From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Majewski Date: Sat, 12 Jan 2019 22:45:46 +0100 Subject: [U-Boot] dm: pinctrl: Prevent (re-)configuring pins when already done before relocation In-Reply-To: References: <20181218113050.6115-1-lukma@denx.de> <20181227154733.GI16433@bill-the-cat> <20190108235236.41aa25f5@jawa> <20190109002442.1f1c2ecf@jawa> Message-ID: <20190112224546.2df1d0ee@jawa> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Alex, > On Tue, Jan 8, 2019 at 11:24 PM Lukasz Majewski wrote: > > > > Hi Alex, > > > > > On Tue, Jan 8, 2019 at 10:52 PM Lukasz Majewski > > > wrote: > > > > > > > > Hi Alex, > > > > > > > > > On Thu, Dec 27, 2018 at 3:49 PM Tom Rini > > > > > wrote: > > > > > > > > > > > > On Tue, Dec 18, 2018 at 12:30:50PM +0100, Lukasz Majewski > > > > > > wrote: > > > > > > > This commit prevents from re-configuring pins if those > > > > > > > were configured before relocation. > > > > > > > > > > > > > > Some pins - like UART or DDR must be setup before > > > > > > > relocation (as they have 'u-boot,dm-pre-reloc' property > > > > > > > set in DTS). Without this change, those pins are > > > > > > > re-configured after relocation (pre_reloc_only = 0, so we > > > > > > > do not "continue"). Such behavior may be a problem for > > > > > > > DDR PAD configuration, as they might be already > > > > > > > leveled/tuned with original setup). > > > > > > > > > > > > > > Signed-off-by: Lukasz Majewski > > > > > > > > > > > > Applied to u-boot/master, thanks! > > > > > > > > > > > > > > > > I've bisected out to this commit and it's slightly broken > > > > > things for me on an AM3352. It all works fine so long as I > > > > > boot MLO from MMC (so the MMC is probed, pinctrl setup), but > > > > > if I boot from UART then I get to full U-Boot, MMC hasn't > > > > > been probed and the pinmuxing isn't set up for the MMC. > > > > > > > > I suppose that the pinmux node have set "u-boot,dm-pre-reloc" > > > > property? > > > > > > > > > > Yeah, well "u-boot,dm-spl", though now I re-read the docs I guess > > > that's equivalent to "u-boot,dm-pre-reloc" as I've no TPL. > > > > I do need to check this -> as in my case I do have > > "u-boot,dm-pre-reloc" property. And yes, in my case I do not have > > TPL too (just SPL). > > > > > > > > > The problem is not with lack of eMMC probing - it is with > > > > pinctrl nodes having "u-boot,dm-pre-reloc" set in DTS and the > > > > eMMC is probed after MLO/SPL. > > > > It looks like your use case implicitly depends on pinmux being > > > > reconfigured no matter if we are pre-relocated (MLO) or > > > > afterwards. > > > > > > Yes, that's a much clearer description... > > > > Frankly, your mail opened my eyes to a use case which was handled (I > > assume on purpose) with the old code - the "cross" boot with pinmux > > and devices. > > > > For example boot from UART (MLO/SPL) and then continue with eMMC > > (which require pinmux). > > > > So I guess this needs something like a bloblist to communicate the > initialisation state between MLO/SPL and u-boot, Yes. IMHO this is one way to do it. There is already a DM_FLAG_ACTIVATED, which indicates if the device was probed. However, it is not "dragged" from MLO / SPL to u-boot.img However, I think that we shall introduce a new flag - DM_FLAG_CONFIGURE_ONCE [*], which would indicate that the device need single configuration. This flag could be used with DM_PINMUX driver, to avoid re-configuration. The idea would be to use bloblist (only when [*] is set) to pass tuples: (driver_name, config_status) and in the core of DM just check if we shall re-configure the driver or not. > which I've not the > faintest idea where to start on. > > Horrible as they are, is a CONFIG symbol a possibility whilst we > figure out how to solve this properly? The bloblist can be activated with CONFIG_BLOBLIST > > I guess another option would be an additional two properties that give > the two behaviours, but that feels like something we don't want long > term. As we strive to use as little "u-boot,XXXXXX" extra properties to avoid problems with Linux re-sync, I think that we shall use bloblist. > > > -- > Alex Kiernan Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma at denx.de -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 488 bytes Desc: OpenPGP digital signature URL: