Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752539AbaBMRKz (ORCPT ); Thu, 13 Feb 2014 12:10:55 -0500 Received: from mail-ea0-f175.google.com ([209.85.215.175]:36606 "EHLO mail-ea0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752396AbaBMRKx (ORCPT ); Thu, 13 Feb 2014 12:10:53 -0500 Message-ID: <52FCFC97.8050200@gmail.com> Date: Thu, 13 Feb 2014 18:10:47 +0100 From: Sebastian Hesselbarth User-Agent: Mozilla/5.0 (X11; Linux i686; rv:24.0) Gecko/20100101 Thunderbird/24.0 To: Thomas Petazzoni CC: Linus Walleij , Jason Cooper , Andrew Lunn , Gregory Clement , Ezequiel Garcia , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 00/13] pinctrl: mvebu: restructure resource allocation References: <1390869573-27624-1-git-send-email-sebastian.hesselbarth@gmail.com> <1392220776-30851-1-git-send-email-sebastian.hesselbarth@gmail.com> <20140213172620.76e760ba@skate> <52FCF59E.3090100@gmail.com> <20140213175914.205803a6@skate> In-Reply-To: <20140213175914.205803a6@skate> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/13/14 17:59, Thomas Petazzoni wrote: > On Thu, 13 Feb 2014 17:41:02 +0100, Sebastian Hesselbarth wrote: >>> Thanks again for working on this! I have boot tested this successfully >>> on an Armada XP platform, and it seems to behave normally, the debugfs >>> pinctrl contents make sense. >> >> I guess this is a Tested-by ? > > Yes. My tests were admittedly fairly light, but I believe good enough :) Ok. >>> I am not sure what you mean here in terms of the ordering for the >>> patches. I'm attaching several patches, and the first three patches >>> adapt your patch series to also cover 375 and 38x, assuming the pinctrl >>> support for 375 and 38x is merged before your patch series. >> >> Right. If 375/38x pinctrl goes in first (what I expect), I'd have to add >> corresponding patches. You already sent them, I'll pick them up. > > Ok, cool. Hopefully we can sort out the merging of those two patch > series for 3.15 with Linus Walleij. That is the plan - or rather get his Acked-by as we are lucky to have pinctrl/mvebu and touching nothing else. >>> I must say I dislike quite a bit this unnamed mpp controls mechanism. >>> Why isn't the name statically defined in the source code by the >>> MPP_MODE macro, which already takes as first argument the pin number? >> >> Honestly, the unnamed mpp control thing is a bit odd. But if you tell >> me how to create ~60 statically defined one pin groups out of a >> single-line macro, we can change that easily. >> >> Back when that unnamed mpp control thing was invented, I must have been >> to lazy to write e.g. >> >> MPP_FUNC_CTRL(0, 0, "mpp0", armada_xp_mpp_ctrl), >> MPP_FUNC_CTRL(1, 1, "mpp1", armada_xp_mpp_ctrl), >> MPP_FUNC_CTRL(2, 2, "mpp2", armada_xp_mpp_ctrl), >> ... >> MPP_FUNC_CTRL(66, 66, "mpp66", armada_xp_mpp_ctrl), >> >> instead of >> >> MPP_FUNC_CTRL(0, 66, NULL, armada_xp_mpp_ctrl), >> >> and generate the 66 names dynamically. > > Right. But what I meant is that we already have a place where we have > one macro call for each pin: when defining the MPP modes. So I was > thinking of simplifying the whole stuff by "merging" the notion of MPP > control with the notion of MPP mode. This way, when you do: > > MPP_MODE(0, > MPP_FUNCTION(...), > MPP_FUNCTION(...)), > MPP_MODE(1, > MPP_FUNCTION(...), > MPP_FUNCTION(...)), > MPP_MODE(2, > MPP_FUNCTION(...), > MPP_FUNCTION(...)), > [...] > MPP_MODE(65, > MPP_FUNCTION(...), > MPP_FUNCTION(...)), > > You can take this opportunity to generate: > > { "mpp0", ... }, > { "mpp1", ... }, > { "mpp2", ... }, > ... > { "mpp65", ... }, Ah, ok, I see. Yes that should be doable. We should definitely consider this for later, i.e. leave it now as is and rework later. >>> This is definitely good, but I'm wondering why the core cannot provide >>> helper functions for the generic case where we have 4 bits per pin in >>> contiguous registers. This would avoid duplicating the helper function >>> six times (you have four in your patch series, and we'll need two more >>> for A375 and A38x). >> >> I thought about it too, but we would need a soc specific callback >> anyway as you'll have to pass the base address somehow (and that is now >> known by soc specific stub only). My quick rule of thumb was that the >> amount of code replication would be almost the same. > > In pinctrl-mvebu.h, we could have: > > static inline int default_mpp_ctrl_get(void __iomem *base, unsigned int pid, unsigned long *config) > { > unsigned off = (pid / MVEBU_MPPS_PER_REG) * MVEBU_MPP_BITS; > unsigned shift = (pid % MVEBU_MPPS_PER_REG) * MVEBU_MPP_BITS; > > *config = (readl(base + off) >> shift) & MVEBU_MPP_MASK; > > return 0; > } > > static inline int default_mpp_ctrl_set(void __iomem *base, unsigned int pid, unsigned long config) > { > unsigned off = (pid / MVEBU_MPPS_PER_REG) * MVEBU_MPP_BITS; > unsigned shift = (pid % MVEBU_MPPS_PER_REG) * MVEBU_MPP_BITS; > unsigned long reg; > > reg = readl(base + off) & ~(MVEBU_MPP_MASK << shift); > writel(reg | (config << shift), base + off); > > return 0; > } > > which would slightly reduce the per-SoC code to: > > static int armada_370_mpp_ctrl_get(unsigned pid, unsigned long *config) > { > return default_mpp_ctrl_get(mpp_base, pid, config); > } > > static int armada_370_mpp_ctrl_set(unsigned pid, unsigned long config) > { > return default_mpp_ctrl_set(mpp_base, pid, config); > } > > but we admittedly cannot completely remove the per-SoC function, since > the mpp_base is now only known to each per-SoC driver. I guess I'll squash the above in for v4.. doesn't look that bad. Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/