Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752830AbdHOWju (ORCPT ); Tue, 15 Aug 2017 18:39:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:41700 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751944AbdHOWjt (ORCPT ); Tue, 15 Aug 2017 18:39:49 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6044E21C98 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=helgaas@kernel.org Date: Tue, 15 Aug 2017 17:39:46 -0500 From: Bjorn Helgaas To: Niklas Cassel Cc: linux-omap@vger.kernel.org, linux-pci@vger.kernel.org, Niklas Cassel , linux-kernel@vger.kernel.org, Kishon Vijay Abraham I , Pratyush Anand Subject: Re: [PATCH 0/2] PCI: dwc: convert remaining dbi read/writes to dw_pcie_readX_dbi/dw_pcie_writeX_dbi Message-ID: <20170815223946.GQ32525@bhelgaas-glaptop.roam.corp.google.com> References: <20170714120735.11993-1-niklas.cassel@axis.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170714120735.11993-1-niklas.cassel@axis.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1658 Lines: 49 [+cc Kishon, Pratyush] On Fri, Jul 14, 2017 at 02:07:33PM +0200, Niklas Cassel wrote: > Since the introduction of the dw_pcie_readX_dbi/dw_pcie_writeX_dbi macros, > most dw_pcie_read(pci->dbi_base, ..)/dw_pcie_write(pci->dbi_base, ..) calls > have been converted to dw_pcie_readX_dbi/dw_pcie_writeX_dbi calls. > Convert the remaining calls. > > Niklas Cassel (2): > PCI: dwc: dra7xx: utilize dw_pcie_readX_dbi/dw_pcie_writeX_dbi macros > PCI: dwc: spear13xx: utilize dw_pcie_readX_dbi/dw_pcie_writeX_dbi > macros > > drivers/pci/dwc/pci-dra7xx.c | 14 ++++++-------- > drivers/pci/dwc/pcie-spear13xx.c | 22 ++++++++++------------ > 2 files changed, 16 insertions(+), 20 deletions(-) These patches are short, but obscure, e.g., - dw_pcie_read(pci->dbi_base + exp_cap_off + PCI_EXP_LNKCAP, 4, &val); + val = dw_pcie_readl_dbi(pci, exp_cap_off + PCI_EXP_LNKCAP); The original call path was: dw_pcie_read(addr, ...) readl(addr) and we're replacing it with the much more complicated: dw_pcie_readl_dbi __dw_pcie_read_dbi if (pci->ops->read_dbi) return pci->ops->read_dbi(pci, base, reg, size) dw_pcie_read(base + reg, size, &val) readl This is not functionally equivalent (the new path uses ops->read_dbi if it's set), so the changelog should say something about why we need this change. Neither dra7xx nor spear13xx sets .read_dbi, so my guess is this doesn't actually fix anything that's broken and this is just for consistency. That's fine, but I'm confused because I looked for some of the previous conversions you mentioned but couldn't find any. I'm lost in a maze of twisty little passages. Bjorn