From patchwork Thu Apr 14 21:21:37 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geoff Levand X-Patchwork-Id: 65859 Delivered-To: patch@linaro.org Received: by 10.140.93.198 with SMTP id d64csp834565qge; Thu, 14 Apr 2016 14:32:17 -0700 (PDT) X-Received: by 10.66.66.10 with SMTP id b10mr24525220pat.12.1460669537148; Thu, 14 Apr 2016 14:32:17 -0700 (PDT) Return-Path: Received: from bombadil.infradead.org (bombadil.infradead.org. [198.137.202.9]) by mx.google.com with ESMTPS id qe4si9604442pab.195.2016.04.14.14.32.17 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Apr 2016 14:32:17 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 198.137.202.9 as permitted sender) client-ip=198.137.202.9; 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 198.137.202.9 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 1aqoqv-0000EW-DL; Thu, 14 Apr 2016 21:31:05 +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 1aqohr-0006Yz-Mf; Thu, 14 Apr 2016 21:21:43 +0000 Received: from geoff by merlin.infradead.org with local (Exim 4.85_2 #1 (Red Hat Linux)) id 1aqohl-0003Wd-PS; Thu, 14 Apr 2016 21:21:37 +0000 Message-Id: <9001c7d079ccc488b19579d6896993ac60087a9b.1460668521.git.geoff@infradead.org> In-Reply-To: References: From: Geoff Levand Patch-Date: Tue, 26 Jan 2016 15:29:29 +0900 Subject: [PATCH v16 16/20] arm64: limit memory regions based on DT property, usable-memory To: Catalin Marinas , Will Deacon Date: Thu, 14 Apr 2016 21:21:37 +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 3589d78..cfdc7c4 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -224,10 +224,48 @@ 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