Date: Tue, 13 Oct 2020 16:51:05 +0000 (UTC) From: Andrew Turner <andrew@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r366670 - head/stand/efi/loader/arch/arm64 Message-ID: <202010131651.09DGp514094222@repo.freebsd.org>
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Author: andrew Date: Tue Oct 13 16:51:05 2020 New Revision: 366670 URL: https://svnweb.freebsd.org/changeset/base/366670 Log: 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 Modified: head/stand/efi/loader/arch/arm64/start.S Modified: head/stand/efi/loader/arch/arm64/start.S ============================================================================== --- head/stand/efi/loader/arch/arm64/start.S Tue Oct 13 16:19:21 2020 (r366669) +++ head/stand/efi/loader/arch/arm64/start.S Tue Oct 13 16:51:05 2020 (r366670) @@ -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
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