cpu.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

/* cpu.c: Dinky routines to look for the kind of Sparc cpu
 *        we are on.
 *
 * Copyright (C) 1996 David S. Miller ([e-mail])
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <asm/asi.h>
#include <asm/system.h>
#include <asm/fpumacro.h>

struct cpu_iu_info {
  short manuf;
  short impl;
  char* cpu_name;   /* should be enough I hope... */
};

struct cpu_fp_info {
  short manuf;
  short impl;
  char fpu_vers;
  char* fp_name;
};

/* In order to get the fpu type correct, you need to take the IDPROM's
 * machine type value into consideration too.  I will fix this.
 */
struct cpu_fp_info linux_sparc_fpu[] = {
  { 0x17, 0x10, 0, "UltraSparc I integrated FPU"},
  { 0x22, 0x10, 0, "UltraSparc I integrated FPU"},
  { 0x17, 0x11, 0, "UltraSparc II integrated FPU"},
  { 0x17, 0x12, 0, "UltraSparc IIi integrated FPU"},
  { 0x17, 0x13, 0, "UltraSparc IIe integrated FPU"},
  { 0x3e, 0x14, 0, "UltraSparc III integrated FPU"},
  { 0x3e, 0x15, 0, "UltraSparc III+ integrated FPU"},
};

#define NSPARCFPU  (sizeof(linux_sparc_fpu)/sizeof(struct cpu_fp_info))

struct cpu_iu_info linux_sparc_chips[] = {
  { 0x17, 0x10, "TI UltraSparc I   (SpitFire)"},
  { 0x22, 0x10, "TI UltraSparc I   (SpitFire)"},
  { 0x17, 0x11, "TI UltraSparc II  (BlackBird)"},
  { 0x17, 0x12, "TI UltraSparc IIi"},
  { 0x17, 0x13, "TI UltraSparc IIe"},
  { 0x3e, 0x14, "TI UltraSparc III (Cheetah)"},
  { 0x3e, 0x15, "TI UltraSparc III+ (Cheetah+)"},
};

#define NSPARCCHIPS  (sizeof(linux_sparc_chips)/sizeof(struct cpu_iu_info))

#ifdef CONFIG_SMP
char *sparc_cpu_type[64] = { "cpu-oops", "cpu-oops1", "cpu-oops2", "cpu-oops3" };
char *sparc_fpu_type[64] = { "fpu-oops", "fpu-oops1", "fpu-oops2", "fpu-oops3" };
#else
char *sparc_cpu_type[64] = { "cpu-oops", };
char *sparc_fpu_type[64] = { "fpu-oops", };
#endif

unsigned int fsr_storage;

void __init cpu_probe(void)
{
	unsigned long ver, fpu_vers, manuf, impl, fprs;
	int i, cpuid;
	
	cpuid = hard_smp_processor_id();

	fprs = fprs_read();
	fprs_write(FPRS_FEF);
	__asm__ __volatile__ ("rdpr %%ver, %0; stx %%fsr, [%1]"
			      : "=&r" (ver)
			      : "r" (&fpu_vers));
	fprs_write(fprs);
	
	manuf = ((ver >> 48) & 0xffff);
	impl = ((ver >> 32) & 0xffff);

	fpu_vers = ((fpu_vers >> 17) & 0x7);

 retry:
	for (i = 0; i < NSPARCCHIPS; i++) {
		if (linux_sparc_chips[i].manuf == manuf) {
			if (linux_sparc_chips[i].impl == impl) {
				sparc_cpu_type[cpuid]
					= linux_sparc_chips[i].cpu_name;
				break;
			}
		}
	}

	if (i == NSPARCCHIPS) {
		/* Maybe it is a cheetah+ derivative, report it as cheetah+
		 * in that case until we learn the real names.
		 */
		if (manuf == 0x3e &&
		    impl > 0x15) {
			impl = 0x15;
			goto retry;
		} else {
			printk("DEBUG: manuf[%lx] impl[%lx]\n",
			       manuf, impl);
		}
		sparc_cpu_type[cpuid] = "Unknown CPU";
	}

	for (i = 0; i < NSPARCFPU; i++) {
		if (linux_sparc_fpu[i].manuf == manuf &&
		    linux_sparc_fpu[i].impl == impl) {
			if (linux_sparc_fpu[i].fpu_vers == fpu_vers) {
				sparc_fpu_type[cpuid]
					= linux_sparc_fpu[i].fp_name;
				break;
			}
		}
	}

	if (i == NSPARCFPU) {
		printk("DEBUG: manuf[%lx] impl[%lx] fsr.vers[%lx]\n",
		       manuf, impl, fpu_vers);
		sparc_fpu_type[cpuid] = "Unknown FPU";
	}
}