From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 465E5C7618F for ; Thu, 18 Jul 2019 22:41:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 028DC21850 for ; Thu, 18 Jul 2019 22:41:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="p8RLhlmg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728135AbfGRWlh (ORCPT ); Thu, 18 Jul 2019 18:41:37 -0400 Received: from pandora.armlinux.org.uk ([78.32.30.218]:40522 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727950AbfGRWlh (ORCPT ); Thu, 18 Jul 2019 18:41:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=36BZtPLq/CaxSXzOtJxH8ypuKReHxIuhr0TFBrP0Uh4=; b=p8RLhlmg/xEimAbs3PuIbdPLk ti/Ji+4uUHPFAtQNzyvMbUf+8EbZXMAtSBGVIrJ8Us+hdJmthrLfVz+H7yOMPUGvpAXrIdosqLUdP FTl/m9APcimgYRv+tIza3tfLutBluv06M9/GD+12M2ovVj/OS8NYX+ZSsUXhaVm6cnWhF7KXhA+e2 AjlpljDfZfnEYw1R8fyOOQeZYIUoYV+cEW9iqVEzj0mPrKTaVqh1bhLudvI7jxsNcosU1etBMcfGv zV0pqK8/XXFRhChP6hg/cx8frSi/KxkkpXy9MX6HCLrx7cj7lcXnEvJoTpwUlk0jpN1BvbJn092QH 2/BXCrN5A==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:60470) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1hoF5h-0000zq-F0; Thu, 18 Jul 2019 23:41:33 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.89) (envelope-from ) id 1hoF5c-0002uC-ID; Thu, 18 Jul 2019 23:41:28 +0100 Date: Thu, 18 Jul 2019 23:41:28 +0100 From: Russell King - ARM Linux admin To: Stephen Boyd Cc: Michael Turquette , linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] ARM: sa1100: convert to common clock framework Message-ID: <20190718224128.bm7zfq3pg6psfai4@shell.armlinux.org.uk> References: <20190718163809.9D25D217F4@mail.kernel.org> <20190718174901.t6hlrdq6h3xhzlbj@shell.armlinux.org.uk> <20190718184308.C8E24205F4@mail.kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190718184308.C8E24205F4@mail.kernel.org> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org On Thu, Jul 18, 2019 at 11:43:07AM -0700, Stephen Boyd wrote: > Quoting Russell King - ARM Linux admin (2019-07-18 10:49:01) > > On Thu, Jul 18, 2019 at 09:38:08AM -0700, Stephen Boyd wrote: > > > Quoting Russell King (2019-06-29 03:14:10) > > > > Convert sa1100 to use the common clock framework. > > > > > > > > Signed-off-by: Russell King > > > > --- > > > > Please ack; this is part of a larger series. Thanks. > > > > > > Just a few minor comments but otherwise looks good to me. > > > > > > > diff --git a/arch/arm/mach-sa1100/clock.c b/arch/arm/mach-sa1100/clock.c > > > > index 6199e87447ca..523ef25618f7 100644 > > > > --- a/arch/arm/mach-sa1100/clock.c > > > > +++ b/arch/arm/mach-sa1100/clock.c > > > > +static const char * const clk_tucr_parents[] = { > > > > + "clk32768", "clk3686400", > > > > }; > > > > > > It would be great if you used the new way of specifying clk parents with > > > direct pointers instead of strings. See commit fc0c209c147f ("clk: Allow > > > parents to be specified without string names") for some details. > > > > I don't see at the moment how this is used with clk-mux.c - can you > > provide some hints? > > In this case both the parents are clk_hw pointers I think so an array > where first element is the clk_hw pointer to clk32768 and the second > element is the clk_hw pointer to clk3686400 would be assigned to > clk_init_data's parent_hws member. > > > struct clk_hw *clk_tucr_parents[] = { > &clk32768_hw, > &clk3686400_hw, > }; > > clk_tucr_init.parent_hws = clk_tucr_parents; Thanks. > > > > -static void clk_gpio27_enable(struct clk *clk) > > > > -{ > > > > /* > > > > * First, set up the 3.6864MHz clock on GPIO 27 for the SA-1111: > > > > * (SA-1110 Developer's Manual, section 9.1.2.1) > > > > */ > > > > + local_irq_save(flags); > > > > GAFR |= GPIO_32_768kHz; > > > > GPDR |= GPIO_32_768kHz; > > > > - TUCR = TUCR_3_6864MHz; > > > > + local_irq_restore(flags); > > > > + > > > > + return 0; > > > > } > > > > > > > > -static void clk_gpio27_disable(struct clk *clk) > > > > +static void clk_gpio27_disable(struct clk_hw *hw) > > > > { > > > > - TUCR = 0; > > > > + unsigned long flags; > > > > + > > > > + local_irq_save(flags); > > > > > > Why just disable irqs here? > > > > What do you mean? Do you mean "why are you only disabling IRQs and not > > taking a spinlock" or do you mean "why are you disabling IRQs here" ? > > I mean, why are you disabling irqs and not taking a spinlock? Must be > because there's already a spinlock in the clk framework? Nope - it's because there's no point taking a spinlock on something that is fundamentally only a uniprocessor architecture. There's never going to be a SA11x0 compatible SoC that has more than one core. > > > > GPDR &= ~GPIO_32_768kHz; > > > > GAFR &= ~GPIO_32_768kHz; > > > > + local_irq_restore(flags); > > > > } > > > > > > > > -static void clk_cpu_enable(struct clk *clk) > > > > -{ > > > > -} > > > > +static const struct clk_ops clk_gpio27_ops = { > > > > + .enable = clk_gpio27_enable, > > > > + .disable = clk_gpio27_disable, > > > > +}; > > > > > > > > -static void clk_cpu_disable(struct clk *clk) > > > > -{ > > > > -} > > > > +static const char * const clk_gpio27_parents[] = { > > > > + "tucr-mux", > > > > +}; > > > > > > > > -static unsigned long clk_cpu_get_rate(struct clk *clk) > > > > +static const struct clk_init_data clk_gpio27_init_data __initconst = { > > > > + .name = "gpio27", > > > > + .ops = &clk_gpio27_ops, > > > > + .parent_names = clk_gpio27_parents, > > > > + .num_parents = ARRAY_SIZE(clk_gpio27_parents), > > > > + .flags = CLK_IS_BASIC, > > > > > > CLK_IS_BASIC is gone. Please don't use it. > > > > The patch is against 5.1, and you're right, so that was removed for the > > version that ended up going upstream. > > Oh did this get sent to Linus already? I guess I should have reviewed > this earlier. Generally, SA11x0 stuff doesn't interest people, and patches I send out don't attract comments - so I tend to wait a couple of weeks before queuing them for merging. It hasn't yet been merged, but is in the queue - arm-soc has taken it into their late merges, but those haven't yet been sent. > > > > +}; > > > > + > > > > +/* > > > > + * Derived from the table 8-1 in the SA1110 manual, the MPLL appears to > > > > + * multiply its input rate by 4 x (4 + PPCR). This calculation gives > > > > + * the exact rate. The figures given in the table are the rates rounded > > > > + * to 100kHz. Stick with sa11x0_getspeed() for the time being. > > > [...] > > > > +static const struct clk_init_data clk_mpll_init_data __initconst = { > > > > + .name = "mpll", > > > > + .ops = &clk_mpll_ops, > > > > + .parent_names = clk_mpll_parents, > > > > + .num_parents = ARRAY_SIZE(clk_mpll_parents), > > > > + .flags = CLK_IS_BASIC | CLK_GET_RATE_NOCACHE | CLK_IS_CRITICAL, > > > > > > Please add a comment about these last two flags so we know why the rate > > > can't be cached and the clk is critical. > > > > Ok, I'll do that with a follow-up patch once the merge window is over. > > > > Ok, thanks. > -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up