On Mon, 2015-07-27 at 09:58 +0200, Ulf Hansson wrote: > On 25 July 2015 at 04:27, Scott Wood <scottwood@xxxxxxxxxxxxx> wrote: > > On Tue, 2015-07-21 at 15:02 +0200, Ulf Hansson wrote: > > > On 21 July 2015 at 11:45, Yangbo Lu <yangbo.lu@xxxxxxxxxxxxx> wrote: > > > > For T4240-R1.0-R2.0, the HOSTVER register has incorrcet vender > > > > version value and sdhc spec version value. This will break down > > > > the ADMA data transfer. So add workaround to get right value > > > > VVN=0x13, SVN = 0x1. > > > > > > So T4240-R1.0-R2.0 is the version of the controller, right? > > > > > > If I understand correct you are checking what CPU/SoC you are running > > > on, to figure out which controller version you are using, as that > > > can't be fetched (trusted) from the registers of the esdhc controller > > > itself!? > > > > > > Instead, you could deal with this directly in the DTS files. I assume > > > you have some DTS file for each SoC/board variant, right? > > > > No, we do not have a separate DTS file for each revision of an SoC -- and > > if > > we did, we'd constantly have people using the wrong one. > > > > > In principle, in your DTS file specific for the board/SoC that holds > > > the T4240-R1.0-R2.0 version of the controller, should add a specific > > > esdhc DT property to indicate this errata. > > > > No, because (in addition to the above issue about chip revisions) the > > device > > tree is stable ABI and errata are often discovered after device trees are > > deployed. > > Fair enough. Then what is your suggestion for the solution here? As I said in my comment on patch 2/3, read SVR from the device-config/guts MMIO block, which works on both PPC and ARM. -Scott -- 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
