From patchwork Wed Jul 31 12:51:58 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Szyprowski X-Patchwork-Id: 2836224 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 69128C0319 for ; Wed, 31 Jul 2013 12:54:20 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D2EA8202BE for ; Wed, 31 Jul 2013 12:54:18 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 31FC2202B4 for ; Wed, 31 Jul 2013 12:54:13 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1V4VuL-00085y-A6; Wed, 31 Jul 2013 12:53:38 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1V4Vu3-0005xi-2E; Wed, 31 Jul 2013 12:53:19 +0000 Received: from mailout1.samsung.com ([203.254.224.24]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1V4VtU-0005sk-HH for linux-arm-kernel@lists.infradead.org; Wed, 31 Jul 2013 12:52:48 +0000 Received: from epcpsbgm2.samsung.com (epcpsbgm2 [203.254.230.27]) by mailout1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0MQS00L7QX3G79Q0@mailout1.samsung.com> for linux-arm-kernel@lists.infradead.org; Wed, 31 Jul 2013 21:52:28 +0900 (KST) X-AuditID: cbfee61b-b7efe6d000007b11-1d-51f9088c6265 Received: from epmmp1.local.host ( [203.254.227.16]) by epcpsbgm2.samsung.com (EPCPMTA) with SMTP id 96.0A.31505.C8809F15; Wed, 31 Jul 2013 21:52:28 +0900 (KST) Received: from localhost.localdomain ([106.116.147.30]) by mmp1.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTPA id <0MQS004JJX2O1G70@mmp1.samsung.com>; Wed, 31 Jul 2013 21:52:28 +0900 (KST) From: Marek Szyprowski To: linux-arm-kernel@lists.infradead.org, linaro-mm-sig@lists.linaro.org, devicetree-discuss@lists.ozlabs.org Subject: [PATCH v4 3/4] drivers: of: add initialization code for dma reserved memory Date: Wed, 31 Jul 2013 14:51:58 +0200 Message-id: <1375275119-12787-4-git-send-email-m.szyprowski@samsung.com> X-Mailer: git-send-email 1.7.9.5 In-reply-to: <1375275119-12787-1-git-send-email-m.szyprowski@samsung.com> References: <1375275119-12787-1-git-send-email-m.szyprowski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrFLMWRmVeSWpSXmKPExsVy+t9jAd0ejp+BBq8uKVn8nXSM3eLA7Ies Fq/ObGSzONv0ht1ie+cMdosvVx4yWWx6fI3VYu2Ru+wWG14eZLJYcLyF1eLPdDmLU9c/s1l8 //aNzeLv9k0sFofftLNarJ/xmsVBwOP3r0mMHpf7epk8ds66y+6xeUm9x+1/j5k9zs9YyOhx 5UQTq8e6P6+YPPr/Gnj0bVnF6PHzpU4AdxSXTUpqTmZZapG+XQJXxrLO30wFG9Mq1s9awNTA 2BjSxcjJISFgItGwcQMbhC0mceHeeiCbi0NIYBGjxITj+5khnHYmiZkNC8Gq2AQMJbredgHZ HBwiAvkSq2fxgoSZBdpYJF5sYAGxhQXCJP60PmYHsVkEVCVOHv0AFucV8JCYf/sTM0irhICC xJxJNiBhTgFPiYM/94BNFwIqOTZ3ItsERt4FjAyrGEVTC5ILipPSc430ihNzi0vz0vWS83M3 MYJD/Jn0DsZVDRaHGAU4GJV4eGdc+h4oxJpYVlyZe4hRgoNZSYR3D+vPQCHelMTKqtSi/Pii 0pzU4kOM0hwsSuK8B1utA4UE0hNLUrNTUwtSi2CyTBycUg2M3nEPFKbyfc7tz9z//YD3VAl3 y6vPpZ7PyQmaEeY9qT/yeFXSbJFpzZ2fVb67OD8QXav6zfFjVVbN+Zvr1C5FWjIV7ef4byF0 oysz/KrM0xbVvEfPRL12rhPnaZla3hP9iIf7y9qzhn/1VE7zJSqZHH30qnVm26HoQh+GezPW XJKpZWXoex6pxFKckWioxVxUnAgArg+N6G0CAAA= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130731_085244_872743_108F078F X-CRM114-Status: GOOD ( 28.49 ) X-Spam-Score: -8.4 (--------) Cc: Laura Abbott , Arnd Bergmann , Tomasz Figa , Nishanth Peethambaran , Michal Nazarewicz , Grant Likely , Marc , Kyungmin Park , Sylwester Nawrocki , Olof Johansson , Sascha Hauer , Marek Szyprowski X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.7 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD,T_FRT_FOLLOW1,T_FRT_FOLLOW2,UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add device tree support for contiguous and reserved memory regions defined in device tree. Initialization is done in 2 steps. First, the memory is reserved, what happens very early when only flattened device tree is available. Then on device initialization the corresponding cma and reserved regions are assigned to each device structure. Signed-off-by: Marek Szyprowski Acked-by: Kyungmin Park Acked-by: Michal Nazarewicz --- Documentation/devicetree/bindings/memory.txt | 152 ++++++++++++++++++++++ drivers/of/Kconfig | 6 + drivers/of/Makefile | 1 + drivers/of/of_reserved_mem.c | 175 ++++++++++++++++++++++++++ include/asm-generic/dma-coherent.h | 6 + 5 files changed, 340 insertions(+) create mode 100644 Documentation/devicetree/bindings/memory.txt create mode 100644 drivers/of/of_reserved_mem.c diff --git a/Documentation/devicetree/bindings/memory.txt b/Documentation/devicetree/bindings/memory.txt new file mode 100644 index 0000000..4aece19 --- /dev/null +++ b/Documentation/devicetree/bindings/memory.txt @@ -0,0 +1,152 @@ +*** Memory binding *** + +The /memory node provides basic information about the address and size +of the physical memory. This node is usually filled or updated by the +bootloader, depending on the actual memory configuration of the given +hardware. + +The memory layout is described by the folllowing node: + +memory { + reg = <(baseaddr1) (size1) + (baseaddr2) (size2) + ... + (baseaddrN) (sizeN)>; +}; + +baseaddrX: the base address of the defined memory bank +sizeX: the size of the defined memory bank + +More than one memory bank can be defined. + + +*** Reserved memory regions *** + +In /memory/reserved-memory node one can create additional nodes +describing particular reserved (excluded from normal use) memory +regions. Such memory regions are usually designed for the special usage +by various device drivers. A good example are contiguous memory +allocations or memory sharing with other operating system on the same +hardware board. Those special memory regions might depend on the board +configuration and devices used on the target system. + +Parameters for each memory region can be encoded into the device tree +wit the following convention: + +[(label):] (name)@(address) { + compatible = "contiguous-memory-region", "reserved-memory-region"; + reg = <(address) (size)>; + (linux,contiguous-region); + (linux,default-contiguous-region); +}; + +label: label given to the defined region (optional) +name: an name given to the defined region +address: the base address of the defined region +size: the size of the memory region + +compatible: "contiguous-memory-region" - enables binding of this + region to Contiguous Memory Allocator (special region for + contiguous memory allocations, shared with movable system + memory, Linux kernel-specific), alternatively if + "reserved-memory-region" - compatibility is defined, given + region is assigned for exclusive usage for DMA transfers + +linux,default-contiguous-region: property indicating that the region + is the default region for all contiguous memory + allocations, Linux specific (optional) + +Each defined region must use unique name. It is optional to specify the +base address, so if one wants to use autoconfiguration of the base +address, he must specify the '0' as base address in the 'reg' property +and assign ann uniqe name to such regions. + + +*** Device node's properties *** + +Once the regions in the /memory/reserved-memory node are defined, they +can be assigned to device nodes to enable drivers for their special use. +The following properties are defined: + +dma-memory-region = <&phandle_to_defined_region>; + +This property indicates that the device driver should use the +memory region pointed by the given phandle. + + +*** Example *** + +This example defines a memory consisting of 4 memory banks. 3 contiguous +regions are defined for Linux kernel, one default of all device drivers +(named contig_mem, placed at 0x72000000, 64MiB), one dedicated to the +framebuffer device (labelled display_mem, placed at 0x78000000, 8MiB) +and one for multimedia processing (labelled multimedia_mem, placed at +0x77000000, 64MiB). 'display_mem' region is then assigned to fb@12300000 +device for DMA memory allocations (Linux kernel drivers will use CMA is +available or dma-exclusive usage otherwise). 'multimedia_mem' is +assigned to scaller@12500000 and codec@12600000 devices for contiguous +memory allocations when CMA driver is enabled. + +The reason for creating a separate region for framebuffer device is to +match the framebuffer base address to the one configured by bootloader, +so once Linux kernel drivers starts no glitches on the displayed boot +logo appears. Scaller and codec drivers should share the memory +allocations. + +/ { + /* ... */ + memory { + reg = <0x40000000 0x10000000 + 0x50000000 0x10000000 + 0x60000000 0x10000000 + 0x70000000 0x10000000>; + + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + + /* + * global autoconfigured region for contiguous allocations + * (used only with Contiguous Memory Allocator) + */ + contig_region@0 { + compatible = "contiguous-memory-region"; + reg = <0x0 0x4000000>; + linux,default-contiguous-region; + }; + + /* + * special region for framebuffer + */ + display_mem: region@78000000 { + compatible = "contiguous-memory-region", "reserved-memory-region"; + reg = <0x78000000 0x800000>; + }; + + /* + * special region for multimedia processing devices + */ + multimedia_mem: region@77000000 { + compatible = "contiguous-memory-region"; + reg = <0x77000000 0x4000000>; + }; + }; + }; + + /* ... */ + + fb0: fb@12300000 { + status = "okay"; + dma-memory-region = <&display_mem>; + }; + + scaller: scaller@12500000 { + status = "okay"; + dma-memory-region = <&multimedia_mem>; + }; + + codec: codec@12600000 { + status = "okay"; + dma-memory-region = <&multimedia_mem>; + }; +}; diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig index 80e5c13..a83ab43 100644 --- a/drivers/of/Kconfig +++ b/drivers/of/Kconfig @@ -80,4 +80,10 @@ config OF_MTD depends on MTD def_bool y +config OF_RESERVED_MEM + depends on CMA || (HAVE_GENERIC_DMA_COHERENT && HAVE_MEMBLOCK) + def_bool y + help + Initialization code for DMA reserved memory + endmenu # OF diff --git a/drivers/of/Makefile b/drivers/of/Makefile index 1f9c0c4..e7e3322 100644 --- a/drivers/of/Makefile +++ b/drivers/of/Makefile @@ -10,3 +10,4 @@ obj-$(CONFIG_OF_MDIO) += of_mdio.o obj-$(CONFIG_OF_PCI) += of_pci.o obj-$(CONFIG_OF_PCI_IRQ) += of_pci_irq.o obj-$(CONFIG_OF_MTD) += of_mtd.o +obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c new file mode 100644 index 0000000..d97fcdf --- /dev/null +++ b/drivers/of/of_reserved_mem.c @@ -0,0 +1,175 @@ +/* + * Device tree based initialization code for reserved memory. + * + * Copyright (c) 2013 Samsung Electronics Co., Ltd. + * http://www.samsung.com + * Author: Marek Szyprowski + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License or (at your optional) any later version of the license. + */ + +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MAX_RESERVED_REGIONS 16 +struct reserved_mem { + phys_addr_t base; + unsigned long size; + struct cma *cma; + char name[32]; +}; +static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS]; +static int reserved_mem_count; + +static int __init reserved_mem_fdt_scan(unsigned long node, const char *uname, + int depth, void *data) +{ + phys_addr_t base, size; + int is_cma, is_reserved; + unsigned long len; + void *prop; + + is_cma = of_flat_dt_is_compatible(node, "contiguous-memory-region"); + is_reserved = of_flat_dt_is_compatible(node, "reserved-memory-region"); + + if (!is_reserved && !(is_cma && IS_ENABLED(CONFIG_CMA))) + return 0; + + prop = of_get_flat_dt_prop(node, "reg", &len); + if (!prop || (len != 2 * sizeof(unsigned long))) { + pr_err("Reserved mem: node %s, incorrect \"reg\" property\n", + uname); + return 0; + } + + if (sizeof(unsigned long) == 4) { + base = be32_to_cpu(((__be32 *)prop)[0]); + size = be32_to_cpu(((__be32 *)prop)[1]); + } else { + base = be64_to_cpu(((__be64 *)prop)[0]); + size = be64_to_cpu(((__be64 *)prop)[1]); + } + + pr_info("Reserved mem: found %s, memory base %lx, size %ld MiB\n", + uname, (unsigned long)base, (unsigned long)size / SZ_1M); + + if (reserved_mem_count == ARRAY_SIZE(reserved_mem)) + return -ENOMEM; + + reserved_mem[reserved_mem_count].base = base; + reserved_mem[reserved_mem_count].size = size; + strcpy(reserved_mem[reserved_mem_count].name, uname); + + if (IS_ENABLED(CONFIG_CMA) && is_cma) { + struct cma *cma; + if (dma_contiguous_reserve_area(size, base, 0, &cma) == 0) { + reserved_mem[reserved_mem_count].cma = cma; + reserved_mem_count++; + + if (of_get_flat_dt_prop(node, + "linux,default-contiguous-region", + NULL)) + dma_contiguous_set_default_area(cma); + } + } else if (is_reserved) { + if (memblock_remove(base, size) == 0) + reserved_mem_count++; + else + pr_err("Failed to reserve memory for %s\n", uname); + } + + return 0; +} + +static struct reserved_mem *get_dma_memory_region(struct device *dev) +{ + struct device_node *node; + const char *name; + int i; + + node = of_parse_phandle(dev->of_node, "dma-memory-region", 0); + if (!node) + return NULL; + + name = kbasename(node->full_name); + for (i = 0; i < reserved_mem_count; i++) + if (strcmp(name, reserved_mem[i].name) == 0) + return &reserved_mem[i]; + return NULL; +} + +static void reserved_mem_assign_device_from_dt(struct device *dev) +{ + struct reserved_mem *region = get_dma_memory_region(dev); + if (!region) + return; + + if (region->cma) { + dma_contiguous_add_device(dev, region->cma); + pr_info("Assigned CMA %s to %s device\n", region->name, + dev_name(dev)); + } else { + if (dma_declare_coherent_memory(dev, region->base, region->base, + region->size, DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE) != 0) + pr_info("Declared reserved memory %s to %s device\n", + region->name, dev_name(dev)); + } +} + +static void reserved_mem_release_device_from_dt(struct device *dev) +{ + struct reserved_mem *region = get_dma_memory_region(dev); + if (!region) + return; + if (!region->cma) + dma_release_declared_memory(dev); +} + +static int reserved_mem_device_init_notifier_call(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct device *dev = data; + if (event == BUS_NOTIFY_ADD_DEVICE && dev->of_node) + reserved_mem_assign_device_from_dt(dev); + else if (event == BUS_NOTIFY_DEL_DEVICE && dev->of_node) + reserved_mem_release_device_from_dt(dev); + return NOTIFY_DONE; +} + +static struct notifier_block reserved_mem_dev_init_nb = { + .notifier_call = reserved_mem_device_init_notifier_call, +}; + +static int __init reserved_mem_init_reserved_areas(void) +{ + bus_register_notifier(&platform_bus_type, &reserved_mem_dev_init_nb); + return 0; +} +core_initcall(reserved_mem_init_reserved_areas); + +/** + * dma_reserved_mem_reserve() - grab memory reserved for device exclusive use + * + * This function grabs memory from early allocator for device exclusive use + * defined in device tree structures. It should be called by arch specific code + * once the early allocator (memblock) has been activated and all other + * subsystems have already allocated/reserved memory. + */ +void __init dma_reserved_mem_of_reserve(void) +{ + of_scan_flat_dt_by_path("/memory/reserved-memory", + reserved_mem_fdt_scan, NULL); +} diff --git a/include/asm-generic/dma-coherent.h b/include/asm-generic/dma-coherent.h index 2be8a2d..06111d00 100644 --- a/include/asm-generic/dma-coherent.h +++ b/include/asm-generic/dma-coherent.h @@ -32,4 +32,10 @@ dma_mark_declared_memory_occupied(struct device *dev, #define dma_mmap_from_coherent(dev, vma, vaddr, order, ret) (0) #endif +#ifdef CONFIG_OF_RESERVED_MEM +void __init dma_reserved_mem_of_reserve(void); +#else +#define dma_reserved_mem_of_reserve() +#endif + #endif