Remove excessive empty lines from arm64_relocate_new_kernel. Also, use comments on the same lines with instructions where appropriate.
Change ENDPROC to END it never returns. copy_page(dest, src, tmps...) Increments dest and src by PAGE_SIZE, so no need to store dest prior to calling copy_page and increment it after. Also, src is not used after a copy, not need to copy either. Call raw_dcache_line_size() only when relocation is actually going to happen. Since '.align 3' is intended to align globals at the end of the file, move it there. Signed-off-by: Pavel Tatashin <[email protected]> --- arch/arm64/kernel/relocate_kernel.S | 50 +++++++---------------------- 1 file changed, 11 insertions(+), 39 deletions(-) diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S index c1d7db71a726..e9c974ea4717 100644 --- a/arch/arm64/kernel/relocate_kernel.S +++ b/arch/arm64/kernel/relocate_kernel.S @@ -8,7 +8,6 @@ #include <linux/kexec.h> #include <linux/linkage.h> - #include <asm/assembler.h> #include <asm/kexec.h> #include <asm/page.h> @@ -17,25 +16,21 @@ /* * arm64_relocate_new_kernel - Put a 2nd stage image in place and boot it. * - * The memory that the old kernel occupies may be overwritten when coping the + * The memory that the old kernel occupies may be overwritten when copying the * new image to its final location. To assure that the * arm64_relocate_new_kernel routine which does that copy is not overwritten, * all code and data needed by arm64_relocate_new_kernel must be between the * symbols arm64_relocate_new_kernel and arm64_relocate_new_kernel_end. The * machine_kexec() routine will copy arm64_relocate_new_kernel to the kexec - * control_code_page, a special page which has been set up to be preserved - * during the copy operation. + * safe memory that has been set up to be preserved during the copy operation. */ ENTRY(arm64_relocate_new_kernel) - /* Setup the list loop variables. */ mov x18, x2 /* x18 = dtb address */ mov x17, x1 /* x17 = kimage_start */ mov x16, x0 /* x16 = kimage_head */ - raw_dcache_line_size x15, x0 /* x15 = dcache line size */ mov x14, xzr /* x14 = entry ptr */ mov x13, xzr /* x13 = copy dest */ - /* Clear the sctlr_el2 flags. */ mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 @@ -46,14 +41,11 @@ ENTRY(arm64_relocate_new_kernel) pre_disable_mmu_workaround msr sctlr_el2, x0 isb -1: - - /* Check if the new image needs relocation. */ +1: /* Check if the new image needs relocation. */ tbnz x16, IND_DONE_BIT, .Ldone - + raw_dcache_line_size x15, x1 /* x15 = dcache line size */ .Lloop: and x12, x16, PAGE_MASK /* x12 = addr */ - /* Test the entry flags. */ .Ltest_source: tbz x16, IND_SOURCE_BIT, .Ltest_indirection @@ -69,34 +61,18 @@ ENTRY(arm64_relocate_new_kernel) b.lo 2b dsb sy - mov x20, x13 - mov x21, x12 - copy_page x20, x21, x0, x1, x2, x3, x4, x5, x6, x7 - - /* dest += PAGE_SIZE */ - add x13, x13, PAGE_SIZE + copy_page x13, x12, x0, x1, x2, x3, x4, x5, x6, x7 b .Lnext - .Ltest_indirection: tbz x16, IND_INDIRECTION_BIT, .Ltest_destination - - /* ptr = addr */ - mov x14, x12 + mov x14, x12 /* ptr = addr */ b .Lnext - .Ltest_destination: tbz x16, IND_DESTINATION_BIT, .Lnext - - /* dest = addr */ - mov x13, x12 - + mov x13, x12 /* dest = addr */ .Lnext: - /* entry = *ptr++ */ - ldr x16, [x14], #8 - - /* while (!(entry & DONE)) */ - tbz x16, IND_DONE_BIT, .Lloop - + ldr x16, [x14], #8 /* entry = *ptr++ */ + tbz x16, IND_DONE_BIT, .Lloop /* while (!(entry & DONE)) */ .Ldone: /* wait for writes from copy_page to finish */ dsb nsh @@ -110,16 +86,12 @@ ENTRY(arm64_relocate_new_kernel) mov x2, xzr mov x3, xzr br x17 - -ENDPROC(arm64_relocate_new_kernel) - .ltorg - -.align 3 /* To keep the 64-bit values below naturally aligned. */ +END(arm64_relocate_new_kernel) .Lcopy_end: .org KEXEC_CONTROL_PAGE_SIZE - +.align 3 /* To keep the 64-bit values below naturally aligned. */ /* * arm64_relocate_new_kernel_size - Number of bytes to copy to the * control_code_page. -- 2.23.0
