LXR linux/arch/tile/include/asm/processor.h

   1/*
   2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
   3 *
   4 *   This program is free software; you can redistribute it and/or
   5 *   modify it under the terms of the GNU General Public License
   6 *   as published by the Free Software Foundation, version 2.
   7 *
   8 *   This program is distributed in the hope that it will be useful, but
   9 *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11 *   NON INFRINGEMENT.  See the GNU General Public License for
  12 *   more details.
  13 */
  14
  15#ifndef _ASM_TILE_PROCESSOR_H
  16#define _ASM_TILE_PROCESSOR_H
  17
  18#ifndef __ASSEMBLY__
  19
  20/*
  21 * NOTE: we don't include <linux/ptrace.h> or <linux/percpu.h> as one
  22 * normally would, due to #include dependencies.
  23 */
  24#include <linux/types.h>
  25#include <asm/ptrace.h>
  26#include <asm/percpu.h>
  27
  28#include <arch/chip.h>
  29#include <arch/spr_def.h>
  30
  31struct task_struct;
  32struct thread_struct;
  33
  34typedef struct {
  35        unsigned long seg;
  36} mm_segment_t;
  37
  38/*
  39 * Default implementation of macro that returns current
  40 * instruction pointer ("program counter").
  41 */
  42void *current_text_addr(void);
  43
  44#if CHIP_HAS_TILE_DMA()
  45/* Capture the state of a suspended DMA. */
  46struct tile_dma_state {
  47        int enabled;
  48        unsigned long src;
  49        unsigned long dest;
  50        unsigned long strides;
  51        unsigned long chunk_size;
  52        unsigned long src_chunk;
  53        unsigned long dest_chunk;
  54        unsigned long byte;
  55        unsigned long status;
  56};
  57
  58/*
  59 * A mask of the DMA status register for selecting only the 'running'
  60 * and 'done' bits.
  61 */
  62#define DMA_STATUS_MASK \
  63  (SPR_DMA_STATUS__RUNNING_MASK | SPR_DMA_STATUS__DONE_MASK)
  64#endif
  65
  66/*
  67 * Track asynchronous TLB events (faults and access violations)
  68 * that occur while we are in kernel mode from DMA or the SN processor.
  69 */
  70struct async_tlb {
  71        short fault_num;         /* original fault number; 0 if none */
  72        char is_fault;           /* was it a fault (vs an access violation) */
  73        char is_write;           /* for fault: was it caused by a write? */
  74        unsigned long address;   /* what address faulted? */
  75};
  76
  77#ifdef CONFIG_HARDWALL
  78struct hardwall_info;
  79#endif
  80
  81struct thread_struct {
  82        /* kernel stack pointer */
  83        unsigned long  ksp;
  84        /* kernel PC */
  85        unsigned long  pc;
  86        /* starting user stack pointer (for page migration) */
  87        unsigned long  usp0;
  88        /* pid of process that created this one */
  89        pid_t creator_pid;
  90#if CHIP_HAS_TILE_DMA()
  91        /* DMA info for suspended threads (byte == 0 means no DMA state) */
  92        struct tile_dma_state tile_dma_state;
  93#endif
  94        /* User EX_CONTEXT registers */
  95        unsigned long ex_context[2];
  96        /* User SYSTEM_SAVE registers */
  97        unsigned long system_save[4];
  98        /* User interrupt mask */
  99        unsigned long long interrupt_mask;
 100        /* User interrupt-control 0 state */
 101        unsigned long intctrl_0;
 102#if CHIP_HAS_PROC_STATUS_SPR()
 103        /* Any other miscellaneous processor state bits */
 104        unsigned long proc_status;
 105#endif
 106#if !CHIP_HAS_FIXED_INTVEC_BASE()
 107        /* Interrupt base for PL0 interrupts */
 108        unsigned long interrupt_vector_base;
 109#endif
 110#if CHIP_HAS_TILE_RTF_HWM()
 111        /* Tile cache retry fifo high-water mark */
 112        unsigned long tile_rtf_hwm;
 113#endif
 114#if CHIP_HAS_DSTREAM_PF()
 115        /* Data stream prefetch control */
 116        unsigned long dstream_pf;
 117#endif
 118#ifdef CONFIG_HARDWALL
 119        /* Is this task tied to an activated hardwall? */
 120        struct hardwall_info *hardwall;
 121        /* Chains this task into the list at hardwall->list. */
 122        struct list_head hardwall_list;
 123#endif
 124#if CHIP_HAS_TILE_DMA()
 125        /* Async DMA TLB fault information */
 126        struct async_tlb dma_async_tlb;
 127#endif
 128#if CHIP_HAS_SN_PROC()
 129        /* Was static network processor when we were switched out? */
 130        int sn_proc_running;
 131        /* Async SNI TLB fault information */
 132        struct async_tlb sn_async_tlb;
 133#endif
 134};
 135
 136#endif /* !__ASSEMBLY__ */
 137
 138/*
 139 * Start with "sp" this many bytes below the top of the kernel stack.
 140 * This preserves the invariant that a called function may write to *sp.
 141 */
 142#define STACK_TOP_DELTA 8
 143
 144/*
 145 * When entering the kernel via a fault, start with the top of the
 146 * pt_regs structure this many bytes below the top of the page.
 147 * This aligns the pt_regs structure optimally for cache-line access.
 148 */
 149#ifdef __tilegx__
 150#define KSTK_PTREGS_GAP  48
 151#else
 152#define KSTK_PTREGS_GAP  56
 153#endif
 154
 155#ifndef __ASSEMBLY__
 156
 157#ifdef __tilegx__
 158#define TASK_SIZE_MAX           (MEM_LOW_END + 1)
 159#else
 160#define TASK_SIZE_MAX           PAGE_OFFSET
 161#endif
 162
 163/* TASK_SIZE and related variables are always checked in "current" context. */
 164#ifdef CONFIG_COMPAT
 165#define COMPAT_TASK_SIZE        (1UL << 31)
 166#define TASK_SIZE               ((current_thread_info()->status & TS_COMPAT) ?\
 167                                 COMPAT_TASK_SIZE : TASK_SIZE_MAX)
 168#else
 169#define TASK_SIZE               TASK_SIZE_MAX
 170#endif
 171
 172/* We provide a minimal "vdso" a la x86; just the sigreturn code for now. */
 173#define VDSO_BASE               (TASK_SIZE - PAGE_SIZE)
 174
 175#define STACK_TOP               VDSO_BASE
 176
 177/* STACK_TOP_MAX is used temporarily in execve and should not check COMPAT. */
 178#define STACK_TOP_MAX           TASK_SIZE_MAX
 179
 180/*
 181 * This decides where the kernel will search for a free chunk of vm
 182 * space during mmap's, if it is using bottom-up mapping.
 183 */
 184#define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 3))
 185
 186#define HAVE_ARCH_PICK_MMAP_LAYOUT
 187
 188#define INIT_THREAD {                                                   \
 189        .ksp = (unsigned long)init_stack + THREAD_SIZE - STACK_TOP_DELTA, \
 190        .interrupt_mask = -1ULL                                         \
 191}
 192
 193/* Kernel stack top for the task that first boots on this cpu. */
 194DECLARE_PER_CPU(unsigned long, boot_sp);
 195
 196/* PC to boot from on this cpu. */
 197DECLARE_PER_CPU(unsigned long, boot_pc);
 198
 199/* Do necessary setup to start up a newly executed thread. */
 200static inline void start_thread(struct pt_regs *regs,
 201                                unsigned long pc, unsigned long usp)
 202{
 203        regs->pc = pc;
 204        regs->sp = usp;
 205}
 206
 207/* Free all resources held by a thread. */
 208static inline void release_thread(struct task_struct *dead_task)
 209{
 210        /* Nothing for now */
 211}
 212
 213/* Prepare to copy thread state - unlazy all lazy status. */
 214#define prepare_to_copy(tsk)    do { } while (0)
 215
 216extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
 217
 218extern int do_work_pending(struct pt_regs *regs, u32 flags);
 219
 220
 221/*
 222 * Return saved (kernel) PC of a blocked thread.
 223 * Only used in a printk() in kernel/sched.c, so don't work too hard.
 224 */
 225#define thread_saved_pc(t)   ((t)->thread.pc)
 226
 227unsigned long get_wchan(struct task_struct *p);
 228
 229/* Return initial ksp value for given task. */
 230#define task_ksp0(task) ((unsigned long)(task)->stack + THREAD_SIZE)
 231
 232/* Return some info about the user process TASK. */
 233#define KSTK_TOP(task)  (task_ksp0(task) - STACK_TOP_DELTA)
 234#define task_pt_regs(task) \
 235  ((struct pt_regs *)(task_ksp0(task) - KSTK_PTREGS_GAP) - 1)
 236#define task_sp(task)   (task_pt_regs(task)->sp)
 237#define task_pc(task)   (task_pt_regs(task)->pc)
 238/* Aliases for pc and sp (used in fs/proc/array.c) */
 239#define KSTK_EIP(task)  task_pc(task)
 240#define KSTK_ESP(task)  task_sp(task)
 241
 242/* Standard format for printing registers and other word-size data. */
 243#ifdef __tilegx__
 244# define REGFMT "0x%016lx"
 245#else
 246# define REGFMT "0x%08lx"
 247#endif
 248
 249/*
 250 * Do some slow action (e.g. read a slow SPR).
 251 * Note that this must also have compiler-barrier semantics since
 252 * it may be used in a busy loop reading memory.
 253 */
 254static inline void cpu_relax(void)
 255{
 256        __insn_mfspr(SPR_PASS);
 257        barrier();
 258}
 259
 260/* Info on this processor (see fs/proc/cpuinfo.c) */
 261struct seq_operations;
 262extern const struct seq_operations cpuinfo_op;
 263
 264/* Provide information about the chip model. */
 265extern char chip_model[64];
 266
 267/* Data on which physical memory controller corresponds to which NUMA node. */
 268extern int node_controller[];
 269
 270#if CHIP_HAS_CBOX_HOME_MAP()
 271/* Does the heap allocator return hash-for-home pages by default? */
 272extern int hash_default;
 273
 274/* Should kernel stack pages be hash-for-home? */
 275extern int kstack_hash;
 276
 277/* Does MAP_ANONYMOUS return hash-for-home pages by default? */
 278#define uheap_hash hash_default
 279
 280#else
 281#define hash_default 0
 282#define kstack_hash 0
 283#define uheap_hash 0
 284#endif
 285
 286/* Are we using huge pages in the TLB for kernel data? */
 287extern int kdata_huge;
 288
 289/* Support standard Linux prefetching. */
 290#define ARCH_HAS_PREFETCH
 291#define prefetch(x) __builtin_prefetch(x)
 292#define PREFETCH_STRIDE CHIP_L2_LINE_SIZE()
 293
 294/* Bring a value into the L1D, faulting the TLB if necessary. */
 295#ifdef __tilegx__
 296#define prefetch_L1(x) __insn_prefetch_l1_fault((void *)(x))
 297#else
 298#define prefetch_L1(x) __insn_prefetch_L1((void *)(x))
 299#endif
 300
 301#else /* __ASSEMBLY__ */
 302
 303/* Do some slow action (e.g. read a slow SPR). */
 304#define CPU_RELAX       mfspr zero, SPR_PASS
 305
 306#endif /* !__ASSEMBLY__ */
 307
 308/* Assembly code assumes that the PL is in the low bits. */
 309#if SPR_EX_CONTEXT_1_1__PL_SHIFT != 0
 310# error Fix assembly assumptions about PL
 311#endif
 312
 313/* We sometimes use these macros for EX_CONTEXT_0_1 as well. */
 314#if SPR_EX_CONTEXT_1_1__PL_SHIFT != SPR_EX_CONTEXT_0_1__PL_SHIFT || \
 315    SPR_EX_CONTEXT_1_1__PL_RMASK != SPR_EX_CONTEXT_0_1__PL_RMASK || \
 316    SPR_EX_CONTEXT_1_1__ICS_SHIFT != SPR_EX_CONTEXT_0_1__ICS_SHIFT || \
 317    SPR_EX_CONTEXT_1_1__ICS_RMASK != SPR_EX_CONTEXT_0_1__ICS_RMASK
 318# error Fix assumptions that EX1 macros work for both PL0 and PL1
 319#endif
 320
 321/* Allow pulling apart and recombining the PL and ICS bits in EX_CONTEXT. */
 322#define EX1_PL(ex1) \
 323  (((ex1) >> SPR_EX_CONTEXT_1_1__PL_SHIFT) & SPR_EX_CONTEXT_1_1__PL_RMASK)
 324#define EX1_ICS(ex1) \
 325  (((ex1) >> SPR_EX_CONTEXT_1_1__ICS_SHIFT) & SPR_EX_CONTEXT_1_1__ICS_RMASK)
 326#define PL_ICS_EX1(pl, ics) \
 327  (((pl) << SPR_EX_CONTEXT_1_1__PL_SHIFT) | \
 328   ((ics) << SPR_EX_CONTEXT_1_1__ICS_SHIFT))
 329
 330/*
 331 * Provide symbolic constants for PLs.
 332 * Note that assembly code assumes that USER_PL is zero.
 333 */
 334#define USER_PL 0
 335#if CONFIG_KERNEL_PL == 2
 336#define GUEST_PL 1
 337#endif
 338#define KERNEL_PL CONFIG_KERNEL_PL
 339
 340/* SYSTEM_SAVE_K_0 holds the current cpu number ORed with ksp0. */
 341#define CPU_LOG_MASK_VALUE 12
 342#define CPU_MASK_VALUE ((1 << CPU_LOG_MASK_VALUE) - 1)
 343#if CONFIG_NR_CPUS > CPU_MASK_VALUE
 344# error Too many cpus!
 345#endif
 346#define raw_smp_processor_id() \
 347        ((int)__insn_mfspr(SPR_SYSTEM_SAVE_K_0) & CPU_MASK_VALUE)
 348#define get_current_ksp0() \
 349        (__insn_mfspr(SPR_SYSTEM_SAVE_K_0) & ~CPU_MASK_VALUE)
 350#define next_current_ksp0(task) ({ \
 351        unsigned long __ksp0 = task_ksp0(task); \
 352        int __cpu = raw_smp_processor_id(); \
 353        BUG_ON(__ksp0 & CPU_MASK_VALUE); \
 354        __ksp0 | __cpu; \
 355})
 356
 357#endif /* _ASM_TILE_PROCESSOR_H */
 358