static void init_amd_k6(struct cpuinfo_x86 *c)
{
	u32 l, h;
	int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);

	if (c->x86_model < 6) {
		/* Based on AMD doc 20734R - June 2000 */
		if (c->x86_model == 0) {
			clear_cpu_cap(c, X86_FEATURE_APIC);
			set_cpu_cap(c, X86_FEATURE_PGE);
		}
		return;
	}

	if (c->x86_model == 6 && c->x86_mask == 1) {
		const int K6_BUG_LOOP = 1000000;
		int n;
		void (*f_vide)(void);
		unsigned long d, d2;

		printk(KERN_INFO "AMD K6 stepping B detected - ");

		/*
		 * It looks like AMD fixed the 2.6.2 bug and improved indirect
		 * calls at the same time.
		 */

		n = K6_BUG_LOOP;
		f_vide = vide;
		rdtscl(d);
		while (n--)
			f_vide();
		rdtscl(d2);
		d = d2-d;

		if (d > 20*K6_BUG_LOOP)
			printk(KERN_CONT
				"system stability may be impaired when more than 32 MB are used.\n");
		else
			printk(KERN_CONT "probably OK (after B9730xxxx).\n");
	}

	/* K6 with old style WHCR */
	if (c->x86_model < 8 ||
	   (c->x86_model == 8 && c->x86_mask < 8)) {
		/* We can only write allocate on the low 508Mb */
		if (mbytes > 508)
			mbytes = 508;

		rdmsr(MSR_K6_WHCR, l, h);
		if ((l&0x0000FFFF) == 0) {
			unsigned long flags;
			l = (1<<0)|((mbytes/4)<<1);
			local_irq_save(flags);
			wbinvd();
			wrmsr(MSR_K6_WHCR, l, h);
			local_irq_restore(flags);
			printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
				mbytes);
		}
		return;
	}

	if ((c->x86_model == 8 && c->x86_mask > 7) ||
	     c->x86_model == 9 || c->x86_model == 13) {
		/* The more serious chips .. */

		if (mbytes > 4092)
			mbytes = 4092;

		rdmsr(MSR_K6_WHCR, l, h);
		if ((l&0xFFFF0000) == 0) {
			unsigned long flags;
			l = ((mbytes>>2)<<22)|(1<<16);
			local_irq_save(flags);
			wbinvd();
			wrmsr(MSR_K6_WHCR, l, h);
			local_irq_restore(flags);
			printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
				mbytes);
		}

		return;
	}

	if (c->x86_model == 10) {
		/* AMD Geode LX is model 10 */
		/* placeholder for any needed mods */
		return;
	}
}
Unknown