Date: Wed, 15 Nov 2023 18:12:20 GMT From: Andrew Turner <andrew@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 61f14f1da37b - main - arm64: Clean up finding our load address Message-ID: <202311151812.3AFICKgF077519@gitrepo.freebsd.org>
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The branch main has been updated by andrew: URL: https://cgit.FreeBSD.org/src/commit/?id=61f14f1da37b4e6db8f9efe40c6b544c855fb9bd commit 61f14f1da37b4e6db8f9efe40c6b544c855fb9bd Author: Andrew Turner <andrew@FreeBSD.org> AuthorDate: 2023-11-13 15:39:06 +0000 Commit: Andrew Turner <andrew@FreeBSD.org> CommitDate: 2023-11-15 18:05:08 +0000 arm64: Clean up finding our load address Use the linker to pre-calculate the offset of a known symbol from KERNBASE, and use this to find the physical address KERNBASE should map to. Sponsored by: Arm Ltd Differential Revision: https://reviews.freebsd.org/D42568 --- sys/arm64/arm64/locore.S | 18 +++++------------- 1 file changed, 5 insertions(+), 13 deletions(-) diff --git a/sys/arm64/arm64/locore.S b/sys/arm64/arm64/locore.S index cea2f690b60f..ffd13610ec02 100644 --- a/sys/arm64/arm64/locore.S +++ b/sys/arm64/arm64/locore.S @@ -359,21 +359,13 @@ LEND(drop_to_el1) * Get the physical address the kernel was loaded at. */ LENTRY(get_load_phys_addr) + /* Load the offset of get_load_phys_addr from KERNBASE */ + ldr x28, =(get_load_phys_addr - KERNBASE) /* Load the physical address of virt_map */ - adrp x29, virt_map - add x29, x29, :lo12:virt_map - /* Load the virtual address of virt_map stored in virt_map */ - ldr x28, [x29] - /* Find PA - VA as PA' = VA' - VA + PA = VA' + (PA - VA) = VA' + x29 */ - sub x29, x29, x28 - /* Find the load address for the kernel */ - mov x28, #(KERNBASE) - add x28, x28, x29 + adr x29, get_load_phys_addr + /* Find the physical address of KERNBASE, i.e. our load address */ + sub x28, x29, x28 ret - - .align 3 -virt_map: - .quad virt_map LEND(get_load_phys_addr) /*
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