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@titlepage
@title ThinkPad T500
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@node Top
@top ThinkPad T500

@menu
* ThinkPad T500::
* LCD compatibly::
@end menu

@node ThinkPad T500
@chapter ThinkPad T500
@anchor{#thinkpad-t500}
It is believed that all or most T500 laptops are compatible. See notes about @uref{../install/t500_external.html#cpu_compatibility,CPU compatibility} for potential incompatibilities.

There are two possible flash chip sizes for the T500: 4MiB (32Mbit) or 8MiB (64Mbit). This can be identified by the type of flash chip below the palmrest: 4MiB is SOIC-8, 8MiB is SOIC-16.

@strong{The T500 laptops come with the ME (and sometimes AMT in addition) before flashing libreboot. Libreboot disables and removes it by using a modified descriptor: see @uref{gm45_remove_me.html,gm45_remove_me.html}} (contains notes, plus instructions)

Flashing instructions can be found at @uref{../install/index.html#flashrom,../install/index.html#flashrom}

@uref{index.html,Back to previous index}.
@menu
* Compatibility without blobs::
@end menu

@node Compatibility without blobs
@section Compatibility (without blobs)
@anchor{#compatibility-without-blobs}
@menu
* Hardware virtualization vt-x::
@end menu

@node Hardware virtualization vt-x
@subsection Hardware virtualization (vt-x)
@anchor{#hardware-virtualization-vt-x}
The T500, when run without CPU microcode updates in coreboot, currently kernel panics if running QEMU with vt-x enabled on 2 cores for the guest. With a single core enabled for the guest, the guest panics (but the host is fine). Working around this in QEMU might be possible; if not, software virtualization should work fine (it's just slower).

On GM45 hardware (with libreboot), make sure that the @emph{kvm} and @emph{kvm_intel} kernel modules are not loaded, when using QEMU.

The following errata datasheet from Intel might help with investigation: @uref{http://download.intel.com/design/mobile/specupdt/320121.pdf,http://download.intel.com/design/mobile/specupdt/320121.pdf}

The T500 is almost identical to the X200, code-wise. See @uref{x200.html,x200.html}.

@node LCD compatibly
@chapter LCD compatibly
@anchor{#lcd-compatibly}
Not all LCD panels are compatible yet. See @uref{gm45_lcd.html,gm45_lcd.html}.
@menu
* Descriptor and Gbe differences::
* Hardware register dumps::
@end menu

@node Descriptor and Gbe differences
@section Descriptor and Gbe differences
@anchor{#descriptor-and-gbe-differences}
See @uref{../resources/misc/dumps/t500_x200_descriptor/descriptor_diff_t500_x200.txt,../resources/misc/dumps/t500_x200_descriptor/descriptor_diff_t500_x200.txt} and @uref{../resources/misc/dumps/t500_x200_descriptor/gbe_diff_t500_x200.txt,../resources/misc/dumps/t500_x200_descriptor/gbe_diff_t500_x200.txt}

The patches above are based on the output from ich9deblob on a factory.rom image dumped from the T500 with a SOIC-8 4MiB flash chip. The patch re-creates the X200 descriptor/gbe source, so the commands were something like:@* $ @strong{diff -u t500gbe x200gbe}@* $ @strong{diff -u t500descriptor x200descriptor}

ME VSCC table is in a different place and a different size on the T500. Libreboot disables and removes the ME anyway, so it doesn't matter.

The very same descriptor/gbe used on the X200 (generated by @uref{gm45_remove_me.html#ich9gen,ich9gen}) was re-used on the T500, and it still worked.

@node Hardware register dumps
@section Hardware register dumps
@anchor{#hardware-register-dumps}
The coreboot wiki @uref{http://www.coreboot.org/Motherboard_Porting_Guide,shows} how to collect various logs useful in porting to new boards. Following are outputs from the T500:

@itemize
@item
T500 with @strong{Macronix MX25L3205D} flash chip (4MiB, SOIC-8) and Lenovo BIOS 3.13 7VET83WW (EC firmware 1.06):
@itemize
@item
@uref{../resources/misc/dumps/t500log/,../resources/misc/dumps/t500log/}
@end itemize

@end itemize

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