From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761510AbcIYSiv (ORCPT ); Sun, 25 Sep 2016 14:38:51 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:55856 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758385AbcIYShJ (ORCPT ); Sun, 25 Sep 2016 14:37:09 -0400 X-IMSS-HAND-OFF-DIRECTIVE: 127.0.0.1:10026 From: Reza Arbab To: Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Rob Herring , Frank Rowand , Jonathan Corbet , Andrew Morton Cc: Bharata B Rao , Nathan Fontenot , Stewart Smith , Alistair Popple , Balbir Singh , "Aneesh Kumar K.V" , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v3 2/5] drivers/of: do not add memory for unavailable nodes Date: Sun, 25 Sep 2016 13:36:53 -0500 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1474828616-16608-1-git-send-email-arbab@linux.vnet.ibm.com> References: <1474828616-16608-1-git-send-email-arbab@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16092518-0056-0000-0000-000001740CD1 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00005813; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000185; SDB=6.00761240; UDB=6.00362465; IPR=6.00536057; BA=6.00004754; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00012779; XFM=3.00000011; UTC=2016-09-25 18:37:06 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16092518-0057-0000-0000-000005A71955 Message-Id: <1474828616-16608-3-git-send-email-arbab@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-09-25_10:,, 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=8.0.1-1609020000 definitions=main-1609250356 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 9241c6e..59b772a 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_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