From patchwork Sat May 21 00:53:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Baryshkov X-Patchwork-Id: 12857641 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 81AFFC433F5 for ; Sat, 21 May 2022 00:53:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232972AbiEUAx6 (ORCPT ); Fri, 20 May 2022 20:53:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40680 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237569AbiEUAx5 (ORCPT ); Fri, 20 May 2022 20:53:57 -0400 Received: from mail-lf1-x12e.google.com (mail-lf1-x12e.google.com [IPv6:2a00:1450:4864:20::12e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20E451AD5B0 for ; Fri, 20 May 2022 17:53:56 -0700 (PDT) Received: by mail-lf1-x12e.google.com with SMTP id bu29so17024713lfb.0 for ; Fri, 20 May 2022 17:53:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=T+YiK8dxsrGm0m2VhiIGzrrysQ7BgDNB7nIlgNquoww=; b=sSIXdE9p5G79cWnri1fdGlFgZb76DuCz93192G8Ry0Ksrk4jLE8H5YZ3qzVust7aMO nYDIoRWJKjVQP0xXSMnnLi6SkNRw9yfOGMo0jUfH67MImHJflnyuc8rpt8mtMKIuFyPH X6EPY7eCfJunW57xE1IVqa3xunNJBh/AtBnAXR8fucVqoOB41Crqj1m9RGVL0BG2aLiL 95mzaogqx5/ZQHGb4MlwNMp++vPW5q6BohkucswofxW1yXhF4NOdJsSnynLpWmIW5ysZ RQlFJOH5TUETMpqLmuN2EtivwkgFnf2p0d9RRCqNOPjSn50DXfdEkXkVO0fgIzWoMCd+ qj5Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=T+YiK8dxsrGm0m2VhiIGzrrysQ7BgDNB7nIlgNquoww=; b=V5/+YrubDuN6t5/uOJrP5Xfw7eXyjrLpA1cPetl1qeCZJOI3UxkCa2Jq00nqYBTdSE BtLpoOFAlnUaEe96TpMi7o1vGnKhYJYsV1JZAipQMC/5c0fSXIs7vxgEGQ/F1p4TQGub Rfz4qIW3HkT80qI+RNP0XXSvOHmt9hBV9kOnGgmuaLy4Wo3YqKtTYLTqNJetRUJIeKtk zDSm+BWRUeG6aUEWan61TxmaME64ZGo1/K6b4cEfiG/tM8444hA0AI1VvCTvC9JcxgKt vcFt+dKliboXcaYtEUQu/VM31lIg7c4cs9EpqXMKOEfiyVtIldxXBCljXlMU+2XFUjg6 A2gw== X-Gm-Message-State: AOAM532r/nG5VvSlfIbECIqb44Jxn4ODXGLNrGyCmIvNFuRisnI4GMic yRB7JRGntI11gR+tQHah9dzczw== X-Google-Smtp-Source: ABdhPJxEqoUT09DUnay3AI+EsKfFnUjXPSHSi6TWr+Zj+GeIKtsXACbcpOQGvEZy4t1WkoXRr4iFGw== X-Received: by 2002:a05:6512:3b93:b0:474:188b:1c99 with SMTP id g19-20020a0565123b9300b00474188b1c99mr8708430lfv.549.1653094434408; Fri, 20 May 2022 17:53:54 -0700 (PDT) Received: from eriador.lan ([2001:470:dd84:abc0::8a5]) by smtp.gmail.com with ESMTPSA id u14-20020a056512094e00b0047255d21187sm844559lft.182.2022.05.20.17.53.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 May 2022 17:53:53 -0700 (PDT) From: Dmitry Baryshkov To: Andy Gross , Bjorn Andersson , Stephen Boyd , Michael Turquette , Taniya Das , Lorenzo Pieralisi , =?utf-8?q?Krzysztof_Wilczy?= =?utf-8?q?=C5=84ski?= , Bjorn Helgaas Cc: Johan Hovold , linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org, linux-pci@vger.kernel.org Subject: [PATCH v7 4/8] clk: qcom: regmap: add PHY clock source implementation Date: Sat, 21 May 2022 03:53:39 +0300 Message-Id: <20220521005343.1429642-5-dmitry.baryshkov@linaro.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220521005343.1429642-1-dmitry.baryshkov@linaro.org> References: <20220521005343.1429642-1-dmitry.baryshkov@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On recent Qualcomm platforms the QMP PIPE clocks feed into a set of muxes which must be parked to the "safe" source (bi_tcxo) when corresponding GDSC is turned off and on again. Currently this is handcoded in the PCIe driver by reparenting the gcc_pipe_N_clk_src clock. However the same code sequence should be applied in the pcie-qcom endpoint, USB3 and UFS drivers. Rather than copying this sequence over and over again, follow the example of clk_rcg2_shared_ops and implement this parking in the enable() and disable() clock operations. Supplement the regmap-mux with the new clk_regmap_phy_mux type, which implements such multiplexers as a simple gate clocks. This is possible since each of these multiplexers has just two clock sources: one coming from the PHY and a reference (XO) one. If the clock is running off the from-PHY source, report it as enabled. Report it as disabled otherwise (if it uses reference source). This way the PHY will disable the pipe clock before turning off the GDSC, which in turn would lead to disabling corresponding pipe_clk_src (and thus it being parked to a safe, reference clock source). And vice versa, after enabling the GDSC the PHY will enable the pipe clock, which would cause pipe_clk_src to be switched from a safe source to the working one. Signed-off-by: Dmitry Baryshkov --- drivers/clk/qcom/Makefile | 1 + drivers/clk/qcom/clk-regmap-phy-mux.c | 62 +++++++++++++++++++++++++++ drivers/clk/qcom/clk-regmap-phy-mux.h | 33 ++++++++++++++ 3 files changed, 96 insertions(+) create mode 100644 drivers/clk/qcom/clk-regmap-phy-mux.c create mode 100644 drivers/clk/qcom/clk-regmap-phy-mux.h diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile index 36789f5233ef..08594230c1c1 100644 --- a/drivers/clk/qcom/Makefile +++ b/drivers/clk/qcom/Makefile @@ -11,6 +11,7 @@ clk-qcom-y += clk-branch.o clk-qcom-y += clk-regmap-divider.o clk-qcom-y += clk-regmap-mux.o clk-qcom-y += clk-regmap-mux-div.o +clk-qcom-y += clk-regmap-phy-mux.o clk-qcom-$(CONFIG_KRAIT_CLOCKS) += clk-krait.o clk-qcom-y += clk-hfpll.o clk-qcom-y += reset.o diff --git a/drivers/clk/qcom/clk-regmap-phy-mux.c b/drivers/clk/qcom/clk-regmap-phy-mux.c new file mode 100644 index 000000000000..a1adc075b471 --- /dev/null +++ b/drivers/clk/qcom/clk-regmap-phy-mux.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2022, Linaro Ltd. + */ + +#include +#include +#include +#include + +#include "clk-regmap.h" +#include "clk-regmap-phy-mux.h" + +#define PHY_MUX_MASK GENMASK(1, 0) +#define PHY_MUX_PHY_SRC 0 +#define PHY_MUX_REF_SRC 2 + +static inline struct clk_regmap_phy_mux *to_clk_regmap_phy_mux(struct clk_regmap *clkr) +{ + return container_of(clkr, struct clk_regmap_phy_mux, clkr); +} + +static int phy_mux_is_enabled(struct clk_hw *hw) +{ + struct clk_regmap *clkr = to_clk_regmap(hw); + struct clk_regmap_phy_mux *phy_mux = to_clk_regmap_phy_mux(clkr); + unsigned int val; + + regmap_read(clkr->regmap, phy_mux->reg, &val); + val = FIELD_GET(PHY_MUX_MASK, val); + + WARN_ON(val != PHY_MUX_PHY_SRC && val != PHY_MUX_REF_SRC); + + return val == PHY_MUX_PHY_SRC; +} + +static int phy_mux_enable(struct clk_hw *hw) +{ + struct clk_regmap *clkr = to_clk_regmap(hw); + struct clk_regmap_phy_mux *phy_mux = to_clk_regmap_phy_mux(clkr); + + return regmap_update_bits(clkr->regmap, phy_mux->reg, + PHY_MUX_MASK, + FIELD_PREP(PHY_MUX_MASK, PHY_MUX_PHY_SRC)); +} + +static void phy_mux_disable(struct clk_hw *hw) +{ + struct clk_regmap *clkr = to_clk_regmap(hw); + struct clk_regmap_phy_mux *phy_mux = to_clk_regmap_phy_mux(clkr); + + regmap_update_bits(clkr->regmap, phy_mux->reg, + PHY_MUX_MASK, + FIELD_PREP(PHY_MUX_MASK, PHY_MUX_REF_SRC)); +} + +const struct clk_ops clk_regmap_phy_mux_ops = { + .enable = phy_mux_enable, + .disable = phy_mux_disable, + .is_enabled = phy_mux_is_enabled, +}; +EXPORT_SYMBOL_GPL(clk_regmap_phy_mux_ops); diff --git a/drivers/clk/qcom/clk-regmap-phy-mux.h b/drivers/clk/qcom/clk-regmap-phy-mux.h new file mode 100644 index 000000000000..614dd384695c --- /dev/null +++ b/drivers/clk/qcom/clk-regmap-phy-mux.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2022, Linaro Ltd. + */ + +#ifndef __QCOM_CLK_REGMAP_PHY_MUX_H__ +#define __QCOM_CLK_REGMAP_PHY_MUX_H__ + +#include "clk-regmap.h" + +/* + * A clock implementation for PHY pipe and symbols clock muxes. + * + * If the clock is running off the from-PHY source, report it as enabled. + * Report it as disabled otherwise (if it uses reference source). + * + * This way the PHY will disable the pipe clock before turning off the GDSC, + * which in turn would lead to disabling corresponding pipe_clk_src (and thus + * it being parked to a safe, reference clock source). And vice versa, after + * enabling the GDSC the PHY will enable the pipe clock, which would cause + * pipe_clk_src to be switched from a safe source to the working one. + * + * For some platforms this should be used for the UFS symbol_clk_src clocks + * too. + */ +struct clk_regmap_phy_mux { + u32 reg; + struct clk_regmap clkr; +}; + +extern const struct clk_ops clk_regmap_phy_mux_ops; + +#endif