From patchwork Wed Mar 27 08:43:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Louis Chauvet X-Patchwork-Id: 13605964 Received: from relay9-d.mail.gandi.net (relay9-d.mail.gandi.net [217.70.183.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27DAD36139; Wed, 27 Mar 2024 08:43:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.199 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711529030; cv=none; b=sfbyDh7SzJdI5eReq+qBUjdljw6hVl2Q70oJ2tzqmibE+JQYsBCThgiO3mTVntI29QQhOv0LbhvMvLNeWIeLHdpahIh+yTuudVN+EqeMhJsVgYVo5G8RrQwmbQ0xhx1G38WfeaMdMfk3YHQR+on89964YWKEEsJoK7wRok6Pvpo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711529030; c=relaxed/simple; bh=cbd6GULlhJHFj+W57GD2PRSA9IAx+XadTpMqn6sKLXU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=dFr6g8qk3USx7VFy6sMXW3NQIN6TFody6FEM+Q2EbpHsFJP4u5pxxoTnRa11SbUiBRVGEvtZYxuwjq2kDFacNwxLat893fSdIoAvt6C/EkzB4SwNRdEOVcThFzSCQKJgv8lpOhWPFFh3SjXN7pcHoJi7k3aONz19ACNn/ZruR0I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=gVC7Biy8; arc=none smtp.client-ip=217.70.183.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="gVC7Biy8" Received: by mail.gandi.net (Postfix) with ESMTPSA id 0F285FF80E; Wed, 27 Mar 2024 08:43:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1711529026; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ES9AYn9DDU2tdqD0EP064jr5Z2SbWzjTTb1Ww7Q0SZk=; b=gVC7Biy8Y13RV03xjjvfVigmmpyXTBmLYp7EGeQTclWgVI4zKSsBCGt+HYNpudpETKPtP0 tocr1x5ijZ0bBcj7o8lZJzUXzENZobQ9KYE6wbNLxa4K+NrCX6KbqfzS37ZJbMBQpHfSFH 5dpbnSW5fxv2pvQzwQVAm/L9I5s2dwJoLhr7YnX/izKKz48p4nC3iClA8DPc3OExfj5p+/ rb07KHdSG2lTlk1nriYAF/4V3RY09qkoVX31WwCmjNggk0+Tu4W0ISfZkFCCVJpGBAvhjg 3yWlcCl4yyBdtJHcshiKCAVSvo9SZD3L45OtBlUrx4Rk7k8fVguPeKHRn+gk5w== From: Louis Chauvet Date: Wed, 27 Mar 2024 09:43:38 +0100 Subject: [PATCH v3 3/3] spi: omap2-mcpsi: Enable MULTI-mode in more situations Precedence: bulk X-Mailing-List: linux-spi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240327-spi-omap2-mcspi-multi-mode-v3-3-c4ac329dd5a2@bootlin.com> References: <20240327-spi-omap2-mcspi-multi-mode-v3-0-c4ac329dd5a2@bootlin.com> In-Reply-To: <20240327-spi-omap2-mcspi-multi-mode-v3-0-c4ac329dd5a2@bootlin.com> To: Mark Brown Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, thomas.petazzoni@bootlin.com, Miquel Raynal , yen-mei.goh@keysight.com, koon-kee.lie@keysight.com, jeremie.dautheribes@bootlin.com, Louis Chauvet X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2389; i=louis.chauvet@bootlin.com; h=from:subject:message-id; bh=cbd6GULlhJHFj+W57GD2PRSA9IAx+XadTpMqn6sKLXU=; b=owEBbQKS/ZANAwAIASCtLsZbECziAcsmYgBmA9xAmZq8OlpvK656DoBX54JytpZ8m1w4dOlDkNzX jgKH6UeJAjMEAAEIAB0WIQRPj7g/vng8MQxQWQQgrS7GWxAs4gUCZgPcQAAKCRAgrS7GWxAs4pF1EA CkMw4PGPP4k3fo5bX3sCIYZlP3+TQ7DmgnF8RzvIyEugtDwbhe8tVz/xGRYduFgVQGShiJ5j92VvNW FTd9MMl/iG1DCQ0QIkktuB/ml3spIVcX0ChiTZcSkNdhrFXvVj4ldMtv4SXqItMnZP6fx0aFEXpVAp LyZpYwJYQoMSNKIL6emVbzCZUK+gY6f88q0g3Q76+pTu7LUAHjDsWdOFA89cctkhKnlZ0ycCxgHsCP vHQXe9yd/zb6k+vVDC+vypHL9/lugDF3marizLxtOkESbmgZv/Z14HVCXMKsDSX6N1ITaWx+sockff qfq++43/oOT2Gf6YL/VvA0VWHyYBHrySahcTrnK1ZC184RQ92wpc0Pws7OhnU0kQgU9+NgV3K1irdf oOQphnzj3xZATv/vm7ChWVj0oU3W86xc5Lv7SsSyoSvdUS3SQjERFlnwbyx6YivIDiCH/tQTVdn9z9 L3gUyb57zXckhZeVRr0NU9Qs2DgCKf7uDWdTYPj08sFr2JUszYSjAsXzYW1+W6PEdslQhs93nFfESA krqaJPo6LrAy8Q8LFP9iQcq2SRSL6oleJ4abxk5/kW1P2udRmms4Wm/WPEluY49ivt7x3UczLS3LSI 2QBOqlxo3B5i0rupnkegGX/eNZrqLkjuYiFZsa98UyZ1fnOipzjFPCXUjCyg== X-Developer-Key: i=louis.chauvet@bootlin.com; a=openpgp; fpr=8B7104AE9A272D6693F527F2EC1883F55E0B40A5 X-GND-Sasl: louis.chauvet@bootlin.com Enable multimode when a transfer of multiple small words can be transformed in a transfer with a single bigger word. This is allowed as long as the result on the cable is the same, so word_delay must be zero. Signed-off-by: Louis Chauvet --- I am not sure if this is the best place to put such "optimization". I think this improvment should be in the core, as it is not depending on the driver itself, but I think Mark suggested something like this so if that fits to what was expected, I am happy to share this small improvement. --- drivers/spi/spi-omap2-mcspi.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 002f29dbcea6..7e3083b83534 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -1277,11 +1277,24 @@ static int omap2_mcspi_prepare_message(struct spi_controller *ctlr, /* * Check if this transfer contains only one word; + * OR contains 1 to 4 words, with bits_per_word == 8 and no delay between each word + * OR contains 1 to 2 words, with bits_per_word == 16 and no delay between each word + * + * If one of the two last case is true, this also change the bits_per_word of this + * transfer to make it a bit faster. + * It's not an issue to change the bits_per_word here even if the multi-mode is not + * applicable for this message, the signal on the wire will be the same. */ if (bits_per_word < 8 && tr->len == 1) { /* multi-mode is applicable, only one word (1..7 bits) */ + } else if (tr->word_delay.value == 0 && bits_per_word == 8 && tr->len <= 4) { + /* multi-mode is applicable, only one "bigger" word (8,16,24,32 bits) */ + tr->bits_per_word = tr->len * bits_per_word; + } else if (tr->word_delay.value == 0 && bits_per_word == 16 && tr->len <= 2) { + /* multi-mode is applicable, only one "bigger" word (16,32 bits) */ + tr->bits_per_word = tr->len * bits_per_word / 2; } else if (bits_per_word >= 8 && tr->len == bits_per_word / 8) { - /* multi-mode is applicable, only one word (8..32 bits) */ + /* multi-mode is applicable, only one word (9..15,17..32 bits) */ } else { /* multi-mode is not applicable: more than one word in the transfer */ mcspi->use_multi_mode = false;