From patchwork Tue Nov 23 12:46:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Leizhen (ThunderTown)" X-Patchwork-Id: 12693458 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 40A6DC433EF for ; Tue, 23 Nov 2021 13:11:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=h7EUnlhfxVFDwifAy7JoylEb0MijG/opVmowmnCs8ak=; b=2QDVWl+SvovjrJ BxaKCUXFRtI9+RnVBMVeeXQIZ/K3WmKl2N1D/vrQz2i9TWbOJsO+GNRoAuroqPtaprsfOHm3SR8O4 sy3dY2t6YHYN2jv3ApJg26TByJcJSM9mBvpkR7ELEhvo0ZP8FGsFhVsp7UCeszKNpgvlOi7yzabLT tc7bMVWQJ8QEyl/1ahs4yNqnG5TH1leqa2qQIAXYuem4VTQQQ8+NBHh5GNr2fxpVK0WRODORyGUpd RjIS/qp5gIevzDrf/a2le++4a2tyuowYe0yDvoXHVeC6ZLEKy3JvRo1GOpG8DedLfgrnxG6R0QgU8 tryfqDuIFPSQiiAiteWA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mpVXf-002HAE-CI; Tue, 23 Nov 2021 13:09:00 +0000 Received: from szxga02-in.huawei.com ([45.249.212.188]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mpVEt-002Bwd-6d; Tue, 23 Nov 2021 12:49:41 +0000 Received: from dggpemm500021.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Hz3qR07Y8z91KL; Tue, 23 Nov 2021 20:49:07 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 23 Nov 2021 20:49:33 +0800 Received: from thunder-town.china.huawei.com (10.174.178.55) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 23 Nov 2021 20:49:31 +0800 From: Zhen Lei To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , , "H . Peter Anvin" , , Dave Young , Baoquan He , Vivek Goyal , Eric Biederman , , Catalin Marinas , "Will Deacon" , , Rob Herring , Frank Rowand , , Jonathan Corbet , CC: Zhen Lei , Randy Dunlap , Feng Zhou , Kefeng Wang , Chen Zhou Subject: [PATCH v16 10/11] of: fdt: Add memory for devices by DT property "linux, usable-memory-range" Date: Tue, 23 Nov 2021 20:46:45 +0800 Message-ID: <20211123124646.1995-11-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20211123124646.1995-1-thunder.leizhen@huawei.com> References: <20211123124646.1995-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211123_044935_608217_B2567CAF X-CRM114-Status: GOOD ( 15.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Chen Zhou When reserving crashkernel in high memory, some 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,usable-memory-range = We reused the DT property linux,usable-memory-range and made the low memory region as the second range "BASE2 SIZE2", which keeps compatibility with existing user-space and older kdump kernels. Crash dump kernel reads this property at boot time and call memblock_add() to add the low memory region after memblock_cap_memory_range() has been called. Signed-off-by: Chen Zhou Signed-off-by: Zhen Lei --- drivers/of/fdt.c | 36 ++++++++++++++++++++++++++---------- 1 file changed, 26 insertions(+), 10 deletions(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 37b477a51175359..1ea2a0b1657e3a9 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -967,6 +967,15 @@ static void __init early_init_dt_check_for_elfcorehdr(unsigned long node) static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND; +/* + * The main usage of linux,usable-memory-range is for crash dump kernel. + * Originally, the number of usable-memory regions is one. Now there may + * be two regions, low region and high region. + * To make compatibility with existing user-space and older kdump, the low + * region is always the last range of linux,usable-memory-range if exist. + */ +#define MAX_USABLE_RANGES 2 + /** * early_init_dt_check_for_usable_mem_range - Decode usable memory range * location from flat tree @@ -974,10 +983,9 @@ static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND; */ static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) { - const __be32 *prop; - int len; - phys_addr_t cap_mem_addr; - phys_addr_t cap_mem_size; + struct memblock_region rgn[MAX_USABLE_RANGES] = {0}; + const __be32 *prop, *endp; + int len, i = 0; if ((long)node < 0) return; @@ -985,16 +993,24 @@ static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) pr_debug("Looking for usable-memory-range property... "); prop = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len); - if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells))) + if (!prop) return; - cap_mem_addr = dt_mem_next_cell(dt_root_addr_cells, &prop); - cap_mem_size = dt_mem_next_cell(dt_root_size_cells, &prop); + endp = prop + (len / sizeof(__be32)); + while ((endp - prop) >= (dt_root_addr_cells + dt_root_size_cells)) { + rgn[i].base = dt_mem_next_cell(dt_root_addr_cells, &prop); + rgn[i].size = dt_mem_next_cell(dt_root_size_cells, &prop); + + pr_debug("cap_mem_regions[%d]: base=%pa, size=%pa\n", + i, &rgn[i].base, &rgn[i].size); - pr_debug("cap_mem_start=%pa cap_mem_size=%pa\n", &cap_mem_addr, - &cap_mem_size); + if (++i >= MAX_USABLE_RANGES) + break; + } - memblock_cap_memory_range(cap_mem_addr, cap_mem_size); + memblock_cap_memory_range(rgn[0].base, rgn[0].size); + for (i = 1; i < MAX_USABLE_RANGES && rgn[i].size; i++) + memblock_add(rgn[i].base, rgn[i].size); } #ifdef CONFIG_SERIAL_EARLYCON