root/arch/sh/include/asm/processor_32.h

INCLUDED FROM

DEFINITIONS

1. disable_fpu
2. enable_fpu
3. show_code
4. prefetch
5. prefetchw

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * include/asm-sh/processor.h
   4  *
   5  * Copyright (C) 1999, 2000  Niibe Yutaka
   6  * Copyright (C) 2002, 2003  Paul Mundt
   7  */
   8 
   9 #ifndef __ASM_SH_PROCESSOR_32_H
  10 #define __ASM_SH_PROCESSOR_32_H
  11 #ifdef __KERNEL__
  12 
  13 #include <linux/compiler.h>
  14 #include <linux/linkage.h>
  15 #include <asm/page.h>
  16 #include <asm/types.h>
  17 #include <asm/hw_breakpoint.h>
  18 
  19 /* Core Processor Version Register */
  20 #define CCN_PVR         0xff000030
  21 #define CCN_CVR         0xff000040
  22 #define CCN_PRR         0xff000044
  23 
  24 /*
  25  * User space process size: 2GB.
  26  *
  27  * Since SH7709 and SH7750 have "area 7", we can't use 0x7c000000--0x7fffffff
  28  */
  29 #define TASK_SIZE       0x7c000000UL
  30 
  31 #define STACK_TOP       TASK_SIZE
  32 #define STACK_TOP_MAX   STACK_TOP
  33 
  34 /* This decides where the kernel will search for a free chunk of vm
  35  * space during mmap's.
  36  */
  37 #define TASK_UNMAPPED_BASE      PAGE_ALIGN(TASK_SIZE / 3)
  38 
  39 /*
  40  * Bit of SR register
  41  *
  42  * FD-bit:
  43  *     When it's set, it means the processor doesn't have right to use FPU,
  44  *     and it results exception when the floating operation is executed.
  45  *
  46  * IMASK-bit:
  47  *     Interrupt level mask
  48  */
  49 #define SR_DSP          0x00001000
  50 #define SR_IMASK        0x000000f0
  51 #define SR_FD           0x00008000
  52 #define SR_MD           0x40000000
  53 
  54 /*
  55  * DSP structure and data
  56  */
  57 struct sh_dsp_struct {
  58         unsigned long dsp_regs[14];
  59         long status;
  60 };
  61 
  62 /*
  63  * FPU structure and data
  64  */
  65 
  66 struct sh_fpu_hard_struct {
  67         unsigned long fp_regs[16];
  68         unsigned long xfp_regs[16];
  69         unsigned long fpscr;
  70         unsigned long fpul;
  71 
  72         long status; /* software status information */
  73 };
  74 
  75 /* Dummy fpu emulator  */
  76 struct sh_fpu_soft_struct {
  77         unsigned long fp_regs[16];
  78         unsigned long xfp_regs[16];
  79         unsigned long fpscr;
  80         unsigned long fpul;
  81 
  82         unsigned char lookahead;
  83         unsigned long entry_pc;
  84 };
  85 
  86 union thread_xstate {
  87         struct sh_fpu_hard_struct hardfpu;
  88         struct sh_fpu_soft_struct softfpu;
  89 };
  90 
  91 struct thread_struct {
  92         /* Saved registers when thread is descheduled */
  93         unsigned long sp;
  94         unsigned long pc;
  95 
  96         /* Various thread flags, see SH_THREAD_xxx */
  97         unsigned long flags;
  98 
  99         /* Save middle states of ptrace breakpoints */
 100         struct perf_event *ptrace_bps[HBP_NUM];
 101 
 102 #ifdef CONFIG_SH_DSP
 103         /* Dsp status information */
 104         struct sh_dsp_struct dsp_status;
 105 #endif
 106 
 107         /* Extended processor state */
 108         union thread_xstate *xstate;
 109 
 110         /*
 111          * fpu_counter contains the number of consecutive context switches
 112          * that the FPU is used. If this is over a threshold, the lazy fpu
 113          * saving becomes unlazy to save the trap. This is an unsigned char
 114          * so that after 256 times the counter wraps and the behavior turns
 115          * lazy again; this to deal with bursty apps that only use FPU for
 116          * a short time
 117          */
 118         unsigned char fpu_counter;
 119 };
 120 
 121 #define INIT_THREAD  {                                          \
 122         .sp = sizeof(init_stack) + (long) &init_stack,          \
 123         .flags = 0,                                             \
 124 }
 125 
 126 /* Forward declaration, a strange C thing */
 127 struct task_struct;
 128 
 129 extern void start_thread(struct pt_regs *regs, unsigned long new_pc, unsigned long new_sp);
 130 
 131 /* Free all resources held by a thread. */
 132 extern void release_thread(struct task_struct *);
 133 
 134 /*
 135  * FPU lazy state save handling.
 136  */
 137 
 138 static __inline__ void disable_fpu(void)
 139 {
 140         unsigned long __dummy;
 141 
 142         /* Set FD flag in SR */
 143         __asm__ __volatile__("stc       sr, %0\n\t"
 144                              "or        %1, %0\n\t"
 145                              "ldc       %0, sr"
 146                              : "=&r" (__dummy)
 147                              : "r" (SR_FD));
 148 }
 149 
 150 static __inline__ void enable_fpu(void)
 151 {
 152         unsigned long __dummy;
 153 
 154         /* Clear out FD flag in SR */
 155         __asm__ __volatile__("stc       sr, %0\n\t"
 156                              "and       %1, %0\n\t"
 157                              "ldc       %0, sr"
 158                              : "=&r" (__dummy)
 159                              : "r" (~SR_FD));
 160 }
 161 
 162 /* Double presision, NANS as NANS, rounding to nearest, no exceptions */
 163 #define FPSCR_INIT  0x00080000
 164 
 165 #define FPSCR_CAUSE_MASK        0x0001f000      /* Cause bits */
 166 #define FPSCR_FLAG_MASK         0x0000007c      /* Flag bits */
 167 
 168 /*
 169  * Return saved PC of a blocked thread.
 170  */
 171 #define thread_saved_pc(tsk)    (tsk->thread.pc)
 172 
 173 void show_trace(struct task_struct *tsk, unsigned long *sp,
 174                 struct pt_regs *regs);
 175 
 176 #ifdef CONFIG_DUMP_CODE
 177 void show_code(struct pt_regs *regs);
 178 #else
 179 static inline void show_code(struct pt_regs *regs)
 180 {
 181 }
 182 #endif
 183 
 184 extern unsigned long get_wchan(struct task_struct *p);
 185 
 186 #define KSTK_EIP(tsk)  (task_pt_regs(tsk)->pc)
 187 #define KSTK_ESP(tsk)  (task_pt_regs(tsk)->regs[15])
 188 
 189 #if defined(CONFIG_CPU_SH2A) || defined(CONFIG_CPU_SH4)
 190 
 191 #define PREFETCH_STRIDE         L1_CACHE_BYTES
 192 #define ARCH_HAS_PREFETCH
 193 #define ARCH_HAS_PREFETCHW
 194 
 195 static inline void prefetch(const void *x)
 196 {
 197         __builtin_prefetch(x, 0, 3);
 198 }
 199 
 200 static inline void prefetchw(const void *x)
 201 {
 202         __builtin_prefetch(x, 1, 3);
 203 }
 204 #endif
 205 
 206 #endif /* __KERNEL__ */
 207 #endif /* __ASM_SH_PROCESSOR_32_H */