arch/c6x/include/asm/processor.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  *  Port on Texas Instruments TMS320C6x architecture
   4  *
   5  *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
   6  *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
   7  *
   8  *  Updated for 2.6.34: Mark Salter <msalter@redhat.com>
   9  */
  10 #ifndef _ASM_C6X_PROCESSOR_H
  11 #define _ASM_C6X_PROCESSOR_H
  12
  13 #include <asm/ptrace.h>
  14 #include <asm/page.h>
  15 #include <asm/current.h>
  16
  17 /*
  18  * User space process size. This is mostly meaningless for NOMMU
  19  * but some C6X processors may have RAM addresses up to 0xFFFFFFFF.
  20  * Since calls like mmap() can return an address or an error, we
  21  * have to allow room for error returns when code does something
  22  * like:
  23  *
  24  *       addr = do_mmap(...)
  25  *       if ((unsigned long)addr >= TASK_SIZE)
  26  *            ... its an error code, not an address ...
  27  *
  28  * Here, we allow for 4096 error codes which means we really can't
  29  * use the last 4K page on systems with RAM extending all the way
  30  * to the end of the 32-bit address space.
  31  */
  32 #define TASK_SIZE       0xFFFFF000
  33
  34 /*
  35  * This decides where the kernel will search for a free chunk of vm
  36  * space during mmap's. We won't be using it
  37  */
  38 #define TASK_UNMAPPED_BASE      0
  39
  40 struct thread_struct {
  41         unsigned long long b15_14;
  42         unsigned long long a15_14;
  43         unsigned long long b13_12;
  44         unsigned long long a13_12;
  45         unsigned long long b11_10;
  46         unsigned long long a11_10;
  47         unsigned long long ricl_icl;
  48         unsigned long  usp;             /* user stack pointer */
  49         unsigned long  pc;              /* kernel pc */
  50         unsigned long  wchan;
  51 };
  52
  53 #define INIT_THREAD                                     \
  54 {                                                       \
  55         .usp = 0,                                       \
  56         .wchan = 0,                                     \
  57 }
  58
  59 #define INIT_MMAP { \
  60         &init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, \
  61         NULL, NULL }
  62
  63 #define task_pt_regs(task) \
  64         ((struct pt_regs *)(THREAD_START_SP + task_stack_page(task)) - 1)
  65
  66 #define alloc_kernel_stack()    __get_free_page(GFP_KERNEL)
  67 #define free_kernel_stack(page) free_page((page))
  68
  69
  70 /* Forward declaration, a strange C thing */
  71 struct task_struct;
  72
  73 extern void start_thread(struct pt_regs *regs, unsigned int pc,
  74                          unsigned long usp);
  75
  76 /* Free all resources held by a thread. */
  77 static inline void release_thread(struct task_struct *dead_task)
  78 {
  79 }
  80
  81 /*
  82  * saved kernel SP and DP of a blocked thread.
  83  */
  84 #ifdef _BIG_ENDIAN
  85 #define thread_saved_ksp(tsk) \
  86         (*(unsigned long *)&(tsk)->thread.b15_14)
  87 #define thread_saved_dp(tsk) \
  88         (*(((unsigned long *)&(tsk)->thread.b15_14) + 1))
  89 #else
  90 #define thread_saved_ksp(tsk) \
  91         (*(((unsigned long *)&(tsk)->thread.b15_14) + 1))
  92 #define thread_saved_dp(tsk) \
  93         (*(unsigned long *)&(tsk)->thread.b15_14)
  94 #endif
  95
  96 extern unsigned long get_wchan(struct task_struct *p);
  97
  98 #define KSTK_EIP(task)  (task_pt_regs(task)->pc)
  99 #define KSTK_ESP(task)  (task_pt_regs(task)->sp)
 100
 101 #define cpu_relax()             do { } while (0)
 102
 103 extern const struct seq_operations cpuinfo_op;
 104
 105 /* Reset the board */
 106 #define HARD_RESET_NOW()
 107
 108 extern unsigned int c6x_core_freq;
 109
 110
 111 extern void (*c6x_restart)(void);
 112 extern void (*c6x_halt)(void);
 113
 114 #endif /* ASM_C6X_PROCESSOR_H */