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OpenCloudOS-Kernel/arch/arm64/kernel/efi-entry.S

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-04 16:11:33 +08:00
/* SPDX-License-Identifier: GPL-2.0-only */
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
/*
* EFI entry point.
*
* Copyright (C) 2013, 2014 Red Hat, Inc.
* Author: Mark Salter <msalter@redhat.com>
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
__INIT
efi/arm64: Clean EFI stub exit code from cache instead of avoiding it Commit 9f9223778 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") modified the handover code written in assembler, and for maintainability, aligned the logic with the logic used in the 32-bit ARM version, which is to avoid cache maintenance on the remaining instructions in the subroutine that will be executed with the MMU and caches off, and instead, branch into the relocated copy of the kernel image. However, this assumes that this copy is executable, and this means we expect EFI_LOADER_DATA regions to be executable as well, which is not a reasonable assumption to make, even if this is true for most UEFI implementations today. So change this back, and add a __clean_dcache_area_poc() call to cover the remaining code in the subroutine. While at it, switch the other call site over to __clean_dcache_area_poc() as well, and clean up the terminology in comments to avoid using 'flush' in the context of cache maintenance. Also, let's switch to the new style asm annotations. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-6-ardb@kernel.org
2020-02-28 20:14:07 +08:00
SYM_CODE_START(efi_enter_kernel)
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
/*
efi/libstub: Add missing prototype for PE/COFF entry point Fix a missing prototype warning by adding a forward declaration for the PE/COFF entrypoint, and while at it, align the function name between the x86 and ARM versions of the stub. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-05-23 17:01:57 +08:00
* efi_pe_entry() will have copied the kernel image if necessary and we
efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint Expose efi_entry() as the PE/COFF entrypoint directly, instead of jumping into a wrapper that fiddles with stack buffers and other stuff that the compiler is much better at. The only reason this code exists is to obtain a pointer to the base of the image, but we can get the same value from the loaded_image protocol, which we already need for other reasons anyway. Update the return type as well, to make it consistent with what is required for a PE/COFF executable entrypoint. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-17 19:44:37 +08:00
* end up here with device tree address in x1 and the kernel entry
* point stored in x0. Save those values in registers which are
* callee preserved.
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
*/
arm64: rename stext to primary_entry For historical reasons, the primary entry routine living somewhere in the inittext section is called stext(), which is confusing, given that there is also a section marker called _stext which lives at a fixed offset in the image (either 64 or 4096 bytes, depending on whether CONFIG_EFI is enabled) Let's rename stext to primary_entry(), which is a better description and reflects the secondary_entry() routine that already exists for SMP boot. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20200326171423.3080-1-ardb@kernel.org Reviwed-by: Mark Brown <broonie@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2020-03-27 01:14:23 +08:00
ldr w2, =primary_entry_offset
efi/arm64: Clean EFI stub exit code from cache instead of avoiding it Commit 9f9223778 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") modified the handover code written in assembler, and for maintainability, aligned the logic with the logic used in the 32-bit ARM version, which is to avoid cache maintenance on the remaining instructions in the subroutine that will be executed with the MMU and caches off, and instead, branch into the relocated copy of the kernel image. However, this assumes that this copy is executable, and this means we expect EFI_LOADER_DATA regions to be executable as well, which is not a reasonable assumption to make, even if this is true for most UEFI implementations today. So change this back, and add a __clean_dcache_area_poc() call to cover the remaining code in the subroutine. While at it, switch the other call site over to __clean_dcache_area_poc() as well, and clean up the terminology in comments to avoid using 'flush' in the context of cache maintenance. Also, let's switch to the new style asm annotations. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-6-ardb@kernel.org
2020-02-28 20:14:07 +08:00
add x19, x0, x2 // relocated Image entrypoint
efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint Expose efi_entry() as the PE/COFF entrypoint directly, instead of jumping into a wrapper that fiddles with stack buffers and other stuff that the compiler is much better at. The only reason this code exists is to obtain a pointer to the base of the image, but we can get the same value from the loaded_image protocol, which we already need for other reasons anyway. Update the return type as well, to make it consistent with what is required for a PE/COFF executable entrypoint. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-17 19:44:37 +08:00
mov x20, x1 // DTB address
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
arm64: efi: Fix stub cache maintenance While efi-entry.S mentions that efi_entry() will have relocated the kernel image, it actually means that efi_entry will have placed a copy of the kernel in the appropriate location, and until this is branched to at the end of efi_entry.S, all instructions are executed from the original image. Thus while the flush in efi_entry.S does ensure that the copy is visible to noncacheable accesses, it does not guarantee that this is true for the image instructions are being executed from. This could have disasterous effects when the MMU and caches are disabled if the image has not been naturally evicted to the PoC. Additionally, due to a missing dsb following the ic ialluis, the new kernel image is not necessarily clean in the I-cache when it is branched to, with similar potentially disasterous effects. This patch adds additional flushing to ensure that the currently executing stub text is flushed to the PoC and is thus visible to noncacheable accesses. As it is placed after the instructions cache maintenance for the new image and __flush_dcache_area already contains a dsb, we do not need to add a separate barrier to ensure completion of the icache maintenance. Comments are updated to clarify the situation with regard to the two images and the maintenance required for both. Fixes: 3c7f255039a2ad6ee1e3890505caf0d029b22e29 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Joel Schopp <joel.schopp@amd.com> Reviewed-by: Roy Franz <roy.franz@linaro.org> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ian Campbell <ijc@hellion.org.uk> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-11-13 20:22:01 +08:00
/*
efi/arm64: Clean EFI stub exit code from cache instead of avoiding it Commit 9f9223778 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") modified the handover code written in assembler, and for maintainability, aligned the logic with the logic used in the 32-bit ARM version, which is to avoid cache maintenance on the remaining instructions in the subroutine that will be executed with the MMU and caches off, and instead, branch into the relocated copy of the kernel image. However, this assumes that this copy is executable, and this means we expect EFI_LOADER_DATA regions to be executable as well, which is not a reasonable assumption to make, even if this is true for most UEFI implementations today. So change this back, and add a __clean_dcache_area_poc() call to cover the remaining code in the subroutine. While at it, switch the other call site over to __clean_dcache_area_poc() as well, and clean up the terminology in comments to avoid using 'flush' in the context of cache maintenance. Also, let's switch to the new style asm annotations. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-6-ardb@kernel.org
2020-02-28 20:14:07 +08:00
* Clean the copied Image to the PoC, and ensure it is not shadowed by
arm64: efi: Fix stub cache maintenance While efi-entry.S mentions that efi_entry() will have relocated the kernel image, it actually means that efi_entry will have placed a copy of the kernel in the appropriate location, and until this is branched to at the end of efi_entry.S, all instructions are executed from the original image. Thus while the flush in efi_entry.S does ensure that the copy is visible to noncacheable accesses, it does not guarantee that this is true for the image instructions are being executed from. This could have disasterous effects when the MMU and caches are disabled if the image has not been naturally evicted to the PoC. Additionally, due to a missing dsb following the ic ialluis, the new kernel image is not necessarily clean in the I-cache when it is branched to, with similar potentially disasterous effects. This patch adds additional flushing to ensure that the currently executing stub text is flushed to the PoC and is thus visible to noncacheable accesses. As it is placed after the instructions cache maintenance for the new image and __flush_dcache_area already contains a dsb, we do not need to add a separate barrier to ensure completion of the icache maintenance. Comments are updated to clarify the situation with regard to the two images and the maintenance required for both. Fixes: 3c7f255039a2ad6ee1e3890505caf0d029b22e29 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Joel Schopp <joel.schopp@amd.com> Reviewed-by: Roy Franz <roy.franz@linaro.org> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ian Campbell <ijc@hellion.org.uk> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-11-13 20:22:01 +08:00
* stale icache entries from before relocation.
*/
efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint Expose efi_entry() as the PE/COFF entrypoint directly, instead of jumping into a wrapper that fiddles with stack buffers and other stuff that the compiler is much better at. The only reason this code exists is to obtain a pointer to the base of the image, but we can get the same value from the loaded_image protocol, which we already need for other reasons anyway. Update the return type as well, to make it consistent with what is required for a PE/COFF executable entrypoint. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-17 19:44:37 +08:00
ldr w1, =kernel_size
efi/arm64: Clean EFI stub exit code from cache instead of avoiding it Commit 9f9223778 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") modified the handover code written in assembler, and for maintainability, aligned the logic with the logic used in the 32-bit ARM version, which is to avoid cache maintenance on the remaining instructions in the subroutine that will be executed with the MMU and caches off, and instead, branch into the relocated copy of the kernel image. However, this assumes that this copy is executable, and this means we expect EFI_LOADER_DATA regions to be executable as well, which is not a reasonable assumption to make, even if this is true for most UEFI implementations today. So change this back, and add a __clean_dcache_area_poc() call to cover the remaining code in the subroutine. While at it, switch the other call site over to __clean_dcache_area_poc() as well, and clean up the terminology in comments to avoid using 'flush' in the context of cache maintenance. Also, let's switch to the new style asm annotations. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-6-ardb@kernel.org
2020-02-28 20:14:07 +08:00
bl __clean_dcache_area_poc
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
ic ialluis
arm64: efi: Fix stub cache maintenance While efi-entry.S mentions that efi_entry() will have relocated the kernel image, it actually means that efi_entry will have placed a copy of the kernel in the appropriate location, and until this is branched to at the end of efi_entry.S, all instructions are executed from the original image. Thus while the flush in efi_entry.S does ensure that the copy is visible to noncacheable accesses, it does not guarantee that this is true for the image instructions are being executed from. This could have disasterous effects when the MMU and caches are disabled if the image has not been naturally evicted to the PoC. Additionally, due to a missing dsb following the ic ialluis, the new kernel image is not necessarily clean in the I-cache when it is branched to, with similar potentially disasterous effects. This patch adds additional flushing to ensure that the currently executing stub text is flushed to the PoC and is thus visible to noncacheable accesses. As it is placed after the instructions cache maintenance for the new image and __flush_dcache_area already contains a dsb, we do not need to add a separate barrier to ensure completion of the icache maintenance. Comments are updated to clarify the situation with regard to the two images and the maintenance required for both. Fixes: 3c7f255039a2ad6ee1e3890505caf0d029b22e29 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Joel Schopp <joel.schopp@amd.com> Reviewed-by: Roy Franz <roy.franz@linaro.org> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ian Campbell <ijc@hellion.org.uk> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-11-13 20:22:01 +08:00
/*
efi/arm64: Clean EFI stub exit code from cache instead of avoiding it Commit 9f9223778 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") modified the handover code written in assembler, and for maintainability, aligned the logic with the logic used in the 32-bit ARM version, which is to avoid cache maintenance on the remaining instructions in the subroutine that will be executed with the MMU and caches off, and instead, branch into the relocated copy of the kernel image. However, this assumes that this copy is executable, and this means we expect EFI_LOADER_DATA regions to be executable as well, which is not a reasonable assumption to make, even if this is true for most UEFI implementations today. So change this back, and add a __clean_dcache_area_poc() call to cover the remaining code in the subroutine. While at it, switch the other call site over to __clean_dcache_area_poc() as well, and clean up the terminology in comments to avoid using 'flush' in the context of cache maintenance. Also, let's switch to the new style asm annotations. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-6-ardb@kernel.org
2020-02-28 20:14:07 +08:00
* Clean the remainder of this routine to the PoC
* so that we can safely disable the MMU and caches.
arm64: efi: Fix stub cache maintenance While efi-entry.S mentions that efi_entry() will have relocated the kernel image, it actually means that efi_entry will have placed a copy of the kernel in the appropriate location, and until this is branched to at the end of efi_entry.S, all instructions are executed from the original image. Thus while the flush in efi_entry.S does ensure that the copy is visible to noncacheable accesses, it does not guarantee that this is true for the image instructions are being executed from. This could have disasterous effects when the MMU and caches are disabled if the image has not been naturally evicted to the PoC. Additionally, due to a missing dsb following the ic ialluis, the new kernel image is not necessarily clean in the I-cache when it is branched to, with similar potentially disasterous effects. This patch adds additional flushing to ensure that the currently executing stub text is flushed to the PoC and is thus visible to noncacheable accesses. As it is placed after the instructions cache maintenance for the new image and __flush_dcache_area already contains a dsb, we do not need to add a separate barrier to ensure completion of the icache maintenance. Comments are updated to clarify the situation with regard to the two images and the maintenance required for both. Fixes: 3c7f255039a2ad6ee1e3890505caf0d029b22e29 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Joel Schopp <joel.schopp@amd.com> Reviewed-by: Roy Franz <roy.franz@linaro.org> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ian Campbell <ijc@hellion.org.uk> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-11-13 20:22:01 +08:00
*/
efi/arm64: Clean EFI stub exit code from cache instead of avoiding it Commit 9f9223778 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") modified the handover code written in assembler, and for maintainability, aligned the logic with the logic used in the 32-bit ARM version, which is to avoid cache maintenance on the remaining instructions in the subroutine that will be executed with the MMU and caches off, and instead, branch into the relocated copy of the kernel image. However, this assumes that this copy is executable, and this means we expect EFI_LOADER_DATA regions to be executable as well, which is not a reasonable assumption to make, even if this is true for most UEFI implementations today. So change this back, and add a __clean_dcache_area_poc() call to cover the remaining code in the subroutine. While at it, switch the other call site over to __clean_dcache_area_poc() as well, and clean up the terminology in comments to avoid using 'flush' in the context of cache maintenance. Also, let's switch to the new style asm annotations. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-6-ardb@kernel.org
2020-02-28 20:14:07 +08:00
adr x0, 0f
ldr w1, 3f
bl __clean_dcache_area_poc
efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint Expose efi_entry() as the PE/COFF entrypoint directly, instead of jumping into a wrapper that fiddles with stack buffers and other stuff that the compiler is much better at. The only reason this code exists is to obtain a pointer to the base of the image, but we can get the same value from the loaded_image protocol, which we already need for other reasons anyway. Update the return type as well, to make it consistent with what is required for a PE/COFF executable entrypoint. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-17 19:44:37 +08:00
0:
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
/* Turn off Dcache and MMU */
mrs x0, CurrentEL
arm64: fix el2_setup check of CurrentEL The CurrentEL system register reports the Current Exception Level of the CPU. It doesn't say anything about the stack handling, and yet we compare it to PSR_MODE_EL2t and PSR_MODE_EL2h. It works by chance because PSR_MODE_EL2t happens to match the right bits, but that's otherwise a very bad idea. Just check for the EL value instead. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> [catalin.marinas@arm.com: fixed arch/arm64/kernel/efi-entry.S] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-06-06 21:16:21 +08:00
cmp x0, #CurrentEL_EL2
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
b.ne 1f
mrs x0, sctlr_el2
bic x0, x0, #1 << 0 // clear SCTLR.M
bic x0, x0, #1 << 2 // clear SCTLR.C
arm64: Add software workaround for Falkor erratum 1041 The ARM architecture defines the memory locations that are permitted to be accessed as the result of a speculative instruction fetch from an exception level for which all stages of translation are disabled. Specifically, the core is permitted to speculatively fetch from the 4KB region containing the current program counter 4K and next 4K. When translation is changed from enabled to disabled for the running exception level (SCTLR_ELn[M] changed from a value of 1 to 0), the Falkor core may errantly speculatively access memory locations outside of the 4KB region permitted by the architecture. The errant memory access may lead to one of the following unexpected behaviors. 1) A System Error Interrupt (SEI) being raised by the Falkor core due to the errant memory access attempting to access a region of memory that is protected by a slave-side memory protection unit. 2) Unpredictable device behavior due to a speculative read from device memory. This behavior may only occur if the instruction cache is disabled prior to or coincident with translation being changed from enabled to disabled. The conditions leading to this erratum will not occur when either of the following occur: 1) A higher exception level disables translation of a lower exception level (e.g. EL2 changing SCTLR_EL1[M] from a value of 1 to 0). 2) An exception level disabling its stage-1 translation if its stage-2 translation is enabled (e.g. EL1 changing SCTLR_EL1[M] from a value of 1 to 0 when HCR_EL2[VM] has a value of 1). To avoid the errant behavior, software must execute an ISB immediately prior to executing the MSR that will change SCTLR_ELn[M] from 1 to 0. Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-12-12 06:42:32 +08:00
pre_disable_mmu_workaround
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
msr sctlr_el2, x0
isb
b 2f
1:
mrs x0, sctlr_el1
bic x0, x0, #1 << 0 // clear SCTLR.M
bic x0, x0, #1 << 2 // clear SCTLR.C
arm64: Add software workaround for Falkor erratum 1041 The ARM architecture defines the memory locations that are permitted to be accessed as the result of a speculative instruction fetch from an exception level for which all stages of translation are disabled. Specifically, the core is permitted to speculatively fetch from the 4KB region containing the current program counter 4K and next 4K. When translation is changed from enabled to disabled for the running exception level (SCTLR_ELn[M] changed from a value of 1 to 0), the Falkor core may errantly speculatively access memory locations outside of the 4KB region permitted by the architecture. The errant memory access may lead to one of the following unexpected behaviors. 1) A System Error Interrupt (SEI) being raised by the Falkor core due to the errant memory access attempting to access a region of memory that is protected by a slave-side memory protection unit. 2) Unpredictable device behavior due to a speculative read from device memory. This behavior may only occur if the instruction cache is disabled prior to or coincident with translation being changed from enabled to disabled. The conditions leading to this erratum will not occur when either of the following occur: 1) A higher exception level disables translation of a lower exception level (e.g. EL2 changing SCTLR_EL1[M] from a value of 1 to 0). 2) An exception level disabling its stage-1 translation if its stage-2 translation is enabled (e.g. EL1 changing SCTLR_EL1[M] from a value of 1 to 0 when HCR_EL2[VM] has a value of 1). To avoid the errant behavior, software must execute an ISB immediately prior to executing the MSR that will change SCTLR_ELn[M] from 1 to 0. Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-12-12 06:42:32 +08:00
pre_disable_mmu_workaround
arm64: efi: add EFI stub This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-16 10:47:52 +08:00
msr sctlr_el1, x0
isb
2:
/* Jump to kernel entry point */
mov x0, x20
mov x1, xzr
mov x2, xzr
mov x3, xzr
efi/arm64: Clean EFI stub exit code from cache instead of avoiding it Commit 9f9223778 ("efi/libstub/arm: Make efi_entry() an ordinary PE/COFF entrypoint") modified the handover code written in assembler, and for maintainability, aligned the logic with the logic used in the 32-bit ARM version, which is to avoid cache maintenance on the remaining instructions in the subroutine that will be executed with the MMU and caches off, and instead, branch into the relocated copy of the kernel image. However, this assumes that this copy is executable, and this means we expect EFI_LOADER_DATA regions to be executable as well, which is not a reasonable assumption to make, even if this is true for most UEFI implementations today. So change this back, and add a __clean_dcache_area_poc() call to cover the remaining code in the subroutine. While at it, switch the other call site over to __clean_dcache_area_poc() as well, and clean up the terminology in comments to avoid using 'flush' in the context of cache maintenance. Also, let's switch to the new style asm annotations. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: David Hildenbrand <david@redhat.com> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20200228121408.9075-6-ardb@kernel.org
2020-02-28 20:14:07 +08:00
br x19
SYM_CODE_END(efi_enter_kernel)
3: .long . - 0b