1 files changed, 65 insertions, 2 deletions

diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 9f476a1be2ca..01599c4ef726 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -266,7 +266,7 @@ void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs)
 		 * on VFP subarch 1.
 		 */
 		 vfp_raise_exceptions(VFP_EXCEPTION_ERROR, trigger, fpscr, regs);
-		 return;
+		goto exit;
 	}
 
 	/*
@@ -297,7 +297,7 @@ void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs)
 	 * the FPEXC.FP2V bit is valid only if FPEXC.EX is 1.
 	 */
 	if (fpexc ^ (FPEXC_EX | FPEXC_FP2V))
-		return;
+		goto exit;
 
 	/*
 	 * The barrier() here prevents fpinst2 being read
@@ -310,6 +310,8 @@ void VFP_bounce(u32 trigger, u32 fpexc, struct pt_regs *regs)
 	exceptions = vfp_emulate_instruction(trigger, orig_fpscr, regs);
 	if (exceptions)
 		vfp_raise_exceptions(exceptions, trigger, orig_fpscr, regs);
+ exit:
+	preempt_enable();
 }
 
 static void vfp_enable(void *unused)
@@ -377,6 +379,55 @@ static void vfp_pm_init(void)
 static inline void vfp_pm_init(void) { }
 #endif /* CONFIG_PM */
 
+/*
+ * Synchronise the hardware VFP state of a thread other than current with the
+ * saved one. This function is used by the ptrace mechanism.
+ */
+#ifdef CONFIG_SMP
+void vfp_sync_state(struct thread_info *thread)
+{
+	/*
+	 * On SMP systems, the VFP state is automatically saved at every
+	 * context switch. We mark the thread VFP state as belonging to a
+	 * non-existent CPU so that the saved one will be reloaded when
+	 * needed.
+	 */
+	thread->vfpstate.hard.cpu = NR_CPUS;
+}
+#else
+void vfp_sync_state(struct thread_info *thread)
+{
+	unsigned int cpu = get_cpu();
+	u32 fpexc = fmrx(FPEXC);
+
+	/*
+	 * If VFP is enabled, the previous state was already saved and
+	 * last_VFP_context updated.
+	 */
+	if (fpexc & FPEXC_EN)
+		goto out;
+
+	if (!last_VFP_context[cpu])
+		goto out;
+
+	/*
+	 * Save the last VFP state on this CPU.
+	 */
+	fmxr(FPEXC, fpexc | FPEXC_EN);
+	vfp_save_state(last_VFP_context[cpu], fpexc);
+	fmxr(FPEXC, fpexc);
+
+	/*
+	 * Set the context to NULL to force a reload the next time the thread
+	 * uses the VFP.
+	 */
+	last_VFP_context[cpu] = NULL;
+
+out:
+	put_cpu();
+}
+#endif
+
 #include <linux/smp.h>
 
 /*
@@ -427,6 +478,18 @@ static int __init vfp_init(void)
 		 * in place; report VFP support to userspace.
 		 */
 		elf_hwcap |= HWCAP_VFP;
+#ifdef CONFIG_VFPv3
+		if (VFP_arch >= 3) {
+			elf_hwcap |= HWCAP_VFPv3;
+
+			/*
+			 * Check for VFPv3 D16. CPUs in this configuration
+			 * only have 16 x 64bit registers.
+			 */
+			if (((fmrx(MVFR0) & MVFR0_A_SIMD_MASK)) == 1)
+				elf_hwcap |= HWCAP_VFPv3D16;
+		}
+#endif
 #ifdef CONFIG_NEON
 		/*
 		 * Check for the presence of the Advanced SIMD