From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D192C2BBE2 for ; Wed, 4 Dec 2019 09:59:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 371032073B for ; Wed, 4 Dec 2019 09:59:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="djwt+pGO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727469AbfLDJ7K (ORCPT ); Wed, 4 Dec 2019 04:59:10 -0500 Received: from fllv0015.ext.ti.com ([198.47.19.141]:56138 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726632AbfLDJ7H (ORCPT ); Wed, 4 Dec 2019 04:59:07 -0500 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id xB49wK8p016153; Wed, 4 Dec 2019 03:58:20 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1575453500; bh=v67KsIUur8Si5EL8ny/4lycyDOZ3RJik9UeRRMeK4ag=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=djwt+pGOC4J8JY7tgMOZTV9H/i/nPiVLgguqp+eiic/FbY49aq+L3Vr717ZLrKZl/ TqrfTWDkmKUw9fq2IigN9mcUjl8dXUN+JK+FWUzDpNYk8wXbmQUpu8O3Eu9kxEukaH m5azC/MqMNh13JcHseLDtPbFCPJpSUF0UI6Kze7I= Received: from DFLE112.ent.ti.com (dfle112.ent.ti.com [10.64.6.33]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id xB49wKxa121196 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 4 Dec 2019 03:58:20 -0600 Received: from DFLE114.ent.ti.com (10.64.6.35) by DFLE112.ent.ti.com (10.64.6.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1847.3; Wed, 4 Dec 2019 03:58:19 -0600 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE114.ent.ti.com (10.64.6.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1847.3 via Frontend Transport; Wed, 4 Dec 2019 03:58:19 -0600 Received: from [172.24.145.136] (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id xB49wF0x112228; Wed, 4 Dec 2019 03:58:16 -0600 Subject: Re: [PATCH v5 4/4] mtd: Add driver for concatenating devices To: Miquel Raynal , Richard Weinberger , Tudor Ambarus , Rob Herring , Mark Rutland CC: , Thomas Petazzoni , , , Mark Brown , Boris Brezillon , Paul Kocialkowski , Bernhard Frauendienst References: <20191127105522.31445-1-miquel.raynal@bootlin.com> <20191127105522.31445-5-miquel.raynal@bootlin.com> From: Vignesh Raghavendra Message-ID: <690065a2-619d-3f97-30c6-5dea76896d78@ti.com> Date: Wed, 4 Dec 2019 15:28:46 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <20191127105522.31445-5-miquel.raynal@bootlin.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Miquel, On 27/11/19 4:25 pm, Miquel Raynal wrote: > Introduce a generic way to define concatenated MTD devices. This may > be very useful in the case of ie. stacked SPI-NOR. Partitions to > concatenate are described in an additional property of the partitions > subnode: > > flash0 { > partitions { > compatible = "fixed-partitions"; > part-concat = <&flash0_part1>, <&flash1_part0>; > > part0@0 { > label = "part0_0"; > reg = <0x0 0x800000>; > }; > > flash0_part1: part1@800000 { > label = "part0_1"; > reg = <0x800000 0x800000>; > }; > }; > }; IIUC flash0 and flash1 are subnodes of a SPI master node? And I believe flash0 node's compatible is "jedec,spi-nor"? > > flash1 { > partitions { > compatible = "fixed-partitions"; > > flash0_part1: part1@0 { s/flash0_part1/flash1_part0? > label = "part1_0"; > reg = <0x0 0x800000>; > }; > > part0@800000 { > label = "part1_1"; > reg = <0x800000 0x800000>; > }; > }; > }; > For my understanding, how many /dev/mtdX entries would this create? Regards Vignesh > This is useful for boards where memory range has been extended with > the use of multiple flash chips as memory banks of a single MTD > device, with partitions spanning chip borders. > > Suggested-by: Bernhard Frauendienst > Signed-off-by: Miquel Raynal > --- > drivers/mtd/Kconfig | 8 ++ > drivers/mtd/Makefile | 1 + > drivers/mtd/mtd_virt_concat.c | 240 ++++++++++++++++++++++++++++++++++ > 3 files changed, 249 insertions(+) > create mode 100644 drivers/mtd/mtd_virt_concat.c > > diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig > index 79a8ff542883..3e1e55e7158f 100644 > --- a/drivers/mtd/Kconfig > +++ b/drivers/mtd/Kconfig > @@ -276,6 +276,14 @@ config MTD_PARTITIONED_MASTER > the parent of the partition device be the master device, rather than > what lies behind the master. > > +config MTD_VIRT_CONCAT > + tristate "Virtual concatenated MTD devices" > + help > + This driver allows creation of a virtual MTD device, which > + concatenates multiple physical MTD devices into a single one. > + This is useful to create partitions bigger than the underlying > + physical chips by allowing cross-chip boundaries. > + > source "drivers/mtd/chips/Kconfig" > > source "drivers/mtd/maps/Kconfig" > diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile > index 58fc327a5276..c7ee13368a66 100644 > --- a/drivers/mtd/Makefile > +++ b/drivers/mtd/Makefile > @@ -27,6 +27,7 @@ obj-$(CONFIG_SSFDC) += ssfdc.o > obj-$(CONFIG_SM_FTL) += sm_ftl.o > obj-$(CONFIG_MTD_OOPS) += mtdoops.o > obj-$(CONFIG_MTD_SWAP) += mtdswap.o > +obj-$(CONFIG_MTD_VIRT_CONCAT) += mtd_virt_concat.o > > nftl-objs := nftlcore.o nftlmount.o > inftl-objs := inftlcore.o inftlmount.o > diff --git a/drivers/mtd/mtd_virt_concat.c b/drivers/mtd/mtd_virt_concat.c > new file mode 100644 > index 000000000000..23c7170ac32f > --- /dev/null > +++ b/drivers/mtd/mtd_virt_concat.c > @@ -0,0 +1,240 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Virtual concat MTD device driver > + * > + * Copyright (C) 2018 Bernhard Frauendienst > + * Author: Bernhard Frauendienst > + */ > + > +#include > +#include > +#include > +#include > +#include "mtdcore.h" > +#include > +#include > +#include > +#include > + > +#define CONCAT_PROP "part-concat" > +#define MIN_DEV_PER_CONCAT 2 > + > +/** > + * struct mtd_virt_concat - concatenation container > + * @vmtd: Virtual mtd_concat device > + * @count: Number of physical underlaying devices in @devices > + * @devices: Array of the physical devices used > + */ > +struct mtd_virt_concat { > + struct mtd_info *vmtd; > + unsigned int count; > + struct mtd_info **devices; > +}; > + > +/** > + * struct mtd_virt_concat_node - components of a concatenation > + * @head: List handle > + * @count: Number of nodes > + * @nodes: Pointer to the nodes (partitions) to concatenate > + * @concat: Concatenation container > + */ > +struct mtd_virt_concat_node { > + struct list_head head; > + unsigned int count; > + struct device_node **nodes; > + struct mtd_virt_concat *concat; > +}; > + > +static LIST_HEAD(concat_list); > + > +static void mtd_virt_concat_put_mtd_devices(struct mtd_virt_concat *concat) > +{ > + int i; > + > + for (i = 0; i < concat->count; i++) > + put_mtd_device(concat->devices[i]); > +} > + > +static int mtd_virt_concat_create_join(struct mtd_virt_concat_node *item) > +{ > + struct mtd_virt_concat *concat; > + struct mtd_info *mtd; > + ssize_t name_sz; > + char *name; > + int ret, i; > + > + concat = kzalloc(sizeof(*concat), GFP_KERNEL); > + if (!concat) > + return -ENOMEM; > + > + concat->devices = kcalloc(item->count, > + sizeof(*concat->devices), > + GFP_KERNEL); > + if (!concat->devices) { > + ret = -ENOMEM; > + goto free_concat; > + } > + > + /* Aggregate the physical devices */ > + for (i = 0; i < item->count; i++) { > + mtd = get_mtd_device_by_node(item->nodes[i]); > + if (IS_ERR(mtd)) { > + ret = PTR_ERR(mtd); > + goto put_mtd_devices; > + } > + > + concat->devices[concat->count++] = mtd; > + } > + > + /* Create the virtual device */ > + name_sz = snprintf(NULL, 0, "%s-%s%s-concat", > + concat->devices[0]->name, > + concat->devices[1]->name, > + concat->count > 2 ? "-+" : ""); > + name = kmalloc(name_sz, GFP_KERNEL); > + if (!name) { > + ret = -ENOMEM; > + goto put_mtd_devices; > + } > + > + sprintf(name, "%s-%s%s-concat", > + concat->devices[0]->name, > + concat->devices[1]->name, > + concat->count > 2 ? "-+" : ""); > + > + concat->vmtd = mtd_concat_create(concat->devices, concat->count, name); > + if (!concat->vmtd) { > + ret = -ENXIO; > + goto free_name; > + } > + > + /* Arbitrary set the first device as parent */ > + concat->vmtd->dev.parent = &concat->devices[0]->dev; > + > + /* Register the platform device */ > + ret = mtd_device_register(concat->vmtd, NULL, 0); > + if (ret) > + goto destroy_concat; > + > + item->concat = concat; > + > + return 0; > + > +destroy_concat: > + mtd_concat_destroy(concat->vmtd); > +free_name: > + kfree(name); > +put_mtd_devices: > + mtd_virt_concat_put_mtd_devices(concat); > +free_concat: > + kfree(concat); > + > + return ret; > +} > + > +static void mtd_virt_concat_destroy_joins(void) > +{ > + struct mtd_virt_concat_node *item, *tmp; > + > + list_for_each_entry_safe(item, tmp, &concat_list, head) { > + if (item->concat) { > + mtd_device_unregister(item->concat->vmtd); > + kfree(item->concat->vmtd->name); > + mtd_concat_destroy(item->concat->vmtd); > + mtd_virt_concat_put_mtd_devices(item->concat); > + } > + } > +} > + > +static int mtd_virt_concat_create_item(struct device_node *parts, > + unsigned int count) > +{ > + struct mtd_virt_concat_node *item; > + int i; > + > + item = kzalloc(sizeof(*item), GFP_KERNEL); > + if (!item) > + return -ENOMEM; > + > + item->count = count; > + item->nodes = kcalloc(count, sizeof(*item->nodes), GFP_KERNEL); > + if (!item->nodes) { > + kfree(item); > + return -ENOMEM; > + } > + > + for (i = 0; i < count; i++) > + item->nodes[i] = of_parse_phandle(parts, CONCAT_PROP, i); > + > + list_add_tail(&item->head, &concat_list); > + > + return 0; > +} > + > +static void mtd_virt_concat_destroy_items(void) > +{ > + struct mtd_virt_concat_node *item, *temp; > + int i; > + > + list_for_each_entry_safe(item, temp, &concat_list, head) { > + for (i = 0; i < item->count; i++) > + of_node_put(item->nodes[i]); > + > + kfree(item->nodes); > + kfree(item); > + } > +} > + > +static int __init mtd_virt_concat_init(void) > +{ > + struct mtd_virt_concat_node *item; > + struct device_node *parts = NULL; > + int ret = 0, count; > + > + /* List all the concatenations found in DT */ > + do { > + parts = of_find_node_with_property(parts, CONCAT_PROP); > + if (!of_device_is_available(parts)) > + continue; > + > + count = of_count_phandle_with_args(parts, CONCAT_PROP, NULL); > + if (count < MIN_DEV_PER_CONCAT) > + continue; > + > + ret = mtd_virt_concat_create_item(parts, count); > + if (ret) { > + of_node_put(parts); > + goto destroy_items; > + } > + } while (parts); > + > + /* TODO: also parse the cmdline */ > + > + /* Create the concatenations */ > + list_for_each_entry(item, &concat_list, head) { > + ret = mtd_virt_concat_create_join(item); > + if (ret) > + goto destroy_joins; > + } > + > + return 0; > + > +destroy_joins: > + mtd_virt_concat_destroy_joins(); > +destroy_items: > + mtd_virt_concat_destroy_items(); > + > + return ret; > +} > +late_initcall(mtd_virt_concat_init); > + > +static void __exit mtd_virt_concat_exit(void) > +{ > + mtd_virt_concat_destroy_joins(); > + mtd_virt_concat_destroy_items(); > +} > +module_exit(mtd_virt_concat_exit); > + > +MODULE_LICENSE("GPL v2"); > +MODULE_AUTHOR("Bernhard Frauendienst "); > +MODULE_DESCRIPTION("Virtual concat MTD device driver"); > -- Regards Vignesh