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Diffstat (limited to 'Documentation')
3 files changed, 163 insertions, 4 deletions
diff --git a/Documentation/mainboard/lenovo/Sandy_Bridge_series.md b/Documentation/mainboard/lenovo/Sandy_Bridge_series.md index 0b833f5cc8..dbbbbeef30 100644 --- a/Documentation/mainboard/lenovo/Sandy_Bridge_series.md +++ b/Documentation/mainboard/lenovo/Sandy_Bridge_series.md @@ -33,9 +33,7 @@ usable by coreboot. * ROM chip size should be set to 8MiB. -```eval_rst -Please also have a look at :doc:`../../flash_tutorial/index`. -``` +Please also have a look at the [flashing tutorial] ## Flash layout There's one 8MiB flash which contains IFD, GBE, ME and BIOS regions. @@ -46,3 +44,26 @@ region. The update is then written into the EC once. [fl]: flashlayout_Sandy_Bridge.svg +## Reducing Intel Managment Engine firmware size + +It is possible to reduce the Intel ME firmware size to free additional +space for the `bios` region. This is usually refered to as *cleaning the ME* or +*stripping the ME*. +After reducing the Intel ME firmware size you must modify the original IFD +and then write a full ROM using an [external programmer]. +Have a look at the [me_cleaner] for more information. + +Tests on Lenovo X220 showed no issues with a stripped ME firmware. + +**Modified flash layout:** + +![][fl2] + +[fl2]: flashlayout_Sandy_Bridge_stripped_me.svg + +The overall size of the `gbe`, `me,` `ifd` region is less than 128KiB, leaving +the remaining space for the `bios` partition. + + +[me_cleaner]: ../../northbridge/intel/sandybridge/me_cleaner.md +[external programmer]: ../../flash_tutorial/index.md diff --git a/Documentation/mainboard/lenovo/flashlayout_Sandy_Bridge_stripped_me.svg b/Documentation/mainboard/lenovo/flashlayout_Sandy_Bridge_stripped_me.svg new file mode 100644 index 0000000000..d8d8213d12 --- /dev/null +++ b/Documentation/mainboard/lenovo/flashlayout_Sandy_Bridge_stripped_me.svg @@ -0,0 +1,74 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.0//EN" "http://www.w3.org/TR/2001/PR-SVG-20010719/DTD/svg10.dtd"> +<svg width="9cm" height="8cm" viewBox="268 -156 168 158" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"> + <g> + <g> + <g> + <rect style="fill: #ffffff" x="307.888" y="-152.131" width="49.1438" height="30.4667"/> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #ffffff" x="307.888" y="-152.131" width="49.1438" height="30.4667"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #ffffff" x="307.888" y="-152.131" width="49.1438" height="30.4667"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #000000" x="307.888" y="-152.131" width="49.1438" height="30.4667"/> + <text font-size="6.77323" style="fill: #000000;text-anchor:middle;font-family:sans-serif;font-style:normal;font-weight:normal" x="332.46" y="-134.831"> + <tspan x="332.46" y="-134.831">IFD</tspan> + </text> + </g> + <g> + <g> + <rect style="fill: #ffffff" x="307.934" y="-56.9106" width="49.1438" height="56.1492"/> + <rect style="fill: none; fill-opacity:0; stroke-width: 0.02; stroke: #ffffff" x="307.934" y="-56.9106" width="49.1438" height="56.1492"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 0.02; stroke: #ffffff" x="307.934" y="-56.9106" width="49.1438" height="56.1492"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #000000" x="308.096" y="-57.559" width="49.1438" height="57.2839"/> + <text font-size="6.77323" style="fill: #000000;text-anchor:middle;font-family:sans-serif;font-style:normal;font-weight:normal" x="332.182" y="-24.0245"> + <tspan x="332.182" y="-24.0245">BIOS</tspan> + </text> + <g> + <g> + <g> + <rect style="fill: #ffffff" x="308" y="-121.59" width="49.1438" height="30.4667"/> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #ffffff" x="308" y="-121.59" width="49.1438" height="30.4667"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #ffffff" x="308" y="-121.59" width="49.1438" height="30.4667"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #000000" x="308" y="-121.59" width="49.1438" height="30.4667"/> + <text font-size="6.77323" style="fill: #000000;text-anchor:middle;font-family:sans-serif;font-style:normal;font-weight:normal" x="332.572" y="-104.29"> + <tspan x="332.572" y="-104.29">GBE</tspan> + </text> + </g> + <text font-size="7.15705" style="fill: #000000;text-anchor:start;font-family:sans-serif;font-style:normal;font-weight:normal" x="268.961" y="-148.674"> + <tspan x="268.961" y="-148.674">0x000000</tspan> + </text> + <text font-size="6.77323" style="fill: #000000;text-anchor:start;font-family:sans-serif;font-style:normal;font-weight:normal" x="269.152" y="-120.399"> + <tspan x="269.152" y="-120.399">0x001000</tspan> + </text> + <text font-size="6.77323" style="fill: #000000;text-anchor:start;font-family:sans-serif;font-style:normal;font-weight:normal" x="269.155" y="-90.6472"> + <tspan x="269.155" y="-90.6472">0x003000</tspan> + </text> + <text font-size="6.77323" style="fill: #000000;text-anchor:start;font-family:sans-serif;font-style:normal;font-weight:normal" x="269.461" y="-56.4289"> + <tspan x="269.461" y="-56.4289">0x020000</tspan> + </text> + <text font-size="6.77323" style="fill: #000000;text-anchor:start;font-family:sans-serif;font-style:normal;font-weight:normal" x="270.008" y="0.198407"> + <tspan x="270.008" y="0.198407">0x800000</tspan> + </text> + <path style="fill: none; fill-opacity:0; stroke-width: 1; stroke: #000000" d="M 380.877 -151.013 C 401.876,-151.013 379.377,-73.513 400.627,-72.513"/> + <path style="fill: none; fill-opacity:0; stroke-width: 1; stroke: #000000" d="M 381.377 -0.763268 C 395.238,-0.763268 387.016,-72.763 400.877,-72.763"/> + <text font-size="6.77323" style="fill: #000000;text-anchor:start;font-family:sans-serif;font-style:normal;font-weight:normal" x="406.127" y="-68.513"> + <tspan x="406.127" y="-68.513">Flash #0</tspan> + </text> + <g> + <g> + <g> + <rect style="fill: #ffffff" x="308.189" y="-90.5898" width="49.1438" height="33.4161"/> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #ffffff" x="308.189" y="-90.5898" width="49.1438" height="33.4161"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #ffffff" x="308.189" y="-90.5898" width="49.1438" height="33.4161"/> + </g> + <rect style="fill: none; fill-opacity:0; stroke-width: 2; stroke: #000000" x="308.189" y="-90.5898" width="49.1438" height="32.8215"/> + <text font-size="6.77323" style="fill: #000000;text-anchor:middle;font-family:sans-serif;font-style:normal;font-weight:normal" x="331.572" y="-70.23"> + <tspan x="331.572" y="-70.23">ME</tspan> + </text> + </g> +</svg> diff --git a/Documentation/northbridge/intel/sandybridge/me_cleaner.md b/Documentation/northbridge/intel/sandybridge/me_cleaner.md index 1086e7e091..b457dcdd3c 100644 --- a/Documentation/northbridge/intel/sandybridge/me_cleaner.md +++ b/Documentation/northbridge/intel/sandybridge/me_cleaner.md @@ -5,7 +5,7 @@ from the ME firmware partition. In this state the ME errors out and doesn't operate any more. **Using a 'cleaned' ME partition may lead to issues and its use should be -carefully evaulated.** +carefully evaluated.** ## Observations with 'cleaned' ME @@ -18,3 +18,67 @@ carefully evaulated.** Always test with unmodified IFD and ME section before reporting bugs to the coreboot project. + +## Tutorial reducing the Intel ME firmware size + +By default the cleaned ME firmware will still occupy the same space in +the firmware image. It's possible to change the firmware partition layout +and reclaim the space for the use by coreboot. +With the reduced Intel ME firmware the `ifd`, `gbe` and `me` regions require +less than 128 KiB of space in the ROM, which leaves the remaining for the +`bios` region. + +This tutorial will guide you through the steps necessary. + +### 1. Obtain a full ROM + +You need a full and working ROM with a full Intel ME firmware. + +### 2. Running me_cleaner + +You need to run the *me_cleaner* on a full ROM, here called `fulldump.rom`: +The full ROM contains: +* IFD +* fully working Intel ME +* GbE (optional) +* BIOS (any firmware) + +Running the command will generate two new files: +```console +./util/me_cleaner/me_cleaner.py -D patched_desciptor.bin -M stripped_me.bin fulldump.rom -t -r -S +``` + +The generated files are: +* a patched IFD called `patched_desciptor.bin` +* stripped Intel ME called `stripped_me.bin` + +The patched IFD has the *AltMeDisable* bit set and a modified flash layout. + + +*Note:* coreboot allows to select `CONFIG_ME_CLEANER` as part of the +build-process, but that doesn't rework the flash layout, it only removes +files from ME and sets the *AltMeDisable*-bit. + +### 3. Build coreboot + +1. Now include the two new files from the previous step into coreboot's + build system. +2. Make sure to also increase the CBFS size + * 0x7E0000 for a 8MiB ROM + * 0xBE0000 for a 12MiB ROM + * 0xFE0000 for a 16MiB ROM +3. Make sure to **not** enable me_cleaner in Kconfig again as + you have already run it + +### 4. Flashing the ROM + +As you have modified the layout you need to write the **full ROM** to flash +using an [external programmer]. +Make sure to include all partitions into the ROM: +* IFD +* EC (might be unused) +* GbE (might be unused) +* ME +* BIOS + +[external programmer]: ../../../flash_tutorial/index.md |
