From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wm0-x242.google.com ([2a00:1450:400c:c09::242]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1fxwgo-0004ZR-9B for barebox@lists.infradead.org; Thu, 06 Sep 2018 15:59:28 +0000 Received: by mail-wm0-x242.google.com with SMTP id t25-v6so11794948wmi.3 for ; Thu, 06 Sep 2018 08:59:15 -0700 (PDT) MIME-Version: 1.0 References: <20180830050207.13192-1-andrew.smirnov@gmail.com> <20180906074834.kif6qcaqfcde26rt@pengutronix.de> In-Reply-To: <20180906074834.kif6qcaqfcde26rt@pengutronix.de> From: Andrey Smirnov Date: Thu, 6 Sep 2018 08:59:02 -0700 Message-ID: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH v2] clk: i.MX: Port Linux clock tree for i.MX51 and i.MX53 To: Sascha Hauer Cc: Barebox List On Thu, Sep 6, 2018 at 12:48 AM Sascha Hauer wrote: > > On Wed, Aug 29, 2018 at 10:02:07PM -0700, Andrey Smirnov wrote: > > Existing clock tree code for i.MX5 in Barebox predates DT and is not > > aware of it. This results in missing clocks on DT-based boards like > > RDU1 and Babbage. Port clock tree from Linux to resolve this > > problem. Old non-DT clock code is kept around for the sake of the > > boards that were never converted to use DT. > > Overall I am not happy with this patch. > > With this patch we now have two clock drivers for the i.MX5 - not only > in the source tree but also in the binaries. > > Yesterday I tried fleshing out the differences between both drivers. I > renamed "clks" to "clk", adjusted whitespaces, changed register defines > to the pattern "#define MXC_CCM_xxx (ccm_base + 0x*)". What I got was > quite a bit closer to the kernel driver but still not there. It revealed > some bugs in the kernel driver though. There are several differences in > the register layout between the i.MX50 and the i.MX51/53 (See > IMX5_CLK_ESDHC_A_SEL for example, MXC_CCM_CSCMR1[20:21] on i.MX51/53 and > MXC_CCM_CSCMR1[21:22] on the i.MX50). These are correctly abstracted > in the current barebox driver but not in the Linux driver, see > mx5_clocks_mx51_mx53_init() which doesn't exist in the Linux driver. > > So by switching to the Kernel clk driver we introduce a bunch of new > bugs into barebox which of course is unfortunate. > > Finally your patch does not compile on some configs > (efika-mx-smartbook_defconfig for example) since COMMON_CLK_OF_PROVIDER > is not selected. That's rather simple to fix of course. > > Which clocks are you missing? Maybe it would be better to add the > missing clocks to the barebox clock driver instead of adding a new one? > There's already a patch for that for original driver: http://lists.infradead.org/pipermail/barebox/2018-August/034413.html My hope was to use this as an opportunity to switch to using kernel code, but if we don't really want to pay the price for that, then I think Michael's patch should work just fine. Also, just out of curiosity, are you planning to upstream the fixes for bugs in kernel driver you found? Thanks, Andrey Smirnov _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox