コード例 #1
0
/*
 * VFP support code initialisation.
 */
static int __init vfp_init(void)
{
	unsigned int vfpsid;
	unsigned int cpu_arch = cpu_architecture();
	u32 access = 0;

	if (cpu_arch >= CPU_ARCH_ARMv6) {
		access = get_copro_access();

		/*
		 * Enable full access to VFP (cp10 and cp11)
		 */
		set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11));
	}

	/*
	 * First check that there is a VFP that we can use.
	 * The handler is already setup to just log calls, so
	 * we just need to read the VFPSID register.
	 */
	vfp_vector = vfp_testing_entry;
	barrier();
	vfpsid = fmrx(FPSID);
	barrier();
	vfp_vector = vfp_null_entry;

	printk(KERN_INFO "VFP support v0.3: ");
	if (VFP_arch) {
		printk("not present\n");

		/*
		 * Restore the copro access register.
		 */
		if (cpu_arch >= CPU_ARCH_ARMv6)
			set_copro_access(access);
	} else if (vfpsid & FPSID_NODOUBLE) {
		printk("no double precision support\n");
	} else {
		smp_call_function(vfp_enable, NULL, 1, 1);

		VFP_arch = (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT;  /* Extract the architecture version */
		printk("implementor %02x architecture %d part %02x variant %x rev %x\n",
			(vfpsid & FPSID_IMPLEMENTER_MASK) >> FPSID_IMPLEMENTER_BIT,
			(vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT,
			(vfpsid & FPSID_PART_MASK) >> FPSID_PART_BIT,
			(vfpsid & FPSID_VARIANT_MASK) >> FPSID_VARIANT_BIT,
			(vfpsid & FPSID_REV_MASK) >> FPSID_REV_BIT);

		vfp_vector = vfp_support_entry;

		thread_register_notifier(&vfp_notifier_block);

		/*
		 * We detected VFP, and the support code is
		 * in place; report VFP support to userspace.
		 */
		elf_hwcap |= HWCAP_VFP;
	}
	return 0;
}
コード例 #2
0
static void vfp_enable(void *unused)
{
	u32 access = get_copro_access();

	/*
	 * Enable full access to VFP (cp10 and cp11)
	 */
	set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11));
}
コード例 #3
0
static void vfp_enable(void *unused)
{
	u32 access;

	BUG_ON(preemptible());
	access = get_copro_access();

	set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11));
}