>
> This looks like a separate problem to me. On the SB2 there is this piece of code,
> simplified:
>
> Name(RQBF, Buffer (0xFF) {})
> CreateByteField (RQBF, 0x03, ALEN)
>
> // ...
> // GenericSerialBus/AttribRawProcessBytes access to fill RQBF
> // ...
>
> If (/* success and everything is valid */)
> {
> Local3 = (ALEN * 0x08)
> CreateField (RQBF, 0x20, Local3, ARB)
> Local4 = ARB /* \_SB_._SAN.RQSX.ARB_ */
> }
> Else
> {
> Local4 = 0x01 // or some other error code as integer
> }
>
> // ...
> // some more stuff
> // ...
>
> If ((ObjectType (Local4) == One /* Integer */))
> {
> // notify that an error has occurred
> }
> Else
> {
> // success and actually use data from Local4
> }
>
> The code in question basically unpacks a payload from some other
> management stuff sent over the OperationRegion.
>
> Here, ALEN is the length of a dynamically sized payload in bytes, which is
> obtained from the data returned by the OperationRegion access. This can for
> example be 4, making the field length 32 bit. So this is not an issue of the field
> length being larger than intmax bits, it actually is sometimes only 32 bits, or 8
> bits, depending on the response of the driver connected to the
> OperationRegion. Also the DSDT depends on that, see the example below.
>
> Just to reiterate, the code works fine for payloads with ALEN > 8 (so more than
> 8 bytes), but fails for anything less.
Forget what I said in the previous email. You are correct.
They treat bufferfields that are small enough to fit inside of an integer as a buffer or bufferfield.
I did a bunch of testing on windows and determined that, objects created by Create(Bit|Byte|Word|DWord|Qword)Field
work the same way on both interpreters. They get converted to Integers as outlined in the spec.
We simply need to stop perform the BufferField->Integer conversion for buffer fields created by the ASL CreateField() operators.
I'll get a solution hopefully sometime next week..
Thanks,
Erik
>
> Also note that this is not something that can be fixed by just telling the
> GenericSerialBus/OperationRegion driver to just return 9 bytes
> instead: There are length-checks on Local4 further down the line to validate it
> actually contains what was requested.
>
> An example of how this piece of code is actually used, if that helps (again
> simplified):
>
> Method (RQST, 1)
> {
> // pretty much the code above
> Return (Local4) // either payload or integer error code
> }
>
> Scope (_SB.BAT1)
> {
> Method (_STA, 0)
> {
> Local0 = RQST(0x01) // request battery status
>
> If ((ObjectType (Local0) == 0x03)) // is buffer type
> {
> If ((SizeOf (Local0) == 0x04)) // has length 4
> {
> CreateDWordField (Local0, 0, BAST)
> Return (BAST)
> }
> }
>
> Return (0x00) // return default value
> }
> }
>
>
> Regards,
> Maximilian
