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-rw-r--r--kernel/arch/arc/include/asm/processor.h135
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diff --git a/kernel/arch/arc/include/asm/processor.h b/kernel/arch/arc/include/asm/processor.h
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+++ b/kernel/arch/arc/include/asm/processor.h
@@ -0,0 +1,135 @@
+/*
+ * 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 2009
+ * -Implemented task_pt_regs( )
+ *
+ * Amit Bhor, Sameer Dhavale, Ashwin Chaugule: Codito Technologies 2004
+ */
+
+#ifndef __ASM_ARC_PROCESSOR_H
+#define __ASM_ARC_PROCESSOR_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm/ptrace.h>
+
+#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
+/* These DPFP regs need to be saved/restored across ctx-sw */
+struct arc_fpu {
+ struct {
+ unsigned int l, h;
+ } aux_dpfp[2];
+};
+#endif
+
+/* Arch specific stuff which needs to be saved per task.
+ * However these items are not so important so as to earn a place in
+ * struct thread_info
+ */
+struct thread_struct {
+ unsigned long ksp; /* kernel mode stack pointer */
+ unsigned long callee_reg; /* pointer to callee regs */
+ unsigned long fault_address; /* dbls as brkpt holder as well */
+#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
+ struct arc_fpu fpu;
+#endif
+};
+
+#define INIT_THREAD { \
+ .ksp = sizeof(init_stack) + (unsigned long) init_stack, \
+}
+
+/* Forward declaration, a strange C thing */
+struct task_struct;
+
+#define task_pt_regs(p) \
+ ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1)
+
+/* Free all resources held by a thread */
+#define release_thread(thread) do { } while (0)
+
+/*
+ * A lot of busy-wait loops in SMP are based off of non-volatile data otherwise
+ * get optimised away by gcc
+ */
+#ifdef CONFIG_SMP
+#define cpu_relax() __asm__ __volatile__ ("" : : : "memory")
+#else
+#define cpu_relax() do { } while (0)
+#endif
+
+#define cpu_relax_lowlatency() cpu_relax()
+
+#define copy_segments(tsk, mm) do { } while (0)
+#define release_segments(mm) do { } while (0)
+
+#define KSTK_EIP(tsk) (task_pt_regs(tsk)->ret)
+#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp)
+
+/*
+ * Where abouts of Task's sp, fp, blink when it was last seen in kernel mode.
+ * Look in process.c for details of kernel stack layout
+ */
+#define TSK_K_ESP(tsk) (tsk->thread.ksp)
+
+#define TSK_K_REG(tsk, off) (*((unsigned int *)(TSK_K_ESP(tsk) + \
+ sizeof(struct callee_regs) + off)))
+
+#define TSK_K_BLINK(tsk) TSK_K_REG(tsk, 4)
+#define TSK_K_FP(tsk) TSK_K_REG(tsk, 0)
+
+#define thread_saved_pc(tsk) TSK_K_BLINK(tsk)
+
+extern void start_thread(struct pt_regs * regs, unsigned long pc,
+ unsigned long usp);
+
+extern unsigned int get_wchan(struct task_struct *p);
+
+/*
+ * Default implementation of macro that returns current
+ * instruction pointer ("program counter").
+ * Should the PC register be read instead ? This macro does not seem to
+ * be used in many places so this wont be all that bad.
+ */
+#define current_text_addr() ({ __label__ _l; _l: &&_l; })
+
+#endif /* !__ASSEMBLY__ */
+
+/* Kernels Virtual memory area.
+ * Unlike other architectures(MIPS, sh, cris ) ARC 700 does not have a
+ * "kernel translated" region (like KSEG2 in MIPS). So we use a upper part
+ * of the translated bottom 2GB for kernel virtual memory and protect
+ * these pages from user accesses by disabling Ru, Eu and Wu.
+ */
+#define VMALLOC_SIZE (0x10000000) /* 256M */
+#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE)
+#define VMALLOC_END (PAGE_OFFSET)
+
+/* Most of the architectures seem to be keeping some kind of padding between
+ * userspace TASK_SIZE and PAGE_OFFSET. i.e TASK_SIZE != PAGE_OFFSET.
+ */
+#define USER_KERNEL_GUTTER 0x10000000
+
+/* User address space:
+ * On ARC700, CPU allows the entire lower half of 32 bit address space to be
+ * translated. Thus potentially 2G (0:0x7FFF_FFFF) could be User vaddr space.
+ * However we steal 256M for kernel addr (0x7000_0000:0x7FFF_FFFF) and another
+ * 256M (0x6000_0000:0x6FFF_FFFF) is gutter between user/kernel spaces
+ * Thus total User vaddr space is (0:0x5FFF_FFFF)
+ */
+#define TASK_SIZE (PAGE_OFFSET - VMALLOC_SIZE - USER_KERNEL_GUTTER)
+
+#define STACK_TOP TASK_SIZE
+#define STACK_TOP_MAX STACK_TOP
+
+/* This decides where the kernel will search for a free chunk of vm
+ * space during mmap's.
+ */
+#define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
+
+#endif /* __ASM_ARC_PROCESSOR_H */