From 424e5994e63326a42012f003f1174f3c363c7b62 Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Fri, 10 Feb 2012 18:07:07 -0800 Subject: ARM: zImage/virt: hyp mode entry support for the zImage loader The zImage loader needs to turn on the MMU in order to take advantage of caching while decompressing the zImage. Running this in hyp mode would require the LPAE pagetable format to be supported; to avoid this complexity, this patch switches out of hyp mode, and returns back to hyp mode just before booting the kernel. This implementation assumes that the Hyp mode view of memory and the PL1 view of memory are coherent, providing that the MMU and caches are off in both, as required by the boot protocol. The zImage decompression code must drain the write buffer on completion anyway, and entry into Hyp mode should flush any prefetch buffer, avoiding hazards associated with local write buffers and the pipeline. Signed-off-by: Dave Martin Signed-off-by: Marc Zyngier --- arch/arm/boot/compressed/Makefile | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'arch/arm/boot/compressed/Makefile') diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index bb267562e7e..a517153a13e 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -30,6 +30,10 @@ FONTC = $(srctree)/drivers/video/console/font_acorn_8x8.c OBJS += string.o CFLAGS_string.o := -Os +ifeq ($(CONFIG_ARM_VIRT_EXT),y) +OBJS += hyp-stub.o +endif + # # Architecture dependencies # @@ -126,7 +130,7 @@ KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS)) endif ccflags-y := -fpic -fno-builtin -I$(obj) -asflags-y := -Wa,-march=all +asflags-y := -Wa,-march=all -DZIMAGE # Supply kernel BSS size to the decompressor via a linker symbol. KBSS_SZ = $(shell $(CROSS_COMPILE)size $(obj)/../../../../vmlinux | \ @@ -198,3 +202,6 @@ $(obj)/font.c: $(FONTC) $(obj)/vmlinux.lds: $(obj)/vmlinux.lds.in arch/arm/boot/Makefile $(KCONFIG_CONFIG) @sed "$(SEDFLAGS)" < $< > $@ + +$(obj)/hyp-stub.S: $(srctree)/arch/$(SRCARCH)/kernel/hyp-stub.S + $(call cmd,shipped) -- cgit v1.2.3