nds32: Enable FPU if the version of CPU supported

[u-boot] / arch / nds32 / cpu / n1213 / ag102 / lowlevel_init.S

diff --git a/arch/nds32/cpu/n1213/ag102/lowlevel_init.S b/arch/nds32/cpu/n1213/ag102/lowlevel_init.S
index d842afa4ba6372664f762d034fac7d6081c5e340..d3b9e1636aa4841160863185041cdcef152944c3 100644 (file)
--- a/arch/nds32/cpu/n1213/ag102/lowlevel_init.S
+++ b/arch/nds32/cpu/n1213/ag102/lowlevel_init.S
@@ -114,6 +114,11 @@ lowlevel_init:
        led     0x20
        jal     remap
 
+#if (defined(NDS32_EXT_FPU_DP) || defined(NDS32_EXT_FPU_SP))
+       led     0x2f
+       jal     enable_fpu
+#endif
+
        led     0x30
        ret     $r10
 
@@ -289,6 +294,27 @@ relo_base:
 2:
        ret
 
+       /*
+        * enable_fpu:
+        *  Some of Andes CPU version support FPU coprocessor, if so,
+        *  and toolchain support FPU instruction set, we should enable it.
+        */
+#if (defined(NDS32_EXT_FPU_DP) || defined(NDS32_EXT_FPU_SP))
+enable_fpu:
+       mfsr    $r0, $CPU_VER     /* enable FPU if it exists */
+       srli    $r0, $r0, 3
+       andi    $r0, $r0, 1
+       beqz    $r0, 1f           /* skip if no COP */
+       mfsr    $r0, $FUCOP_EXIST
+       srli    $r0, $r0, 31
+       beqz    $r0, 1f           /* skip if no FPU */
+       mfsr    $r0, $FUCOP_CTL
+       ori     $r0, $r0, 1
+       mtsr    $r0, $FUCOP_CTL
+1:
+       ret
+#endif
+
 .globl show_led
 show_led:
     li      $r8, (CONFIG_DEBUG_LED)