From patchwork Thu Mar 11 19:12:11 2021
Content-Type: text/plain; charset="utf-8"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
X-Patchwork-Submitter: Pratyush Yadav
X-Patchwork-Id: 12132555
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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH,
DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,
INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,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 2B940C4332E
for ; Thu, 11 Mar 2021 19:13:28 +0000 (UTC)
Received: from vger.kernel.org (vger.kernel.org [23.128.96.18])
by mail.kernel.org (Postfix) with ESMTP id E004664EFE
for ; Thu, 11 Mar 2021 19:13:27 +0000 (UTC)
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
id S229809AbhCKTMw (ORCPT );
Thu, 11 Mar 2021 14:12:52 -0500
Received: from fllv0016.ext.ti.com ([198.47.19.142]:44248 "EHLO
fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
with ESMTP id S229490AbhCKTMq (ORCPT
); Thu, 11 Mar 2021 14:12:46 -0500
Received: from lelv0265.itg.ti.com ([10.180.67.224])
by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 12BJCR4m072855;
Thu, 11 Mar 2021 13:12:27 -0600
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com;
s=ti-com-17Q1; t=1615489947;
bh=TFMbG/HskxSKnHoLH+CdmpXxIxc/DBKy8fugLnBgIIQ=;
h=From:To:CC:Subject:Date:In-Reply-To:References;
b=E+B4oiStGriEF7CnmhCLKl4uVexnuAYuBP7aDkkQqhdRG6jso4Mr3ZEurqVwyHFiL
lOViZaAKaRcUmjN+ZT1nB0QOKE5F3L8ZaM9Nx074O2kYxalzXFHnNcyMEMkJi1oBD8
Zyi6ScQdJ2/mOOgI96rf6NR0I+j7kh1SxSTqcOmg=
Received: from DLEE114.ent.ti.com (dlee114.ent.ti.com [157.170.170.25])
by lelv0265.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 12BJCQaS110401
(version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL);
Thu, 11 Mar 2021 13:12:26 -0600
Received: from DLEE103.ent.ti.com (157.170.170.33) by DLEE114.ent.ti.com
(157.170.170.25) with Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 11
Mar 2021 13:12:26 -0600
Received: from fllv0039.itg.ti.com (10.64.41.19) by DLEE103.ent.ti.com
(157.170.170.33) with Microsoft SMTP Server (version=TLS1_2,
cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via
Frontend Transport; Thu, 11 Mar 2021 13:12:26 -0600
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 12BJCHvS080816;
Thu, 11 Mar 2021 13:12:22 -0600
From: Pratyush Yadav
To: Nishanth Menon , Tero Kristo ,
Rob Herring ,
Tudor Ambarus ,
Michael Walle ,
Miquel Raynal ,
Richard Weinberger ,
Vignesh Raghavendra ,
Mark Brown ,
,
, ,
,
CC: Pratyush Yadav , Lokesh Vutla
Subject: [RFC PATCH 1/6] spi: spi-mem: Tell controller when device is ready
for calibration
Date: Fri, 12 Mar 2021 00:42:11 +0530
Message-ID: <20210311191216.7363-2-p.yadav@ti.com>
X-Mailer: git-send-email 2.30.0
In-Reply-To: <20210311191216.7363-1-p.yadav@ti.com>
References: <20210311191216.7363-1-p.yadav@ti.com>
MIME-Version: 1.0
X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180
Precedence: bulk
List-ID:
X-Mailing-List: linux-spi@vger.kernel.org
Some controllers like the Cadence OSPI controller need to perform a
calibration sequence to operate at high clock speeds. This calibration
should happen after the flash is fully initialized otherwise the
calibration might happen in a different SPI mode from the one the flash
is finally set to. Add a hook that can be used to tell the controller
when the flash is ready for calibration. Whether calibration is needed
depends on the controller.
Signed-off-by: Pratyush Yadav
---
drivers/spi/spi-mem.c | 12 ++++++++++++
include/linux/spi/spi-mem.h | 8 ++++++++
2 files changed, 20 insertions(+)
diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index dc713b0c3c4d..e2f05ad3f4dc 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -464,6 +464,18 @@ int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
}
EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
+int spi_mem_do_calibration(struct spi_mem *mem, struct spi_mem_op *op)
+{
+ struct spi_controller *ctlr = mem->spi->controller;
+
+ if (!ctlr->mem_ops || !ctlr->mem_ops->do_calibration)
+ return -EOPNOTSUPP;
+
+ ctlr->mem_ops->do_calibration(mem, op);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(spi_mem_do_calibration);
+
static ssize_t spi_mem_no_dirmap_read(struct spi_mem_dirmap_desc *desc,
u64 offs, size_t len, void *buf)
{
diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h
index 2b65c9edc34e..97a2d280f2d0 100644
--- a/include/linux/spi/spi-mem.h
+++ b/include/linux/spi/spi-mem.h
@@ -250,6 +250,12 @@ static inline void *spi_mem_get_drvdata(struct spi_mem *mem)
* the currently mapped area), and the caller of
* spi_mem_dirmap_write() is responsible for calling it again in
* this case.
+ * @do_calibration: perform calibration needed for high SPI clock speed
+ * operation. Should be called after the SPI memory device has
+ * been completely initialized. The op passed should contain
+ * a template for the read operation used for the device so
+ * the controller can decide what type of calibration is
+ * required for this type of read.
*
* This interface should be implemented by SPI controllers providing an
* high-level interface to execute SPI memory operation, which is usually the
@@ -274,6 +280,7 @@ struct spi_controller_mem_ops {
u64 offs, size_t len, void *buf);
ssize_t (*dirmap_write)(struct spi_mem_dirmap_desc *desc,
u64 offs, size_t len, const void *buf);
+ void (*do_calibration)(struct spi_mem *mem, struct spi_mem_op *op);
};
/**
@@ -346,6 +353,7 @@ bool spi_mem_dtr_supports_op(struct spi_mem *mem,
#endif /* CONFIG_SPI_MEM */
int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op);
+int spi_mem_do_calibration(struct spi_mem *mem, struct spi_mem_op *op);
bool spi_mem_supports_op(struct spi_mem *mem,
const struct spi_mem_op *op);