From b9aa4537b2155a0b0bb419ff05b8da206c02bfbd Mon Sep 17 00:00:00 2001 From: Andrew Turner Date: Tue, 13 Oct 2020 16:51:05 +0000 Subject: [PATCH] Use adrp in the arm64 efi loader On startup the arm64 efi loaders need to know PC-relative addresses. Previously we used the adr instruction to find this address, however this instruction is limited to +/- 1MiB. Switch to adrp to find the 4k page the address is within and an add to set the bottom 12 bits. This lets us address +/- 4GiB which should be large enough for now. Reported by: imp MFC after: 2 weeks Sponsored by: Innovate UK --- stand/efi/loader/arch/arm64/start.S | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/stand/efi/loader/arch/arm64/start.S b/stand/efi/loader/arch/arm64/start.S index bddc2d088a64..675d4e153f36 100644 --- a/stand/efi/loader/arch/arm64/start.S +++ b/stand/efi/loader/arch/arm64/start.S @@ -142,8 +142,10 @@ _start: /* Save the boot params to the stack */ stp x0, x1, [sp, #-16]! - adr x0, __bss_start - adr x1, __bss_end + adrp x0, __bss_start + add x0, x0, :lo12:__bss_start + adrp x1, __bss_end + add x1, x1, :lo12:__bss_end b 2f @@ -153,8 +155,10 @@ _start: cmp x0, x1 b.lo 1b - adr x0, ImageBase - adr x1, _DYNAMIC + adrp x0, ImageBase + add x0, x0, :lo12:ImageBase + adrp x1, _DYNAMIC + add x1, x1, :lo12:_DYNAMIC bl self_reloc @@ -165,7 +169,8 @@ _start: * Load the stack to use. The default stack may be too small for * the lua loader. */ - adr x2, initstack_end + adrp x2, initstack_end + add x2, x2, :lo12:initstack_end mov sp, x2 #endif