Tiger:
   Yes. Quark SmBusLib is the real library instance. Mde SmBusLib bases on PPI. Platform can decide to implement the real SmbusLib library instance or provide SmbusPPI implementation.

Thanks
Liming
From: devel@edk2.groups.io [mailto:devel@edk2.groups.io] On Behalf Of Tiger Liu(BJ-RD)
Sent: Monday, November 04, 2019 1:04 PM
To: Gao, Liming <liming.gao@intel.com>; devel@edk2.groups.io
Subject: Re: [edk2-devel] [edk2] Smbuslib and SmbusPpi

Hi, Liming:
I found two smbuslib implemented in below path:

1.  edk2-platforms\Silicon\Intel\QuarkSocPkg\QuarkNorthCluster\Library\SmbusLib

I named this smbuslib as quark-smbuslib

2.       MdePkg\Library\PeiSmbusLibSmbus2Ppi\
I name this smbuslib as Mde-smbuslib

My questions are:

1.       Quark-smbuslib provided some basic smbus operation functions, and these functions could be called by some PEIMs/Dxe drivers

So, it means not needed to implement gEfiPeiSmbus2Ppi for PEI phase?

(because quark-smbuslib has provided needed functions)

2.       Mde-smbuslib will consume gEfiPeiSmbus2PpiGuid
This smbuslib is independent , and just uses gEfiPeiSmbus2Ppi to encapsulate some functions.
So, a BIOS provider should implement a gEfiPeiSmbus2Ppi for PEI phase?

Thanks
发件人: Gao, Liming <liming.gao@intel.com<mailto:liming.gao@intel.com>>
发送时间: 2019年11月4日 11:31
收件人: devel@edk2.groups.io<mailto:devel@edk2.groups.io>; Tiger Liu(BJ-RD) <TigerLiu@zhaoxin.com<mailto:TigerLiu@zhaoxin.com>>
主题: RE: [edk2-devel] [edk2] Smbuslib and SmbusPpi

SmbusPpi is defined in PI spec. SmbusLib is defined in Edk2 MdePkg.

Edk2 PEIM can base on SmBusLib. SmBusLib implementation wraps SmBusPpi.

Thanks
Liming
From: devel@edk2.groups.io<mailto:devel@edk2.groups.io> [mailto:devel@edk2.groups.io] On Behalf Of Tiger Liu(BJ-RD)
Sent: Thursday, October 31, 2019 6:51 PM
To: devel@edk2.groups.io<mailto:devel@edk2.groups.io>; Gao, Liming <liming.gao@intel.com<mailto:liming.gao@intel.com>>
Subject: [edk2-devel] [edk2] Smbuslib and SmbusPpi

Hi, Liming:
I have a question about smbus access during pei phase.

I found there was not smbus ppi reference implementation in edk2-platform code base.
And there was a SmbusLib reference implementation lib.

So, PEIMs usually use functions provided by SmbusLib?
Not use PeiSmbusPpi’s interface functions?

Thanks

Best wishes,

保密声明：
本邮件含有保密或专有信息，仅供指定收件人使用。严禁对本邮件或其内容做任何未经授权的查阅、使用、复制或转发。
CONFIDENTIAL NOTE:
This email contains confidential or legally privileged information and is for the sole use of its intended recipient. Any unauthorized review, use, copying or forwarding of this email or the content of this email is strictly prohibited.

保密声明：
本邮件含有保密或专有信息，仅供指定收件人使用。严禁对本邮件或其内容做任何未经授权的查阅、使用、复制或转发。
CONFIDENTIAL NOTE:
This email contains confidential or legally privileged information and is for the sole use of its intended recipient. Any unauthorized review, use, copying or forwarding of this email or the content of this email is strictly prohibited.