On 11/9/20 9:41 AM, Andy Shevchenko wrote: > On Mon, Nov 9, 2020 at 4:40 PM Andy Shevchenko > <andy.shevchenko@xxxxxxxxx> wrote: >> >> On Mon, Nov 9, 2020 at 4:34 PM Sean Anderson <seanga2@xxxxxxxxx> wrote: >>> On 11/9/20 9:25 AM, Serge Semin wrote: >>>> On Sat, Nov 07, 2020 at 05:13:50PM +0900, Damien Le Moal wrote: >> >> ... >> >>>> Are you sure they have been moved from [0, 3] to [16, 20]? I don't have the >>>> manual for the 4.0x version of the core, but according to this patch: >>>> https://patchwork.kernel.org/project/spi-devel-general/patch/1575907443-26377-7-git-send-email-wan.ahmad.zainie.wan.mohamad@xxxxxxxxx/ >>>> it has been ok to use the lowest four bits for DFS setting. Is the commit >>>> message misleading there? >>> >>> This commit message is a truncated version of [1]. >> >> I don't see how they are related. I think this commit message is specifically taken from v3 of that patch [2]. However, I had not gotten a chance to have a look at the datasheet at that point, so it is a bit misleading (e.g. showing dfs for devices with SSI_MAX_XFER_SIZE=32, even though it is all zeros for those devices). In any case, the diagram is taken from that patch. [2] https://patchwork.ozlabs.org/project/uboot/patch/20200914153503.91983-7-seanga2@xxxxxxxxx/ > > For DW_ssi v1.x DFS is always for transfers up to 32-bit. Do you mean DWC_ssi? > >>> Importantly, DFS is >>> valid when SSI_MAX_XFER_SIZE=16. When it =32, then DFS_32 must be used >>> (since DFS is constant 0xF). Since SSI_MAX_XFER_SIZE is a synthesis >>> parameter, there exist devices where DFS must be used, and also where >>> DFS_32 must be used. >>> >>> [1] https://patchwork.ozlabs.org/project/uboot/patch/20201016225755.302659-10-seanga2@xxxxxxxxx/ > > >
