[ARM] Handle HWCAP_VFP in VFP support code

Don't set HWCAP_VFP in the processor support file; not only does it
depend on the processor features, but it also depends on the support
code being present.  Therefore, only set it if the support code
detects that we have a VFP coprocessor attached.

Also, move the VFP handling of the coprocessor access register into
the VFP support code.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 25 insertions, 1 deletions

diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index f08eafbddcc1..e26cc1f59948 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -263,13 +263,24 @@ void VFP9_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs)
         if (exceptions)
                 vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs);
 }
- 
+
 /*
  * 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.
@@ -281,6 +292,12 @@ static int __init vfp_init(void)
         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 {
@@ -291,9 +308,16 @@ static int __init vfp_init(void)
                         (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;
 }