(UEFI) Dell XPS 15z L511z modded BIOS - and HOWTO

[HairyCube]

Thanks Andy! Will try soon.

jkbuha: yes, the table seems to be generated at startup. You can fetch your CPU PSS values by using AIDA64's ACPI tool to dump the current version of that particular SSDT table, but I have no idea if you can flash it back with modified values. I tried it, but the default values came back no matter what I did. It seems that Cpu0Ist in BIOS ROM serves only as a template.

[jkbuha]

I suspect they're populated by ME at startup.... can anyone else confirm?

[jkbuha]

Definitely something weird going on. I've compared the AIDA and BIOS SSDT outputs and there is clearly something happening at startup. Look at the difference in the files:

Code:

Comparing files acpi_ssdt_4.dsl and 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL ***** acpi_ssdt_4.dsl * * Disassembly of acpi_ssdt_4.bin, Thu Feb 14 14:18:10 2013 * ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL * * Disassembly of 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.ROM, Wed Feb 13 10:24:40 2013 * ***** ***** acpi_ssdt_4.dsl * Signature "SSDT" * Length 0x00000804 (2052) * Revision 0x01 * Checksum 0x93 * OEM ID "PmRef" ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL * Signature "SSDT" * Length 0x00000990 (2448) * Revision 0x01 * Checksum 0xC7 * OEM ID "PmRef" ***** ***** acpi_ssdt_4.dsl DefinitionBlock ("acpi_ssdt_4.aml", "SSDT", 1, "PmRef", "Cpu0Ist", 0x00003000) { ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL DefinitionBlock ("299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.aml", "SSDT", 1, "PmRef", "Cpu0Ist", 0x00003000) { ***** ***** acpi_ssdt_4.dsl External (CFGD) External (NPSS, IntObj) External (PDC0) ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL External (CFGD) External (PDC0) ***** ***** acpi_ssdt_4.dsl 0x00, // Bit Offset 0x0000000000001004, // Address ,) ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL 0x00, // Bit Offset 0x0000000000008000, // Address ,) ***** ***** acpi_ssdt_4.dsl Method (XPSS, 0, NotSerialized) { ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL Method (_PSS, 0, NotSerialized) // _PSS: Performance Supported States { ***** ***** acpi_ssdt_4.dsl Name (SPSS, Package (0x0A) { ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL Name (SPSS, Package (0x20) { ***** ***** acpi_ssdt_4.dsl { 0x00000A8D, 0x000088B8, 0x0000006E, 0x0000000A, 0x00000083, 0x00000000 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x00000A8C, 0x000088B8, 0x0000006E, 0x0000000A, 0x00000183, 0x00000001 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x00000898, 0x00006885, 0x0000006E, 0x0000000A, 0x00000283, 0x00000002 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x000007D0, 0x00005D47, 0x0000006E, 0x0000000A, 0x00000383, 0x00000003 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x00000708, 0x0000513B, 0x0000006E, 0x0000000A, 0x00000483, 0x00000004 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x00000640, 0x000046E5, 0x0000006E, 0x0000000A, 0x00000583, 0x00000005 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x00000578, 0x00003BCD, 0x0000006E, 0x0000000A, 0x00000683, 0x00000006 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x000004B0, 0x00003254, 0x0000006E, 0x0000000A, 0x00000783, 0x00000007 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, ***** ***** acpi_ssdt_4.dsl { 0x000003E8, 0x00002948, 0x0000006E, 0x0000000A, 0x00000883, 0x00000008 }, ***** 299141BB-211A-48A5-92C0-6F9A0A3A006E_5_640.DSL { 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000, 0x80000000 }, *****

Where on earth are the SSDT tables being populated? From the ME region?

[jkbuha]

Hi Andy

With your latest patch I think the DSDT & SSDT patching works well now. I'm still getting an empty SPSS & _PSS declaration, but the file compiles well and I'm not getting any errors. I'd obviously like to know why the declarations are not being properly populated but that is most likely due to the ME region of the firmware, not the PhoenixTool. Great work and thanks for a speedy patch!

Cheers
jkbuha

[TimeWalker]

I wasn't able to verify that DSDT reintegrates properly. I've submitted my feedback over at MDL.

[andyp2]

I wasn't able to verify that DSDT reintegrates properly. I've submitted my feedback over at MDL.

Confimed. Fixed in the 2.14 version posted in the MDL thread.
Andy

[jkbuha]

Confirmed that DSDT reintegrates properly in the latest version of 2.14. I can understand now how the DSDT integrates back into the BIOS.

Many thanks Andy for this.

Now can someone explain how the SSDT SPSS and _PSS values are populated at startup outside of the BIOS embedded DSDT and SSDTs?

[thorbsd]

Have you guys had any issues with the 15z and Windows 8?

I've got a relatively clean install of Win8 x64 with A12, and all the latest updates, and my system just hangs at the "shutting down" and "restarting" screen almost every time and I have to hold the power button to do a hard power off.

The problem still exists when I disable all non-microsoft services and all startup applications.

I've also turned off the fast boot option as well.

[jkbuha]

Hey thor

Interesting error - are you booting Win UEFI?

@anyone - any updates on my comments on SSDT/DSDT integration?

[thorbsd]

Hey thor

Interesting error - are you booting Win UEFI?

AFAIK I'm just booting off BIOS