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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH V4 15/15] Add ARM EFI boot support
On Fri, 12 Sep 2014, Roy Franz wrote: > On Fri, Sep 12, 2014 at 10:41 AM, Stefano Stabellini > <stefano.stabellini@xxxxxxxxxxxxx> wrote: > > Please use plain text in emails, no html. > > > > On Thu, 11 Sep 2014, Roy Franz wrote: > >> On Thu, Sep 11, 2014 at 5:49 PM, Stefano Stabellini > >> <stefano.stabellini@xxxxxxxxxxxxx> wrote: > >> On Tue, 9 Sep 2014, Roy Franz wrote: > >> > This patch adds EFI boot support for ARM based on the previous > >> refactoring of > >> > the x86 EFI boot code. All ARM specific code is in the ARM > >> efi-boot.h header > >> > file, with the main EFI entry point common/efi/boot.c. The > >> PE/COFF header is > >> > open-coded in head.S, which allows us to have a single binary be > >> both an EFI > >> > executable and a normal arm64 IMAGE file. There is currently no > >> PE/COFF > >> > toolchain support for arm64, so it is not possible to create the > >> PE/COFF header > >> > in the same manner as on x86. This also simplifies the build as > >> compared to > >> > x86, as we always build the same executable, whereas x86 builds 2. > >> An ARM > >> > version of efi-bind.h is added, which is based on the x86_64 > >> version with the > >> > x86 specific portions removed. The Makefile in common/efi is > >> different for x86 > >> > and ARM, as for ARM we always build in EFI support. > >> > > >> > Signed-off-by: Roy Franz <roy.franz@xxxxxxxxxx> > >> > --- > >> > config/arm64.mk | 1 + > >> > xen/arch/arm/arm64/head.S | 150 ++++++++- > >> > xen/arch/arm/xen.lds.S | 1 + > >> > xen/common/Makefile | 1 + > >> > xen/common/efi/Makefile | 3 + > >> > xen/include/asm-arm/arm64/efibind.h | 216 +++++++++++++ > >> > xen/include/asm-arm/efi-boot.h | 630 > >> ++++++++++++++++++++++++++++++++++++ > >> > xen/include/asm-arm/efi.h | 29 ++ > >> > xen/include/asm-arm/efibind.h | 2 + > >> > xen/include/asm-arm/setup.h | 2 +- > >> > 10 files changed, 1031 insertions(+), 4 deletions(-) > >> > create mode 100644 xen/common/efi/Makefile > >> > create mode 100644 xen/include/asm-arm/arm64/efibind.h > >> > create mode 100644 xen/include/asm-arm/efi-boot.h > >> > create mode 100644 xen/include/asm-arm/efi.h > >> > create mode 100644 xen/include/asm-arm/efibind.h > >> > > >> > diff --git a/config/arm64.mk b/config/arm64.mk > >> > index 15b57a4..e6aab0e 100644 > >> > --- a/config/arm64.mk > >> > +++ b/config/arm64.mk > >> > @@ -1,6 +1,7 @@ > >> > CONFIG_ARM := y > >> > CONFIG_ARM_64 := y > >> > CONFIG_ARM_$(XEN_OS) := y > >> > +CONFIG_EFI := y > >> > > >> > CONFIG_XEN_INSTALL_SUFFIX := > >> > > >> > diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S > >> > index 43b5e72..158c102 100644 > >> > --- a/xen/arch/arm/arm64/head.S > >> > +++ b/xen/arch/arm/arm64/head.S > >> > @@ -24,6 +24,8 @@ > >> > #include <asm/page.h> > >> > #include <asm/asm_defns.h> > >> > #include <asm/early_printk.h> > >> > +#include <efi/efierr.h> > >> > +#include <asm/arm64/efibind.h> > >> > > >> > #define PT_PT 0xf7f /* nG=1 AF=1 SH=11 AP=01 NS=1 ATTR=111 > >> T=1 P=1 */ > >> > #define PT_MEM 0xf7d /* nG=1 AF=1 SH=11 AP=01 NS=1 ATTR=111 > >> T=0 P=1 */ > >> > @@ -104,8 +106,14 @@ GLOBAL(start) > >> > /* > >> > * DO NOT MODIFY. Image header expected by Linux > >> boot-loaders. > >> > */ > >> > - b real_start /* branch to kernel start, > >> magic */ > >> > - .long 0 /* reserved */ > >> > +efi_head: > >> > + /* > >> > + * This add instruction has no meaningful effect except > >> that > >> > + * its opcode forms the magic "MZ" signature of a PE/COFF > >> file > >> > + * that is required for UEFI applications. > >> > + */ > >> > + add x13, x18, #0x16 > >> > + b real_start /* branch to kernel start */ > >> > .quad 0 /* Image load offset from > >> start of RAM */ > >> > .quad 0 /* reserved */ > >> > .quad 0 /* reserved */ > >> > @@ -116,8 +124,113 @@ GLOBAL(start) > >> > .byte 0x52 > >> > .byte 0x4d > >> > .byte 0x64 > >> > - .word 0 /* reserved */ > >> > + .long pe_header - efi_head /* Offset to the PE > >> header. */ > >> > + > >> > + /* > >> > + * Add the PE/COFF header to the file. The address of > >> this header > >> > + * is at offset 0x3c in the file, and is part of Linux > >> "Image" > >> > + * header. The arm64 Linux Image format is designed to > >> support > >> > + * being both an 'Image' format binary and a PE/COFF > >> binary. > >> > + * The PE/COFF format is defined by Microsoft, and is > >> available > >> > + * from: http://msdn.microsoft.com/en-us/gg463119.aspx > >> > + * Version 8.3 adds support for arm64 and UEFI usage. > >> > + */ > >> > + > >> > + .align 3 > >> > +pe_header: > >> > + .ascii "PE" > >> > + .short 0 > >> > +coff_header: > >> > + .short 0xaa64 /* AArch64 */ > >> > + .short 2 /* nr_sections */ > >> > + .long 0 /* TimeDateStamp > >> */ > >> > + .long 0 /* > >> PointerToSymbolTable */ > >> > + .long 1 /* > >> NumberOfSymbols */ > >> > + .short section_table - optional_header /* > >> SizeOfOptionalHeader */ > >> > + .short 0x206 /* > >> Characteristics. */ > >> > + /* > >> IMAGE_FILE_DEBUG_STRIPPED | */ > >> > + /* > >> IMAGE_FILE_EXECUTABLE_IMAGE | */ > >> > + /* > >> IMAGE_FILE_LINE_NUMS_STRIPPED */ > >> > +optional_header: > >> > + .short 0x20b /* PE32+ format */ > >> > + .byte 0x02 /* > >> MajorLinkerVersion */ > >> > + .byte 0x14 /* > >> MinorLinkerVersion */ > >> > + .long _end - real_start /* SizeOfCode */ > >> > + .long 0 /* > >> SizeOfInitializedData */ > >> > + .long 0 /* > >> SizeOfUninitializedData */ > >> > + .long efi_start - efi_head /* > >> AddressOfEntryPoint */ > >> > + .long real_start - efi_head /* BaseOfCode */ > >> > + > >> > +extra_header_fields: > >> > + .quad 0 /* ImageBase */ > >> > + .long 0x1000 /* > >> SectionAlignment (4 KByte) */ > >> > + .long 0x8 /* FileAlignment > >> */ > >> > + .short 0 /* > >> MajorOperatingSystemVersion */ > >> > + .short 0 /* > >> MinorOperatingSystemVersion */ > >> > + .short 0 /* > >> MajorImageVersion */ > >> > + .short 0 /* > >> MinorImageVersion */ > >> > + .short 0 /* > >> MajorSubsystemVersion */ > >> > + .short 0 /* > >> MinorSubsystemVersion */ > >> > + .long 0 /* > >> Win32VersionValue */ > >> > + > >> > + .long _end - efi_head /* SizeOfImage */ > >> > + > >> > + /* Everything before the kernel image is considered part > >> of the header */ > >> > + .long real_start - efi_head /* SizeOfHeaders > >> */ > >> > + .long 0 /* CheckSum */ > >> > + .short 0xa /* Subsystem (EFI > >> application) */ > >> > + .short 0 /* > >> DllCharacteristics */ > >> > + .quad 0 /* > >> SizeOfStackReserve */ > >> > + .quad 0 /* > >> SizeOfStackCommit */ > >> > + .quad 0 /* > >> SizeOfHeapReserve */ > >> > + .quad 0 /* > >> SizeOfHeapCommit */ > >> > + .long 0 /* LoaderFlags */ > >> > + .long 0x6 /* > >> NumberOfRvaAndSizes */ > >> > + > >> > + .quad 0 /* ExportTable */ > >> > + .quad 0 /* ImportTable */ > >> > + .quad 0 /* ResourceTable > >> */ > >> > + .quad 0 /* ExceptionTable > >> */ > >> > + .quad 0 /* > >> CertificationTable */ > >> > + .quad 0 /* > >> BaseRelocationTable */ > >> > + > >> > + /* Section table */ > >> > +section_table: > >> > > >> > + /* > >> > + * The EFI application loader requires a relocation > >> section > >> > + * because EFI applications must be relocatable. This is > >> a > >> > + * dummy section as far as we are concerned. > >> > + */ > >> > + .ascii ".reloc" > >> > + .byte 0 > >> > + .byte 0 /* end of 0 > >> padding of section name */ > >> > + .long 0 > >> > + .long 0 > >> > + .long 0 /* SizeOfRawData > >> */ > >> > + .long 0 /* > >> PointerToRawData */ > >> > + .long 0 /* > >> PointerToRelocations */ > >> > + .long 0 /* > >> PointerToLineNumbers */ > >> > + .short 0 /* > >> NumberOfRelocations */ > >> > + .short 0 /* > >> NumberOfLineNumbers */ > >> > + .long 0x42100040 /* > >> Characteristics (section flags) */ > >> > + > >> > + > >> > + .ascii ".text" > >> > + .byte 0 > >> > + .byte 0 > >> > + .byte 0 /* end of 0 > >> padding of section name */ > >> > + .long _end - real_start /* VirtualSize */ > >> > + .long real_start - efi_head /* VirtualAddress > >> */ > >> > + .long __init_end_efi - real_start /* SizeOfRawData > >> */ > >> > + .long real_start - efi_head /* > >> PointerToRawData */ > >> > + > >> > + .long 0 /* PointerToRelocations (0 for > >> executables) */ > >> > + .long 0 /* PointerToLineNumbers (0 for > >> executables) */ > >> > + .short 0 /* NumberOfRelocations (0 for > >> executables) */ > >> > + .short 0 /* NumberOfLineNumbers (0 for > >> executables) */ > >> > + .long 0xe0500020 /* Characteristics (section > >> flags) */ > >> > + .align 5 > >> > real_start: > >> > msr DAIFSet, 0xf /* Disable all interrupts */ > >> > > >> > @@ -617,6 +730,37 @@ putn: ret > >> > ENTRY(lookup_processor_type) > >> > mov x0, #0 > >> > ret > >> > +/* > >> > + * Function to transition from EFI loader in C, to Xen entry > >> point. > >> > + * void noreturn efi_xen_start(void *fdt_ptr); > >> > + */ > >> > +ENTRY(efi_xen_start) > >> > + /* > >> > + * Turn off cache and MMU as Xen expects. EFI enables > >> them, but also > >> > + * mandates a 1:1 (unity) VA->PA mapping, so we can turn > >> off the > >> > + * MMU while executing EFI code before entering Xen. > >> > + * The EFI loader calls this to start Xen. > >> > + * Preserve x0 (fdf pointer) across call to > >> __flush_dcache_all, > >> > + * restore for entry into Xen. > >> > + */ > >> > + mov x20, x0 > >> > + bl __flush_dcache_all > >> > + ic ialluis > >> > + > >> > + /* Turn off Dcache and MMU */ > >> > + mrs x0, sctlr_el2 > >> > + bic x0, x0, #1 << 0 /* clear SCTLR.M */ > >> > + bic x0, x0, #1 << 2 /* clear SCTLR.C */ > >> > >> dsb? > >> > >> The dsb is done at the end of __flush_dcache_all > > > > I think this would be to make sure __flush_dcache_all reads the correct > > arguments. We do the same when enabling dcache. > > So where exactly are you suggesting the dsb? Before the call to > __flush_dcache_all? Sorry my comment was wrong, not had my coffee yet! I meant right before: msr sctlr_el2, x0 to make sure that ordering and arguments are correct. And yes, we do the same when enabling dcache see: mrs x0, SCTLR_EL2 orr x0, x0, #SCTLR_M /* Enable MMU */ orr x0, x0, #SCTLR_C /* Enable D-cache */ dsb sy /* Flush PTE writes and finish reads */ msr SCTLR_EL2, x0 /* now paging is enabled */ isb /* Now, flush the icache */ _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
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