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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3EF2C433EF for ; Mon, 25 Jul 2022 09:07:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234492AbiGYJHd (ORCPT ); Mon, 25 Jul 2022 05:07:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230177AbiGYJHa (ORCPT ); Mon, 25 Jul 2022 05:07:30 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE88C101DA; Mon, 25 Jul 2022 02:07:28 -0700 (PDT) Received: from [192.168.1.100] (2-237-20-237.ip236.fastwebnet.it [2.237.20.237]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) (Authenticated sender: kholk11) by madras.collabora.co.uk (Postfix) with ESMTPSA id 8899066015E7; Mon, 25 Jul 2022 10:07:26 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1658740047; bh=uBO/pkzkv5EBZYyQnsx8/L7C7pGHaycXjjQey8xXLe4=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=QbtCyY/TkCm/cZ6AZqWzL7/QMYs2ImlWgUzVxfDiic5PcKm8bW9KeO+u+AdbMM+Z5 bI0DjNsw21DmjykhDxvsLDyL1ImWvZ3OX2VSLVeSLlAM5D5uslVqbPAImGNKuZhzMf KetO4iahmMfcG0fIOg9u+5J0dbyU2UXGs6FSJn54KQ+gqrvaEasYO8sUe9uotVNFkb G72Aby95gW0LR8kpNE0tlQlRlmQv4Ulnzu48hz39lC8Tct1N1XO7Dk9CLcjrnvtun3 xfll+2wTR+urIfDaTR5MdkiKhFzVMVuK1q5YVk/ROibH5h5QwLFEQ0brJiHvTjaOVQ CUnU9FPjpDKog== Message-ID: <59d9e674-2021-b02e-4ec8-aee8a118a96d@collabora.com> Date: Mon, 25 Jul 2022 11:07:23 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH v2 3/4] soc: mediatek: add support of MTK_SCPD_STRICT_BUSP cap Content-Language: en-US To: Markus Schneider-Pargmann , Rob Herring , Krzysztof Kozlowski , Matthias Brugger , Weiyi Lu Cc: Fabien Parent , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Alexandre Bailon , Fabien Parent References: <20220725081853.1636444-1-msp@baylibre.com> <20220725081853.1636444-4-msp@baylibre.com> From: AngeloGioacchino Del Regno In-Reply-To: <20220725081853.1636444-4-msp@baylibre.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 25/07/22 10:18, Markus Schneider-Pargmann ha scritto: > From: Alexandre Bailon > > This adds support for MTK_SCPD_STRICT_BUSP capability. It is a strict > bus protection policy that requires the bus protection to be disabled > before accessing the bus. > This is required by the mt8365, for the MM power domain. > > Signed-off-by: Alexandre Bailon > Signed-off-by: Fabien Parent > Signed-off-by: Markus Schneider-Pargmann > --- > > Notes: > Changes in v2: > - Fixup error handling path. > > drivers/soc/mediatek/mtk-pm-domains.c | 29 +++++++++++++++++++++++---- > drivers/soc/mediatek/mtk-pm-domains.h | 1 + > 2 files changed, 26 insertions(+), 4 deletions(-) > > diff --git a/drivers/soc/mediatek/mtk-pm-domains.c b/drivers/soc/mediatek/mtk-pm-domains.c > index d0eae2227813..94ca8981f45e 100644 > --- a/drivers/soc/mediatek/mtk-pm-domains.c > +++ b/drivers/soc/mediatek/mtk-pm-domains.c > @@ -240,6 +240,7 @@ static int scpsys_power_on(struct generic_pm_domain *genpd) > struct scpsys *scpsys = pd->scpsys; > bool tmp; > int ret; > + bool strict_busprotect; > > ret = scpsys_regulator_enable(pd->supply); > if (ret) > @@ -263,9 +264,18 @@ static int scpsys_power_on(struct generic_pm_domain *genpd) > regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ISO_BIT); > regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_RST_B_BIT); > > - ret = clk_bulk_prepare_enable(pd->num_subsys_clks, pd->subsys_clks); > - if (ret) > - goto err_pwr_ack; > + /* > + * In few Mediatek platforms(e.g. MT6779), the bus protect policy is > + * stricter, which leads to bus protect release must be prior to bus > + * access. > + */ > + strict_busprotect = MTK_SCPD_CAPS(pd, MTK_SCPD_STRICT_BUSP); > + if (!strict_busprotect) { Please directly check for MTK_SCPD_CAPS, you don't really need that bool variable, not even for performance... and it fits just fine in one line, even. if (!MTK_SCPD_CAPS(pd, MTK_SCPD_STRICT_BUS_PROTECTION)) { > + ret = clk_bulk_prepare_enable(pd->num_subsys_clks, > + pd->subsys_clks); > + if (ret) > + goto err_pwr_ack; > + } > > ret = scpsys_sram_enable(pd); > if (ret < 0) > @@ -275,12 +285,23 @@ static int scpsys_power_on(struct generic_pm_domain *genpd) > if (ret < 0) > goto err_disable_sram; > > + if (strict_busprotect) { if (MTK_SCPD_CAPS(pd, MTK_SCPD_STRICT_BUS_PROTECTION)) { > + ret = clk_bulk_prepare_enable(pd->num_subsys_clks, > + pd->subsys_clks); > + if (ret) > + goto err_enable_bus_protect; > + } > + > return 0; > > +err_enable_bus_protect: For human readability purposes (and paranoidly preventing future mistakes), I'd add a check for the strict bus protection cap here too. > + scpsys_bus_protect_enable(pd); > err_disable_sram: > scpsys_sram_disable(pd); > err_disable_subsys_clks: > - clk_bulk_disable_unprepare(pd->num_subsys_clks, pd->subsys_clks); > + if (!strict_busprotect) > + clk_bulk_disable_unprepare(pd->num_subsys_clks, > + pd->subsys_clks); > err_pwr_ack: > clk_bulk_disable_unprepare(pd->num_clks, pd->clks); > err_reg: > diff --git a/drivers/soc/mediatek/mtk-pm-domains.h b/drivers/soc/mediatek/mtk-pm-domains.h > index e788d6bdde9d..a50cfb926d22 100644 > --- a/drivers/soc/mediatek/mtk-pm-domains.h > +++ b/drivers/soc/mediatek/mtk-pm-domains.h > @@ -8,6 +8,7 @@ > #define MTK_SCPD_SRAM_ISO BIT(2) > #define MTK_SCPD_KEEP_DEFAULT_OFF BIT(3) > #define MTK_SCPD_DOMAIN_SUPPLY BIT(4) > +#define MTK_SCPD_STRICT_BUSP BIT(5) MTK_SCPD_STRICT_BUS_PROTECTION is a bit more human readable. > #define MTK_SCPD_CAPS(_scpd, _x) ((_scpd)->data->caps & (_x)) > > #define SPM_VDE_PWR_CON 0x0210 Regards, Angelo