From patchwork Wed Oct 9 14:01:12 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Th=C3=A9o_Lebrun?= X-Patchwork-Id: 13828491 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6D8D8CEDD9A for ; Wed, 9 Oct 2024 14:12:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=KN4a14PZ8SWOObiK/DnNIgNJ+gCkWYqBAi+54cWiank=; b=WY3d8nasDlHMgMsCpSZoTs4pPW r68pCEFIpbx54Fn9aewMoAiYxDj+tgrwbN8xEWxBsSnzSkzN7S8s3SvEfRG3tKLnHLyhtFBzWpdPE TllXB/jSo+XvMyH48O9pjNjK6hB/C0OfAsLcdF07Hg5HlmmCgO6aVVasZQQ5c7hFjnKyy131zCWDu 2zT+IohBGrD3rGBpxCf3H2eaQyCm/oKBNIVI3G+4HGZBI63tVxwPFkxkedSaCOmQmc9xx13woHVNB OoasoDWotI6dLwNFjMunLKLAlhnAKnbv7nmfA3fcJ3RoSxWYkMwHqsI/rnAf/UEe6PQbKccHwp23Q hxgIi3LA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1syXQY-00000009XsN-3X6O; Wed, 09 Oct 2024 14:12:34 +0000 Received: from relay8-d.mail.gandi.net ([2001:4b98:dc4:8::228]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1syXFb-00000009VKI-0els for linux-arm-kernel@lists.infradead.org; Wed, 09 Oct 2024 14:01:17 +0000 Received: by mail.gandi.net (Postfix) with ESMTPSA id 0E36B1BF20F; Wed, 9 Oct 2024 14:01:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1728482471; 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=KN4a14PZ8SWOObiK/DnNIgNJ+gCkWYqBAi+54cWiank=; b=V9WBB2Io+6zw/6SSxWaygTW2qxD+pr0kCkqPuKUogz+niFRH/WqurvOvsNdkgvY+v9WG++ 7quuOThLEQrCPzWM8Ot/8Psm8WFsex3ibZ0F+KTBbJqVY6NIW1zVhQ1GOEmiZkYdkyyKtX 0FGJwbqLQqLcXO7LFQdM1PKyQj8aBwhI7bs8FaW4wprwJlp9d4/OQvaVQnN0kRbNHWYMvk l1vxqOQxE4OBHnrNR1Sp8ON8mOLGnVWKtQO1zO0/iCnT9anaXAn+RmNRQ97nNr2LoE53os TnBMJ3AF0UVw3zmaJb08+DptPEPfKb+2nR0sh8WHXaG3h2oD1nzFtrzSjdnw6Q== From: =?utf-8?q?Th=C3=A9o_Lebrun?= Date: Wed, 09 Oct 2024 16:01:12 +0200 Subject: [PATCH v3 6/6] i2c: nomadik: support >=1MHz speed modes MIME-Version: 1.0 Message-Id: <20241009-mbly-i2c-v3-6-e7fd13bcf1c4@bootlin.com> References: <20241009-mbly-i2c-v3-0-e7fd13bcf1c4@bootlin.com> In-Reply-To: <20241009-mbly-i2c-v3-0-e7fd13bcf1c4@bootlin.com> To: Linus Walleij , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley Cc: linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Vladimir Kondratiev , =?utf-8?q?Gr=C3=A9?= =?utf-8?q?gory_Clement?= , Thomas Petazzoni , Tawfik Bayouk , =?utf-8?q?Th=C3=A9o_Lebrun?= X-Mailer: b4 0.14.2 X-GND-Sasl: theo.lebrun@bootlin.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241009_070116_426053_7603A3C7 X-CRM114-Status: GOOD ( 16.35 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org - BRCR value must go into the BRCR1 field when in high-speed mode. It goes into BRCR2 otherwise. - Remove fallback to standard mode if priv->sm > I2C_FREQ_MODE_FAST. - Set SM properly in probe; previously it only checked STANDARD versus FAST. Now we set STANDARD, FAST, FAST_PLUS or HIGH_SPEED. - Remove all comment sections saying we only support low-speeds. Reviewed-by: Linus Walleij Signed-off-by: Théo Lebrun --- drivers/i2c/busses/i2c-nomadik.c | 40 ++++++++++++++++------------------------ 1 file changed, 16 insertions(+), 24 deletions(-) diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c index 90e3390cd66de5b3aa47d94de7fb30e1d67ac70e..efb33802804fdde82fe6d38d4f89d0b898f1667e 100644 --- a/drivers/i2c/busses/i2c-nomadik.c +++ b/drivers/i2c/busses/i2c-nomadik.c @@ -397,7 +397,7 @@ static u32 load_i2c_mcr_reg(struct nmk_i2c_dev *priv, u16 flags) */ static void setup_i2c_controller(struct nmk_i2c_dev *priv) { - u32 brcr1, brcr2; + u32 brcr; u32 i2c_clk, div; u32 ns; u16 slsu; @@ -444,7 +444,7 @@ static void setup_i2c_controller(struct nmk_i2c_dev *priv) /* * The spec says, in case of std. mode the divider is * 2 whereas it is 3 for fast and fastplus mode of - * operation. TODO - high speed support. + * operation. */ div = (priv->clk_freq > I2C_MAX_STANDARD_MODE_FREQ) ? 3 : 2; @@ -452,34 +452,23 @@ static void setup_i2c_controller(struct nmk_i2c_dev *priv) * generate the mask for baud rate counters. The controller * has two baud rate counters. One is used for High speed * operation, and the other is for std, fast mode, fast mode - * plus operation. Currently we do not supprt high speed mode - * so set brcr1 to 0. + * plus operation. * * BRCR is a clock divider amount. Pick highest value that * leads to rate strictly below target. Eg when asking for * 400kHz you want a bus rate <=400kHz (and not >=400kHz). */ - brcr1 = FIELD_PREP(I2C_BRCR_BRCNT1, 0); - brcr2 = FIELD_PREP(I2C_BRCR_BRCNT2, DIV_ROUND_UP(i2c_clk, priv->clk_freq * div)); + brcr = DIV_ROUND_UP(i2c_clk, priv->clk_freq * div); + + if (priv->sm == I2C_FREQ_MODE_HIGH_SPEED) + brcr = FIELD_PREP(I2C_BRCR_BRCNT1, brcr); + else + brcr = FIELD_PREP(I2C_BRCR_BRCNT2, brcr); /* set the baud rate counter register */ - writel((brcr1 | brcr2), priv->virtbase + I2C_BRCR); + writel(brcr, priv->virtbase + I2C_BRCR); - /* - * set the speed mode. Currently we support - * only standard and fast mode of operation - * TODO - support for fast mode plus (up to 1Mb/s) - * and high speed (up to 3.4 Mb/s) - */ - if (priv->sm > I2C_FREQ_MODE_FAST) { - dev_err(&priv->adev->dev, - "do not support this mode defaulting to std. mode\n"); - brcr2 = FIELD_PREP(I2C_BRCR_BRCNT2, - i2c_clk / (I2C_MAX_STANDARD_MODE_FREQ * 2)); - writel((brcr1 | brcr2), priv->virtbase + I2C_BRCR); - writel(FIELD_PREP(I2C_CR_SM, I2C_FREQ_MODE_STANDARD), - priv->virtbase + I2C_CR); - } + /* set the speed mode */ writel(FIELD_PREP(I2C_CR_SM, priv->sm), priv->virtbase + I2C_CR); /* set the Tx and Rx FIFO threshold */ @@ -1020,11 +1009,14 @@ static void nmk_i2c_of_probe(struct device_node *np, if (of_property_read_u32(np, "clock-frequency", &priv->clk_freq)) priv->clk_freq = I2C_MAX_STANDARD_MODE_FREQ; - /* This driver only supports 'standard' and 'fast' modes of operation. */ if (priv->clk_freq <= I2C_MAX_STANDARD_MODE_FREQ) priv->sm = I2C_FREQ_MODE_STANDARD; - else + else if (priv->clk_freq <= I2C_MAX_FAST_MODE_FREQ) priv->sm = I2C_FREQ_MODE_FAST; + else if (priv->clk_freq <= I2C_MAX_FAST_MODE_PLUS_FREQ) + priv->sm = I2C_FREQ_MODE_FAST_PLUS; + else + priv->sm = I2C_FREQ_MODE_HIGH_SPEED; priv->tft = 1; /* Tx FIFO threshold */ priv->rft = 8; /* Rx FIFO threshold */