Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934164AbcJFSiQ (ORCPT ); Thu, 6 Oct 2016 14:38:16 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:40827 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933813AbcJFSgq (ORCPT ); Thu, 6 Oct 2016 14:36:46 -0400 From: Reza Arbab To: Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Rob Herring , Frank Rowand , Andrew Morton Cc: Bharata B Rao , Nathan Fontenot , Stewart Smith , Alistair Popple , Balbir Singh , "Aneesh Kumar K.V" , Tang Chen , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v4 2/5] drivers/of: do not add memory for unavailable nodes Date: Thu, 6 Oct 2016 13:36:32 -0500 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1475778995-1420-1-git-send-email-arbab@linux.vnet.ibm.com> References: <1475778995-1420-1-git-send-email-arbab@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16100618-0020-0000-0000-000009F6A64E X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00005864; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000186; SDB=6.00765136; UDB=6.00365562; IPR=6.00540998; BA=6.00004791; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00012897; XFM=3.00000011; UTC=2016-10-06 18:36:42 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16100618-0021-0000-0000-0000563BE3AA Message-Id: <1475778995-1420-3-git-send-email-arbab@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-10-06_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1609300000 definitions=main-1610060324 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1252 Lines: 37 Respect the standard dt "status" property when scanning memory nodes in early_init_dt_scan_memory(), so that if the node is unavailable, no memory will be added. The use case at hand is accelerator or device memory, which may be unusable until post-boot initialization of the memory link. Such a node can be described in the dt as any other, given its status is "disabled". Per the device tree specification, "disabled" Indicates that the device is not presently operational, but it might become operational in the future (for example, something is not plugged in, or switched off). Once such memory is made operational, it can then be hotplugged. Signed-off-by: Reza Arbab --- drivers/of/fdt.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index b138efb..08e5d94 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -1056,6 +1056,9 @@ int __init early_init_dt_scan_memory(unsigned long node, const char *uname, } else if (strcmp(type, "memory") != 0) return 0; + if (!of_flat_dt_device_is_available(node)) + return 0; + reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l); if (reg == NULL) reg = of_get_flat_dt_prop(node, "reg", &l); -- 1.8.3.1