From patchwork Thu Sep 15 07:24:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: AngeloGioacchino Del Regno X-Patchwork-Id: 12976963 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 AC6DCECAAD3 for ; Thu, 15 Sep 2022 07:30:16 +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:References:In-Reply-To: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:List-Owner; bh=ryfq+TI5BWyYPq2BGCAPBLd5iScWrzhnlKzvqFq8vC4=; b=QKxX3fs7BUaBZDp6FTYrQx4WFI j2A4S1j50JH8Vd4orTAPE2s4FwdaEHwOSb5zNvWngBoC/t4M5IaRJ6riDUds1rV6EQfcWozLJno+b oKOAhDX46z56DhSnUVhJhBoYf5RCCc2EfJBZS/3tKE+i2RGF+3JrQxPeTqC0dh5sNeeBxGxlkRQJ8 aY0O0249QFTAKOx0ofNRMdkHNggVLGomGrKAgy865MaOeJX1jHX0aYMAIEqGOKm3l8uZfFbd8k0Pl xYM0ew4hvrlDHNzD6UUVMeesxYMeDLXL8Q9mJ/aqwq0J9rZePExARsm43bOQeQCGpoPHopygQsuGD jkqQCRpw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oYjK3-002nPF-JK; Thu, 15 Sep 2022 07:30:07 +0000 Received: from madras.collabora.co.uk ([46.235.227.172]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oYjFH-002j73-QE; Thu, 15 Sep 2022 07:25:14 +0000 Received: from IcarusMOD.eternityproject.eu (2-237-20-237.ip236.fastwebnet.it [2.237.20.237]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kholk11) by madras.collabora.co.uk (Postfix) with ESMTPSA id A469C6601FC7; Thu, 15 Sep 2022 08:25:09 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1663226710; bh=78egXpcwYI0LobAOtW6zrOMH4zDX0mRd/unB/BTkHWw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CcqqYUxd23wXDO/PMP8P6pVxTGqgIjbg8z3+BjTYLRW2FTWRiL+2EHxxwgMLA3xrQ WFYcsBZipLCSHQH7lFEEQHD9gGSaGX26S55KaS+z+C3JikynwGn4yNhP3YLJbobcsS Z4kUG/lvZHwGvuR6753SXtR1ScX3fcJH1CrVw8e5x2fLtyJHaikVA8ZwtYrDj9mQQv qr084HTM9O1TBoKYCatkqxuk8lYj5ih04h3lX1CV7wwdUi121d3W4s6DpF/Z53Wzrr 3Q+kjdFiOpeZ6SeIG7bnHYKaeV3v3xlf21Dyp641hSUGp8MG8T66AIlo571mVoYLH4 Mzw8Yw7aX9ilg== From: AngeloGioacchino Del Regno To: matthias.bgg@gmail.com Cc: mturquette@baylibre.com, sboyd@kernel.org, angelogioacchino.delregno@collabora.com, wenst@chromium.org, miles.chen@mediatek.com, rex-bc.chen@mediatek.com, nfraprado@collabora.com, chun-jie.chen@mediatek.com, jose.exposito89@gmail.com, drinkcat@chromium.org, weiyi.lu@mediatek.com, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org Subject: [PATCH v2 04/10] clk: mediatek: mt8183: Add clk mux notifier for MFG mux Date: Thu, 15 Sep 2022 09:24:52 +0200 Message-Id: <20220915072458.18232-5-angelogioacchino.delregno@collabora.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220915072458.18232-1-angelogioacchino.delregno@collabora.com> References: <20220915072458.18232-1-angelogioacchino.delregno@collabora.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220915_002512_129464_2CEB8554 X-CRM114-Status: GOOD ( 17.50 ) 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 From: Chen-Yu Tsai When the MFG PLL clock, which is upstream of the MFG clock, is changed, the downstream clock and consumers need to be switched away from the PLL over to a stable clock to avoid glitches. This is done through the use of the newly added clk mux notifier. The notifier is set on the mux itself instead of the upstream PLL, but in practice this works, as the rate change notifitcations are propogated throughout the sub-tree hanging off the PLL. Just before rate changes, the MFG mux is temporarily and transparently switched to the 26 MHz main crystal. After the rate change, the mux is switched back. Signed-off-by: Chen-Yu Tsai [Angelo: Rebased to assign clk_ops in mtk_mux_nb] Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: AngeloGioacchino Del Regno Reviewed-by: Miles Chen --- drivers/clk/mediatek/clk-mt8183.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/clk/mediatek/clk-mt8183.c b/drivers/clk/mediatek/clk-mt8183.c index 8512101e1189..1860a35a723a 100644 --- a/drivers/clk/mediatek/clk-mt8183.c +++ b/drivers/clk/mediatek/clk-mt8183.c @@ -1198,10 +1198,33 @@ static void clk_mt8183_top_init_early(struct device_node *node) CLK_OF_DECLARE_DRIVER(mt8183_topckgen, "mediatek,mt8183-topckgen", clk_mt8183_top_init_early); +/* Register mux notifier for MFG mux */ +static int clk_mt8183_reg_mfg_mux_notifier(struct device *dev, struct clk *clk) +{ + struct mtk_mux_nb *mfg_mux_nb; + int i; + + mfg_mux_nb = devm_kzalloc(dev, sizeof(*mfg_mux_nb), GFP_KERNEL); + if (!mfg_mux_nb) + return -ENOMEM; + + for (i = 0; i < ARRAY_SIZE(top_muxes); i++) + if (top_muxes[i].id == CLK_TOP_MUX_MFG) + break; + if (i == ARRAY_SIZE(top_muxes)) + return -EINVAL; + + mfg_mux_nb->ops = top_muxes[i].ops; + mfg_mux_nb->bypass_index = 0; /* Bypass to 26M crystal */ + + return devm_mtk_clk_mux_notifier_register(dev, clk, mfg_mux_nb); +} + static int clk_mt8183_top_probe(struct platform_device *pdev) { void __iomem *base; struct device_node *node = pdev->dev.of_node; + int ret; base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(base)) @@ -1227,6 +1250,11 @@ static int clk_mt8183_top_probe(struct platform_device *pdev) mtk_clk_register_gates(node, top_clks, ARRAY_SIZE(top_clks), top_clk_data); + ret = clk_mt8183_reg_mfg_mux_notifier(&pdev->dev, + top_clk_data->hws[CLK_TOP_MUX_MFG]->clk); + if (ret) + return ret; + return of_clk_add_hw_provider(node, of_clk_hw_onecell_get, top_clk_data); }