Doh, now I need another change to deal with older compilers
diff --git a/arm/Makefile.arm b/arm/Makefile.arm
index 43b4be1e05eeb..d379a28007493 100644
--- a/arm/Makefile.arm
+++ b/arm/Makefile.arm
@@ -5,7 +5,7 @@
#
bits = 32
ldarch = elf32-littlearm
-machine = -marm
+machine = -marm -mfpu=vfp
# stack.o relies on frame pointers.
KEEP_FRAME_POINTER := y
I'll send a v2 now.
On Thu, Nov 28, 2019 at 03:34:21PM +0100, Andrew Jones wrote:
> Variable argument macros frequently depend on floating point
> registers. Indeed we needed to enable the VFP for arm64 since its
> introduction in order to use printf and the like. Somehow we
> didn't need to do that for arm32 until recently when compiling
> with GCC 9.
>
> Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx>
> ---
>
> CC'ing Thomas because I think he had to workaround travis tests
> failing due to this issue once. Maybe travis can now be
> un-worked-around?
>
>
> arm/cstart.S | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/arm/cstart.S b/arm/cstart.S
> index 114726feab82..bc6219d8a3ee 100644
> --- a/arm/cstart.S
> +++ b/arm/cstart.S
> @@ -50,10 +50,11 @@ start:
> mov r0, r2
> push {r0-r1}
>
> - /* set up vector table and mode stacks */
> + /* set up vector table, mode stacks, and enable the VFP */
> mov r0, lr @ lr is stack top (see above),
> @ which is the exception stacks base
> bl exceptions_init
> + bl enable_vfp
>
> /* complete setup */
> pop {r0-r1}
> @@ -100,6 +101,16 @@ exceptions_init:
> isb
> mov pc, lr
>
> +enable_vfp:
> + /* Enable full access to CP10 and CP11: */
> + mov r0, #(3 << 22 | 3 << 20)
> + mcr p15, 0, r0, c1, c0, 2
> + isb
> + /* Set the FPEXC.EN bit to enable Advanced SIMD and VFP: */
> + mov r0, #(1 << 30)
> + vmsr fpexc, r0
> + mov pc, lr
> +
> .text
>
> .global get_mmu_off
> @@ -130,6 +141,7 @@ secondary_entry:
> ldr r0, [r1]
> mov sp, r0
> bl exceptions_init
> + bl enable_vfp
>
> /* finish init in C code */
> bl secondary_cinit
> --
> 2.21.0
>
