/* $Id: processor.h,v 1.3 1999/09/27 20:56:47 ralf Exp $ * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 1994 Waldorf GMBH * Copyright (C) 1995, 1996, 1997, 1998, 1999 Ralf Baechle * Modified further for R[236]000 compatibility by Paul M. Antoine * Copyright (C) 1999 Silicon Graphics, Inc. */ #ifndef _ASM_PROCESSOR_H #define _ASM_PROCESSOR_H /* * Default implementation of macro that returns current * instruction pointer ("program counter"). */ #define current_text_addr() ({ __label__ _l; _l: &&_l;}) #if !defined (_LANGUAGE_ASSEMBLY) #include #include #include #include struct mips_cpuinfo { unsigned long udelay_val; unsigned long *pgd_quick; unsigned long *pte_quick; unsigned long pgtable_cache_sz; }; /* * System setup and hardware flags.. * XXX: Should go into mips_cpuinfo. */ extern char wait_available; /* only available on R4[26]00 */ extern char cyclecounter_available; /* only available from R4000 upwards. */ extern char dedicated_iv_available; /* some embedded MIPS like Nevada */ extern char vce_available; /* Supports VCED / VCEI exceptions */ extern struct mips_cpuinfo boot_cpu_data; extern unsigned int vced_count, vcei_count; #ifdef __SMP__ extern struct mips_cpuinfo cpu_data[]; #define current_cpu_data cpu_data[smp_processor_id()] #else #define cpu_data &boot_cpu_data #define current_cpu_data boot_cpu_data #endif /* * Bus types (default is ISA, but people can check others with these..) * MCA_bus hardcoded to 0 for now. * * This needs to be extended since MIPS systems are being delivered with * numerous different types of bus systems. */ extern int EISA_bus; #define MCA_bus 0 #define MCA_bus__is_a_macro /* for versions in ksyms.c */ /* * MIPS has no problems with write protection */ #define wp_works_ok 1 #define wp_works_ok__is_a_macro /* for versions in ksyms.c */ /* Lazy FPU handling on uni-processor */ extern struct task_struct *last_task_used_math; /* * User space process size: 2GB. This is hardcoded into a few places, * so don't change it unless you know what you are doing. TASK_SIZE * for a 64 bit kernel expandable to 8192EB, of which the current MIPS * implementations will "only" be able to use 1TB ... */ #define TASK_SIZE (0x80000000UL) /* This decides where the kernel will search for a free chunk of vm * space during mmap's. */ #define TASK_UNMAPPED_BASE (TASK_SIZE / 3) /* * Size of io_bitmap in longwords: 32 is ports 0-0x3ff. */ #define IO_BITMAP_SIZE 32 #define NUM_FPU_REGS 32 struct mips_fpu_hard_struct { unsigned int fp_regs[NUM_FPU_REGS]; unsigned int control; } __attribute__((aligned(8))); /* * FIXME: no fpu emulator yet (but who cares anyway?) */ struct mips_fpu_soft_struct { long dummy; }; union mips_fpu_union { struct mips_fpu_hard_struct hard; struct mips_fpu_soft_struct soft; }; #define INIT_FPU { \ {{0,},} \ } typedef struct { unsigned long seg; } mm_segment_t; /* * If you change thread_struct remember to change the #defines below too! */ struct thread_struct { /* Saved main processor registers. */ unsigned long reg16; unsigned long reg17, reg18, reg19, reg20, reg21, reg22, reg23; unsigned long reg29, reg30, reg31; /* Saved cp0 stuff. */ unsigned long cp0_status; /* Saved fpu/fpu emulator stuff. */ union mips_fpu_union fpu; /* Other stuff associated with the thread. */ unsigned long cp0_badvaddr; /* Last user fault */ unsigned long cp0_baduaddr; /* Last kernel fault accessing USEG */ unsigned long error_code; unsigned long trap_no; unsigned long pg_dir; /* used in tlb refill */ #define MF_FIXADE 1 /* Fix address errors in software */ #define MF_LOGADE 2 /* Log address errors to syslog */ unsigned long mflags; mm_segment_t current_ds; unsigned long irix_trampoline; /* Wheee... */ unsigned long irix_oldctx; }; #endif /* !defined (_LANGUAGE_ASSEMBLY) */ #define INIT_MMAP { &init_mm, KSEG0, KSEG1, NULL, PAGE_SHARED, \ VM_READ | VM_WRITE | VM_EXEC, 1, NULL, NULL } #define INIT_TSS { \ /* \ * saved main processor registers \ */ \ 0, 0, 0, 0, 0, 0, 0, 0, \ 0, 0, 0, \ /* \ * saved cp0 stuff \ */ \ 0, \ /* \ * saved fpu/fpu emulator stuff \ */ \ INIT_FPU, \ /* \ * Other stuff associated with the process \ */ \ 0, 0, 0, 0, (unsigned long) swapper_pg_dir, \ /* \ * For now the default is to fix address errors \ */ \ MF_FIXADE, { 0 }, 0, 0 \ } #ifdef __KERNEL__ #define KERNEL_STACK_SIZE 8192 #if !defined (_LANGUAGE_ASSEMBLY) /* Free all resources held by a thread. */ extern void release_thread(struct task_struct *); extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags); /* Copy and release all segment info associated with a VM */ #define copy_segments(nr, p, mm) do { } while(0) #define release_segments(mm) do { } while(0) #define forget_segments() do { } while (0) /* * Return saved PC of a blocked thread. */ extern inline unsigned long thread_saved_pc(struct thread_struct *t) { extern void ret_from_sys_call(void); /* New born processes are a special case */ if (t->reg31 == (unsigned long) ret_from_sys_call) return t->reg31; return ((unsigned long*)t->reg29)[17]; } struct pt_regs; extern int (*user_mode)(struct pt_regs *); /* * Do necessary setup to start up a newly executed thread. */ #define start_thread(regs, new_pc, new_sp) do { \ /* New thread looses kernel privileges. */ \ regs->cp0_status = (regs->cp0_status & ~(ST0_CU0|ST0_KSU)) | KSU_USER;\ regs->cp0_epc = new_pc; \ regs->regs[29] = new_sp; \ current->tss.current_ds = USER_DS; \ } while (0) /* Allocation and freeing of basic task resources. */ /* * NOTE! The task struct and the stack go together */ #define alloc_task_struct() \ ((struct task_struct *) __get_free_pages(GFP_KERNEL,1)) #define free_task_struct(p) free_pages((unsigned long)(p),1) #define init_task (init_task_union.task) #define init_stack (init_task_union.stack) #endif /* !defined (_LANGUAGE_ASSEMBLY) */ #endif /* __KERNEL__ */ /* * Return_address is a replacement for __builtin_return_address(count) * which on certain architectures cannot reasonably be implemented in GCC * (MIPS, Alpha) or is unuseable with -fomit-frame-pointer (i386). * Note that __builtin_return_address(x>=1) is forbidden because GCC * aborts compilation on some CPUs. It's simply not possible to unwind * some CPU's stackframes. * * In gcc 2.8 and newer __builtin_return_address works only for non-leaf * functions. We avoid the overhead of a function call by forcing the * compiler to save the return address register on the stack. */ #define return_address() ({__asm__ __volatile__("":::"$31");__builtin_return_address(0);}) #endif /* _ASM_PROCESSOR_H */