From patchwork Wed Oct 20 02:03:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Leizhen (ThunderTown)" X-Patchwork-Id: 1543660 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=devicetree-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by bilbo.ozlabs.org (Postfix) with ESMTP id 4HYvMP537dz9sR4 for ; Wed, 20 Oct 2021 13:14:57 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230130AbhJTCRI (ORCPT ); Tue, 19 Oct 2021 22:17:08 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:24366 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229980AbhJTCRD (ORCPT ); Tue, 19 Oct 2021 22:17:03 -0400 Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4HYvFy20PfzRfHY; Wed, 20 Oct 2021 10:10:14 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Wed, 20 Oct 2021 10:14:40 +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 15.1.2308.15; Wed, 20 Oct 2021 10:14:39 +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 , Nicolas Saenz Julienne , Feng Zhou , Kefeng Wang Subject: [PATCH v15 09/10] of: fdt: Add memory for devices by DT property "linux,usable-memory-range" Date: Wed, 20 Oct 2021 10:03:16 +0800 Message-ID: <20211020020317.1220-10-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.26.0.windows.1 In-Reply-To: <20211020020317.1220-1-thunder.leizhen@huawei.com> References: <20211020020317.1220-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.178.55] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.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 | 47 ++++++++++++++++++++++++++++++++++++----------- 1 file changed, 36 insertions(+), 11 deletions(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 4546572af24bbf1..cf59c847b2c28a5 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -969,8 +969,16 @@ static void __init early_init_dt_check_for_elfcorehdr(unsigned long node) elfcorehdr_addr, elfcorehdr_size); } -static phys_addr_t cap_mem_addr; -static phys_addr_t cap_mem_size; +/* + * 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 + +static struct memblock_region cap_mem_regions[MAX_USABLE_RANGES]; /** * early_init_dt_check_for_usable_mem_range - Decode usable memory range @@ -979,20 +987,30 @@ static phys_addr_t cap_mem_size; */ static void __init early_init_dt_check_for_usable_mem_range(unsigned long node) { - const __be32 *prop; - int len; + const __be32 *prop, *endp; + int len, nr = 0; + struct memblock_region *rgn = &cap_mem_regions[0]; 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->base = dt_mem_next_cell(dt_root_addr_cells, &prop); + rgn->size = dt_mem_next_cell(dt_root_size_cells, &prop); + + pr_debug("cap_mem_regions[%d]: base=%pa, size=%pa\n", + nr, &rgn->base, &rgn->size); + + if (++nr >= MAX_USABLE_RANGES) + break; + + rgn++; + } - pr_debug("cap_mem_start=%pa cap_mem_size=%pa\n", &cap_mem_addr, - &cap_mem_size); } #ifdef CONFIG_SERIAL_EARLYCON @@ -1265,7 +1283,8 @@ bool __init early_init_dt_verify(void *params) void __init early_init_dt_scan_nodes(void) { - int rc = 0; + int i, rc = 0; + struct memblock_region *rgn = &cap_mem_regions[0]; /* Initialize {size,address}-cells info */ of_scan_flat_dt(early_init_dt_scan_root, NULL); @@ -1279,7 +1298,13 @@ void __init early_init_dt_scan_nodes(void) of_scan_flat_dt(early_init_dt_scan_memory, NULL); /* Handle linux,usable-memory-range property */ - memblock_cap_memory_range(cap_mem_addr, cap_mem_size); + memblock_cap_memory_range(rgn->base, rgn->size); + for (i = 1; i < MAX_USABLE_RANGES; i++) { + rgn++; + + if (rgn->size) + memblock_add(rgn->base, rgn->size); + } } bool __init early_init_dt_scan(void *params)