piix4_smbus: How to deal with conflicting ACPI regions?

[Paul Menzel <paulepanter@xxxxxxxxxxxxxxxxxxxxx>]

Dear Linux folks,


using coreboot on the ASRock E350M1, the ACPI table contains the
following [1].

        $ more src/mainboard/asrock/e350m1/acpi/smbus.asl
        […]
        /* SMBUS Support */
        Mutex (SBX0, 0x00)
        OperationRegion (SMB0, SystemIO, 0xB00, 0x0C)
        	Field (SMB0, ByteAcc, NoLock, Preserve) {
        		HSTS,   8,  /* SMBUS status */
        		SSTS,   8,  /* SMBUS slave status */
        		HCNT,   8,  /* SMBUS control */
        		HCMD,   8,  /* SMBUS host cmd */
        		HADD,   8,  /* SMBUS address */
        		DAT0,   8,  /* SMBUS data0 */
        		DAT1,   8,  /* SMBUS data1 */
        		BLKD,   8,  /* SMBUS block data */
        		SCNT,   8,  /* SMBUS slave control */
        		SCMD,   8,  /* SMBUS shaow cmd */
        		SEVT,   8,  /* SMBUS slave event */
        		SDAT,   8   /* SMBUS slave data */
        }
        
        Method (WCLR, 0, NotSerialized) { /* clear SMBUS status register */
        	Store (0x1E, HSTS)
        	Store (0xFA, Local0)
        	While (LAnd (LNotEqual (And (HSTS, 0x1E), Zero), LGreater (Local0, Zero))) {
        		Stall (0x64)
        		Decrement (Local0)
        	}
        
        	Return (Local0)
        }

This causes a conflict later with piix4_smbus.

        ACPI: resource piix4_smbus [io  0x0b00-0x0b07] conflicts with ACPI region SMB0 [io 0xb00-0xb0b]

And the log message tells me to use an ACPI driver, if available.

Is there such a driver? I ask, because I was not able to find one. Would
that work with `decode-dimms`?

If the above is not possible, would the workaround be to remove the ACPI
SMBus configuration?


Thanks,

Paul


[1] http://review.coreboot.org/gitweb?p=coreboot.git;a=blob;f=src/mainboard/asrock/e350m1/acpi/e350m1/acpi/smbus.asl;h=e4ccfe3467c1b49edbf21b11add62872286684ed;hb=HEAD

Attachment: signature.asc
Description: This is a digitally signed message part