From patchwork Tue May 18 13:43:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Patrice CHOTARD X-Patchwork-Id: 12264837 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,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 B93E1C433ED for ; Tue, 18 May 2021 13:43:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9EE1B6105A for ; Tue, 18 May 2021 13:43:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233399AbhERNpL (ORCPT ); Tue, 18 May 2021 09:45:11 -0400 Received: from mx07-00178001.pphosted.com ([185.132.182.106]:58132 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232892AbhERNpG (ORCPT ); Tue, 18 May 2021 09:45:06 -0400 Received: from pps.filterd (m0241204.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 14IDVsZP032069; Tue, 18 May 2021 15:43:35 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=selector1; bh=JhJOQaZYOu9SBDfIyko93UVT6vHk1CgTqiJU4mwALvc=; b=wP3A/s5k0pB3uXNjLLSHnnqRuroKmkXjc4MbRsyZkY7JKxv3RIR8gdNUE1//NBqAsP16 aKAW0HhpDec256rC/SsutzQ2j4CZ9jZ7hneui/0R+Z3te0AcDY5JZfSU/KrpOxvbL5mp MMGK5xYGNpezo7oEKLS3nLAoIHPlfBD2SjjWGNvP7yN0QfxxjFSx7q4PSBZUHEXwQetK o85uB/rrd2hCkcw1lCZ5UvDEZF4wGC+XFuc1jXh/9F3f4ImG5A80S69Gx/GDm+B3OFJ9 f+aFggvpZOJGEUQA/VqcJQ9NydkCu1Q4JrU16b8hfhRJPrHUYgo41Rw+KWalV1a1nJ+r Cg== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 38m4673mpn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 18 May 2021 15:43:35 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id E78A3100034; Tue, 18 May 2021 15:43:34 +0200 (CEST) Received: from Webmail-eu.st.com (sfhdag2node3.st.com [10.75.127.6]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id CF738227D8B; Tue, 18 May 2021 15:43:34 +0200 (CEST) Received: from localhost (10.75.127.49) by SFHDAG2NODE3.st.com (10.75.127.6) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 18 May 2021 15:43:34 +0200 From: To: Mark Brown , Miquel Raynal , Vignesh Raghavendra , Boris Brezillon , , Alexandre Torgue , , , , CC: , Subject: [PATCH v4 1/3] spi: spi-mem: add automatic poll status functions Date: Tue, 18 May 2021 15:43:30 +0200 Message-ID: <20210518134332.17826-2-patrice.chotard@foss.st.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210518134332.17826-1-patrice.chotard@foss.st.com> References: <20210518134332.17826-1-patrice.chotard@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.49] X-ClientProxiedBy: SFHDAG2NODE1.st.com (10.75.127.4) To SFHDAG2NODE3.st.com (10.75.127.6) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.761 definitions=2021-05-18_04:2021-05-18,2021-05-18 signatures=0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org From: Patrice Chotard With STM32 QSPI, it is possible to poll the status register of the device. This could be done to offload the CPU during an operation (erase or program a SPI NAND for example). spi_mem_poll_status API has been added to handle this feature. This new function take care of the offload/non-offload cases. For the non-offload case, use read_poll_timeout() to poll the status in order to release CPU during this phase. For example, previously, when erasing large area, in non-offload case, CPU load can reach ~50%, now it decrease to ~35%. Signed-off-by: Patrice Chotard Signed-off-by: Christophe Kerello Reviewed-by: Boris Brezillon --- Changes in v4: - Remove init_completion() from spi_mem_probe() added in v2. - Add missing static for spi_mem_read_status(). - Check if operation in spi_mem_poll_status() is a READ. Changes in v3: - Add spi_mem_read_status() which allows to read 8 or 16 bits status. - Add initial_delay_us and polling_delay_us parameters to spi_mem_poll_status() and also to poll_status() callback. - Move spi_mem_supports_op() in SW-based polling case. - Add delay before invoking read_poll_timeout(). - Remove the reinit/wait_for_completion() added in v2. Changes in v2: - Indicates the spi_mem_poll_status() timeout unit - Use 2-byte wide status register - Add spi_mem_supports_op() call in spi_mem_poll_status() - Add completion management in spi_mem_poll_status() - Add offload/non-offload case management in spi_mem_poll_status() - Optimize the non-offload case by using read_poll_timeout() drivers/spi/spi-mem.c | 85 +++++++++++++++++++++++++++++++++++++ include/linux/spi/spi-mem.h | 14 ++++++ 2 files changed, 99 insertions(+) diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 1513553e4080..97c7a83686c7 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -6,6 +6,7 @@ * Author: Boris Brezillon */ #include +#include #include #include #include @@ -743,6 +744,90 @@ static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv) return container_of(drv, struct spi_mem_driver, spidrv.driver); } +static int spi_mem_read_status(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 *status) +{ + const u8 *bytes = (u8 *)op->data.buf.in; + int ret; + + ret = spi_mem_exec_op(mem, op); + if (ret) + return ret; + + if (op->data.nbytes > 1) + *status = ((u16)bytes[0] << 8) | bytes[1]; + else + *status = bytes[0]; + + return 0; +} + +/** + * spi_mem_poll_status() - Poll memory device status + * @mem: SPI memory device + * @op: the memory operation to execute + * @mask: status bitmask to ckeck + * @match: (status & mask) expected value + * @initial_delay_us: delay in us before starting to poll + * @polling_delay_us: time to sleep between reads in us + * @timeout_ms: timeout in milliseconds + * + * This function send a polling status request to the controller driver + * + * Return: 0 in case of success, -ETIMEDOUT in case of error, + * -EOPNOTSUPP if not supported. + */ +int spi_mem_poll_status(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 mask, u16 match, + unsigned long initial_delay_us, + unsigned long polling_delay_us, + u16 timeout_ms) +{ + struct spi_controller *ctlr = mem->spi->controller; + int ret = -EOPNOTSUPP; + int read_status_ret; + u16 status; + + if (op->data.nbytes < 1 || op->data.nbytes > 2 || + op->data.dir != SPI_MEM_DATA_IN) + return (-EINVAL); + + if (ctlr->mem_ops && ctlr->mem_ops->poll_status) { + ret = spi_mem_access_start(mem); + if (ret) + return ret; + + ret = ctlr->mem_ops->poll_status(mem, op, mask, match, + initial_delay_us, polling_delay_us, + timeout_ms); + + spi_mem_access_end(mem); + } + + if (ret == -EOPNOTSUPP) { + if (!spi_mem_supports_op(mem, op)) + return ret; + + if (initial_delay_us < 10) + udelay(initial_delay_us); + else + usleep_range((initial_delay_us >> 2) + 1, + initial_delay_us); + + ret = read_poll_timeout(spi_mem_read_status, read_status_ret, + (read_status_ret || ((status) & mask) == match), + polling_delay_us, timeout_ms * 1000, false, mem, + op, &status); + if (read_status_ret) + return read_status_ret; + } + + return ret; +} +EXPORT_SYMBOL_GPL(spi_mem_poll_status); + static int spi_mem_probe(struct spi_device *spi) { struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver); diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h index 2b65c9edc34e..10375d9ad747 100644 --- a/include/linux/spi/spi-mem.h +++ b/include/linux/spi/spi-mem.h @@ -250,6 +250,7 @@ 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. + * @poll_status: poll memory device status * * This interface should be implemented by SPI controllers providing an * high-level interface to execute SPI memory operation, which is usually the @@ -274,6 +275,12 @@ 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); + int (*poll_status)(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 mask, u16 match, + unsigned long initial_delay_us, + unsigned long polling_rate_us, + unsigned long timeout_ms); }; /** @@ -369,6 +376,13 @@ devm_spi_mem_dirmap_create(struct device *dev, struct spi_mem *mem, void devm_spi_mem_dirmap_destroy(struct device *dev, struct spi_mem_dirmap_desc *desc); +int spi_mem_poll_status(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 mask, u16 match, + unsigned long initial_delay_us, + unsigned long polling_delay_us, + u16 timeout); + int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv, struct module *owner);