From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (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 E43A21A731; Fri, 23 Feb 2024 09:32:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708680779; cv=none; b=fuwxbviTqkX1LRWh7N4uf2dk56dSicgXS4gFR5M0aw4cCv9e/cXUmq5DM/eljcRgf6U2xEGyx7zpLA3LTUTKlrMJ6GzXTNkMq7c3GUFp0+0KNGZj4D4xrSjKRo8CObAkwglVh2CZC6eFHgFbQCUvrzwJeBnRrD2cd4jbRJ3JV80= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708680779; c=relaxed/simple; bh=e4RXBe7SdrRLGGStxY/kvqt/kAPWHBSBirHEGGNnVHY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=rYwY9dipaFyv1OgyVklSj+uHjdvMdScWkejES8R29gd6+z/QykzG4vy4CWRFUeztGh6ekGhiq2hcMwgHdE98LEE2MRvk658EEGIlxu0FGa+I4xYV5b/csZ+7HGSyaT+Q6QXc9PBzo+d1tp/uzufXb2QcagiaPYChC9peIwRmo3c= 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=e5FkuvEU; arc=none smtp.client-ip=217.70.183.200 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="e5FkuvEU" Received: by mail.gandi.net (Postfix) with ESMTPSA id 5792D20013; Fri, 23 Feb 2024 09:32:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1708680768; 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=x2oRLe0RRlPq8BsMAid2UDLfRRqpSJFqF07a/MXQocI=; b=e5FkuvEU2Mtn0cO+/Pa1PC8U8ugIYJVnlW4u1isMnfRprKNsfXGnJv0iLEelAWSBkPl1tH 6B0/VxrzJaFqOYsWkxXb+itolf3E4GBHd8De+VJHYTFVe7W5lz+ZjJYyWd7shkQSQxO1H5 v9GX8t6lPIvjgjoeWbNr5tU8SyXmZDP1EBO828Ks0U7oBxUacIDgoljkHKg+AcjzPdBwaQ sD3IFPuSOI2/T1JIuIonLCdH6b4SFvzaYrLoZco63ffJwl88Pv9WdZ9PKAl5D7RgHt0y4q Eqv9VIy+ZOIeMMEIfmLHehO9FidUyC+yM6dw6lPs1MQvNPS5KlAXIcM6Qv3KaA== From: Louis Chauvet Date: Fri, 23 Feb 2024 10:32:13 +0100 Subject: [PATCH v2 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 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20240223-spi-omap2-mcspi-multi-mode-v2-3-afe94476b9c3@bootlin.com> References: <20240223-spi-omap2-mcspi-multi-mode-v2-0-afe94476b9c3@bootlin.com> In-Reply-To: <20240223-spi-omap2-mcspi-multi-mode-v2-0-afe94476b9c3@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=2499; i=louis.chauvet@bootlin.com; h=from:subject:message-id; bh=e4RXBe7SdrRLGGStxY/kvqt/kAPWHBSBirHEGGNnVHY=; b=owEBbQKS/ZANAwAIASCtLsZbECziAcsmYgBl2GY3HapgT8vFrAzfkho/rXRT8omzMteYRE6HA4M9 wXk7xeeJAjMEAAEIAB0WIQRPj7g/vng8MQxQWQQgrS7GWxAs4gUCZdhmNwAKCRAgrS7GWxAs4mxzD/ 0debrX/LIA5gA7Z8tqa7TLIMcoQ0g8WrhuUEvSDtPE+T97+U0bdmBZoTTWtDv517MiqFcjO8JUjKJo 7rVm1WjO4FKfAZX3MV0vXWPsPqQsmSTsCNEofs1AYGhJV67el0jM+NCfWnZcRX3sxEhGbvgmGUVmx0 3CitqWMhGGCVsz8H3UncBec47ut7lHvmNpQ1oY41KyLbwmizqCoIwxJYMimwa6rTRAgu4+CWIkwdt1 ZytzZMlcxrz8p4pb62qv3ei7KE/o7pU3RMNTe39LoAiReSyjhSXlMgDgFXVWhlgZUYgxLdTxKa70Lw Av41sUyxGTFN/HMMFoQFdQ04/5L5WmohvgwjC00VLPaMa+itxmxlOYOcxRWqu+/09NimNImd3GhRf4 hso9WljUe9vPBxl6qhfax3iZ4lZH1KcP9jgmHPpzD05cohjIGXBn8gks6WJuS8MP7UtJFJFtQPCk+v PQbTqcz6135eTKjdL1XyoApJzYHYuUoqNEr0QV1G/kzleFVBH+y+PZeC0YETr3J6o9hFeGX1rObvvP 52fGXdSmGd7fWwi4QnR1faq2TnnBtxLtw015zUhcWJbiNSRLNyTwICzzzxTkx6aUgeEu2OzJtLVq2d +GqOShz/Yve+48NUEGNi010THIKw3+e/j84uC8+8YeK9PXJc1IJnEdFpP+Rg== 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 | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 36075c4416d5..f64cc8cc7587 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -1397,14 +1397,26 @@ static int omap2_mcspi_prepare_message(struct spi_controller *ctlr, else bits_per_word = tr->bits_per_word; - /* Only a single channel can have the FORCE bit enabled /* * 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; -- 2.43.0