Hi, Yes, the understanding in your latest reply is correct.
Best Regards, Hao Wu From: Mike M [mailto:[email protected]] Sent: Monday, December 24, 2018 10:04 AM To: [email protected] Cc: Ni, Ruiyu; Wang, Jian J; Wu, Hao A Subject: Re: Question about UfsPassThruDxe driver Sorry for the noise. Once I sent this question I understood this code. I overlooked UTP_TRD and UTP_TR_PRD declarations where lower 32-bit of a physical address declared as a bitfield... There are no shifts when HCI programmed via MMIO. On Sat, Dec 22, 2018 at 1:43 AM Mike M <[email protected]<mailto:[email protected]>> wrote: Dear MdeModulePkg maintainers, I'm a bit baffled about a way physical addresses passed to UFS HCI at UfsPassThruDxe driver. For example, UFS HCI V.2.1 declares Data Base Address in PRDT structure as two 32 bit words, where bits 0 and 1 of a physical address are reserved. As well UTP Command Descriptor Base Address (UCDBA) shall be aligned to 128-byte address, i.e. bits [06:00] are reserved. In common such reserved bits are being cleared by AND operation with appropriate mask, while in UfsPassThruDxe right shift operator is used as below: Prdt[PrdtIndex].DbAddr = (UINT32)RShiftU64 ((UINT64)(UINTN)Remaining, 2); Prdt[PrdtIndex].DbAddrU = (UINT32)RShiftU64 ((UINT64)(UINTN)Remaining, 32); and Trd->UcdBa = (UINT32)RShiftU64 ((UINT64)CmdDescPhyAddr, 7); Trd->UcdBaU = (UINT32)RShiftU64 ((UINT64)CmdDescPhyAddr, 32); How does UFS HCI deal with such values? This doesn't look correct. Would you like I prepare a patch replacing RShiftU64 operator with bitwise AND operator for lower 32-bit of a physical address value? _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
