Hi Julien, On Wed, Apr 20, 2016 at 03:44:09PM +0100, Julien Grall wrote: >Hello Peng, > >On 20/04/16 14:54, Peng Fan wrote: >>Use shift operator, but not muliplication. >>No function change. > >Why? The compiler will calculate the address at compilation time.
Yeah. The compiler will do this. I just think in asm, we rarely use multiplication. In this file, there is "cmp x1, #(LPAE_ENTRIES<<3)", here use shift operator but not multiplication. Thanks, Peng. > >Regards, > >>Signed-off-by: Peng Fan <van.free...@gmail.com> >>Cc: Stefano Stabellini <sstabell...@kernel.org> >>Cc: Julien Grall <julien.gr...@arm.com> >>--- >> xen/arch/arm/arm64/head.S | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >>diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S >>index 05e3db0..ad6e593 100644 >>--- a/xen/arch/arm/arm64/head.S >>+++ b/xen/arch/arm/arm64/head.S >>@@ -524,7 +524,7 @@ paging: >> lsl x2, x2, #THIRD_SHIFT /* 4K aligned paddr of UART */ >> mov x3, #PT_DEV_L3 >> orr x2, x2, x3 /* x2 := 4K dev map including UART */ >>- str x2, [x1, #(FIXMAP_CONSOLE*8)] /* Map it in the first fixmap's >>slot */ >>+ str x2, [x1, #(FIXMAP_CONSOLE << 3)] /* Map it in the first >>fixmap's slot */ >> 1: >> >> /* Map fixmap into boot_second */ >> > >-- >Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
