| /* |
| * 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. |
| * |
| * 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) |
| * |
| * Vineetg: July 2009 |
| * -Improved xchg implementation by tweaking reg contraints (+r) so that |
| * unnecessary glue code is not generated |
| * |
| * Vineetg: Mar 2009 (Critical look at file) |
| * -Improved local_irq_save() and friends to not use r20 (CALLLEE Saved) |
| * but let the compiler do register allocation |
| * -[mask|unmask]_interrupt( ) need not do inline IRQ disable as caller holds |
| * spin_lock_irqsave( ) before invoking them |
| * |
| * Vineetg: Mar 2009 (Supporting 2 levels of Interrupts) |
| * -irqs_enabled( ) need to consider both L1 and L2 |
| * -local_irq_enable shd be cognizant of current IRQ state |
| * and must not re-enable lower priorty IRQs |
| * It is lot more involved now and needs to be written in "C" |
| * |
| * Vineetg: Feb 2009 |
| * -schedular hook prepare_arch_switch( ) is now macro instead of inline func |
| * so that builtin_ret_addr( ) can correctly identify the caller of schdule() |
| * |
| * Vineetg: Oct 3rd 2008 |
| * -Got rid of evil cli()/sti() from architecture code |
| * |
| * Amit Bhor, Sameer Dhavale: Codito Technologies 2004 |
| */ |
| |
| #ifndef __ASM_ARC_SYSTEM_H |
| #define __ASM_ARC_SYSTEM_H |
| |
| #include <asm/ptrace.h> |
| |
| #ifndef __ASSEMBLY__ |
| |
| #ifdef __KERNEL__ |
| |
| /****************************************************************** |
| * Atomically Exchange memory with a register |
| ******************************************************************/ |
| |
| static inline unsigned long __xchg_32(unsigned long with, volatile void *ptr) |
| { |
| /* On ARC700, "ex" is inherently atomic so don't need IRQ disabling */ |
| |
| __asm__ __volatile__ ( |
| " ex %0, [%1]" |
| : "+r" (with) |
| : "r"(ptr) |
| : "memory" ); |
| |
| return (with); |
| } |
| |
| /* This function doesn't exist, so that for non supported xchg (64 bits) |
| * we will get link errors. |
| * shamelessly copied from MIPS |
| */ |
| extern void __xchg_bad_pointer(void); |
| |
| static inline unsigned long __xchg(unsigned long val, volatile void *ptr, |
| int size) |
| { |
| switch (size) { |
| case 4: |
| return __xchg_32(val, ptr); |
| // TODO-vineetg: 64 bit atomic xchg go here |
| } |
| __xchg_bad_pointer(); |
| return val; |
| } |
| |
| #define xchg(ptr, with) \ |
| ((__typeof__ (*(ptr)))__xchg ((unsigned long)(with), (ptr), sizeof (*(ptr)))) |
| |
| /****************************************************************** |
| * Barriers |
| ******************************************************************/ |
| |
| //TODO-vineetg: Need to see what this does, dont we need sync anywhere |
| #define mb() __asm__ __volatile__ ("" : : : "memory") |
| #define rmb() mb() |
| #define wmb() mb() |
| #define set_mb(var, value) do { var = value; mb(); } while (0) |
| #define set_wmb(var, value) do { var = value; wmb(); } while (0) |
| |
| /* TODO-vineetg verify the correctness of macros here */ |
| #ifdef CONFIG_SMP |
| #define smp_mb() mb() |
| #define smp_rmb() rmb() |
| #define smp_wmb() wmb() |
| #else |
| #define smp_mb() barrier() |
| #define smp_rmb() barrier() |
| #define smp_wmb() barrier() |
| #endif |
| |
| #define smp_read_barrier_depends() do { } while(0) |
| |
| /****************************************************************** |
| * Arch Depenedent Context Switch Macro called by sched |
| * This in turn calls the regfile switching macro __switch_to ( ) |
| ******************************************************************/ |
| struct task_struct; // to prevent cyclic dependencies |
| |
| /* switch_to macro based on the ARM implementaion */ |
| extern struct task_struct *__switch_to(struct task_struct *prev, |
| struct task_struct *next); |
| |
| #ifdef CONFIG_ARCH_ARC_FPU |
| |
| #define HW_BUG_101581 |
| |
| #ifdef HW_BUG_101581 |
| |
| extern void fpu_save_restore(struct task_struct *prev, struct task_struct *next); |
| |
| #define ARC_FPU_PREV(p,n) fpu_save_restore(p,n) |
| #define ARC_FPU_NEXT(t) |
| |
| #else /* !HW_BUG_101581 */ |
| |
| extern void inline fpu_save(struct task_struct *tsk); |
| extern void inline fpu_restore(struct task_struct *tsk); |
| |
| #define ARC_FPU_PREV(p,n) fpu_save(p) |
| #define ARC_FPU_NEXT(t) fpu_restore(t) |
| |
| #endif /* !HW_BUG_101581 */ |
| |
| #else /* !CONFIG_ARCH_ARC_FPU */ |
| |
| #define ARC_FPU_PREV(p,n) |
| #define ARC_FPU_NEXT(t) |
| |
| #endif /* !CONFIG_ARCH_ARC_FPU */ |
| |
| #define switch_to(prev, next, last) \ |
| { \ |
| do { \ |
| ARC_FPU_PREV(prev, next); \ |
| last = __switch_to( prev, next); \ |
| ARC_FPU_NEXT(next); \ |
| mb(); \ |
| \ |
| }while (0); \ |
| } |
| |
| /* Hook into Schedular to be invoked prior to Context Switch |
| * -If ARC H/W profiling enabled it does some stuff |
| * -If event logging enabled it takes a event snapshot |
| * |
| * Having a funtion would have been cleaner but to get the correct caller |
| * (from __builtin_return_address) it needs to be inline |
| */ |
| |
| /* Things to do for event logging prior to Context switch */ |
| #ifdef CONFIG_ARC_DBG_EVENT_TIMELINE |
| #define PREP_ARCH_SWITCH_ACT1(next) \ |
| do { \ |
| if (next->mm) \ |
| take_snap(SNAP_PRE_CTXSW_2_U, \ |
| (unsigned int) __builtin_return_address(0), \ |
| current_thread_info()->preempt_count); \ |
| else \ |
| take_snap(SNAP_PRE_CTXSW_2_K, \ |
| (unsigned int) __builtin_return_address(0), \ |
| current_thread_info()->preempt_count); \ |
| } \ |
| while(0) |
| #else |
| #define PREP_ARCH_SWITCH_ACT1(next) |
| #endif |
| |
| |
| /* Things to do for hardware based profiling prior to Context Switch */ |
| #ifdef CONFIG_ARC_PROFILING |
| extern void arc_ctx_callout(struct task_struct *next); |
| #define PREP_ARCH_SWITCH_ACT2(next) arc_ctx_callout(next) |
| #else |
| #define PREP_ARCH_SWITCH_ACT2(next) |
| #endif |
| |
| /* This def is the one used by schedular */ |
| #define prepare_arch_switch(next) \ |
| do { \ |
| PREP_ARCH_SWITCH_ACT1(next); \ |
| PREP_ARCH_SWITCH_ACT2(next); \ |
| } \ |
| while(0) |
| |
| |
| /****************************************************************** |
| * Miscll stuff |
| ******************************************************************/ |
| |
| /* |
| * On SMP systems, when the scheduler does migration-cost autodetection, |
| * it needs a way to flush as much of the CPU's caches as possible. |
| * |
| * TODO: fill this in! |
| */ |
| static inline void sched_cacheflush(void) |
| { |
| } |
| |
| static inline unsigned long arch_align_stack(unsigned long sp) |
| { |
| //unsigned long orig_sp = sp; |
| |
| #ifdef CONFIG_ARCH_ARC_SPACE_RND |
| /* ELF loader sets this flag way early. |
| * So no need to check for multiple things like |
| * !(current->personality & ADDR_NO_RANDOMIZE) |
| * randomize_va_space |
| */ |
| if (current->flags & PF_RANDOMIZE) { |
| |
| /* Stack grows down for ARC */ |
| sp -= get_random_int() & ~PAGE_MASK; |
| } |
| #endif |
| |
| sp &= ~0xF; // always align stack to 16 bytes |
| |
| //printk("RAND: SP orig %x rnd %x\n", orig_sp, sp); |
| return sp; |
| } |
| |
| /****************************************************************** |
| * Piggyback stuff |
| * #defines/headers to be made avail to rest of code w/o explicit include |
| * e.g. to call event log macros from any kernel file w/o including |
| * eventlog.h in that file |
| ******************************************************************/ |
| |
| |
| #include <plat_memmap.h> // Peripherals Memory Map |
| #include <asm/event-log.h> // event log from "C" |
| |
| void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs); |
| void raw_printk(const char *str, unsigned int num); |
| void raw_printk5(const char *str, unsigned int n1, unsigned int n2, |
| unsigned int n3, unsigned int n4); |
| |
| /****************************************************************** |
| * printk calls in __init code, so that their literal strings go into |
| * .init.rodata (which gets reclaimed) instead of in .rodata |
| ******************************************************************/ |
| #define INIT_PRINT 0 |
| |
| #if (INIT_PRINT == 2) |
| #define printk_init(fmt, args...) printk(fmt, ## args) |
| #elif (INIT_PRINT == 1) |
| #define printk_init(fmt, args...) |
| #else |
| #define printk_init(fmt, args...) \ |
| ({ \ |
| static const __initconst char __fmt[] = fmt; \ |
| printk(__fmt, ## args); \ |
| }) |
| #endif |
| |
| #endif /*__KERNEL__*/ |
| |
| #else /* !__ASSEMBLY__ */ |
| |
| #include <asm/event-log.h> // event log from Assembly |
| |
| |
| #endif /* __ASSEMBLY__ */ |
| |
| |
| #endif /* ASM_ARC_SYSTEM_H */ |
