From patchwork Fri Dec 13 02:27:17 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergey Yanovich X-Patchwork-Id: 3337701 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 2584C9F2A9 for ; Fri, 13 Dec 2013 04:42:51 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 04FED207EF for ; Fri, 13 Dec 2013 04:42:50 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 983B6207E4 for ; Fri, 13 Dec 2013 04:42:48 +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 1VrIXW-0003B7-EU; Fri, 13 Dec 2013 02:31:43 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VrIWr-0000RS-Nk; Fri, 13 Dec 2013 02:31:01 +0000 Received: from mail-la0-x22e.google.com ([2a00:1450:4010:c03::22e]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VrIVu-0000FW-8I; Fri, 13 Dec 2013 02:30:17 +0000 Received: by mail-la0-f46.google.com with SMTP id eh20so947467lab.19 for ; Thu, 12 Dec 2013 18:29:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=TiBI8VuN53nfqZID2Sjqt0DkzihvGufidsMjyq23Nko=; b=LeRR33VkRv6tod+DbNjmD1aGDSJuLGbM6FpMtNzl/EraNm1gqiVijKlZRmYcL7wId6 wEcfQP8rxZmfsCb55KLqjcj47u8jSHTo7TKqBVlnx0LlbHkYE2ssjVVnPnRdoHZ++sly BT/ok/6zV3z5NoNc64MLy0QcHPofhQ/IJMjfPJwLWIbgSKMyIAAA3Y5NCMOniicayb2E 8yAAHNXWRNYpEaXh9TQkWY7wPVoPlhvny4hiZfVnVhgE2pcclQ0viLVFFzZyjkAIm0zo NHk5acp9Sl4Pi5G2lwsjhWYfB9DD+wb/6vY0dafWMykGH+ucA3pbhI6J5+Al4GieYroG KgOA== X-Received: by 10.152.22.201 with SMTP id g9mr25835laf.27.1386901779660; Thu, 12 Dec 2013 18:29:39 -0800 (PST) Received: from host5.omatika.ru (0893675324.static.corbina.ru. [95.31.1.192]) by mx.google.com with ESMTPSA id e10sm809634laa.6.2013.12.12.18.29.38 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 12 Dec 2013 18:29:38 -0800 (PST) From: Sergei Ianovich To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 08/16] mtd: support BB SRAM on ICP DAS LP-8x4x Date: Fri, 13 Dec 2013 06:27:17 +0400 Message-Id: <1386901645-28895-9-git-send-email-ynvich@gmail.com> X-Mailer: git-send-email 1.8.4.3 In-Reply-To: <1386901645-28895-1-git-send-email-ynvich@gmail.com> References: <1386543229-1542-1-git-send-email-ynvich@gmail.com> <1386901645-28895-1-git-send-email-ynvich@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131212_213002_693183_1DA99737 X-CRM114-Status: GOOD ( 24.15 ) X-Spam-Score: -1.9 (-) Cc: Mark Rutland , "open list:OPEN FIRMWARE AND..." , Randy Dunlap , Russell King , Kees Cook , Pawel Moll , Ian Campbell , Artem Bityutskiy , Robert Jarzmik , Stephen Warren , Rob Herring , Sergei Ianovich , Philip Avinash , Grant Likely , "open list:MEMORY TECHNOLOGY..." , David Woodhouse 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=-3.9 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, RCVD_IN_SBL, RP_MATCHES_RCVD, T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=no 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 This provides an MTD device driver for 512kB of battery backed up SRAM on ICPDAS LP-8X4X programmable automation controllers. SRAM chip is connected via FPGA and is not accessible without a driver, unlike flash memory which is wired to CPU MMU. This SRAM becomes an excellent persisent storage of volatile process data like counter values and sensor statuses. Storing those data in flash or mmc card is not a viable solution. Signed-off-by: Sergei Ianovich --- v0..v2 * use device tree * use devm helpers where possible arch/arm/boot/dts/pxa27x-lp8x4x.dts | 6 + arch/arm/configs/lp8x4x_defconfig | 1 + drivers/mtd/devices/Kconfig | 14 +++ drivers/mtd/devices/Makefile | 1 + drivers/mtd/devices/sram_lp8x4x.c | 227 ++++++++++++++++++++++++++++++++++++ 5 files changed, 249 insertions(+) create mode 100644 drivers/mtd/devices/sram_lp8x4x.c diff --git a/arch/arm/boot/dts/pxa27x-lp8x4x.dts b/arch/arm/boot/dts/pxa27x-lp8x4x.dts index 574e853..b7f8cfc 100644 --- a/arch/arm/boot/dts/pxa27x-lp8x4x.dts +++ b/arch/arm/boot/dts/pxa27x-lp8x4x.dts @@ -59,6 +59,12 @@ device-width = <1>; }; + sram@1700a000 { + compatible = "icpdas,sram-lp8x4x"; + reg = <0x1700a000 0x1000 + 0x1700901e 0x1>; + }; + pxabus { pxairq: interrupt-controller@40d00000 { marvell,intc-priority; diff --git a/arch/arm/configs/lp8x4x_defconfig b/arch/arm/configs/lp8x4x_defconfig index 57f2830..8fa871e 100644 --- a/arch/arm/configs/lp8x4x_defconfig +++ b/arch/arm/configs/lp8x4x_defconfig @@ -57,6 +57,7 @@ CONFIG_MTD_CFI_ADV_OPTIONS=y CONFIG_MTD_CFI_GEOMETRY=y CONFIG_MTD_CFI_INTELEXT=y CONFIG_MTD_PHYSMAP_OF=y +CONFIG_MTD_SRAM_LP8X4X=y CONFIG_PROC_DEVICETREE=y CONFIG_BLK_DEV_LOOP=y CONFIG_BLK_DEV_LOOP_MIN_COUNT=2 diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig index 0128138..95f2075 100644 --- a/drivers/mtd/devices/Kconfig +++ b/drivers/mtd/devices/Kconfig @@ -217,4 +217,18 @@ config BCH_CONST_T default 4 endif +config MTD_SRAM_LP8X4X + tristate "SRAM on ICPDAS LP-8X4X" + depends on OF && ARCH_PXA + ---help--- + This provides an MTD device driver for 512kiB of battery backed up SRAM + on ICPDAS LP-8X4X programmable automation controllers. + + SRAM chip is connected via FPGA and is not accessible without a driver, + unlike flash memory which is wired to CPU MMU. + + Say N, unless you plan to run this kernel on LP-8X4X. + + If you say M, the module will be called sram_lp8x4x. + endmenu diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile index d83bd73..56a74c9 100644 --- a/drivers/mtd/devices/Makefile +++ b/drivers/mtd/devices/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_MTD_NAND_OMAP_BCH) += elm.o obj-$(CONFIG_MTD_SPEAR_SMI) += spear_smi.o obj-$(CONFIG_MTD_SST25L) += sst25l.o obj-$(CONFIG_MTD_BCM47XXSFLASH) += bcm47xxsflash.o +obj-$(CONFIG_MTD_SRAM_LP8X4X) += sram_lp8x4x.o CFLAGS_docg3.o += -I$(src) diff --git a/drivers/mtd/devices/sram_lp8x4x.c b/drivers/mtd/devices/sram_lp8x4x.c new file mode 100644 index 0000000..9dc7149 --- /dev/null +++ b/drivers/mtd/devices/sram_lp8x4x.c @@ -0,0 +1,227 @@ +/* + * linux/drivers/mtd/devices/lp8x4x_sram.c + * + * MTD Driver for SRAM on ICPDAS LP-8x4x + * Copyright (C) 2013 Sergei Ianovich + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation or any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +struct lp8x4x_sram_info { + void __iomem *bank; + void __iomem *virt; + struct mutex lock; + unsigned active_bank; + struct mtd_info mtd; +}; + +static int +lp8x4x_sram_erase(struct mtd_info *mtd, struct erase_info *instr) +{ + struct lp8x4x_sram_info *info = mtd->priv; + unsigned bank = instr->addr >> 11; + unsigned offset = (instr->addr & 0x7ff) << 1; + loff_t i; + + mutex_lock(&info->lock); + if (unlikely(bank != info->active_bank)) { + info->active_bank = bank; + iowrite8(bank, info->bank); + } + for (i = 0; i < instr->len; i++) { + iowrite8(0xff, info->virt + offset); + offset += 2; + if (unlikely(offset == 0)) { + info->active_bank++; + iowrite8(info->active_bank, info->bank); + } + } + mutex_unlock(&info->lock); + instr->state = MTD_ERASE_DONE; + mtd_erase_callback(instr); + + return 0; +} + +static int +lp8x4x_sram_write(struct mtd_info *mtd, loff_t to, size_t len, + size_t *retlen, const u_char *b) +{ + struct lp8x4x_sram_info *info = mtd->priv; + unsigned bank = to >> 11; + unsigned offset = (to & 0x7ff) << 1; + loff_t i; + + mutex_lock(&info->lock); + if (unlikely(bank != info->active_bank)) { + info->active_bank = bank; + iowrite8(bank, info->bank); + } + for (i = 0; i < len; i++) { + iowrite8(b[i], info->virt + offset); + offset += 2; + if (unlikely(offset == 0)) { + info->active_bank++; + iowrite8(info->active_bank, info->bank); + } + } + mutex_unlock(&info->lock); + *retlen = len; + return 0; +} + +static int +lp8x4x_sram_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *b) +{ + struct lp8x4x_sram_info *info = mtd->priv; + unsigned bank = from >> 11; + unsigned offset = (from & 0x7ff) << 1; + loff_t i; + + mutex_lock(&info->lock); + if (unlikely(bank != info->active_bank)) { + info->active_bank = bank; + iowrite8(bank, info->bank); + } + for (i = 0; i < len; i++) { + b[i] = ioread8(info->virt + offset); + offset += 2; + if (unlikely(offset == 0)) { + info->active_bank++; + iowrite8(info->active_bank, info->bank); + } + } + mutex_unlock(&info->lock); + *retlen = len; + return 0; +} + +static void +lp8x4x_sram_sync(struct mtd_info *mtd) +{ +} + +static struct of_device_id of_flash_match[] = { + { + .compatible = "icpdas,sram-lp8x4x", + }, + { }, +}; +MODULE_DEVICE_TABLE(of, of_flash_match); + +static const char * const probe_types[] = { + "cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL }; + +static int +lp8x4x_sram_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct lp8x4x_sram_info *info; + struct resource *r1, *r2; + char sz_str[16]; + struct mtd_part_parser_data ppdata; + int err = 0; + + match = of_match_device(of_flash_match, &pdev->dev); + if (!match) + return -EINVAL; + + r1 = platform_get_resource(pdev, IORESOURCE_MEM, 0); + r2 = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!r1 || !r2) + return -ENODEV; + + info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->virt = devm_ioremap_resource(&pdev->dev, r1); + if (!info->virt) { + dev_err(&pdev->dev, "Failed to ioremap %p\n", + info->virt); + return -EFAULT; + } + + info->bank = devm_ioremap_resource(&pdev->dev, r2); + if (!info->bank) { + dev_err(&pdev->dev, "Failed to ioremap %p\n", + info->bank); + return -EFAULT; + } + + info->mtd.priv = info; + info->mtd.name = "SRAM"; + info->mtd.type = MTD_RAM; + info->mtd.flags = MTD_CAP_RAM; + info->mtd.size = resource_size(r1) << 7; + info->mtd.erasesize = 512; + info->mtd.writesize = 4; + info->mtd._erase = lp8x4x_sram_erase; + info->mtd._write = lp8x4x_sram_write; + info->mtd._read = lp8x4x_sram_read; + info->mtd._sync = lp8x4x_sram_sync; + info->mtd.owner = THIS_MODULE; + + mutex_init(&info->lock); + iowrite8(info->active_bank, info->bank); + platform_set_drvdata(pdev, info); + + ppdata.of_node = pdev->dev.of_node; + err = mtd_device_parse_register(&info->mtd, probe_types, &ppdata, + NULL, 0); + + if (err < 0) { + dev_err(&pdev->dev, "Failed to register platform device\n"); + return err; + } + + string_get_size(info->mtd.size, STRING_UNITS_2, sz_str, + sizeof(sz_str)); + dev_info(&pdev->dev, "using %s SRAM on LP-8X4X as %s\n", sz_str, + dev_name(&info->mtd.dev)); + return 0; +} + +static int +lp8x4x_sram_remove(struct platform_device *dev) +{ + struct lp8x4x_sram_info *info = platform_get_drvdata(dev); + + mtd_device_unregister(&info->mtd); + platform_set_drvdata(dev, NULL); + return 0; +} + +static struct platform_driver lp8x4x_sram_driver = { + .driver = { + .name = "sram-lp8x4x", + .owner = THIS_MODULE, + .of_match_table = of_flash_match, + }, + .probe = lp8x4x_sram_probe, + .remove = lp8x4x_sram_remove, +}; + +module_platform_driver(lp8x4x_sram_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sergei Ianovich "); +MODULE_DESCRIPTION("MTD driver for SRAM on ICPDAS LP-8x4x");