Mac OS X on x86 Hardware 2008–2024 Technical Archive
InfiniteMac OSx86 › OSx86 Core & 10.X › Memory controller in DSDT
6,606 reads · 2009-08-28 – 2009-09-12
Note 10.X Core DSDT

Memory controller in DSDT

Does anyone know what part of a Mac DSDTs that operates the memory controller?

Primary Author
@kDawg Published 2009-08-28
Collection
OSx86 Core & 10.X
Archival Footprint
6,606 historical reads · 2 curated field notes (from 5 dispatches) · 2009-08-28 – 2009-09-12
Credited Voices (3)
@kDawg (3)@Firmware@uman

Does anyone know what part of a Mac DSDTs that operates the memory controller?

Author Updates & Technical Revisions

Follow-up dispatches by @kDawg

Author Update #1 @kDawg 2009-09-09 ↳ Re: @Firmware
@FirmwareThere is no description of the "memory controller" in the DSDT. However, the part of the chipset containing the memory controller (northbridge) usually does a lot more stuff, and that is mentioned. What are you looking for in particular?

Just trying to cross-reference things in the lspci with devices in the DSDT.

For instance this device:
00:00.0 Host bridge [0600]: Intel Corporation Eaglelake DRAM Controller [8086:2e20] (rev 03)

I can't reference this with any functionality as far as OS X in concerned. The OS just seems to ignore it.

Author Update #2 @kDawg 2009-09-12 ↳ Re: @uman
@umanFor Intel northbridges, you typically subtract 2 from the device id of your graphics device (in your case 2e12) to get the device id of the chipset "bridge". See: http://en.wikipedia.org/wiki/Intel_GMA ↗ for details. On both the MacBook X3100 and some HackBooks X3100, there is a device in ioreg called MCHC ("acpi-path" =…

Thanks for the great info!

Synthesized Community Field Notes

2 technical responses curated from 5 original dispatches

Field Note #1 @Firmware 2009-09-09

There is no description of the "memory controller" in the DSDT. However, the part of the chipset containing the memory controller (northbridge) usually does a lot more stuff, and that is mentioned. What are you looking for in particular?

Field Note #2 @uman 2009-09-12 ↳ Re: @kDawg

For Intel northbridges, you typically subtract 2 from the device id of your graphics device (in your case 2e12) to get the device id of the chipset "bridge". See: http://en.wikipedia.org/wiki/Intel_GMA ↗ for details.

On both the MacBook X3100 and some HackBooks X3100, there is a device in ioreg called MCHC ("acpi-path" = "IOACPIPlane:/_SB/PCI0/MCHC@0") that is registered against the chipset bridge.

A good source for decoding some of the DSDT mysteries WRT to northbridges is here: tracker.core boot.org/trac/coreboot/browser/trunk/coreboot-v2/src/northbridge/intel/i945/acpi?rev=4455

-u

@kDawg00:00.0 Host bridge [0600]: Intel Corporation Eaglelake DRAM Controller [8086:2e20] (rev 03) I can't reference this with any functionality as far as OS X in concerned. The OS just seems to ignore it.
Sources & Contributor Provenance (3 credited usernames · Thread #3810)
UsernameDossier ContributionDispatchesActive Window
@kDawgPrimary Author32009-08-28 → 2009-09-12
@FirmwareContributor12009-09-09
@umanContributor12009-09-12