2 files changed, 98 insertions, 3 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 @@
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+<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"/>
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+    <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>
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+    <tspan x="332.182" y="-24.0245">BIOS</tspan>
+  </text>
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+    <g>
+      <g>
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+      <tspan x="332.572" y="-104.29">GBE</tspan>
+    </text>
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+    <tspan x="406.127" y="-68.513">Flash #0</tspan>
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+    <g>
+      <g>
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