Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753581Ab3FGM1d (ORCPT ); Fri, 7 Jun 2013 08:27:33 -0400 Received: from gloria.sntech.de ([95.129.55.99]:48387 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752047Ab3FGM1c (ORCPT ); Fri, 7 Jun 2013 08:27:32 -0400 From: Heiko =?iso-8859-1?q?St=FCbner?= To: Linus Walleij , Haojian Zhuang Subject: Re: [PATCH v2 1/8] clk: flag to use upper half of the register as change indicator Date: Fri, 7 Jun 2013 14:27:20 +0200 User-Agent: KMail/1.13.7 (Linux/3.2.0-3-686-pae; KDE/4.8.4; i686; ; ) Cc: "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Mike Turquette , Seungwon Jeon , Jaehoon Chung , Chris Ball , "linux-mmc@vger.kernel.org" , Grant Likely , Rob Herring , "devicetree-discuss@lists.ozlabs.org" , Russell King , Arnd Bergmann , Olof Johansson , Thomas Petazzoni References: <201306062107.58875.heiko@sntech.de> <201306062108.38587.heiko@sntech.de> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Message-Id: <201306071427.20512.heiko@sntech.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2021 Lines: 51 Am Freitag, 7. Juni 2013, 13:46:32 schrieb Linus Walleij: > On Thu, Jun 6, 2013 at 9:08 PM, Heiko St?bner wrote: > > There exist platforms, namely at least all Rockchip Cortex-A9 based ones, > > that don't use the paradigm of reading-changing-writing the register > > contents, but instead only write the changes to the register with a mask > > that indicates the changed bits. > > > > This patch adds flags and code to support the case where the lower 16 bit > > of hold the information and the upper 16 bit are used as mask to > > indicate the written changes. > > > > As hardware-specific flags should not be added to the common clk flags, > > the flags are added to gate, mux and divider clocks individually. > > > > Signed-off-by: Heiko Stuebner > > (...) > > > + if ((clk_gate_flags & CLK_GATE_MASK_UPPER_HALF) && bit_idx > 15) > > { + pr_err("%s: bit_idx %d invalid\n", __func__, bit_idx); > > + return ERR_PTR(-EINVAL); > > + } > > Now this looks *EXTREMELY* familiar to a patch just sent by Haojian > for HiSilicon. > > "[PATCH v2 3/6] clk: divider: add CLK_DIVIDER_HIWORD_MASK flag" > http://marc.info/?l=linux-arm-kernel&m=137035873916777&w=2 > > What kind of coincidence is this? Are Rockchip and HiSilicon using > the same silicon IP or are they of a common origin? (It is a small > world after all.) Now this is really interesting :-) and the handling really seems to follow the same pattern. > I think you two guys need to read each others patch sets closely > here. I'd like Haojian to look at Heiko's patches and Heiko to look > at Haojian's patches, just to make sure you're not actually writing > two drivers for the same hardware in the end. I'll take a look Heiko -- 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/