSEMBLY__ */
#endif /* _ASM_TILE_IRQFLAGS_H */