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go/src/pkg/runtime/os_linux_arm.c
Russ Cox e9d62a6d81 runtime: refactor os-specific code
thread_GOOS.c becomes os_GOOS.c.

signal_GOOS_GOARCH.c becomes os_GOOS_GOARCH.c,
but with non-GOARCH-specific code moved into os_GOOS.c.

The actual arch-specific signal handler moves into signal_GOARCH.c
to avoid per-GOOS duplication.

New files signal_GOOS_GOARCH.h provide macros for
accessing fields of the very system-specific signal info structs.

Lots moving, but nothing changing.
This is a preliminarly cleanup so I can work on the signal
handling code to fix some open issues without having to
make each change 13 times.

Tested on Linux and OS X, 386 and amd64.
Will fix Plan 9, Windows, and ARM after the fact if necessary.
(Plan 9 and Windows should be fine; ARM will probably have some typos.)

Net effect: -1081 lines of code.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/7565048
2013-03-14 11:35:13 -07:00

83 lines
2.4 KiB
C

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "runtime.h"
#include "defs_GOOS_GOARCH.h"
#include "os_GOOS.h"
#define AT_NULL 0
#define AT_PLATFORM 15 // introduced in at least 2.6.11
#define AT_HWCAP 16 // introduced in at least 2.6.11
#define AT_RANDOM 25 // introduced in 2.6.29
#define HWCAP_VFP (1 << 6) // introduced in at least 2.6.11
#define HWCAP_VFPv3 (1 << 13) // introduced in 2.6.30
static uint32 runtime·randomNumber;
uint8 runtime·armArch = 6; // we default to ARMv6
uint32 runtime·hwcap; // set by setup_auxv
uint8 runtime·goarm; // set by 5l
void
runtime·checkgoarm(void)
{
if(runtime·goarm > 5 && !(runtime·hwcap & HWCAP_VFP)) {
runtime·printf("runtime: this CPU has no floating point hardware, so it cannot run\n");
runtime·printf("this GOARM=%d binary. Recompile using GOARM=5.\n", runtime·goarm);
runtime·exit(1);
}
if(runtime·goarm > 6 && !(runtime·hwcap & HWCAP_VFPv3)) {
runtime·printf("runtime: this CPU has no VFPv3 floating point hardware, so it cannot run\n");
runtime·printf("this GOARM=%d binary. Recompile using GOARM=6.\n", runtime·goarm);
runtime·exit(1);
}
}
#pragma textflag 7
void
runtime·setup_auxv(int32 argc, void *argv_list)
{
byte **argv;
byte **envp;
byte *rnd;
uint32 *auxv;
uint32 t;
argv = &argv_list;
// skip envp to get to ELF auxiliary vector.
for(envp = &argv[argc+1]; *envp != nil; envp++)
;
envp++;
for(auxv=(uint32*)envp; auxv[0] != AT_NULL; auxv += 2) {
switch(auxv[0]) {
case AT_RANDOM: // kernel provided 16-byte worth of random data
if(auxv[1]) {
rnd = (byte*)auxv[1];
runtime·randomNumber = rnd[4] | rnd[5]<<8 | rnd[6]<<16 | rnd[7]<<24;
}
break;
case AT_PLATFORM: // v5l, v6l, v7l
if(auxv[1]) {
t = *(uint8*)(auxv[1]+1);
if(t >= '5' && t <= '7')
runtime·armArch = t - '0';
}
break;
case AT_HWCAP: // CPU capability bit flags
runtime·hwcap = auxv[1];
break;
}
}
}
#pragma textflag 7
int64
runtime·cputicks(void)
{
// Currently cputicks() is used in blocking profiler and to seed runtime·fastrand1().
// runtime·nanotime() is a poor approximation of CPU ticks that is enough for the profiler.
// runtime·randomNumber provides better seeding of fastrand1.
return runtime·nanotime() + runtime·randomNumber;
}