From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Nowicki Subject: [PATCH v3 1/9] x86, pci: Clean up comment about buggy MMIO config space access for AMD Fam10h CPUs. Date: Tue, 10 Mar 2015 12:35:12 +0100 Message-ID: <1425987320-15020-2-git-send-email-tomasz.nowicki@linaro.org> References: <1425987320-15020-1-git-send-email-tomasz.nowicki@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1425987320-15020-1-git-send-email-tomasz.nowicki@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: bhelgaas@google.com, wangyijing@huawei.com, arnd@arndb.de, hanjun.guo@linaro.org, Liviu.Dudau@arm.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, rjw@rjwysocki.net, al.stone@linaro.org Cc: linaro-acpi@lists.linaro.org, linux-pci@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, Tomasz Nowicki , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-acpi@vger.kernel.org - fix typo - improve explanation - add reference to the related document Signed-off-by: Tomasz Nowicki --- arch/x86/include/asm/pci_x86.h | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h index fa1195d..d024f4d 100644 --- a/arch/x86/include/asm/pci_x86.h +++ b/arch/x86/include/asm/pci_x86.h @@ -152,10 +152,13 @@ extern struct list_head pci_mmcfg_list; /* * AMD Fam10h CPUs are buggy, and cannot access MMIO config space - * on their northbrige except through the * %eax register. As such, you MUST - * NOT use normal IOMEM accesses, you need to only use the magic mmio-config + * on their northbridge except through the * %eax register. As such, you MUST + * NOT use normal IOMEM accesses, you need to only use the magic mmio_config_* * accessor functions. - * In fact just use pci_config_*, nothing else please. + * + * Please refer to the following doc: + * "BIOS and Kernel Developer's Guide (BKDG) For AMD Family 10h Processors", + * rev. 3.48, sec 2.11.1, "MMIO Configuration Coding Requirements". */ static inline unsigned char mmio_config_readb(void __iomem *pos) { -- 1.9.1