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=-13.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 40E7FC31E46 for ; Wed, 12 Jun 2019 10:49:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 163AF2082C for ; Wed, 12 Jun 2019 10:49:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=sifive.com header.i=@sifive.com header.b="SC/wtDlW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407968AbfFLKtO (ORCPT ); Wed, 12 Jun 2019 06:49:14 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:33573 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2407236AbfFLKtO (ORCPT ); Wed, 12 Jun 2019 06:49:14 -0400 Received: by mail-pf1-f195.google.com with SMTP id x15so9469883pfq.0 for ; Wed, 12 Jun 2019 03:49:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=/34VUba2TMn1HUJYz+e67ilwN8q7isgKAmoXZ4qRiqs=; b=SC/wtDlWHVohDk7cxk5knZoolyQZl4Clqn455YPX3TFOuVKH5GRuCtgk3p6HL+y8jn b+keSwdI+s29Sse4jokvis6wMRIfvVT0nh7ABPa6t1aMvDSdLkexGNnD+j9irzPHXud5 mXH820BF/AhKZIJ8f8JFX1tOayUZBgudZUu6F9jLp6An15h3NMu2RgXBMjjgrj0dzVE+ jI0yzEL+/aQu0+z0MXvYsxxXEs0Kr3/VIp5zaMWvsgVIK046vdZVePonBYmVst2ug4iH JDJCWMFbeaAou4tAl8U+yJ0W9eO5ruf4/AJYDr+Mo6IdiPCHaIm2kjWrXud2/P76YHmh KGDg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=/34VUba2TMn1HUJYz+e67ilwN8q7isgKAmoXZ4qRiqs=; b=D9EHu4Xrg1B4LElQt9zBl80F4adp8atYw4uv57WVNVvTJbogG7QK4uLmmon0QWR93Q UV7+MusLAOUC35uhJdIq+2te3K1X3kVCat/MDtXmbhW296nQ7R78f3Ajg1IhdcY04d2q 7ElMv49rdMqSvtHziRuCc8Rn1ytRmgv3xVV3qL11ncS7aqNLfoiJ+tqiLpY+K7ZHkLQO eUsnExD1JHd/rpHRLB6QMc2TJYA3DL97DuhLSOX65RNzzOAOaS7ypCD7a1UnOOAaQhH3 x5QLsaoo8sWETF5Djgvb0u6Mf1dGu2C8l7p0XrMTKxHvmK09peJd2HVubG0Xj0PbJVbK NIQw== X-Gm-Message-State: APjAAAXUrAE26ZNoaCNbR17MYNDqG+qCjb3RVc/U8GZQ8hX+XKtXa6IG 0540xHj0BNO9bzjiAwpzUT4aUg== X-Google-Smtp-Source: APXvYqyyIMxcvMkdOmgbGdxqwUCfj1i8ToNEidoIVG/3vovKkuMaa+3pJ9drMOOqrY0fD0slF0BNZg== X-Received: by 2002:a62:5c84:: with SMTP id q126mr59382546pfb.247.1560336553124; Wed, 12 Jun 2019 03:49:13 -0700 (PDT) Received: from buildserver-90.open-silicon.com ([114.143.65.226]) by smtp.googlemail.com with ESMTPSA id y22sm12241561pfm.70.2019.06.12.03.49.08 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 12 Jun 2019 03:49:12 -0700 (PDT) From: Sagar Shrikant Kadam To: marek.vasut@gmail.com, tudor.ambarus@microchip.com, dwmw2@infradead.org, computersforpeace@gmail.com, miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Cc: palmer@sifive.com, aou@eecs.berkeley.edu, paul.walmsley@sifive.com, wesley@sifive.com, Sagar Shrikant Kadam Subject: [PATCH v5 2/3] mtd: spi-nor: add support to unlock flash device Date: Wed, 12 Jun 2019 16:17:55 +0530 Message-Id: <1560336476-31763-3-git-send-email-sagar.kadam@sifive.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1560336476-31763-1-git-send-email-sagar.kadam@sifive.com> References: <1560336476-31763-1-git-send-email-sagar.kadam@sifive.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Nor device (is25wp256 mounted on HiFive unleashed Rev A00 board) from ISSI have memory blocks guarded by block protection bits BP[0,1,2,3]. Clearing block protection bits,unlocks the flash memory regions The unlock scheme is registered during nor scans. Based on code developed by Wesley Terpstra and/or Palmer Dabbelt . https://github.com/riscv/riscv-linux/commit/c94e267766d62bc9a669611c3d0c8ed5ea26569b Signed-off-by: Sagar Shrikant Kadam --- drivers/mtd/spi-nor/spi-nor.c | 51 ++++++++++++++++++++++++++++++++++++++++++- include/linux/mtd/spi-nor.h | 1 + 2 files changed, 51 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 2d5a925..b7c6261 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -1461,6 +1461,49 @@ static int macronix_quad_enable(struct spi_nor *nor) } /** + * issi_unlock() - clear BP[0123] write-protection. + * @nor: pointer to a 'struct spi_nor'. + * @ofs: offset from which to unlock memory. + * @len: number of bytes to unlock. + * + * Bits [2345] of the Status Register are BP[0123]. + * ISSI chips use a different block protection scheme than other chips. + * Just disable the write-protect unilaterally. + * + * Return: 0 on success, -errno otherwise. + */ +static int issi_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) +{ + int ret, val; + u8 mask = SR_BP0 | SR_BP1 | SR_BP2 | SR_BP3; + + val = read_sr(nor); + if (val < 0) + return val; + if (!(val & mask)) + return 0; + + write_enable(nor); + + write_sr(nor, val & ~mask); + + ret = spi_nor_wait_till_ready(nor); + if (ret) + return ret; + + ret = read_sr(nor); + if (ret > 0 && !(ret & mask)) { + dev_info(nor->dev, + "ISSI Block Protection Bits cleared SR=0x%x", ret); + ret = 0; + } else { + dev_err(nor->dev, "ISSI Block Protection Bits not cleared\n"); + ret = -EINVAL; + } + return ret; +} + +/** * spansion_quad_enable() - set QE bit in Configuraiton Register. * @nor: pointer to a 'struct spi_nor' * @@ -1836,7 +1879,7 @@ static int sr2_bit7_quad_enable(struct spi_nor *nor) SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ) }, { "is25wp256", INFO(0x9d7019, 0, 64 * 1024, 1024, SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ | - SPI_NOR_4B_OPCODES) + SPI_NOR_4B_OPCODES | SPI_NOR_HAS_LOCK) }, /* Macronix */ @@ -4080,6 +4123,12 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, nor->flash_is_locked = stm_is_locked; } + /* NOR protection support for ISSI chips */ + if (JEDEC_MFR(info) == SNOR_MFR_ISSI || + info->flags & SPI_NOR_HAS_LOCK) { + nor->flash_unlock = issi_unlock; + + } if (nor->flash_lock && nor->flash_unlock && nor->flash_is_locked) { mtd->_lock = spi_nor_lock; mtd->_unlock = spi_nor_unlock; diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index ff13297..9a7d719 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -127,6 +127,7 @@ #define SR_BP0 BIT(2) /* Block protect 0 */ #define SR_BP1 BIT(3) /* Block protect 1 */ #define SR_BP2 BIT(4) /* Block protect 2 */ +#define SR_BP3 BIT(5) /* Block protect 3 for ISSI device*/ #define SR_TB BIT(5) /* Top/Bottom protect */ #define SR_SRWD BIT(7) /* SR write protect */ /* Spansion/Cypress specific status bits */ -- 1.9.1