From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.gentoo.org (woodpecker.gentoo.org [140.211.166.183]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D25D32E3384; Sat, 22 Mar 2025 16:19:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=140.211.166.183 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742660393; cv=none; b=S+VEMVWMZ04n7mO0/f46XQhQOBNBNg86ozULkGp08T3V4d6jEpY4I+Fs36KtE7ytpeI1q1h7tzWyDcvlJrilJ3FhQ+7N6+4jPLU9/sDWpJXKlmhMQ1vKgI3hEpE9A9z6YE8NU0gvOhaL7Zv2KbnBHJKrwjLTSC1ittfmV1sxn90= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742660393; c=relaxed/simple; bh=naMh97xMyS6pY/6Ggyyl8UpM+OuNhOND4r5QMhewit0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=p6WgPIUUvdX4l/RkGalR2jYU7KJ1jAWaJ1Tm8FQsGTtWi23n9/iis6p/N0u6uxgssZF5V+WB0bcrr0KODJ1Vs1ve1isP5Ltm+uqLyJI4/lq7rD1/tesnqoklVhiz4LZjjakv3EoUhXUnjNuTAmFa6LKTEknnv19/WMKQ3h9c4TQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gentoo.org; spf=pass smtp.mailfrom=gentoo.org; arc=none smtp.client-ip=140.211.166.183 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gentoo.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gentoo.org Received: from localhost (unknown [116.232.48.233]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dlan) by smtp.gentoo.org (Postfix) with ESMTPSA id BA60834307B; Sat, 22 Mar 2025 16:19:49 +0000 (UTC) Date: Sat, 22 Mar 2025 16:19:45 +0000 From: Yixun Lan To: Alex Elder Cc: p.zabel@pengutronix.de, mturquette@baylibre.com, sboyd@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, heylenay@4d2.org, guodong@riscstar.com, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, spacemit@lists.linux.dev, devicetree@vger.kernel.org, linux-clk@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RESEND 3/7] clk: spacemit: add reset controller support Message-ID: <20250322161945-GYC11633@gentoo> References: <20250321151831.623575-1-elder@riscstar.com> <20250321151831.623575-4-elder@riscstar.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250321151831.623575-4-elder@riscstar.com> Hi Alex: On 10:18 Fri 21 Mar , Alex Elder wrote: > Define ccu_reset_data as a structure that contains the constant > register offset and bitmasks used to assert and deassert a reset > control on a SpacemiT K1 CCU. Define ccu_reset_controller_data as > a structure that contains the address of an array of those structures > and a count of the number of elements in the array. > > Add a pointer to a ccu_reset_controller_data structure to the > k1_ccu_data structure. Reset support is optional for SpacemiT CCUs; > the new pointer field will be null for CCUs without any resets. > > Finally, define a new ccu_reset_controller structure, which (for > a CCU with resets) contains a pointer to the constant reset data, > the regmap to be used for the controller, and an embedded a reset > controller structure. > > Each reset control is asserted or deasserted by updating bits in > a register. The bits used are defined by an assert mask and a > deassert mask. In some cases, one (non-zero) mask asserts reset > and a different (non-zero) mask deasserts it. Otherwise one mask > is nonzero, and the other is zero. Either way, the bits in > both masks are cleared, then either the assert mask or the deassert > mask is set in a register to affect the state of a reset control. > > Signed-off-by: Alex Elder > --- > drivers/clk/spacemit/ccu-k1.c | 93 +++++++++++++++++++++++++++++++++++ > 1 file changed, 93 insertions(+) > > diff --git a/drivers/clk/spacemit/ccu-k1.c b/drivers/clk/spacemit/ccu-k1.c > index f7367271396a0..6d879411c6c05 100644 > --- a/drivers/clk/spacemit/ccu-k1.c > +++ b/drivers/clk/spacemit/ccu-k1.c > @@ -10,6 +10,7 @@ > #include > #include > #include > +#include > > #include "ccu_common.h" > #include "ccu_pll.h" > @@ -134,8 +135,26 @@ struct spacemit_ccu_clk { > struct clk_hw *hw; > }; > > +struct ccu_reset_data { > + u32 offset; > + u32 assert_mask; > + u32 deassert_mask; > +}; > + > +struct ccu_reset_controller_data { > + u32 count; > + const struct ccu_reset_data *data; /* array */ > +}; > + > struct k1_ccu_data { > struct spacemit_ccu_clk *clk; /* array with sentinel */ > + const struct ccu_reset_controller_data *rst_data; > +}; > + > +struct ccu_reset_controller { > + struct regmap *regmap; > + const struct ccu_reset_controller_data *data; > + struct reset_controller_dev rcdev; > }; > > /* APBS clocks start */ > @@ -1630,6 +1649,48 @@ static const struct k1_ccu_data k1_ccu_apmu_data = { > .clk = k1_ccu_apmu_clks, > }; > > +static struct ccu_reset_controller * > +rcdev_to_controller(struct reset_controller_dev *rcdev) I'd suggest to avoid the line break to make it slightly more readable, intuitive as the 80 column limit isn't hard rule there are maybe more place similar to this, I won't add more comments https://github.com/torvalds/linux/commit/bdc48fa11e46f867ea4d75fa59ee87a7f48be144 > +{ > + return container_of(rcdev, struct ccu_reset_controller, rcdev); > +} since this function is only used once, open-code it? but I'd fine with either way if you prefer to keep it > + > +static int > +k1_rst_update(struct reset_controller_dev *rcdev, unsigned long id, bool assert) s/k1_rst_update/k1_reset_update/g this is a taste change, but I found more people follow this when grep driver/reset > +{ > + struct ccu_reset_controller *controller = rcdev_to_controller(rcdev); > + struct regmap *regmap = controller->regmap; > + const struct ccu_reset_data *data; > + u32 val; > + int ret; > + > + data = &controller->data->data[id]; > + > + ret = regmap_read(regmap, data->offset, &val); > + if (ret) > + return ret; > + > + val &= ~(data->assert_mask | data->deassert_mask); > + val |= assert ? data->assert_mask : data->deassert_mask; > + > + return regmap_write(regmap, data->offset, val); > +} > + > +static int k1_rst_assert(struct reset_controller_dev *rcdev, unsigned long id) same reason, rst -> reset, more below > +{ > + return k1_rst_update(rcdev, id, true); > +} > + > +static int k1_rst_deassert(struct reset_controller_dev *rcdev, unsigned long id) > +{ > + return k1_rst_update(rcdev, id, false); > +} > + > +static const struct reset_control_ops k1_reset_control_ops = { > + .assert = k1_rst_assert, > + .deassert = k1_rst_deassert, > +}; > + > static int k1_ccu_register(struct device *dev, struct regmap *regmap, > struct regmap *lock_regmap, > struct spacemit_ccu_clk *clks) > @@ -1675,6 +1736,33 @@ static int k1_ccu_register(struct device *dev, struct regmap *regmap, > return ret; > } > > +static int > +k1_reset_controller_register(struct device *dev, struct regmap *regmap, > + const struct ccu_reset_controller_data *data) > +{ > + struct ccu_reset_controller *controller; > + struct reset_controller_dev *rcdev; > + > + /* Resets are optional */ > + if (!data) > + return 0; > + > + controller = devm_kzalloc(dev, sizeof(*controller), GFP_KERNEL); > + if (!controller) > + return -ENOMEM; > + > + controller->regmap = regmap; > + controller->data = data; > + > + rcdev = &controller->rcdev; .. > + rcdev->owner = THIS_MODULE; move to last? > + rcdev->nr_resets = data->count; > + rcdev->ops = &k1_reset_control_ops; > + rcdev->of_node = dev->of_node; > + > + return devm_reset_controller_register(dev, rcdev); > +} > + > static int k1_ccu_probe(struct platform_device *pdev) > { > struct regmap *base_regmap, *lock_regmap = NULL; > @@ -1710,6 +1798,11 @@ static int k1_ccu_probe(struct platform_device *pdev) > if (ret) > return dev_err_probe(dev, ret, "failed to register clocks\n"); > > + ret = k1_reset_controller_register(dev, base_regmap, data->rst_data); .. > + if (ret) > + return dev_err_probe(dev, ret, > + "failed to register reset controller\n"); same 100 column reason > + > return 0; > } > > -- > 2.43.0 > -- Yixun Lan (dlan) Gentoo Linux Developer GPG Key ID AABEFD55