From patchwork Fri Jun 3 18:13:41 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geoff Levand X-Patchwork-Id: 69269 Delivered-To: patch@linaro.org Received: by 10.140.106.246 with SMTP id e109csp392371qgf; Fri, 3 Jun 2016 11:15:39 -0700 (PDT) X-Received: by 10.98.86.92 with SMTP id k89mr7674400pfb.76.1464977739202; Fri, 03 Jun 2016 11:15:39 -0700 (PDT) Return-Path: Received: from bombadil.infradead.org (bombadil.infradead.org. [2001:1868:205::9]) by mx.google.com with ESMTPS id e21si8823276pfj.74.2016.06.03.11.15.39 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 03 Jun 2016 11:15:39 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) client-ip=2001:1868:205::9; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) smtp.mailfrom=linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1b8tcG-0005rf-7P; Fri, 03 Jun 2016 18:14:40 +0000 Received: from merlin.infradead.org ([2001:4978:20e::2]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1b8tbM-00052O-95; Fri, 03 Jun 2016 18:13:44 +0000 Received: from geoff by merlin.infradead.org with local (Exim 4.85_2 #1 (Red Hat Linux)) id 1b8tbJ-0008U5-B7; Fri, 03 Jun 2016 18:13:41 +0000 Message-Id: In-Reply-To: References: From: Geoff Levand Patch-Date: Tue, 26 Jan 2016 15:29:29 +0900 Subject: [PATCH v17 07/13] arm64: limit memory regions based on DT property, usable-memory To: Catalin Marinas , Will Deacon Date: Fri, 03 Jun 2016 18:13:41 +0000 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , marc.zyngier@arm.com, kexec@lists.infradead.org, AKASHI Takahiro , James Morse , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org From: AKASHI Takahiro Crash dump kernel will be run with a limited range of memory as System RAM. On arm64, we will use a device-tree property under /chosen, linux,usable-memory = in order for primary kernel either on uefi or non-uefi (device tree only) system to hand over the information about usable memory region to crash dump kernel. This property will supercede entries in uefi memory map table and "memory" nodes in a device tree. Signed-off-by: AKASHI Takahiro --- arch/arm64/mm/init.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) -- 2.5.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 45f1319..f679918 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -249,10 +249,48 @@ static int __init early_mem(char *p) } early_param("mem", early_mem); +static int __init early_init_dt_scan_usablemem(unsigned long node, + const char *uname, int depth, void *data) +{ + struct memblock_region *usablemem = (struct memblock_region *)data; + const __be32 *reg; + int len; + + usablemem->size = 0; + + if (depth != 1 || strcmp(uname, "chosen") != 0) + return 0; + + reg = of_get_flat_dt_prop(node, "linux,usable-memory", &len); + if (!reg || (len < (dt_root_addr_cells + dt_root_size_cells))) + return 1; + + usablemem->base = dt_mem_next_cell(dt_root_addr_cells, ®); + usablemem->size = dt_mem_next_cell(dt_root_size_cells, ®); + + return 1; +} + +static void __init fdt_enforce_memory_region(void) +{ + struct memblock_region reg; + + of_scan_flat_dt(early_init_dt_scan_usablemem, ®); + + if (reg.size) { + memblock_remove(0, PAGE_ALIGN(reg.base)); + memblock_remove(round_down(reg.base + reg.size, PAGE_SIZE), + ULLONG_MAX); + } +} + void __init arm64_memblock_init(void) { const s64 linear_region_size = -(s64)PAGE_OFFSET; + /* Handle linux,usable-memory property */ + fdt_enforce_memory_region(); + /* * Ensure that the linear region takes up exactly half of the kernel * virtual address space. This way, we can distinguish a linear address