2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (C) 1994 Waldorf GMBH
7 * Copyright (C) 1995, 1996, 1997, 1998, 1999, 2001, 2002, 2003 Ralf Baechle
8 * Copyright (C) 1996 Paul M. Antoine
9 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
11 #ifndef _ASM_PROCESSOR_H
12 #define _ASM_PROCESSOR_H
14 #include <linux/config.h>
15 #include <linux/threads.h>
17 #include <asm/cachectl.h>
19 #include <asm/cpu-info.h>
20 #include <asm/mipsregs.h>
21 #include <asm/prefetch.h>
22 #include <asm/system.h>
25 * Return current * instruction pointer ("program counter").
27 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
30 * System setup and hardware flags..
32 extern void (*cpu_wait)(void);
34 extern unsigned int vced_count, vcei_count;
38 * User space process size: 2GB. This is hardcoded into a few places,
39 * so don't change it unless you know what you are doing.
41 #define TASK_SIZE 0x7fff8000UL
44 * This decides where the kernel will search for a free chunk of vm
45 * space during mmap's.
47 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 3))
52 * User space process size: 1TB. This is hardcoded into a few places,
53 * so don't change it unless you know what you are doing. TASK_SIZE
54 * is limited to 1TB by the R4000 architecture; R10000 and better can
55 * support 16TB; the architectural reserve for future expansion is
58 #define TASK_SIZE32 0x7fff8000UL
59 #define TASK_SIZE 0x10000000000UL
62 * This decides where the kernel will search for a free chunk of vm
63 * space during mmap's.
65 #define TASK_UNMAPPED_BASE ((current->thread.mflags & MF_32BIT_ADDR) ? \
66 PAGE_ALIGN(TASK_SIZE32 / 3) : PAGE_ALIGN(TASK_SIZE / 3))
69 #define NUM_FPU_REGS 32
71 typedef __u64 fpureg_t;
73 struct mips_fpu_hard_struct {
74 fpureg_t fpr[NUM_FPU_REGS];
79 * It would be nice to add some more fields for emulator statistics, but there
80 * are a number of fixed offsets in offset.h and elsewhere that would have to
81 * be recalculated by hand. So the additional information will be private to
82 * the FPU emulator for now. See asm-mips/fpu_emulator.h.
85 struct mips_fpu_soft_struct {
86 fpureg_t fpr[NUM_FPU_REGS];
90 union mips_fpu_union {
91 struct mips_fpu_hard_struct hard;
92 struct mips_fpu_soft_struct soft;
103 #define ARCH_MIN_TASKALIGN 8
106 * If you change thread_struct remember to change the #defines below too!
108 struct thread_struct {
109 /* Saved main processor registers. */
111 unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23;
112 unsigned long reg29, reg30, reg31;
114 /* Saved cp0 stuff. */
115 unsigned long cp0_status;
117 /* Saved fpu/fpu emulator stuff. */
118 union mips_fpu_union fpu;
120 /* Other stuff associated with the thread. */
121 unsigned long cp0_badvaddr; /* Last user fault */
122 unsigned long cp0_baduaddr; /* Last kernel fault accessing USEG */
123 unsigned long error_code;
124 unsigned long trap_no;
125 #define MF_FIXADE 1 /* Fix address errors in software */
126 #define MF_LOGADE 2 /* Log address errors to syslog */
127 #define MF_32BIT_REGS 4 /* also implies 16/32 fprs */
128 #define MF_32BIT_ADDR 8 /* 32-bit address space (o32/n32) */
129 unsigned long mflags;
130 unsigned long irix_trampoline; /* Wheee... */
131 unsigned long irix_oldctx;
134 #define MF_ABI_MASK (MF_32BIT_REGS | MF_32BIT_ADDR)
135 #define MF_O32 (MF_32BIT_REGS | MF_32BIT_ADDR)
136 #define MF_N32 MF_32BIT_ADDR
139 #define INIT_THREAD { \
141 * saved main processor registers \
143 0, 0, 0, 0, 0, 0, 0, 0, \
150 * saved fpu/fpu emulator stuff \
154 * Other stuff associated with the process \
158 * For now the default is to fix address errors \
165 /* Free all resources held by a thread. */
166 #define release_thread(thread) do { } while(0)
168 /* Prepare to copy thread state - unlazy all lazy status */
169 #define prepare_to_copy(tsk) do { } while (0)
171 extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
173 extern unsigned long thread_saved_pc(struct task_struct *tsk);
176 * Do necessary setup to start up a newly executed thread.
178 extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp);
180 unsigned long get_wchan(struct task_struct *p);
182 #define __PT_REG(reg) ((long)&((struct pt_regs *)0)->reg - sizeof(struct pt_regs))
183 #define __KSTK_TOS(tsk) ((unsigned long)(tsk->thread_info) + THREAD_SIZE - 32)
184 #define KSTK_EIP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(cp0_epc)))
185 #define KSTK_ESP(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(regs[29])))
186 #define KSTK_STATUS(tsk) (*(unsigned long *)(__KSTK_TOS(tsk) + __PT_REG(cp0_status)))
188 #define cpu_relax() barrier()
191 * Return_address is a replacement for __builtin_return_address(count)
192 * which on certain architectures cannot reasonably be implemented in GCC
193 * (MIPS, Alpha) or is unuseable with -fomit-frame-pointer (i386).
194 * Note that __builtin_return_address(x>=1) is forbidden because GCC
195 * aborts compilation on some CPUs. It's simply not possible to unwind
196 * some CPU's stackframes.
198 * __builtin_return_address works only for non-leaf functions. We avoid the
199 * overhead of a function call by forcing the compiler to save the return
200 * address register on the stack.
202 #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);})
204 #ifdef CONFIG_CPU_HAS_PREFETCH
206 #define ARCH_HAS_PREFETCH
208 extern inline void prefetch(const void *addr)
210 __asm__ __volatile__(
215 : "i" (Pref_Load), "r" (addr));
220 #endif /* _ASM_PROCESSOR_H */