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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable 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 E065CC47247 for ; Mon, 4 May 2020 01:58:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C9A962073E for ; Mon, 4 May 2020 01:58:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726796AbgEDB6R (ORCPT ); Sun, 3 May 2020 21:58:17 -0400 Received: from mga14.intel.com ([192.55.52.115]:11877 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726377AbgEDB6Q (ORCPT ); Sun, 3 May 2020 21:58:16 -0400 IronPort-SDR: 6LfdbkYPd+JfdkcUiLH+o+VXQefuNJyMHg0jir3nv6GRFZpk8HqMS2Be3DI1S+ZGcuuh0PlgYm w98kerXG/Q4w== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 May 2020 18:58:16 -0700 IronPort-SDR: Ff3Y4xZ2QEk7wxYUQl6+j0WiEaUTuZZrEcn2LGSUgpJZeG8g0PG+BE1CCGK1w7xYYrWgwaxpSR qjMzawbxhmnQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,350,1583222400"; d="scan'208";a="262680308" Received: from linux.intel.com ([10.54.29.200]) by orsmga006.jf.intel.com with ESMTP; 03 May 2020 18:58:15 -0700 Received: from [10.214.154.10] (vramuthx-mobl1.gar.corp.intel.com [10.214.154.10]) by linux.intel.com (Postfix) with ESMTP id 773DE580609; Sun, 3 May 2020 18:58:09 -0700 (PDT) Reply-To: vadivel.muruganx.ramuthevar@linux.intel.com Subject: Re: [PATCH v4 2/2] mtd: rawnand: Add NAND controller support on Intel LGM SoC To: Boris Brezillon Cc: cheol.yong.kim@intel.com, devicetree@vger.kernel.org, masonccyang@mxic.com.tw, anders.roxell@linaro.org, vigneshr@ti.com, arnd@arndb.de, hauke.mehrtens@intel.com, richard@nod.at, brendanhiggins@google.com, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, robh+dt@kernel.org, linux-mtd@lists.infradead.org, miquel.raynal@bootlin.com, tglx@linutronix.de, qi-ming.wu@intel.com, andriy.shevchenko@intel.com References: <20200429104205.18780-1-vadivel.muruganx.ramuthevar@linux.intel.com> <20200429104205.18780-3-vadivel.muruganx.ramuthevar@linux.intel.com> <20200429162249.55d38ee8@collabora.com> <9d77c64c-d0f9-7a13-3391-d05bf458bdb1@linux.intel.com> <20200429164832.6800fc70@collabora.com> <2e83a2f7-853c-f0e2-f686-daf1e0649eae@linux.intel.com> <20200429173107.5c6d2f55@collabora.com> <1de9ba29-30f1-6829-27e0-6f141e9bb1e6@linux.intel.com> <20200430102114.29b6552f@collabora.com> <1df71cf7-4cae-4cd0-864c-0812bb2cc123@linux.intel.com> <20200430103658.4b0b979e@collabora.com> <1d5aec11-a7b5-01c2-6614-16e57c64511b@linux.intel.com> <20200430143600.27031639@collabora.com> <20200430150124.7856d112@collabora.com> From: "Ramuthevar, Vadivel MuruganX" Message-ID: <5bf637de-0ac1-1a24-0e91-aeb18bb563b4@linux.intel.com> Date: Mon, 4 May 2020 09:58:08 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20200430150124.7856d112@collabora.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Boris, Thank you very much for the review comments and your time... On 30/4/2020 9:01 pm, Boris Brezillon wrote: > On Thu, 30 Apr 2020 14:36:00 +0200 > Boris Brezillon wrote: > >> On Thu, 30 Apr 2020 17:07:03 +0800 >> "Ramuthevar, Vadivel MuruganX" >> wrote: >> >>>>>> The question is, is it the same value we have in nand_pa or it is >>>>>> different? >>>>>> >>>>> Different address which is 0xE1400000 NAND_BASE_PHY address. >>>> >>>> Then why didn't you tell me they didn't match when I suggested to pass >>> >>> sorry, because you keep asking nand_pa after that only I realized that. >>> >>>> nand_pa? So now the question is, what does this address represent? >>> >>> EBU-MODULE >>> _________ _______________________ >>> | | | |NAND CTRL | >>> | FPI BUS |==>| CS0(0x174) | 0xE100 ( 0xE14/0xE1C) NAND_PHY_BASE >>> |_________| |_CS1(0x17C)_|__________ | >>> >>> EBU_CONRTROLLER_BASE : 0xE0F0_0000 >>> HSNAND_BASE: 0xE100_0000 >>> NAND_CS0: 0xE140_0000 >>> NAND_CS1: 0xE1C0_0000 >>> >>> MEM_REGION_BASE_CS0: 0x17400 (internal to ebu controller ) >>> MEM_REGION_BASE_CS1: 0x17C00 >>> >> >> Hm, I wonder if we shouldn't use a 'ranges' property to describe this >> address translation. Something like >> >> ebu@xxx { >> ranges = <0x17400000 0xe1400000 0x1000>, >> <0x17c00000 0xe1c00000 0x1000>; >> reg = <0x17400000>, <0x17c00000>; >> reg-names = "cs-0", "cs-1"; >> } >> >> The translated address (0xE1X00000) will be available in res->start, >> and the non-translated one (0x17X00000) can be retrieved with >> of_get_address(). All you'd have to do then would be calculate the >> mask: >> >> mask = (translated_address & original_address) >> 22; >> num_comp_bits = fls(mask); >> WARN_ON(mask != GENMASK(num_comp_bits - 1, 0)); >> >> Which allows you to properly set the ADDR_SEL() register without >> relying on some hardcoded values: >> >> writel(original_address | EBU_ADDR_SEL_REGEN | >> EBU_ADDR_COMP_BITS(num_comp_bits), >> ebu_host->ebu + EBU_ADDR_SEL(csid)); >> >> That's quite important if we want to merge the xway NAND driver with >> this one. > > Looks like the translation is done at the FPI bus declaration level (see > [1]). We really need to see the big picture to take a wise decision > about the bindings. Would you mind pasting your dsti/dts files > somewhere? It feels like the NAND controller is a sub-part of a more > generic 'memory' controller, in which case the NAND controller should be > declared as a child of this generic memory bus (called localbus in [1], > but maybe EBU is more accurate). > > [1]https://github.com/xieyaxiongfly/Atheros_CSI_tool_OpenWRT_src/blob/master/target/linux/lantiq/files-4.14/arch/mips/boot/dts/vr9.dtsi#L162 for the ebu-nand node in the dts file. ebu_nand: ebu_nand@e0f00000 { compatible = "intel,lgm-ebu-nand"; reg = <0xe0f00000 0x100 //EBU_NAND controller 0xe1000000 0x300 //NAND ECC Extension access 0xe1400000 0x80000 0xe1c00000 0x10000>; reg-names = "ebunand", "hsnand", "nand_cs0", "nand_cs1"; dmas = <&dma0 8>, <&dma0 9>; dma-names = "ebu_rx", "ebu_tx"; clocks = <&cgu0 LGM_GCLK_EBU>; }; &ebu_nand { status = "disabled"; nand,cs = <1>; nand-ecc-mode = "hw"; pinctrl-names = "default"; pinctrl-0 = <&ebu_nand_base &ebu_cs1>; }; This is not comes under fpi in our devicetree. Regards Vadivel >