ARCv2: fpu: preserve userspace fpu state

[sfrench/cifs-2.6.git] / arch / arc / Kconfig

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index c4409eab07a95ed0355bfa9b6f6c973e1fa45284..fd351001d8b9d125cf561e77961a54b4a8d1f2a9 100644 (file)
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -351,9 +351,8 @@ config NODES_SHIFT
          Accessing memory beyond 1GB (with or w/o PAE) requires 2 memory
          zones.
 
-if ISA_ARCOMPACT
-
 config ARC_COMPACT_IRQ_LEVELS
+       depends on ISA_ARCOMPACT
        bool "Setup Timer IRQ as high Priority"
        # if SMP, LV2 enabled ONLY if ARC implementation has LV2 re-entrancy
        depends on !SMP
@@ -361,14 +360,10 @@ config ARC_COMPACT_IRQ_LEVELS
 config ARC_FPU_SAVE_RESTORE
        bool "Enable FPU state persistence across context switch"
        help
-         Double Precision Floating Point unit had dedicated regs which
-         need to be saved/restored across context-switch.
-         Note that ARC FPU is overly simplistic, unlike say x86, which has
-         hardware pieces to allow software to conditionally save/restore,
-         based on actual usage of FPU by a task. Thus our implemn does
-         this for all tasks in system.
-
-endif #ISA_ARCOMPACT
+         ARCompact FPU has internal registers to assist with Double precision
+         Floating Point operations. There are control and stauts registers
+         for floating point exceptions and rounding modes. These are
+         preserved across task context switch when enabled.
 
 config ARC_CANT_LLSC
        def_bool n