From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751229AbbLJFFJ (ORCPT ); Thu, 10 Dec 2015 00:05:09 -0500 Received: from comal.ext.ti.com ([198.47.26.152]:34482 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750717AbbLJFFH (ORCPT ); Thu, 10 Dec 2015 00:05:07 -0500 Subject: Re: [PATCH v4 4/5] ARM: dts: DRA7: add entry for qspi mmap region To: Tony Lindgren References: <1448860515-28336-1-git-send-email-vigneshr@ti.com> <1448860515-28336-5-git-send-email-vigneshr@ti.com> <20151130223408.GJ23396@atomide.com> <565D25E6.4070206@ti.com> <20151201163950.GR23396@atomide.com> <566017A8.5040106@ti.com> CC: Brian Norris , Mark Brown , Rob Herring , Russell King , "hramrach@gmail.com" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-omap@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-mtd@lists.infradead.org" , "linux-spi@vger.kernel.org" From: Vignesh R Message-ID: <566907D7.6040003@ti.com> Date: Thu, 10 Dec 2015 10:34:23 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <566017A8.5040106@ti.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/03/2015 03:51 PM, Vignesh R wrote: > > > On 12/01/2015 10:09 PM, Tony Lindgren wrote: >> * Vignesh R [151130 20:46]: >>> On 12/01/2015 04:04 AM, Tony Lindgren wrote: >>>> ... >> >> OK. They are both on L3 main so that won't cause any issues for separate >> interconnect driver instances. As they are still separate targets flushing >> a posted write to one area will not flush anything to the other. >> > > I didn't quite understand what you meant by interconnect driver instance. > qspi_base and qspi_mmap region are tightly bound to each other and both > needs to be accessed by ti-qspi driver (though different targets). > Besides qspi_mmap region is only used to read data, there will not be > any write accesses to this target. Are you saying this binding is not > viable? > As I stated above qspi_base and qspi_mmap region are tightly bound, there is no way to use qspi_mmap region w/o accessing qspi_base. So I am planning to keep them as it is. I will move qspi_ctrlmod to use syscon. Something like: qspi: qspi@4b300000 { compatible = "ti,dra7xxx-qspi"; reg = <0x4b300000 0x100>, <0x5c000000 0x4000000>, reg-names = "qspi_base", "qspi_mmap"; syscon-chipselects = <&scm_conf 0x558>; #address-cells = <1>; #size-cells = <0>; spi-max-frequency = <48000000>; ti,hwmods = "qspi"; }; Do you think this is not viable in future? -- Regards Vignesh