Hi Ulf, > -----Original Message----- > From: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx] > Sent: Tuesday, December 02, 2014 11:31 AM > 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 15:55, Alex Lemberg <Alex.Lemberg@xxxxxxxxxxx> > wrote: > > > > > >> -----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. > > Exactly how will that be done? > > During the soldering process the eMMC card isn't powered. So how could it > protect itself better, just because the state is PRE_SOLDERING_POST_WRITES? The device will use "special" internal operations for saving content prior to device soldering, and will switch to "regular" after the soldering and getting "NORMAL" mode. > > Kind regards > Uffe ��.n��������+%������w��{.n�����{��i��)�� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
