aboutsummaryrefslogtreecommitdiffstats
path: root/src/arch/x86/prefix
Commit message (Collapse)AuthorAgeFilesLines
* [build] Fix building with newer binutilsMichael Brown2024-01-1414-12/+14
| | | | | | | | | | | | | | | | | Newer versions of the GNU assembler (observed with binutils 2.41) will complain about the ".arch i386" in files assembled with "as --64", with the message "Error: 64bit mode not supported on 'i386'". In files such as stack.S that contain no instructions to be assembled, the ".arch i386" is redundant and may be removed entirely. In the remaining files, fix by moving ".arch i386" below the relevant ".code16" or ".code32" directive, so that the assembler is no longer expecting 64-bit instructions to be used by the time that the ".arch i386" directive is encountered. Reported-by: Ali Mustakim <alim@forwardcomputers.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Remove unnecessary ".text" directivesMichael Brown2024-01-1415-15/+0
| | | | | | | | | The .text directive is entirely redundant when followed by a .section directive giving an explicit section name and attributes. Remove these unnecessary directives to simplify the code. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Inhibit linker warnings about an implied executable stackGeert Stappers2023-06-3016-0/+16
| | | | | | Signed-off-by: Geert Stappers <stappers@stappers.it> Modified-by: Michael Brown <mcb30@ipxe.org> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Fix use of writable code segment on 486 and earlier CPUsfix486Michael Brown2022-02-021-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In real mode, code segments are always writable. In protected mode, code segments can never be writable. The precise implementation of this attribute differs between CPU generations, with subtly different behaviour arising on the transitions from protected mode to real mode. At the point of transition (when the PE bit is cleared in CR0) the hidden portion of the %cs descriptor will retain whatever attributes were in place for the protected-mode code segment, including the fact that the segment is not writable. The immediately following code will perform a far control flow transfer (such as ljmp or lret) in order to load a real-mode value into %cs. On the Pentium and later CPUs, the retained protected-mode attributes will be ignored for any accesses via %cs while the CPU is in real mode. A write via %cs will therefore be allowed even though the hidden portion of the %cs descriptor still describes a non-writable segment. On the 486 and earlier CPUs, the retained protected-mode attributes will not be ignored for accesses via %cs. A write via %cs will therefore cause a CPU fault. To obtain normal real-mode behaviour (i.e. a writable %cs descriptor), special logic is added to the ljmp instruction that populates the hidden portion of the %cs descriptor with real-mode attributes when a far jump is executed in real mode. The result is that writes via %cs will cause a CPU fault until the first ljmp instruction is executed, after which writes via %cs will be allowed as expected in real mode. The transition code in libprefix.S currently uses lret to load a real-mode value into %cs after clearing the PE bit. Experimentation shows that only the ljmp instruction will work to load real-mode attributes into the hidden portion of the %cs descriptor: other far control flow transfers (such as lret, lcall, or int) do not do so. When running on a 486 or earlier CPU, this results in code within libprefix.S running with a non-writable code segment after a mode transition, which in turn results in a CPU fault when real-mode code in liba20.S attempts to write to %cs:enable_a20_method. Fix by constructing and executing an ljmp instruction, to trigger the relevant descriptor population logic on 486 and earlier CPUs. This ljmp instruction is constructed on the stack, since the .prefix section may be executing directly from ROM (or from memory that the BIOS has write-protected in order to emulate an ISA ROM region) and so cannot be modified. Reported-by: Nikolai Zhubr <n-a-zhubr@yandex.ru> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [doc] Update user-visible ipxe.org URIs to use HTTPSMichael Brown2022-01-131-2/+2
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Specify i486 architecture for LZMA decompressorMichael Brown2021-05-121-1/+1
| | | | | | | | | | The decompressor uses the i486 "bswap" instruction, but does not require any instructions that exist only on i586 or above. Update the ".arch" directive to reflect the requirements of the code as implemented. Reported-by: Martin Habets <habetsm.xilinx@gmail.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Add a generic raw image prefixMichael Brown2021-02-181-0/+53
| | | | | | | | | | | | | | | | | | | | Provide a generic raw image prefix, which assumes that the iPXE image has been loaded in its entirety on a paragraph boundary. The resulting .raw image can be loaded via RPL using an rpld.conf file such as: HOST { ethernet = 00:00:00:00:00:00/6; FILE { path="ipxe.raw"; load=0x2000; }; execute=0x2000; }; Debugged-by: Johannes Heimansberg <git@jhe.dedyn.io> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Use .balign directive instead of .alignMichael Brown2021-02-124-7/+7
| | | | | | | | | | | | | The semantics of the assembler's .align directive vary by CPU architecture. For the ARM builds, it specifies a power of two rather than a number of bytes. This currently leads to the .einfo entries (which do not appear in the final binary) having an alignment of 256 bytes for the ARM builds. Fix by switching to the GNU-specific directive .balign, which is consistent across architectures Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [int13con] Create log partition only when CONSOLE_INT13 is enabledMichael Brown2020-03-011-0/+17
| | | | | | | | Reduce the size of the USB disk image in the common case that CONSOLE_INT13 is not enabled. Originally-implemented-by: Romain Guyard <romain.guyard@mujin.co.jp> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [bios] Define macros for constructing partition table entriesMichael Brown2020-03-011-10/+37
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [pci] Correct invalid base-class/sub-class/prog-if order in PCIRPetr Borsodi2019-01-152-2/+2
| | | | | | | | | PCI Configuration Space contains fields prog-if at the offset 0x09, sub-class at the offset 0x0a and base-class at the offset 0x0b (it respects little endian). PCIR structure uses these fields in the same order. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Avoid use of "ld --oformat binary"Michael Brown2018-01-021-0/+1
| | | | | | | | | | | | | | | | Using "ld --oformat binary" for mbr.bin and usbdisk.bin seems to cause segmentation faults on some versions of binutils (observed on Fedora 27). Work around this problem by using ld to create an intermediate ELF object, followed by objcopy (via the existing %.tmp -> %.bin rule) to create the final binary. Note that we cannot simply use a single-stage "objcopy -O binary" since this will not process the relocation records for x86_64: see commit 1afcccd ("[build] Do not use "objcopy -O binary" for objects with relocation records"). Reported-by: Brent S <bts@square-r00t.net> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [romprefix] Avoid unaligned accesses within ROM headersMichael Brown2017-08-302-0/+4
| | | | | | | | | Ensure that all headers (PCI, UNDI, PnP, iPXE) are aligned to at least four bytes, so that all accesses to header fields will be correctly aligned even when reading directly from the expansion ROM BAR. Reported-by: Peter von Konigsmark <peter@exablaze.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [hdprefix] Avoid attempts to read beyond the end of the diskMichael Brown2017-06-141-5/+9
| | | | | | | | | When booting from a hard disk image (e.g. bin/ipxe.usb) within an emulator such as QEMU, the disk may not exist beyond the end of the image. Limit all reads to the length of the image to avoid spurious errors when loading the iPXE image. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Include diagnostic information within progress messagesMichael Brown2016-12-061-14/+38
| | | | | | | Include some relevant diagnostic infomation within the progress messages generated via DEBUG=libprefix. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Remove impossible progress messageMichael Brown2016-12-061-1/+0
| | | | | | | | | | | | | | | | | | | | The "progress" macro can be used only from within the .prefix section. At the point of calling relocate(), we are running in .text16 and so the near call to print_message() will end up calling a random function somewhere in .text16. Interestingly, this problem has remained unnoticed for some time. It is rare to build with DEBUG=libprefix. In the few cases that it has been used during development, the randomly selected function in .text16 seems to have been a harmless no-op with no visible side-effects (beyond the unnoticed failure to print the "relocate" progress message). Fix by removing the futile attempt to print a progress message before calling relocate(). Reported-by: Raed Salem <raeds@mellanox.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [romprefix] Avoid using PMM-allocated memory in UNDI loader entry pointMichael Brown2016-12-052-1/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The UNDI loader entry point is very likely to be called after POST, when there is a high chance that the PMM-allocated image source area and decompression area have been reused by something else. In particular, using an iPXE .iso to test a separate iPXE ROM's UNDI loader entry point in a qemu VM is likely to crash. SeaBIOS allocates PMM blocks from close to the top of memory and so these blocks have a high chance of colliding with the runtime addresses subsequently chosen by the non-ROM iPXE by scanning the INT 15,e820 memory map. The standard romprefix.S has no choice about relying on the PMM-allocated image source area, since it has no other way to retrieve its compressed payload. In mromprefix.S, the image source area functions only as an optional buffer used to avoid repeated reads from the (potentially slow) expansion ROM BAR by the decompression code. We can therefore always set %esi=0 when calling install_prealloc from the UNDI loader entry point, and simply fall back to reading directly from the expansion ROM BAR. We can always set %edi=0 when calling install_prealloc from the UNDI loader entry point. This will behave as though the decompression area PMM allocation failed, and will therefore use INT 15,88 to find a temporary decompression area somewhere close to 64MB. This is by no means guaranteed to be safe from collisions, but it's probably safer on balance than the PMM-allocated address. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Use CRC32 to verify each block prior to decompressionMichael Brown2016-03-242-35/+118
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Move architecture-independent EFI prefixes to interface/efiMichael Brown2016-03-172-182/+0
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [librm] Provide an abstraction wrapper for prot_callMichael Brown2016-02-189-19/+29
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [librm] Convert prot_call() to a real-mode near callMichael Brown2016-02-189-9/+0
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Standardise calls to prot_call()Michael Brown2016-02-182-11/+28
| | | | | | | Use the standard "pushl $function ; pushw %cs ; call prot_call" sequence everywhere that prot_call() is used. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Use garbage-collectable section namesMichael Brown2016-02-181-20/+20
| | | | | | Allow unused sections of libprefix.o to be removed via --gc-sections. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [romprefix] Align PMM temporary decompression area to a page boundaryMichael Brown2016-02-181-6/+9
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [prefix] Align INT 15,88 temporary decompression area to a page boundaryMichael Brown2016-02-181-0/+1
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [librm] Discard argument as part of return from prot_call()Michael Brown2016-02-169-11/+1
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [bios] Add bin-x86_64-pcbios build platformMichael Brown2016-02-1621-0/+5656
| | | | | | | | | | | | | | Move most arch/i386 files to arch/x86, and adjust the contents of the Makefiles and the include/bits/*.h headers to reflect the new locations. This patch makes no substantive code changes, as can be seen using a rename-aware diff (e.g. "git show -M5"). This patch does not make the pcbios platform functional for x86_64; it merely allows it to compile without errors. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Hold off watchdog timer while runningMichael Brown2015-08-031-0/+5
| | | | | | | | | | | | | | | | UEFI platforms may provide a watchdog timer, which will reboot the machine if an operating system takes more than five minutes to load. This can cause long-lived iPXE downloads (or interactive shell sessions) to unexpectedly reboot. Fix by resetting the watchdog timer every ten seconds while the iPXE main processing loop continues to run. Reported-by: Bradley B Williams <bradleybwilliams@swbell.net> Reported-by: John Clark <john.r.clark.3@gmail.com> Reported-by: wdriever@gmail.com Reported-by: Charlie Beima <cbeima@indiana.edu> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Ensure drivers are disconnected when ExitBootServices() is calledMichael Brown2015-04-131-0/+35
| | | | | | | | | | | | | | | | | | We hook the UEFI ExitBootServices() event and use it to trigger a call to shutdown_boot(). This does not automatically cause drivers to be disconnected from their devices, since device enumeration is now handled by the UEFI core rather than by iPXE. (Under the old and dubiously compatible device model, iPXE used to perform its own device enumeration and so the call to shutdown_boot() would indeed have caused drivers to be disconnected.) Fix by replicating parts of the dummy "EFI root device" from efiprefix.c to efidrvprefix.c, so that the call to shutdown_boot() will call efi_driver_disconnect_all(). Originally-fixed-by: Laszlo Ersek <lersek@redhat.com> Tested-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Default to releasing network devices for use via SNPMichael Brown2014-07-302-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | We currently treat network devices as available for use via the SNP API only if RX queue processing has been frozen. (This is similar in spirit to the way that RX queue processing is frozen for the network device currently exposed via the PXE API.) The default state of a freshly created network device is for the RX queue to not be frozen, and thus to be unavailable for use via SNP. This causes problems when devices are added through code paths other than _efidrv_start() (which explicitly releases devices for use via SNP). We don't actually need to freeze RX queue processing, since calls via the SNP API will always use netdev_poll() rather than net_poll(), and so will never trigger the RX queue processing code path anyway. We can therefore simplify the code to use a single global flag to indicate whether network devices are claimed for use by iPXE or available for use via SNP. Using a global flag allows the default state for dynamically created network devices to behave sensibly. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Identify autoboot device by MAC address when chainloadingMichael Brown2014-07-081-0/+4
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Restructure EFI driver modelMichael Brown2014-06-251-0/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a single instance of EFI_DRIVER_BINDING_PROTOCOL (attached to our image handle); this matches the expectations scattered throughout the EFI specification. Open the underlying hardware device using EFI_OPEN_PROTOCOL_BY_DRIVER and EFI_OPEN_PROTOCOL_EXCLUSIVE, to prevent other drivers from attaching to the same device. Do not automatically connect to devices when being loaded as a driver; leave this task to the platform firmware (or to the user, if loading directly from the EFI shell). When running as an application, forcibly disconnect any existing drivers from devices that we want to control, and reconnect them on exit. Provide a meaningful driver version number (based on the build timestamp), to allow platform firmware to automatically load newer versions of iPXE drivers if multiple drivers are present. Include device paths within debug messages where possible, to aid in debugging. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Disable SNP devices when running iPXE as the applicationMichael Brown2014-03-141-2/+4
| | | | | | | | | | | | | Some UEFI builds will set up a timer to continuously poll any SNP devices. This can drain packets from the network device's receive queue before iPXE gets a chance to process them. Use netdev_rx_[un]freeze() to explicitly indicate when we expect our network devices to be driven via the external SNP API (as we do with the UNDI API on the standard BIOS build), and disable the SNP API except when receive queue processing is frozen. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Unload our own image before exiting UEFI applicationMichael Brown2014-03-141-4/+9
| | | | Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Avoid accidentally calling main() twiceMichael Brown2014-03-141-1/+5
| | | | | | | | | | | | | | EFIRC() uses PLATFORM_TO_ERRNO(), which evaluates its argument twice (and can't trivially use a braced-group expression or an inline function to avoid this, since it gets used outside of function context). The expression "EFIRC(main())" will therefore end up calling main() twice, which is not the intended behaviour. Every other instance of EFIRC() is of the simple form "EFIRC(rc)", so fix by converting this instance to match. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Perform meaningful error code conversionsMichael Brown2013-04-191-1/+2
| | | | | | | | Exploit the redefinition of iPXE error codes to include a "platform error code" to allow for meaningful conversion of EFI_STATUS values to iPXE errors and vice versa. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [legal] Update FSF mailing address in GPL licence textsMichael Brown2012-07-202-2/+4
| | | | | Suggested-by: Daniel P. Berrange <berrange@redhat.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Allow EFI to control PCI bus enumerationMichael Brown2011-02-171-2/+3
| | | | | | | | | | | | | | EFI performs its own PCI bus enumeration. Respect this, and start controlling devices only when instructed to do so by EFI. As a side benefit, we should now correctly create multiple SNP instances for multi-port devices. This should also fix the problem of failing to enumerate devices because the PCI bridges have not yet been enabled at the time the iPXE driver is loaded. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [efi] Fix .efi and .efidrv linkingPiotr Jaroszyński2010-05-272-4/+4
| | | | | | | | | | | | | | The linker chooses to look for _start first and always picks efidrvprefix.o to satisfy it (probably because it's earlier in the archive) which causes a multiple definition error when the linker later has to pick efiprefix.o for other symbols. Fix by using EFI-specific TGT_LD_FLAGS with an explicit entry point. Signed-off-by: Piotr Jaroszyński <p.jaroszynski@gmail.com> Signed-off-by: Joshua Oreman <oremanj@rwcr.net> Modified-by: Michael Brown <mcb30@ipxe.org> Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [build] Rename gPXE to iPXEMichael Brown2010-04-192-4/+4
| | | | | | | | | | | Access to the gpxe.org and etherboot.org domains and associated resources has been revoked by the registrant of the domain. Work around this problem by renaming project from gPXE to iPXE, and updating URLs to match. Also update README, LOG and COPYRIGHTS to remove obsolete information. Signed-off-by: Michael Brown <mcb30@ipxe.org>
* [legal] Add a selection of FILE_LICENCE declarationsMichael Brown2009-05-182-0/+4
| | | | | Add FILE_LICENCE declarations to almost all files that make up the various standard builds of gPXE.
* [efi] Allow for .efidrv images as well as .efi imagesMichael Brown2009-01-071-0/+44
| | | | | | Merge in the changes that allow for building EFI driver images (that can be loaded using the EFI shell's "load" command) as well as EFI applications.
* [efi] Use elf2efi utility in place of efilinkMichael Brown2009-01-071-0/+39
elf2efi converts a suitable ELF executable (containing relocation information, and with appropriate virtual addresses) into an EFI executable. It is less tightly coupled with the gPXE build process and, in particular, does not require the use of a hand-crafted PE image header in efiprefix.S. elf2efi correctly handles .bss sections, which significantly reduces the size of the gPXE EFI executable.
generated by cgit (git 2.34.1) at 2025-02-23 22:13:28 +0000