[U-Boot] [PATCH v3 45/62] x86: Don't build call64 and setjmp on 64-bit

[Simon Glass]

These are currently not supported. Calling 64-bit code from 64-bit U-Boot is
much simpler, so this code is not needed. setjmp() is not yet implemented for
64-bit.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v3:
- Add a TODO indicating that booting 32- and 64-bit kernels should be supported

Changes in v2: None

 arch/x86/cpu/Makefile | 6 +++++-
 arch/x86/lib/bootm.c  | 7 +++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile
index 7f89ff047fa..f0135a759e9 100644
--- a/arch/x86/cpu/Makefile
+++ b/arch/x86/cpu/Makefile
@@ -14,7 +14,11 @@ else
 extra-y	= start.o
 endif
 extra-$(CONFIG_$(SPL_)X86_16BIT_INIT) += resetvec.o start16.o
-obj-y	+= cpu.o cpu_x86.o call64.o setjmp.o
+ifndef CONFIG_$(SPL_)X86_64
+obj-y	+= call64.o setjmp.o
+endif
+
+obj-y	+= cpu.o cpu_x86.o
 
 AFLAGS_REMOVE_call32.o := -mregparm=3 \
 	$(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32)
diff --git a/arch/x86/lib/bootm.c b/arch/x86/lib/bootm.c
index e5e63f6888e..3c3d9e1e800 100644
--- a/arch/x86/lib/bootm.c
+++ b/arch/x86/lib/bootm.c
@@ -155,7 +155,14 @@ int boot_linux_kernel(ulong setup_base, ulong load_address, bool image_64bit)
 			puts("Cannot boot 64-bit kernel on 32-bit machine\n");
 			return -EFAULT;
 		}
+		/* At present 64-bit U-Boot does not support booting a
+		 * kernel.
+		 * TODO(sjg at chromium.org): Support booting both 32-bit and
+		 * 64-bit kernels from 64-bit U-Boot.
+		 */
+#if !CONFIG_IS_ENABLED(X86_64)
 		return cpu_jump_to_64bit(setup_base, load_address);
+#endif
 	} else {
 		/*
 		* Set %ebx, %ebp, and %edi to 0, %esi to point to the
-- 
2.11.0.483.g087da7b7c-goog