src/runtime/mips-linux-os.c

   1 /*
   2  * This is the MIPS Linux incarnation of arch-dependent OS-dependent
   3  * routines. See also "linux-os.c".
   4  */
   5
   6 /*
   7  * This software is part of the SBCL system. See the README file for
   8  * more information.
   9  *
  10  * This software is derived from the CMU CL system, which was
  11  * written at Carnegie Mellon University and released into the
  12  * public domain. The software is in the public domain and is
  13  * provided with absolutely no warranty. See the COPYING and CREDITS
  14  * files for more information.
  15  */
  16
  17 #include <stdio.h>
  18 #include <signal.h>
  19
  20 /* for cacheflush() */
  21 #include <sys/cachectl.h>
  22
  23 #include "sbcl.h"
  24 #include "os.h"
  25 #include "arch.h"
  26
  27 #define CAUSEF_BD (1 << 31)
  28
  29 size_t os_vm_page_size;
  30
  31 int
  32 arch_os_thread_init(struct thread *thread)
  33 {
  34 #ifdef LISP_FEATURE_SB_THREAD
  35 #warning "Check threading support functions"
  36 #endif
  37     return 1;                  /* success */
  38 }
  39
  40 int
  41 arch_os_thread_cleanup(struct thread *thread)
  42 {
  43 #ifdef LISP_FEATURE_SB_THREAD
  44 #warning "Check threading support functions"
  45 #endif
  46     return 1;                  /* success */
  47 }
  48
  49 os_context_register_t *
  50 os_context_register_addr(os_context_t *context, int offset)
  51 {
  52     mcontext_t *mctx = &context->uc_mcontext;
  53     struct sigcontext *ctx = (struct sigcontext *)mctx;
  54     return &ctx->sc_regs[offset];
  55 }
  56
  57 os_context_register_t *
  58 os_context_fpregister_addr(os_context_t *context, int offset)
  59 {
  60     mcontext_t *mctx = &context->uc_mcontext;
  61     struct sigcontext *ctx = (struct sigcontext *)mctx;
  62     return &ctx->sc_fpregs[offset];
  63 }
  64
  65 os_context_register_t *
  66 os_context_pc_addr(os_context_t *context)
  67 {
  68     /* Why do I get all the silly ports? -- CSR, 2002-08-11 */
  69     mcontext_t *mctx = &context->uc_mcontext;
  70     struct sigcontext *ctx = (struct sigcontext *)mctx;
  71     return &ctx->sc_pc;
  72 }
  73
  74 sigset_t *
  75 os_context_sigmask_addr(os_context_t *context)
  76 {
  77     return &(context->uc_sigmask);
  78 }
  79
  80 unsigned int
  81 os_context_fp_control(os_context_t *context)
  82 {
  83     mcontext_t *mctx = &context->uc_mcontext;
  84     struct sigcontext *ctx = (struct sigcontext *)mctx;
  85     return ctx->sc_fpc_csr;
  86 }
  87
  88 void
  89 os_restore_fp_control(os_context_t *context)
  90 {
  91     unsigned int ctl = os_context_fp_control(context);
  92     ctl &= ~(FLOAT_STICKY_BITS_MASK | FLOAT_EXCEPTIONS_BYTE_MASK);
  93     arch_set_fp_control(ctl);
  94 }
  95
  96 unsigned int
  97 os_context_bd_cause(os_context_t *context)
  98 {
  99     /* We need to see if whatever happened, happened because of a
 100        branch delay event */
 101     /* FIXME: However, I'm not convinced that the values that Linux
 102        puts in this slot are actually right; specifically, attempting
 103        to compile sbcl with sbcl-0.7.7.7 lead to an "infinite SIGTRAP
 104        loop" where a (BREAK 16) not in a branch delay slot would have
 105        CAUSEF_BD filled. So, we comment
 106
 107         return (((struct sigcontext *) &(context->uc_mcontext))->sc_cause
 108                 & CAUSEF_BD);
 109
 110        out and return 0 always.  -- CSR, 2002-09-02 */
 111     /* Unfortunately, returning 0 fails for taken branches because
 112        os_context_bd_cause is also used to find out if a branch
 113        emulation is needed.  We work around that by checking if the
 114        current instruction is a jump or a branch.  */
 115     extern boolean arch_insn_with_bdelay_p(unsigned int insn);
 116
 117     os_vm_address_t addr
 118         = (os_vm_address_t)(unsigned int)*os_context_pc_addr(context);
 119     unsigned int insn = *(unsigned int *)addr;
 120
 121     if (arch_insn_with_bdelay_p(insn))
 122         return CAUSEF_BD;
 123
 124     return 0;
 125 }
 126
 127 void
 128 os_flush_icache(os_vm_address_t address, os_vm_size_t length)
 129 {
 130     if (cacheflush(address, length, ICACHE) == -1)
 131         perror("cacheflush");
 132 }