From patchwork Tue May 19 14:26:37 2020
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: Pratyush Yadav
X-Patchwork-Id: 214622
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=-9.9 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,
URIBL_BLOCKED,
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 16460C433DF
for ;
Tue, 19 May 2020 14:28:19 +0000 (UTC)
Received: from vger.kernel.org (vger.kernel.org [23.128.96.18])
by mail.kernel.org (Postfix) with ESMTP id E4A7C20878
for ;
Tue, 19 May 2020 14:28:18 +0000 (UTC)
Authentication-Results: mail.kernel.org;
dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com
header.b="wzwkFkO6"
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
id S1729278AbgESO2S (ORCPT );
Tue, 19 May 2020 10:28:18 -0400
Received: from fllv0016.ext.ti.com ([198.47.19.142]:59218 "EHLO
fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
with ESMTP id S1729057AbgESO2S (ORCPT
); Tue, 19 May 2020 10:28:18 -0400
Received: from lelv0265.itg.ti.com ([10.180.67.224])
by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 04JES3kH075360;
Tue, 19 May 2020 09:28:03 -0500
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com;
s=ti-com-17Q1; t=1589898483;
bh=ZfUbh82N6QxYzzf9GICZYBFd0OVcUih5gJ0g44AGOsU=;
h=From:To:CC:Subject:Date:In-Reply-To:References;
b=wzwkFkO6GSt+aVHpELAqfFDjKKTrIhPqxIIz8ukKSEojI64RHuUegq6Inp9vwkfvr
wiA+ojwUBtJQBE2mEeVekMnEV7RGuezf1LRJOddDdCI73Db3CjqWS+ioYobEhAReXh
ZbiTKhqoy9QiSo9l8GYfRkNWAPXAmXhF4flUc5iI=
Received: from DFLE105.ent.ti.com (dfle105.ent.ti.com [10.64.6.26])
by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 04JES3qK082704
(version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL);
Tue, 19 May 2020 09:28:03 -0500
Received: from DFLE103.ent.ti.com (10.64.6.24) by DFLE105.ent.ti.com
(10.64.6.26) with Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1979.3;
Tue, 19 May 2020 09:28:03 -0500
Received: from lelv0327.itg.ti.com (10.180.67.183) 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 via
Frontend Transport; Tue, 19 May 2020 09:28:03 -0500
Received: from pratyush-OptiPlex-790.dhcp.ti.com (ileax41-snat.itg.ti.com
[10.172.224.153])
by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 04JEQgjX008313;
Tue, 19 May 2020 09:27:58 -0500
From: Pratyush Yadav
To: Tudor Ambarus ,
Miquel Raynal ,
Richard Weinberger ,
Vignesh Raghavendra , Mark Brown ,
Nicolas Ferre ,
Alexandre Belloni ,
Ludovic Desroches ,
Matthias Brugger ,
, ,
, ,
CC: Pratyush Yadav , Sekhar Nori ,
Boris Brezillon ,
Mason Yang
Subject: [PATCH v5 15/19] mtd: spi-nor: core: perform a Soft Reset on shutdown
Date: Tue, 19 May 2020 19:56:37 +0530
Message-ID: <20200519142642.24131-16-p.yadav@ti.com>
X-Mailer: git-send-email 2.25.0
In-Reply-To: <20200519142642.24131-1-p.yadav@ti.com>
References: <20200519142642.24131-1-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) */