On 18 November 2014 19:41, Alex Lemberg <Alex.Lemberg@xxxxxxxxxxx> wrote: > Hi Ulf, > >> -----Original Message----- >> From: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx] >> Sent: Monday, November 17, 2014 3:34 PM >> To: Avi Shchislowski >> Cc: linux-mmc; Chris Ball; Alex Lemberg >> Subject: Re: [PATCH 1/1] Production State Awareness support in host side >> >> On 17 November 2014 13:52, Avi Shchislowski <avi.shchislowski@xxxxxxxxxxx> >> wrote: >> > Adding support for PSA (Production State Awareness) feature for all >> > eMMC devices with revision >=5.0 In this patch the eMMC driver will >> > check if device was completed its Production State mode, and will >> > switch it to Normal (field) mode. >> > Switching to normal mode signal the device to complete its work in >> > production mode and start working in regular performance mode. >> >> Please add some detail to what this patch does. Additionally why it's needed. > > In this patch driver should recognize if eMMC device (Rev >=5.0) was not switched > to Normal (0x00) PSA mode by storage vendor or Programmer house. > For this, we are checking if device was leaved in PRE_SOLDERING_POST_WRITES (0x02) > state - represents a state in which the device is in production and the host > (usually programmer) completed to load the content to the device. > The host (usually programmer) sets the device to this state after content was loaded > and just before soldering. > After soldering the device to real host (not programmer), the device should be switched to > Normal (0x00) mode. > The Normal (0x00) mode of PSA register represents a state in which the device is running > in the field and uses “regular” operations. > Leaving device in PRE_SOLDERING_POST_WRITES (0x02) might not allow to host write content > to the device. > > More details about PSA feature can be found in eMMC 5.0 spec (Jedec: > JESD84-B50.pdf) > http://www.jedec.org/standards-documents/technology-focus-areas/flash-memory-ssds-ufs-emmc/e-mmc > > Please let us know if more details required. Okay, that was far better. 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!? Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
