From mboxrd@z Thu Jan 1 00:00:00 1970 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 326F7E8FDB1 for ; Mon, 29 Dec 2025 04:32:28 +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:Content-Transfer-Encoding: MIME-Version:Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=7qsA59Z6VFaS78baJa7kQDv/8RvoseWsssX5vdMZZ1o=; b=02JkCj8elsoQN3QHePDghFqw5A CXTZN1bIfNdrmxrKGCVfvx6/YEFfjO1onvyWAB0SeHlS2Fb1F1YtdnFrYq6U4cxailwu3efijLJl/ dtOc6kx7ePhiSsvJzAe8bMO9MP3A2Re0Y5Xmu9XGHuGxKngbZcZi67typdEHPTwJkcMxZJeU+TT6X 7+u+fVm84E487RatKjzzOCMKwiYpy7AyL065QfgFOxjGO0pfZwxeToNDoeQTtTDJt8MXgXJEX3geL ax8xIh8RpDH4XcGyRlCLSlD48UV92Wu2tbyaRw05Y6yMwWmE2MppIp6I2ezQGX3KNNCPDjCgh5awZ yOER17aw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1va4vf-00000003JtL-2JEA; Mon, 29 Dec 2025 04:32:23 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1va4vd-00000003Jsx-3P06 for linux-mediatek@lists.infradead.org; Mon, 29 Dec 2025 04:32:22 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 2B6C240DC5; Mon, 29 Dec 2025 04:32:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4716C4CEF7; Mon, 29 Dec 2025 04:32:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1766982739; bh=kLJp2zW30SyEirLd2hJk5YmCXnYsCmPJ8ttStB77kFw=; h=From:To:Cc:Subject:Date:From; b=R17pDxF2cYQGJjr0Lui2Oskacm9bRRnadyTcMahexEeGvO8Ps+pERAKLWB9+MvSyj Gb+GMAyo0U+bGza6YOMQXCf4uBGdozhNV3kLFPUE8wrQyoLOYtH5DLxRX2y3fZpGNY sVhMUjr4bQ2eNLUhhYBJBPTuUbmhMOpeHcH2IZPSW7ZII/aftWtl55uCpX29x7G30P T92ByQqgJVMEVaEQJqVaaNlRhE6ny2NEr9DG7E5sVdbeUizVVe4iDhet4VE7ttrQiT d+kIEmC/ZCfmSBHoPuvd0OdF2GvRtAyJphGQN2s2Kd72iJvVWzKNEUVOL7O658a3Bt ABlYzJ3S4+5Wg== From: Tzung-Bi Shih To: Bjorn Andersson , Mathieu Poirier Cc: Matthias Brugger , AngeloGioacchino Del Regno , linux-remoteproc@vger.kernel.org, linux-mediatek@lists.infradead.org, tzungbi@kernel.org Subject: [PATCH] remoteproc: mediatek: Break lock dependency to `prepare_lock` Date: Mon, 29 Dec 2025 04:31:46 +0000 Message-ID: <20251229043146.4102967-1-tzungbi@kernel.org> X-Mailer: git-send-email 2.52.0.351.gbe84eed79e-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251228_203221_891046_1A378D9E X-CRM114-Status: GOOD ( 12.28 ) X-BeenThere: linux-mediatek@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-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org `scp_ipi_send` acquires `prepare_lock` via `clk_prepare_enable` while the caller often holds `ec_dev->lock` (e.g., `cros_ec_cmd_xfer`). The reverse dependency exists where `clk_prepare` can trigger operations that eventually take `ec_dev->lock` (e.g., via sysfs/regulator/genpd). Move clock prepare / unprepare operations to remoteproc prepare() / unprepare() callbacks to break the lock dependency from `ec_dev->lock` to `prepare_lock`. This breaks the dependency chain in the lockdep report: > WARNING: possible circular locking dependency detected > ... > the existing dependency chain (in reverse order) is: > ... > -> #0 (prepare_lock){+.+.}-{3:3}: > __lock_acquire > lock_acquire > __mutex_lock_common > mutex_lock_nested > clk_prepare > scp_ipi_send [mtk_scp_ipi] > scp_send_ipi [mtk_scp] > mtk_rpmsg_send [mtk_rpmsg] > rpmsg_send [rpmsg_core] > cros_ec_pkt_xfer_rpmsg [cros_ec_rpmsg] Signed-off-by: Tzung-Bi Shih --- drivers/remoteproc/mtk_scp.c | 39 +++++++++++++++++++++++--------- drivers/remoteproc/mtk_scp_ipi.c | 4 ++-- 2 files changed, 30 insertions(+), 13 deletions(-) diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c index db8fd045468d..98d00bd5200c 100644 --- a/drivers/remoteproc/mtk_scp.c +++ b/drivers/remoteproc/mtk_scp.c @@ -283,7 +283,7 @@ static irqreturn_t scp_irq_handler(int irq, void *priv) struct mtk_scp *scp = priv; int ret; - ret = clk_prepare_enable(scp->clk); + ret = clk_enable(scp->clk); if (ret) { dev_err(scp->dev, "failed to enable clocks\n"); return IRQ_NONE; @@ -291,7 +291,7 @@ static irqreturn_t scp_irq_handler(int irq, void *priv) scp->data->scp_irq_handler(scp); - clk_disable_unprepare(scp->clk); + clk_disable(scp->clk); return IRQ_HANDLED; } @@ -665,7 +665,7 @@ static int scp_load(struct rproc *rproc, const struct firmware *fw) struct device *dev = scp->dev; int ret; - ret = clk_prepare_enable(scp->clk); + ret = clk_enable(scp->clk); if (ret) { dev_err(dev, "failed to enable clocks\n"); return ret; @@ -680,7 +680,7 @@ static int scp_load(struct rproc *rproc, const struct firmware *fw) ret = scp_elf_load_segments(rproc, fw); leave: - clk_disable_unprepare(scp->clk); + clk_disable(scp->clk); return ret; } @@ -691,14 +691,14 @@ static int scp_parse_fw(struct rproc *rproc, const struct firmware *fw) struct device *dev = scp->dev; int ret; - ret = clk_prepare_enable(scp->clk); + ret = clk_enable(scp->clk); if (ret) { dev_err(dev, "failed to enable clocks\n"); return ret; } ret = scp_ipi_init(scp, fw); - clk_disable_unprepare(scp->clk); + clk_disable(scp->clk); return ret; } @@ -709,7 +709,7 @@ static int scp_start(struct rproc *rproc) struct scp_run *run = &scp->run; int ret; - ret = clk_prepare_enable(scp->clk); + ret = clk_enable(scp->clk); if (ret) { dev_err(dev, "failed to enable clocks\n"); return ret; @@ -734,14 +734,14 @@ static int scp_start(struct rproc *rproc) goto stop; } - clk_disable_unprepare(scp->clk); + clk_disable(scp->clk); dev_info(dev, "SCP is ready. FW version %s\n", run->fw_ver); return 0; stop: scp->data->scp_reset_assert(scp); - clk_disable_unprepare(scp->clk); + clk_disable(scp->clk); return ret; } @@ -909,7 +909,7 @@ static int scp_stop(struct rproc *rproc) struct mtk_scp *scp = rproc->priv; int ret; - ret = clk_prepare_enable(scp->clk); + ret = clk_enable(scp->clk); if (ret) { dev_err(scp->dev, "failed to enable clocks\n"); return ret; @@ -917,12 +917,29 @@ static int scp_stop(struct rproc *rproc) scp->data->scp_reset_assert(scp); scp->data->scp_stop(scp); - clk_disable_unprepare(scp->clk); + clk_disable(scp->clk); return 0; } +static int scp_prepare(struct rproc *rproc) +{ + struct mtk_scp *scp = rproc->priv; + + return clk_prepare(scp->clk); +} + +static int scp_unprepare(struct rproc *rproc) +{ + struct mtk_scp *scp = rproc->priv; + + clk_unprepare(scp->clk); + return 0; +} + static const struct rproc_ops scp_ops = { + .prepare = scp_prepare, + .unprepare = scp_unprepare, .start = scp_start, .stop = scp_stop, .load = scp_load, diff --git a/drivers/remoteproc/mtk_scp_ipi.c b/drivers/remoteproc/mtk_scp_ipi.c index c068227e251e..7a37e273b3af 100644 --- a/drivers/remoteproc/mtk_scp_ipi.c +++ b/drivers/remoteproc/mtk_scp_ipi.c @@ -171,7 +171,7 @@ int scp_ipi_send(struct mtk_scp *scp, u32 id, void *buf, unsigned int len, WARN_ON(len > scp_sizes->ipi_share_buffer_size) || WARN_ON(!buf)) return -EINVAL; - ret = clk_prepare_enable(scp->clk); + ret = clk_enable(scp->clk); if (ret) { dev_err(scp->dev, "failed to enable clock\n"); return ret; @@ -211,7 +211,7 @@ int scp_ipi_send(struct mtk_scp *scp, u32 id, void *buf, unsigned int len, unlock_mutex: mutex_unlock(&scp->send_lock); - clk_disable_unprepare(scp->clk); + clk_disable(scp->clk); return ret; } -- 2.52.0.351.gbe84eed79e-goog