From patchwork Mon May 25 09:15:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pratyush Yadav X-Patchwork-Id: 11568337 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C12591392 for ; Mon, 25 May 2020 09:17:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AACA3208B6 for ; Mon, 25 May 2020 09:17:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="AE7Sq50Q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389493AbgEYJRa (ORCPT ); Mon, 25 May 2020 05:17:30 -0400 Received: from fllv0015.ext.ti.com ([198.47.19.141]:53160 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389454AbgEYJR3 (ORCPT ); Mon, 25 May 2020 05:17:29 -0400 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 04P9HEUw095689; Mon, 25 May 2020 04:17:14 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1590398234; bh=ZfUbh82N6QxYzzf9GICZYBFd0OVcUih5gJ0g44AGOsU=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=AE7Sq50Q8Zk6S0li2ZHnlTayVnuWFIlb5A88mgXqSL2oiqjSiT6Yf0cnbNcnAknEO giH2KdlqsoVzBafBmBxQaFlp+k5BQj/yWmg7YxCAKOF+rOMbirsvAAKGRTB/4P+XEx PSxVbYtCGjNri18mQ/m1VKZYvEFfgIN5tpVDZh9g= Received: from DFLE103.ent.ti.com (dfle103.ent.ti.com [10.64.6.24]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 04P9HEJw014754 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 25 May 2020 04:17:14 -0500 Received: from DFLE108.ent.ti.com (10.64.6.29) by DFLE103.ent.ti.com (10.64.6.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3; Mon, 25 May 2020 04:17:14 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE108.ent.ti.com (10.64.6.29) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3 via Frontend Transport; Mon, 25 May 2020 04:17:14 -0500 Received: from pratyush-OptiPlex-790.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 04P9FjAF034800; Mon, 25 May 2020 04:17:08 -0500 From: Pratyush Yadav To: Tudor Ambarus , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Mark Brown , Nicolas Ferre , Alexandre Belloni , Ludovic Desroches , Matthias Brugger , Michal Simek , , , , , CC: Pratyush Yadav , Sekhar Nori , Boris Brezillon , Mason Yang Subject: [PATCH v9 15/19] mtd: spi-nor: core: perform a Soft Reset on shutdown Date: Mon, 25 May 2020 14:45:40 +0530 Message-ID: <20200525091544.17270-16-p.yadav@ti.com> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200525091544.17270-1-p.yadav@ti.com> References: <20200525091544.17270-1-p.yadav@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Perform a Soft Reset on shutdown on flashes that support it so that the flash can be reset to its initial state and any configurations made by spi-nor (given that they're only done in volatile registers) will be reset. This will hand back the flash in pristine state for any further operations on it. Signed-off-by: Pratyush Yadav --- drivers/mtd/spi-nor/core.c | 42 +++++++++++++++++++++++++++++++++++++ include/linux/mtd/spi-nor.h | 2 ++ 2 files changed, 44 insertions(+) diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index a94376344be5..68559386f6f8 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -40,6 +40,9 @@ #define SPI_NOR_MAX_ADDR_WIDTH 4 +#define SPI_NOR_SRST_SLEEP_MIN 200 +#define SPI_NOR_SRST_SLEEP_MAX 400 + /** * spi_nor_get_cmd_ext() - Get the command opcode extension based on the * extension type. @@ -3201,6 +3204,41 @@ static int spi_nor_init(struct spi_nor *nor) return 0; } +static void spi_nor_soft_reset(struct spi_nor *nor) +{ + struct spi_mem_op op; + int ret; + + op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRSTEN, 8), + SPI_MEM_OP_NO_DUMMY, + SPI_MEM_OP_NO_ADDR, + SPI_MEM_OP_NO_DATA); + spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR); + ret = spi_mem_exec_op(nor->spimem, &op); + if (ret) { + dev_warn(nor->dev, "Software reset failed: %d\n", ret); + return; + } + + op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_SRST, 8), + SPI_MEM_OP_NO_DUMMY, + SPI_MEM_OP_NO_ADDR, + SPI_MEM_OP_NO_DATA); + spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR); + ret = spi_mem_exec_op(nor->spimem, &op); + if (ret) { + dev_warn(nor->dev, "Software reset failed: %d\n", ret); + return; + } + + /* + * Software Reset is not instant, and the delay varies from flash to + * flash. Looking at a few flashes, most range somewhere below 100 + * microseconds. So, sleep for a range of 200-400 us. + */ + usleep_range(SPI_NOR_SRST_SLEEP_MIN, SPI_NOR_SRST_SLEEP_MAX); +} + /* mtd resume handler */ static void spi_nor_resume(struct mtd_info *mtd) { @@ -3220,6 +3258,10 @@ void spi_nor_restore(struct spi_nor *nor) if (nor->addr_width == 4 && !(nor->flags & SNOR_F_4B_OPCODES) && nor->flags & SNOR_F_BROKEN_RESET) nor->params->set_4byte_addr_mode(nor, false); + + if (nor->info->flags & SPI_NOR_OCTAL_DTR_READ && + nor->flags & SNOR_F_SOFT_RESET) + spi_nor_soft_reset(nor); } EXPORT_SYMBOL_GPL(spi_nor_restore); diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index d251a5d02be2..06884a188315 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -51,6 +51,8 @@ #define SPINOR_OP_CLFSR 0x50 /* Clear flag status register */ #define SPINOR_OP_RDEAR 0xc8 /* Read Extended Address Register */ #define SPINOR_OP_WREAR 0xc5 /* Write Extended Address Register */ +#define SPINOR_OP_SRSTEN 0x66 /* Software Reset Enable */ +#define SPINOR_OP_SRST 0x99 /* Software Reset */ /* 4-byte address opcodes - used on Spansion and some Macronix flashes. */ #define SPINOR_OP_READ_4B 0x13 /* Read data bytes (low frequency) */