From patchwork Mon Nov 11 03:37:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuan Liu via B4 Relay X-Patchwork-Id: 13870204 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 087A73224; Mon, 11 Nov 2024 03:37:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731296230; cv=none; b=j41NGmdlPMRgR94xglabUKDE7UGHycrZzVtdGK3K64Xx7SIEo27lTtoR7chEsM8e9UCnngZjRBGV2h+fddv8kEzUAtd01j+AOugw2vAQjnduGia7+Xxfe//JvRHbghbwj4ln6EcLToi555vLTQS/v3QZm8JuTYVo8jbAB9b1TbM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731296230; c=relaxed/simple; bh=FLYPFnw2Yqnj3auU91LfHIFR9j23kCj3QGzsgZlM2TU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=NFDToJOjmd0WKxhI1yzQlhDL/NMgghoy00NRJURb8AfhbXqUGH89haysQlAfy+UxMNImagnesRefmiGNi+1HBTJc5v+aMz3mjqerxWmvxAe3JmOYxJA4et8XoiKiRFJRD7ViZFNNVf4OorXfOFePDL0bN6USdboJxOZW1/mnqo4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pgvqDa4p; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pgvqDa4p" Received: by smtp.kernel.org (Postfix) with ESMTPS id C9305C4CECF; Mon, 11 Nov 2024 03:37:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731296229; bh=FLYPFnw2Yqnj3auU91LfHIFR9j23kCj3QGzsgZlM2TU=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=pgvqDa4pX+626RzLwZsL24T9zfPieZu92smUBkx72aDNnWAfWqiJH7sjEBkfHQ14a jv9zS0gyJ/a6vC0CEjTH918NYMABEmiZ8PV5Gv6UxJrJD8weKKQHfyG4claUg/S4l/ G/N65cg0/2d8y0O++T8ieMKgiPV3VYb9Vwqek5Q6ioXYpk3mpXrgKMwISnQHyTC9Pr d7dz9Yr+6eOjtmN8tFVk+I3SWnH0HguJcVXZ/8prA+0uJxEFFRhaVyWN86mi6v3m8v SRB5JrktapbOgAGdWFjAygR5MPvPsCX1nRpHwnCKmnnzx0HwEylx6R8ldcI0ifUFKe /EwCR3aW8XsVw== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9B29D12D63; Mon, 11 Nov 2024 03:37:09 +0000 (UTC) From: Chuan Liu via B4 Relay Date: Mon, 11 Nov 2024 11:37:01 +0800 Subject: [PATCH v2 1/3] clk: Fix the CLK_IGNORE_UNUSED failure issue Precedence: bulk X-Mailing-List: linux-clk@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241111-fix_glitch_free-v2-1-0099fd9ad3e5@amlogic.com> References: <20241111-fix_glitch_free-v2-0-0099fd9ad3e5@amlogic.com> In-Reply-To: <20241111-fix_glitch_free-v2-0-0099fd9ad3e5@amlogic.com> To: Michael Turquette , Stephen Boyd , Neil Armstrong , Jerome Brunet , Kevin Hilman , Martin Blumenstingl Cc: linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Chuan Liu X-Mailer: b4 0.14.1 X-Developer-Signature: v=1; a=ed25519-sha256; t=1731296227; l=3533; i=chuan.liu@amlogic.com; s=20240902; h=from:subject:message-id; bh=9b1cy9TNBZPPfcNjZa5uI79KkJxq5esCtVNt/pf2DF4=; b=B3YI7KWQBzzPirhueg0Y4FP+swR7rBAu+MWHP4YpU+sGHKo/kUjKDGkCpEzczH87qc/QhIka2 B60vBX1oqjgDzindHyBmrnyp1s2NwPm++D2kOiKV4dLgTCeZYz/CqIX X-Developer-Key: i=chuan.liu@amlogic.com; a=ed25519; pk=fnKDB+81SoWGKW2GJNFkKy/ULvsDmJZRGBE7pR5Xcpo= X-Endpoint-Received: by B4 Relay for chuan.liu@amlogic.com/20240902 with auth_id=203 X-Original-From: Chuan Liu Reply-To: chuan.liu@amlogic.com From: Chuan Liu When the clk_disable_unused_subtree() function disables an unused clock, if CLK_OPS_PARENT_ENABLE is configured on the clock, clk_core_prepare_enable() and clk_core_disable_unprepare() are called directly, and these two functions do not determine CLK_IGNORE_UNUSED, This causes the clock to be disabled even if CLK_IGNORE_UNUSED is configured when clk_core_disable_unprepare() is called. Two new functions clk_disable_unprepare_unused() and clk_prepare_enable_unused() are added to resolve the preceding situation. The CLK_IGNORE_UNUSED judgment logic is added to these two functions. To prevent clock configuration CLK_IGNORE_UNUSED from possible failure. Fixes: a4b3518d146f ("clk: core: support clocks which requires parents enable (part 1)") Signed-off-by: Chuan Liu --- drivers/clk/clk.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 65 insertions(+), 2 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index d02451f951cf..6def76c30ce6 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -94,6 +94,7 @@ struct clk_core { struct hlist_node debug_node; #endif struct kref ref; + bool ignore_enabled; }; #define CREATE_TRACE_POINTS @@ -1479,6 +1480,68 @@ static void __init clk_unprepare_unused_subtree(struct clk_core *core) } } +static void __init clk_disable_unprepare_unused(struct clk_core *core) +{ + unsigned long flags; + + lockdep_assert_held(&prepare_lock); + + if (!core) + return; + + if ((core->enable_count == 0) && core->ops->disable && + !core->ignore_enabled) { + flags = clk_enable_lock(); + core->ops->disable(core->hw); + clk_enable_unlock(flags); + } + + if ((core->prepare_count == 0) && core->ops->unprepare && + !core->ignore_enabled) + core->ops->unprepare(core->hw); + + core->ignore_enabled = false; + + clk_disable_unprepare_unused(core->parent); +} + +static int __init clk_prepare_enable_unused(struct clk_core *core) +{ + int ret = 0; + unsigned long flags; + + lockdep_assert_held(&prepare_lock); + + if (!core) + return 0; + + ret = clk_prepare_enable_unused(core->parent); + if (ret) + return ret; + + if ((core->flags & CLK_IGNORE_UNUSED) && clk_core_is_enabled(core)) + core->ignore_enabled = true; + + if ((core->prepare_count == 0) && core->ops->prepare) { + ret = core->ops->prepare(core->hw); + if (ret) + goto disable_unprepare; + } + + if ((core->enable_count == 0) && core->ops->enable) { + flags = clk_enable_lock(); + ret = core->ops->enable(core->hw); + clk_enable_unlock(flags); + if (ret) + goto disable_unprepare; + } + + return 0; +disable_unprepare: + clk_disable_unprepare_unused(core->parent); + return ret; +} + static void __init clk_disable_unused_subtree(struct clk_core *core) { struct clk_core *child; @@ -1490,7 +1553,7 @@ static void __init clk_disable_unused_subtree(struct clk_core *core) clk_disable_unused_subtree(child); if (core->flags & CLK_OPS_PARENT_ENABLE) - clk_core_prepare_enable(core->parent); + clk_prepare_enable_unused(core->parent); flags = clk_enable_lock(); @@ -1517,7 +1580,7 @@ static void __init clk_disable_unused_subtree(struct clk_core *core) unlock_out: clk_enable_unlock(flags); if (core->flags & CLK_OPS_PARENT_ENABLE) - clk_core_disable_unprepare(core->parent); + clk_disable_unprepare_unused(core->parent); } static bool clk_ignore_unused __initdata;