From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9BD0C3A5A6 for ; Fri, 30 Aug 2019 07:12:29 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A864322CE3 for ; Fri, 30 Aug 2019 07:12:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="GHiY//Jd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A864322CE3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=yVk6w1QkyDnH0x4A2mFJ4TgSyvnE1qJ4bq+2Hi/JGCc=; b=GHiY//JdEHlaL4 gDSidht8Aov0eHap2rzpnpJnQnPR1Xrk94+Uuc29v3D6A1G0RROTSamFuCTPd7r456IUIuPQYyKoG zP5byBa9e/XJVAY+HyZmngK/7wPreqDdCzg9yaaI3VVm+0atZXlAgfFZFBEPzl9r+LoZaczh/0ly/ ZUPuV+vDytR74MaPBb6w+QYpZZyLVoAtfiLS1FjyB9Qp6pHSl8oP5YVm8vgStEzJdg59hwFt7UAvb cr9mrowmpjX0I87o5FTx6HcdBA4bWA5YROpr14WA3huFYwGJIvnabrANsOIIMEg6GwxNI0IADzSiW rWo4GTEw94ifAPIdwXqg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i3b4z-0003wo-LJ; Fri, 30 Aug 2019 07:12:17 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190] helo=huawei.com) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1i3b1s-0001o8-7A; Fri, 30 Aug 2019 07:09:23 +0000 Received: from DGGEMS401-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id EBC49FEB3CFAD5B8A4FE; Fri, 30 Aug 2019 15:09:00 +0800 (CST) Received: from localhost.localdomain.localdomain (10.175.113.25) by DGGEMS401-HUB.china.huawei.com (10.3.19.201) with Microsoft SMTP Server id 14.3.439.0; Fri, 30 Aug 2019 15:08:52 +0800 From: Chen Zhou To: , , , , , , Subject: [PATCH v6 3/4] arm64: kdump: add memory for devices by DT property, low-memory-range Date: Fri, 30 Aug 2019 15:11:59 +0800 Message-ID: <20190830071200.56169-4-chenzhou10@huawei.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190830071200.56169-1-chenzhou10@huawei.com> References: <20190830071200.56169-1-chenzhou10@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.113.25] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190830_000905_957618_D2810B76 X-CRM114-Status: GOOD ( 11.15 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Chen Zhou , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, horms@verge.net.au, guohanjun@huawei.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org If we want to reserve crashkernel above 4G, we could use parameters "crashkernel=X crashkernel=Y,low", in this case, specified size low memory is reserved for crash dump kernel devices and never mapped by the first kernel. This memory range is advertised to crash dump kernel via DT property under /chosen, linux,low-memory-range= Crash dump kernel reads this property at boot time and call memblock_add() after memblock_cap_memory_range() has been called. Signed-off-by: Chen Zhou --- arch/arm64/mm/init.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index c99f845..a376b18 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -294,6 +294,26 @@ static int __init early_mem(char *p) } early_param("mem", early_mem); +static int __init early_init_dt_scan_lowmem(unsigned long node, + const char *uname, int depth, void *data) +{ + struct memblock_region *lowmem = data; + const __be32 *reg; + int len; + + if (depth != 1 || strcmp(uname, "chosen") != 0) + return 0; + + reg = of_get_flat_dt_prop(node, "linux,low-memory-range", &len); + if (!reg || (len < (dt_root_addr_cells + dt_root_size_cells))) + return 1; + + lowmem->base = dt_mem_next_cell(dt_root_addr_cells, ®); + lowmem->size = dt_mem_next_cell(dt_root_size_cells, ®); + + return 1; +} + static int __init early_init_dt_scan_usablemem(unsigned long node, const char *uname, int depth, void *data) { @@ -324,13 +344,21 @@ static void __init fdt_enforce_memory_region(void) if (reg.size) memblock_cap_memory_range(reg.base, reg.size); + + of_scan_flat_dt(early_init_dt_scan_lowmem, ®); + + if (reg.size) + memblock_add(reg.base, reg.size); } void __init arm64_memblock_init(void) { const s64 linear_region_size = -(s64)PAGE_OFFSET; - /* Handle linux,usable-memory-range property */ + /* + * Handle linux,usable-memory-range and linux,low-memory-range + * properties. + */ fdt_enforce_memory_region(); /* Remove memory above our supported physical address size */ -- 2.7.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel