From patchwork Wed Jun 14 10:22:17 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Konrad Dybcio X-Patchwork-Id: 692685 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 33311EB64DD for ; Wed, 14 Jun 2023 10:22:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243620AbjFNKWp (ORCPT ); Wed, 14 Jun 2023 06:22:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234949AbjFNKWi (ORCPT ); Wed, 14 Jun 2023 06:22:38 -0400 Received: from mail-lj1-x236.google.com (mail-lj1-x236.google.com [IPv6:2a00:1450:4864:20::236]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96AF61BF3 for ; Wed, 14 Jun 2023 03:22:27 -0700 (PDT) Received: by mail-lj1-x236.google.com with SMTP id 38308e7fff4ca-2b349703e90so6003141fa.0 for ; Wed, 14 Jun 2023 03:22:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1686738145; x=1689330145; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=UEM3N0iLIlvYLepw85JsPFibfyRzMkZ98OPjRwmkvbs=; b=UrbFlgODVPmj2NGdwjbJRN5t/sB1AfaciGH68h64gdEejWHI3SD3zK8hGzT1VGsHuc Xx+z+e1I9qjCkj2StftG05xScivv+lWx3n41s9vEVxgE6CNNvtjCnIrT1wUSeE8sZMIy LM9elia3GePns6kaWAfbSjsKhsdmZ+cm+XGmvUSyUB79k1eEtD7iK84Dt1K+JQOc9B87 gM6zOHZpYr4qT11kvmm3PpxFgmJL8fZG+vDczAtreBIclrmX49LzF+cqqXYDka1/uwht zZIeb+6ksWaTk5cKtAaTYfMT8ukPLWo2TlI3SuhhL1Sx2LpMao643lmxFz7/Oe7f+f9n neIg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686738145; x=1689330145; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=UEM3N0iLIlvYLepw85JsPFibfyRzMkZ98OPjRwmkvbs=; b=fP3qOygcQq3K+Jrat2nYRzvMpqpz+oaW20YtDElMAMzbDPAmo6hezL1TFACxaFHEMN LPcUVoAS8Svae6s/MctlurdGt9FXelw28asbrMYH4DvAOSPjnayNGOh/pqRZClTcRI49 mqcJzKeaTvLkC4cXqN6MgFggui+uReeGRcqZOH5QaY1CzUZgYjvkLmjU9pop3PR1hPmR lQ9FKeAGHHVdxPgeJenDyF3fNNapcMINgtOaygVQXbJZ8CCKX9hvBDuXdnkJldlHnq1s I7c3rYjEcZeNV5xtHu1Xd1QbInyTJbHG3eS8STaxGh9eBu28xfJCO6AwHuSNhvldpxqh gziQ== X-Gm-Message-State: AC+VfDxgGaXvINIZhIaSUTeuiCTSotJ8oeTfOgySaeuM1NOsXcU/id+D sjCN/As9jBxcxkif2sEayw5/qA== X-Google-Smtp-Source: ACHHUZ6QIgny4qx99n2wOMJLyHIrxll5PjxQICjC+F7POpODJ+0rfetBkmTUy/GzGbRQRyZ4lnoHNQ== X-Received: by 2002:a2e:7208:0:b0:2b1:eb9e:20df with SMTP id n8-20020a2e7208000000b002b1eb9e20dfmr5951905ljc.17.1686738145613; Wed, 14 Jun 2023 03:22:25 -0700 (PDT) Received: from [192.168.1.101] (abyj190.neoplus.adsl.tpnet.pl. [83.9.29.190]) by smtp.gmail.com with ESMTPSA id m2-20020a2eb6c2000000b002b20d8f270asm2520057ljo.74.2023.06.14.03.22.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Jun 2023 03:22:25 -0700 (PDT) From: Konrad Dybcio Date: Wed, 14 Jun 2023 12:22:17 +0200 Subject: [PATCH v5 06/22] interconnect: qcom: icc-rpm: Introduce keep_alive MIME-Version: 1.0 Message-Id: <20230526-topic-smd_icc-v5-6-eeaa09d0082e@linaro.org> References: <20230526-topic-smd_icc-v5-0-eeaa09d0082e@linaro.org> In-Reply-To: <20230526-topic-smd_icc-v5-0-eeaa09d0082e@linaro.org> To: Andy Gross , Bjorn Andersson , Michael Turquette , Stephen Boyd , Georgi Djakov , Leo Yan , Evan Green , Rob Herring , Krzysztof Kozlowski , Conor Dooley Cc: Marijn Suijten , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-pm@vger.kernel.org, devicetree@vger.kernel.org, Konrad Dybcio , Dmitry Baryshkov X-Mailer: b4 0.12.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1686738135; l=3661; i=konrad.dybcio@linaro.org; s=20230215; h=from:subject:message-id; bh=g6kESh9vFn5cUExPwamnhleED6tFd+S7dtFe11cmEVE=; b=+5TX+IWvITvOPt3FKf80PLSfZpyEXg88Ruo8CN8uG442tDQftNEqI6MIJVm4RfvIrr5ZrEjJb Pyy9LVaNOsnCtkERlGg1opf2kH26p6NKEihhv9gZBKtDVHoKjOeOEUI X-Developer-Key: i=konrad.dybcio@linaro.org; a=ed25519; pk=iclgkYvtl2w05SSXO5EjjSYlhFKsJ+5OSZBjOkQuEms= Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The downstream kernel employs the concept of "keeping the bus alive" by voting for the minimum (XO/19.2MHz) rate at all times on certain (well, most) buses. This is a very important thing to have, as if we either have a lackluster/wrong DT that doesn't specify a (high enough) vote on a certain bus, we may lose access to the entire bus altogether. This is very apparent when we only start introducing interconnect support on a given platform and haven't yet introduced voting on all peripherals. The same can happen if we only have a single driver casting a vote on a certain bus and that driver exits/crashes/suspends. The keepalive vote is limited to the ACTIVE bucket, as keeping a permanent vote on the SLEEP one could prevent the platform from properly entering low power mode states. Introduce the very same concept, with a slight twist: the vendor kernel checks whether the rate is zero before setting the minimum vote, but that's rather silly, as in doing so we're at the mercy of CCF. Instead, explicitly clamp the rates to always be >= 19.2 MHz for providers with keep_alive=true. Reviewed-by: Dmitry Baryshkov Signed-off-by: Konrad Dybcio --- drivers/interconnect/qcom/icc-rpm.c | 10 ++++++++++ drivers/interconnect/qcom/icc-rpm.h | 3 +++ 2 files changed, 13 insertions(+) diff --git a/drivers/interconnect/qcom/icc-rpm.c b/drivers/interconnect/qcom/icc-rpm.c index 6acc7686ed38..863e8ba1daa2 100644 --- a/drivers/interconnect/qcom/icc-rpm.c +++ b/drivers/interconnect/qcom/icc-rpm.c @@ -50,6 +50,8 @@ #define NOC_QOS_MODE_FIXED_VAL 0x0 #define NOC_QOS_MODE_BYPASS_VAL 0x2 +#define ICC_BUS_CLK_MIN_RATE 19200000ULL + static int qcom_icc_set_qnoc_qos(struct icc_node *src) { struct icc_provider *provider = src->provider; @@ -380,6 +382,13 @@ static int qcom_icc_set(struct icc_node *src, struct icc_node *dst) do_div(rate, src_qn->buswidth); rate = min_t(u64, rate, LONG_MAX); + /* + * Downstream checks whether the requested rate is zero, but it makes little sense + * to vote for a value that's below the lower threshold, so let's not do so. + */ + if (bucket == QCOM_ICC_BUCKET_WAKE && qp->keep_alive) + rate = max(ICC_BUS_CLK_MIN_RATE, rate); + if (qp->bus_clk_rate[i] == rate) continue; @@ -453,6 +462,7 @@ int qnoc_probe(struct platform_device *pdev) for (i = 0; i < qp->num_bus_clks; i++) qp->bus_clks[i].id = bus_clocks[i]; + qp->keep_alive = desc->keep_alive; qp->type = desc->type; qp->qos_offset = desc->qos_offset; diff --git a/drivers/interconnect/qcom/icc-rpm.h b/drivers/interconnect/qcom/icc-rpm.h index ee705edf19dd..d2c04c400cad 100644 --- a/drivers/interconnect/qcom/icc-rpm.h +++ b/drivers/interconnect/qcom/icc-rpm.h @@ -33,6 +33,7 @@ enum qcom_icc_type { * @bus_clk_rate: bus clock rate in Hz * @bus_clks: the clk_bulk_data table of bus clocks * @intf_clks: a clk_bulk_data array of interface clocks + * @keep_alive: whether to always keep a minimum vote on the bus clocks * @is_on: whether the bus is powered on */ struct qcom_icc_provider { @@ -45,6 +46,7 @@ struct qcom_icc_provider { u64 bus_clk_rate[NUM_BUS_CLKS]; struct clk_bulk_data bus_clks[NUM_BUS_CLKS]; struct clk_bulk_data *intf_clks; + bool keep_alive; bool is_on; }; @@ -102,6 +104,7 @@ struct qcom_icc_desc { const char * const *bus_clocks; const char * const *intf_clocks; size_t num_intf_clocks; + bool keep_alive; bool no_clk_scaling; enum qcom_icc_type type; const struct regmap_config *regmap_cfg;