[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>
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 238dd9b..cf2bd42 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -354,9 +354,6 @@
#ifndef CONFIG_ARM_THUMB
elf_hwcap &= ~HWCAP_THUMB;
#endif
-#ifndef CONFIG_VFP
- elf_hwcap &= ~HWCAP_VFP;
-#endif
cpu_proc_init();
}
diff --git a/arch/arm/mm/proc-arm926.S b/arch/arm/mm/proc-arm926.S
index 8628ed2..080efac 100644
--- a/arch/arm/mm/proc-arm926.S
+++ b/arch/arm/mm/proc-arm926.S
@@ -480,7 +480,7 @@
b __arm926_setup
.long cpu_arch_name
.long cpu_elf_name
- .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_VFP|HWCAP_EDSP|HWCAP_JAVA
+ .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP|HWCAP_JAVA
.long cpu_arm926_name
.long arm926_processor_functions
.long v4wbi_tlb_fns
diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S
index b440c8a..c40baf8 100644
--- a/arch/arm/mm/proc-v6.S
+++ b/arch/arm/mm/proc-v6.S
@@ -207,11 +207,6 @@
#endif
mcr p15, 0, r4, c2, c0, 1 @ load TTB1
#endif /* CONFIG_MMU */
-#ifdef CONFIG_VFP
- mrc p15, 0, r0, c1, c0, 2
- orr r0, r0, #(0xf << 20)
- mcr p15, 0, r0, c1, c0, 2 @ Enable full access to VFP
-#endif
adr r5, v6_crval
ldmia r5, {r5, r6}
mrc p15, 0, r0, c1, c0, 0 @ read control register
@@ -273,7 +268,7 @@
b __v6_setup
.long cpu_arch_name
.long cpu_elf_name
- .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_VFP|HWCAP_EDSP|HWCAP_JAVA
+ .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP|HWCAP_JAVA
.long cpu_v6_name
.long v6_processor_functions
.long v6wbi_tlb_fns
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index f08eafb..e26cc1f 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -263,13 +263,24 @@
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 @@
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 @@
(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;
}