Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752757AbdDZRSr (ORCPT ); Wed, 26 Apr 2017 13:18:47 -0400 Received: from mail-qk0-f196.google.com ([209.85.220.196]:33239 "EHLO mail-qk0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752628AbdDZRSR (ORCPT ); Wed, 26 Apr 2017 13:18:17 -0400 MIME-Version: 1.0 In-Reply-To: <1493126394-1239-4-git-send-email-deathsimple@vodafone.de> References: <1493126394-1239-1-git-send-email-deathsimple@vodafone.de> <1493126394-1239-4-git-send-email-deathsimple@vodafone.de> From: Andy Shevchenko Date: Wed, 26 Apr 2017 20:18:15 +0300 Message-ID: Subject: Re: [PATCH 3/4] x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 30h-3fh) Processors v2 To: =?UTF-8?Q?Christian_K=C3=B6nig?= Cc: helgaas@kernel.org, "linux-pci@vger.kernel.org" , dri-devel@lists.freedesktop.org, Platform Driver , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id v3QHItNH002834 Content-Length: 2490 Lines: 87 On Tue, Apr 25, 2017 at 4:19 PM, Christian König wrote: > From: Christian König > > Most BIOS don't enable this because of compatibility reasons. > > Manually enable a 64bit BAR of 64GB size so that we have > enough room for PCI devices. > +static void pci_amd_enable_64bit_bar(struct pci_dev *dev) > +{ > + uint32_t base, limit, high; Is u32 or uint32_t used actually in this file? > + struct resource *res, *conflict; > + unsigned i; unsigned int i; Reversed tree order. > + for (i = 0; i < 8; ++i) { > + pci_read_config_dword(dev, 0x80 + i * 0x8, &base); > + pci_read_config_dword(dev, 0x180 + i * 0x4, &high); > + > + /* Is this slot free? */ > + if ((base & 0x3) == 0x0) > + break; > + > + base >>= 8; > + base |= high << 24; > + > + /* Abort if a slot already configures a 64bit BAR. */ > + if (base > 0x10000) > + return; > + } > + if (i == 8) > + return; > + > + res = kzalloc(sizeof(*res), GFP_KERNEL); > + if (!res) > + return; > + > + res->name = "PCI Bus 0000:00"; > + res->flags = IORESOURCE_PREFETCH | IORESOURCE_MEM | > + IORESOURCE_MEM_64 | IORESOURCE_WINDOW; You are using this constant twice AFAICS, perhaps define it in generic pci.h and re-use? > + res->start = 0x100000000; > + res->end = 0xfd00000000 - 1; Perhaps you forgot ul / ull in many places in your code. Care to compile for 32-bit and fix the warnings? > + dev_info(&dev->dev, "adding root bus resource %pR\n", res); Some of your messages I think are rather dev_dbg() than dev_info(). > + base = ((res->start >> 8) & 0xffffff00) | 0x3; > + limit = ((res->end + 1) >> 8) & 0xffffff00; > + high = ((res->start >> 40) & 0xff) | > + ((((res->end + 1) >> 40) & 0xff) << 16); It would be nice to have the magics defined (just on top of this function) like #define PCI_AMD_BAR_XXX_MASK GENMASK(...) #define PCI_AMD_BAR_XXX_SHIFT nn > + pci_write_config_dword(dev, 0x180 + i * 0x4, high); > + pci_write_config_dword(dev, 0x84 + i * 0x8, limit); > + pci_write_config_dword(dev, 0x80 + i * 0x8, base); Ditto for pos:s. > + > + pci_bus_add_resource(dev->bus, res, 0); > +} -- With Best Regards, Andy Shevchenko