> -----Original Message----- > From: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx] > Sent: Tuesday, November 25, 2014 12:57 PM > To: Alex Lemberg > Cc: linux-mmc; Chris Ball; Avi Shchislowski > Subject: Re: [PATCH 1/1] Production State Awareness support in host side > > On 25 November 2014 at 10:17, Alex Lemberg <Alex.Lemberg@xxxxxxxxxxx> > wrote: > > > > > >> -----Original Message----- > >> From: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx] > >> Sent: Monday, November 24, 2014 2:24 PM > >> To: Alex Lemberg > >> Cc: linux-mmc; Chris Ball; Avi Shchislowski > >> Subject: Re: [PATCH 1/1] Production State Awareness support in host > >> side > >> > >> [...] > >> > >> >> >> > >> >> >> I am not so sure we should finalize the production phase while > >> >> >> initializing the eMMC card like this. > >> >> >> > >> >> >> Certainly we should check the PSA state, but I think we should > >> >> >> return an error if we think the device hasn’t completed > >> >> >> production. It should be the responsibility for the > >> >> >> "programming tools" to finalize the > >> >> production, right!? > >> >> > > >> >> > According to eMMC spec, the switch to NORMAL should be done > >> >> > after device > >> >> soldering to final host (not programmer). > >> >> > Please refer to "Figure 32 — Recommended Soldering procedure" in > >> >> eMMC5.0 specification document. > >> >> > Also, since we are dealing with only "field" host here, we are > >> >> > not > >> >> touching/switching any other modes of PSA, but only Normal (field). > >> >> > This code should run only once - in the beginning of device life cycle. > >> >> > >> >> I get your point, but I am not so sure. > >> >> > >> >> To me, I wouldn't trust that the platform binaries has been > >> >> successfully programmed to the device, unless the programmer tool > >> >> takes care of switching the device to "normal". > >> >> > >> > > >> > Thanks Ulf! > >> > Also, please note - PSA PRE_SOLDERING_POST_WRITES mode intent to > >> > save device pre-loaded content during the soldering process. > >> > Flash data can be corrupted due to soldering procedure high > >> > temperature. So switching to Normal cannot be done by external > >> programmer. > >> > >> So, if flash data will be corrupted due to for example high > >> temperatures during soldering, how will that be detected when using the > "manual mode"? > >> > >> If that's the job for the platform software I fail to understand why > >> the PRE_SOLDERING_POST_WRITES state needs to exists at all!? > > > > The flow of "Manual Mode" is: > > Thanks for clarifying. > > > > > [skipping few common steps] > > ... > > Host (Programmer) sets PRODUCTION_STATE_AWARENESS to 0x1 > > (PRE_SOLDERING_WRITES) > > > > Host (Programmer) perform pre-soldering data loading and/or device > > configuration > > > > Host (Programmer) sets PRODUCTION_STATE_AWARENESS To 0x2 > > (PRE_SOLDERING_POST_WRITES). > > No writes past this point > > To repeat my question: > > _Unless_ there are no validation of the device soldering performed by the > "programmer tool" past this point, why couldn't the host set > PRODUCTION_STATE_AWARENESS to 0x0 (NORMAL) at this point instead? > If programmer set to NORMAL at this point, the programmed data can be corrupted during the soldering process. eMMC device will protect programmed data during the soldering process in PRE_SOLDERING_POST_WRITES (0x2) mode. BTW, when I am saying "Host (Programmer)" - I intend external programming machine. > > > > Device Soldering > > > > Host (field) sets PRODUCTION_STATE_AWARENESS to 0x0 (NORMAL) ... > > > > Hope this will answer... > > > > Kind regards > Uffe ��.n��������+%������w��{.n�����{��i��)�� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
