df3a109b72
This patch adds a parallel implementation of cbmem that supports dynamic sizing. The original implementation relied on reserving a fixed-size block of memory for adding cbmem entries. In order to allow for more flexibility for adding cbmem allocations the dynamic cbmem infrastructure was developed as an alternative to the fixed block approach. Also, the amount of memory to reserve for cbmem allocations does not need to be known prior to the first allocation. The dynamic cbmem code implements the same API as the existing cbmem code except for cbmem_init() and cbmem_reinit(). The add and find routines behave the same way. The dynamic cbmem infrastructure uses a top down allocator that starts allocating from a board/chipset defined function cbmem_top(). A root pointer lives just below cbmem_top(). In turn that pointer points to the root block which contains the entries for all the large alloctations. The corresponding block for each large allocation falls just below the previous entry. It should be noted that this implementation rounds all allocations up to a 4096 byte granularity. Though a packing allocator could be written for small allocations it was deemed OK to just fragment the memory as there shouldn't be that many small allocations. The result is less code with a tradeoff of some wasted memory. +----------------------+ <- cbmem_top() | +----| root pointer | | | +----------------------+ | | | |--------+ | +--->| root block |-----+ | | +----------------------+ | | | | | | | | | | | | | | alloc N |<----+ | | +----------------------+ | | | | | | | | | \|/ | alloc N + 1 |<-------+ v +----------------------+ In addition to preserving the previous cbmem API, the dynamic cbmem API allows for removing blocks from cbmem. This allows for the boot process to allocate memory that can be discarded after it's been used for performing more complex boot tasks in romstage. In order to plumb this support in there were some issues to work around regarding writing of coreboot tables. There were a few assumptions to how cbmem was layed out which dictated some ifdef guarding and other runtime checks so as not to incorrectly tag the e820 and coreboot memory tables. The example shown below is using dynamic cbmem infrastructure. The reserved memory for cbmem is less than 512KiB. coreboot memory table: 0. 0000000000000000-0000000000000fff: CONFIGURATION TABLES 1. 0000000000001000-000000000002ffff: RAM 2. 0000000000030000-000000000003ffff: RESERVED 3. 0000000000040000-000000000009ffff: RAM 4. 00000000000a0000-00000000000fffff: RESERVED 5. 0000000000100000-0000000000efffff: RAM 6. 0000000000f00000-0000000000ffffff: RESERVED 7. 0000000001000000-000000007bf80fff: RAM 8. 000000007bf81000-000000007bffffff: CONFIGURATION TABLES 9. 000000007c000000-000000007e9fffff: RESERVED 10. 00000000f0000000-00000000f3ffffff: RESERVED 11. 00000000fed10000-00000000fed19fff: RESERVED 12. 00000000fed84000-00000000fed84fff: RESERVED 13. 0000000100000000-00000001005fffff: RAM Wrote coreboot table at: 7bf81000, 0x39c bytes, checksum f5bf coreboot table: 948 bytes. CBMEM ROOT 0. 7bfff000 00001000 MRC DATA 1. 7bffe000 00001000 ROMSTAGE 2. 7bffd000 00001000 TIME STAMP 3. 7bffc000 00001000 ROMSTG STCK 4. 7bff7000 00005000 CONSOLE 5. 7bfe7000 00010000 VBOOT 6. 7bfe6000 00001000 RAMSTAGE 7. 7bf98000 0004e000 GDT 8. 7bf97000 00001000 ACPI 9. 7bf8b000 0000c000 ACPI GNVS 10. 7bf8a000 00001000 SMBIOS 11. 7bf89000 00001000 COREBOOT 12. 7bf81000 00008000 And the corresponding e820 entries: BIOS-e820: [mem 0x0000000000000000-0x0000000000000fff] type 16 BIOS-e820: [mem 0x0000000000001000-0x000000000002ffff] usable BIOS-e820: [mem 0x0000000000030000-0x000000000003ffff] reserved BIOS-e820: [mem 0x0000000000040000-0x000000000009ffff] usable BIOS-e820: [mem 0x00000000000a0000-0x00000000000fffff] reserved BIOS-e820: [mem 0x0000000000100000-0x0000000000efffff] usable BIOS-e820: [mem 0x0000000000f00000-0x0000000000ffffff] reserved BIOS-e820: [mem 0x0000000001000000-0x000000007bf80fff] usable BIOS-e820: [mem 0x000000007bf81000-0x000000007bffffff] type 16 BIOS-e820: [mem 0x000000007c000000-0x000000007e9fffff] reserved BIOS-e820: [mem 0x00000000f0000000-0x00000000f3ffffff] reserved BIOS-e820: [mem 0x00000000fed10000-0x00000000fed19fff] reserved BIOS-e820: [mem 0x00000000fed84000-0x00000000fed84fff] reserved BIOS-e820: [mem 0x0000000100000000-0x00000001005fffff] usable Change-Id: Ie3bca52211800a8652a77ca684140cfc9b3b9a6b Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/2848 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com> |
||
---|---|---|
3rdparty@ba8caa30bd | ||
documentation | ||
payloads | ||
src | ||
util | ||
.gitignore | ||
.gitmodules | ||
.gitreview | ||
COPYING | ||
Makefile | ||
Makefile.inc | ||
README |
README
------------------------------------------------------------------------------- coreboot README ------------------------------------------------------------------------------- coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload. With the separation of hardware initialization and later boot logic, coreboot can scale from specialized applications that run directly firmware, run operating systems in flash, load custom bootloaders, or implement firmware standards, like PC BIOS services or UEFI. This allows for systems to only include the features necessary in the target application, reducing the amount of code and flash space required. coreboot was formerly known as LinuxBIOS. Payloads -------- After the basic initialization of the hardware has been performed, any desired "payload" can be started by coreboot. See http://www.coreboot.org/Payloads for a list of supported payloads. Supported Hardware ------------------ coreboot supports a wide range of chipsets, devices, and mainboards. For details please consult: * http://www.coreboot.org/Supported_Motherboards * http://www.coreboot.org/Supported_Chipsets_and_Devices Build Requirements ------------------ * gcc / g++ * make Optional: * doxygen (for generating/viewing documentation) * iasl (for targets with ACPI support) * gdb (for better debugging facilities on some targets) * ncurses (for 'make menuconfig') * flex and bison (for regenerating parsers) Building coreboot ----------------- Please consult http://www.coreboot.org/Build_HOWTO for details. Testing coreboot Without Modifying Your Hardware ------------------------------------------------ If you want to test coreboot without any risks before you really decide to use it on your hardware, you can use the QEMU system emulator to run coreboot virtually in QEMU. Please see http://www.coreboot.org/QEMU for details. Website and Mailing List ------------------------ Further details on the project, a FAQ, many HOWTOs, news, development guidelines and more can be found on the coreboot website: http://www.coreboot.org You can contact us directly on the coreboot mailing list: http://www.coreboot.org/Mailinglist Copyright and License --------------------- The copyright on coreboot is owned by quite a large number of individual developers and companies. Please check the individual source files for details. coreboot is licensed under the terms of the GNU General Public License (GPL). Some files are licensed under the "GPL (version 2, or any later version)", and some files are licensed under the "GPL, version 2". For some parts, which were derived from other projects, other (GPL-compatible) licenses may apply. Please check the individual source files for details. This makes the resulting coreboot images licensed under the GPL, version 2.