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

[TimeWalker]

I've just found out XPS13 has same chip for BIOS with same structure, if not even same SCT version ... the intel vbios is only SNB one, so
it must be SCT 2.0 like ours. There's one 00 00 00 00 00 00 00 00 45 0A occurence in PSA module which can unlock some menus presumably.
But that't not what I'm after .. changelog from A06 to A07 says "Win8 supported" which usually means nothing more than "Windows 2012" added to OSYS in DSDT..
There's another change: "Support new BIOS feature for battery", I've looked at PSA module and it hasn't any changes..
Actually I'm wrong ... for some reason a EC query has been added:

Code:

Method (_QB4, 0, NotSerialized)
                    {
                        P8XH (Zero, 0xB4)
                        Store (0x02, ^^^^AMW0.INF0)
                        Store (Zero, ^^^^AMW0.INF1)
                        Store (0xE02C, ^^^^AMW0.INF2)
                        Notify (AMW0, 0xD0)
                    }

Not sure what's the WMI code 0xE02C is fore, there's an Atheros BT module with such a PID, maybe to disable it or something ...

Dell hasn't even bothered to include Windows 8 in DSDT lol even tough they say "Win8 supported" in their changelog.

Code:

If (_OSI ("Windows 2009"))
                {
                    Store (0x07D9, OSYS)
                }

Only windows 7 is there... while on my vostro Windows 8 is properly coded in:

Code:

If (_OSI ("Windows 2012"))
                {
                    Store (0x07DC, OSYS)
                }

I still wonder what's the "BIOS feature for battery" .. but I have no desire to compare modules again If someone has - you are welcome.

Now, ITE IT8518E is also there - will try to figure something out ...
versions D13.For PHOENIX.EC Version.P0A28 and D13.For PHOENIX.EC Version.P0A27 from A03 and a A02 respectively have least possbile changes..
the only change from changelog betwheen these two says "Optimized system fan acoustics" so it can hint as to where tables are located, but oddly enough the firmware for ec looks somewhat different to my and what @jkbuha had sent me... but meh, worth looking anyway.

TODO:
-compare A02 with A03 and A03 with A04 to determine what has been done to suppress fan noise
-compare a06 to a07 to see what has been unlocked in bios in terms of battery

Changelog for XPS13 (L321x) is as follows:

A07
1. Win8 supported.
2. Support new BIOS feature for battery.

A06
1. Supports Win 7 & Win 8 PXE boot via USB 2 and SMSC 7500 Dongle
2. Resolves Intel iRST with TPM compatibility issues.
3. Supports TPM on Win8 .

A05
1. Supports Editing of Asset tag within the Bios menu. Support boot from USB LAN.

A04
1.Increased coverage of supported AC adapters
2.Updated LED behaviors for the keyboard backlight and the charge indicator
3.Improved S3 resume behavior
4.Further refinement of fan acoustics

A03
1. Optimized system fan acoustics

A02
Stock

[radosi]

I'm wondering where I can find DSDT aml file for 511z. I searched around but did't found any usable and I'm not sure that I can create good one with DSDT editor.

I Follow this instruction to install 10.8.2 OSx but can't manage with boot installation. system hang and restart on kernel patching probably because I use DSDT file from A19 bios 702x.

I have virtual machine with Lion for Xcode programming but want to try native OS.

If the is no way for 10.8.2, 10.7.4 could work for me too.

Thanks in advance.

[TimeWalker]

I'm wondering where I can find DSDT aml file for 511z. I searched around but did't found any usable and I'm not sure that I can create good one with DSDT editor.

I Follow this instruction to install 10.8.2 OSx but can't manage with boot installation. system hang and restart on kernel patching probably because I use DSDT file from A19 bios 702x.

I have virtual machine with Lion for Xcode programming but want to try native OS.

If the is no way for 10.8.2, 10.7.4 could work for me too.

Thanks in advance.

AFAK L502x DSDT is compatible, heck it's almost the same for all the models in the lineup.

My data mining on EC fimrware from XPS13 is not successful. I've started deciphering EC registers though. Here's a repo I created, because I've lost my original work on this subject :| never again ... https://github.com/Dolnor/V3450_commentary
Anyone with RWE, AIDA64/HWMonitor/HWInfo are welcome to assist .. don't know how useful this is, but I figured it might help looking for clues i EC firmware later on.

[kasar]

Anyone with RWE, AIDA64/HWMonitor/HWInfo are welcome to assist .. don't know how useful this is, but I figured it might help looking for clues i EC firmware later on.

I have most of those apps.

what do you need exactly from it ?

[TimeWalker]

You need patience lol.

You take EC map (from RWE) and try to determine what address holds what, play with hotkeys and cables .. etc. Meaning you check the address in the map, the address is made up by reading a number on the left, say 50, and number at the top, say 0A, so the address is 0x5A.
You then get your DSDT dump, decompile it to human readable and seek for Device (EC0 .
Then find your EC Memory map in DSDT.. OperationRegion (ECRM, EmbeddedControl, Zero, 0x0100).
Then browse to see your desired offset.. in the above case it was 0x5A, let's see:

Code:

Offset (0x55),
                        OTPC,   8, //x55
                        VGAT,   8, //8 bits make up 1 byte, so this is offset 0x56
                        CHPT,   8, //0x57
                        CPUT,   8, //0x58
                        SYST,   8,  //0x59
                        DTS1,   8,  //0x5A - this is CPU Package Temperature reported by Digital Thermal Sensing
                        DTS2,   8,  //0x5B - this is PCH Temperature reported by Digital Thermal Sensing
                        SYCS,   8,

Something like that... mostly you have to look at what's show in RWE EC map, find the address and variable in EC map in DSDT, then try to decipher the acronym used for variable and try to guess what it means, better off you associate a value from RWE EC map with something that is fixed and you can transcode hex into ascii or trace the routs of the value in DSDT (like Battery Make and Model for example). For values that are changing based on your input (remove AC, remove battery, toggle wi-fi, toggle keyboard illumination, toggle caps, etc .. ) it's pretty easy to figure what is what, for values that change themselves .. like temps, figuring out what they are is kind of hard, especially with temperature reporting. AIDA shows one thing (ie you see a value changes and matches with say DIMM thermo readin from AIDA, then you open up HWInfo64 and same temp says to be for Chipset, and DIMM is totally absent... so go figure).

[kasar]

hehe, yeah
patience isnt usually one of my virtues ^^

RWE?

[TimeWalker]

Read Write Everything

[TimeWalker]

Documented fan behavior over at git. Actually this was hard discovery lol. I can now somewhat override the speed of the fan, though it's not automated yet .. I've figured HWInfo64 has a pretty descent way of controlling the fan, but it lacks fine tuning. I've posted my research in their thread over at techinferno .. lets see if it somehow helps. Fan is preset to 4 states in EC: Reaching 1200RPM = Drops FAN to Off, 2800 RPM is never used, 3247 RPM are used when a low threshold (55C) is reached, 4321 RPM are used wen a high threshold (71C) is reached. There are no other fixed speeds, but you can get any desired speed if you manipulate registers.

I know it's possible to code in ACPI behavior for this, meaning DSDT can be edited to do certain things how I want them done. I already knew it was possible to drop RPMs by writing 0x00 into fan level register and this is the way I have been dealing with noise in OX, but now I know how to make the fan stick at a certain RPM or even make it turn off instantly. Just a matter of writing appropriate values to certain registers at certain time and in certain sequence.

[jkbuha]

I'm wondering where I can find DSDT aml file for 511z. I searched around but did't found any usable and I'm not sure that I can create good one with DSDT editor.

I Follow this instruction to install 10.8.2 OSx but can't manage with boot installation. system hang and restart on kernel patching probably because I use DSDT file from A19 bios 702x.

I have virtual machine with Lion for Xcode programming but want to try native OS.

If the is no way for 10.8.2, 10.7.4 could work for me too.

Thanks in advance.

TW is right - the xps15 DSDT is functionally equivalent to the L511z DSDT. Only difference is in the HDAudio, which needs to be resolved separately via patched AppleHDA, or else using VoodooHDA. Pop over to Insanely and just follow the L502x thread, downloading DoiX's great package.

Oh, and nice work TW re: fan control I still mess about with the thermal sensor in the bios, but to be honest in osx the cpu runs so cool because the nvidia gpu is switched off that the fan never really kicks off, well at least until a shockwave plugin in chrome loads...

[TimeWalker]

Found how one can override the automatic fan control from EC, though still figuring how to set custom rotation speeds. This is my approach for now

Code:

        Method (FANC, 1, NotSerialized) //Fan Control
        {
            If (LAnd (LEqual (^^EC.FLVL, 0x01), LEqual (^^EC.FANO, One))) //if fan is on for low threshold temp
            {
                If (LGreaterEqual(Arg0, 0x0CAA)) //if fan rpm >= 3242, low trip threshold
                {
                    Store (0x00, ^^EC.FLVL) //make fan speed drop gradually
                    If (LAnd (LGreater (Arg0, 0x0A28), LLess (^Arg0, 0x0BB8))) //if fan speed dropped between 3.0k and 2.6k RPM
                    {
                        Store (^^EC.TCTL, Zero) //disable auto mode, make fan speed stay at ~2.8K RPM, virtually silent mode
                        If (LAnd (LEqual (^^EC.FLVL, 0xFF), LGreaterEqual(^^EC.DTS1, 0x41))) //if temps on CPU package climb above 65C
                        {
                            Store (One, ^^EC.TCTL)) //EC auto control will kick back on
                        }
                    }
                }
            }
            
            If (LAnd (LEqual (^^EC.FLVL, 0x02), LEqual (^^EC.FANO, One))) //if fan is on for high threshold temp
            {
                If (LGreaterEqual(Arg0, 0x0FAA)) //if fan rpm >= 4010, high trip threshold
                {
                //do nothing for now
                }
             }
        }

                Method (FAN0, 0, NotSerialized)
                {
                    Store (^^EC.FANH, Local0)
                    Store (^^EC.FANL, Local1)
                    And (Local0, 0xFFFF, Local0)
                    And (Local1, 0xFFFF, Local1)
                    If (LNotEqual (Local0, Zero))
                    {
                        If (LEqual (Local0, 0xFFFF))
                        {
                            Store (Zero, Local0)
                        }
                        Else
                        {
                            Store (0x0100, Local2)
                            Multiply (Local0, Local2, Local3)
                            Add (Local1, Local3, Local4)
                            Store (Local4, Local0)
                        }
                    }
                    Else
                    {
                        Store (Zero, Local0)
                    }
            FANC (Local0)
                    Return (Local0)
                }