1.. SPDX-License-Identifier: GPL-2.0+
2.. sectionauthor:: Aiden Park <aiden.park@intel.com>
3
4Slim Bootloader
5===============
6
7Introduction
8------------
9
10This target is to enable U-Boot_ as a payload of `Slim Bootloader`_ (a.k.a SBL)
11boot firmware which currently supports QEMU, Apollolake, Whiskeylake,
12Coffeelake-R platforms.
13
14The `Slim Bootloader`_ is designed with multi-stages (Stage1A/B, Stage2, Payload)
15architecture to cover from reset vector to OS booting and it consumes
16`Intel FSP`_ for silicon initialization.
17
18* Stage1A: Reset vector, CAR init with FSP-T
19* Stage1B: Memory init with FSP-M, CAR teardown, Continue execution in memory
20* Stage2 : Rest of Silicon init with FSP-S, Create HOB, Hand-off to Payload
21* Payload: Payload init with HOB, Load OS from media, Booting OS
22
23The Slim Bootloader stages (Stage1A/B, Stage2) focus on chipset, hardware and
24platform specific initialization, and it provides useful information to a
25payload in a HOB (Hand-Off Block) which has serial port, memory map, performance
26data info and so on. This is Slim Bootloader architectural design to make a
27payload light-weight, platform independent and more generic across different
28boot solutions or payloads, and to minimize hardware re-initialization in a
29payload.
30
31Build Instruction for U-Boot as a Slim Bootloader payload
32---------------------------------------------------------
33
34Build U-Boot and obtain u-boot-dtb.bin::
35
36   $ make distclean
37   $ make slimbootloader_defconfig
38   $ make all
39
40Prepare Slim Bootloader
41-----------------------
42
431. Setup Build Environment for Slim Bootloader.
44
45   Refer to `Getting Started`_ page in `Slim Bootloader`_ document site.
46
472. Get source code. Let's simply clone the repo::
48
49   $ git clone https://github.com/slimbootloader/slimbootloader.git
50
513. Copy u-boot-dtb.bin to Slim Bootloader.
52   Slim Bootloader looks for a payload from the specific location.
53   Copy the build u-boot-dtb.bin to the expected location::
54
55   $ mkdir -p <Slim Bootloader Dir>/PayloadPkg/PayloadBins/
56   $ cp <U-Boot Dir>/u-boot-dtb.bin <Slim Bootloader Dir>/PayloadPkg/PayloadBins/u-boot-dtb.bin
57
58Build Instruction for Slim Bootloader for QEMU target
59-----------------------------------------------------
60
61Slim Bootloader supports multiple payloads, and a board of Slim Bootloader
62detects its target payload by PayloadId in board configuration.
63The PayloadId can be any 4 Bytes value.
64
651. Update PayloadId. Let's use 'U-BT' as an example::
66
67    $ vi Platform/QemuBoardPkg/CfgData/CfgDataExt_Brd1.dlt
68    -GEN_CFG_DATA.PayloadId                     | 'AUTO'
69    +GEN_CFG_DATA.PayloadId                     | 'U-BT'
70
712. Update payload text base. PAYLOAD_EXE_BASE must be the same as U-Boot
72   CONFIG_SYS_TEXT_BASE in board/intel/slimbootloader/Kconfig.
73   PAYLOAD_LOAD_HIGH must be 0::
74
75    $ vi Platform/QemuBoardPkg/BoardConfig.py
76    +               self.PAYLOAD_LOAD_HIGH    = 0
77    +               self.PAYLOAD_EXE_BASE     = 0x00100000
78
793. Build QEMU target. Make sure u-boot-dtb.bin and U-BT PayloadId
80   in build command. The output is Outputs/qemu/SlimBootloader.bin::
81
82   $ python BuildLoader.py build qemu -p "OsLoader.efi:LLDR:Lz4;u-boot-dtb.bin:U-BT:Lzma"
83
844. Launch Slim Bootloader on QEMU.
85   You should reach at U-Boot serial console::
86
87   $ qemu-system-x86_64 -machine q35 -nographic -serial mon:stdio -pflash Outputs/qemu/SlimBootloader.bin
88
89Test Linux booting on QEMU target
90---------------------------------
91
92Let's use LeafHill (APL) Yocto image for testing.
93Download it from http://downloads.yoctoproject.org/releases/yocto/yocto-2.0/machines/leafhill/.
94
951. Prepare Yocto hard disk image::
96
97   $ wget http://downloads.yoctoproject.org/releases/yocto/yocto-2.0/machines/leafhill/leafhill-4.0-jethro-2.0.tar.bz2
98   $ tar -xvf leafhill-4.0-jethro-2.0.tar.bz2
99   $ ls -l leafhill-4.0-jethro-2.0/binary/core-image-sato-intel-corei7-64.hddimg
100
1012. Launch Slim Bootloader on QEMU with disk image::
102
103   $ qemu-system-x86_64 -machine q35 -nographic -serial mon:stdio -pflash Outputs/qemu/SlimBootloader.bin -drive id=mydrive,if=none,file=/path/to/core-image-sato-intel-corei7-64.hddimg,format=raw -device ide-hd,drive=mydrive
104
1053. Update boot environment values on shell::
106
107   => setenv bootfile vmlinuz
108   => setenv bootdev scsi
109   => boot
110
111Build Instruction for Slim Bootloader for LeafHill (APL) target
112---------------------------------------------------------------
113
114Prepare U-Boot and Slim Bootloader as described at the beginning of this page.
115Also, the PayloadId needs to be set for APL board.
116
1171. Update PayloadId. Let's use 'U-BT' as an example::
118
119    $ vi Platform/ApollolakeBoardPkg/CfgData/CfgData_Int_LeafHill.dlt
120    -GEN_CFG_DATA.PayloadId                     | 'AUTO
121    +GEN_CFG_DATA.PayloadId                     | 'U-BT'
122
1232. Update payload text base.
124
125* PAYLOAD_EXE_BASE must be the same as U-Boot CONFIG_SYS_TEXT_BASE
126  in board/intel/slimbootloader/Kconfig.
127* PAYLOAD_LOAD_HIGH must be 0::
128
129    $ vi Platform/ApollolakeBoardPkg/BoardConfig.py
130    +               self.PAYLOAD_LOAD_HIGH    = 0
131    +               self.PAYLOAD_EXE_BASE     = 0x00100000
132
1333. Build APL target. Make sure u-boot-dtb.bin and U-BT PayloadId
134   in build command. The output is Outputs/apl/Stitch_Components.zip::
135
136   $ python BuildLoader.py build apl -p "OsLoader.efi:LLDR:Lz4;u-boot-dtb.bin:U-BT:Lzma"
137
1384. Stitch IFWI.
139
140   Refer to Apollolake_ page in Slim Bootloader document site::
141
142   $ python Platform/ApollolakeBoardPkg/Script/StitchLoader.py -i <Existing IFWI> -s Outputs/apl/Stitch_Components.zip -o <Output IFWI>
143
1445. Flash IFWI.
145
146   Use DediProg to flash IFWI. You should reach at U-Boot serial console.
147
148
149Build Instruction to use ELF U-Boot
150-----------------------------------
151
1521. Enable CONFIG_OF_EMBED::
153
154    $ vi configs/slimbootloader_defconfig
155    +CONFIG_OF_EMBED=y
156
1572. Build U-Boot::
158
159   $ make distclean
160   $ make slimbootloader_defconfig
161   $ make all
162   $ strip u-boot (removing symbol for reduced size)
163
1643. Do same steps as above
165
166* Copy u-boot (ELF) to PayloadBins directory
167* Update PayloadId 'U-BT' as above.
168* No need to set PAYLOAD_LOAD_HIGH and PAYLOAD_EXE_BASE.
169* Build Slim Bootloader. Use u-boot instead of u-boot-dtb.bin::
170
171   $ python BuildLoader.py build <qemu or apl> -p "OsLoader.efi:LLDR:Lz4;u-boot:U-BT:Lzma"
172
173.. _U-Boot: https://source.denx.de/
174.. _`Slim Bootloader`: https://github.com/slimbootloader/
175.. _`Intel FSP`: https://github.com/IntelFsp/
176.. _`Getting Started`: https://slimbootloader.github.io/getting-started/
177.. _Apollolake: https://slimbootloader.github.io/supported-hardware/apollo-lake-crb.html#stitching
178