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 381EDC7EE45 for ; Mon, 12 Jun 2023 04:46:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233866AbjFLEqG (ORCPT ); Mon, 12 Jun 2023 00:46:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235691AbjFLEpg (ORCPT ); Mon, 12 Jun 2023 00:45:36 -0400 Received: from mail-oo1-xc2a.google.com (mail-oo1-xc2a.google.com [IPv6:2607:f8b0:4864:20::c2a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B0F91A5 for ; Sun, 11 Jun 2023 21:45:33 -0700 (PDT) Received: by mail-oo1-xc2a.google.com with SMTP id 006d021491bc7-55b3fe7a788so2521385eaf.2 for ; Sun, 11 Jun 2023 21:45:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1686545133; x=1689137133; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=B8PjX/aOXa3D/DnSIe/K9/s+OsmRXVqzcni+yFefbXo=; b=SiM+aG3JrJbkzgBR0VBVug7fBxoWkJMWBYaON6CcIT1cIB2IMsknprPYSLSVZtGt6a K/p6m/eBIsDmlzxNPkCe/gneRcrBLANYXoOZW9AUOkwmYSagXnnlNWJz7z2zYr4JcLdk E6Gf7ia1Mx76DK7wwOY9f1xRXHya2IQuaZMXo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686545133; x=1689137133; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=B8PjX/aOXa3D/DnSIe/K9/s+OsmRXVqzcni+yFefbXo=; b=KMt4GhVnzy5H3GK0CrJDtvX+HUJSG0VtOuGYcqRlDcmPRMgBbZYVMpNXRKZO0sMYH9 xi8GRUgP4je5HIC4bJ2geHafQ45axivDJr747sogl1AWoICpFVEv8TcUKpdIp8zW5R1M v3Mfzf7vklqDouPntVFmx2Jrmo7lz2DtBPBSKrZvhb4pTtlasun4CPpA9+3F2UmegNaY I+nObGNPQUZk0QTLnhaviU7XWZMEgrO++OOdzgALFI+QcaA5x+0SroG74QsV+PRH7Etg 0si7N6s5pXRCUBXSu77fJaYNN8QKzR8zBeZy8KA8gOUlMZCzMGdysgzm2inQH05k/ekG +QeQ== X-Gm-Message-State: AC+VfDzRoxps9aXrYnSJN1yOS/zBjM7iVhzzIqX5gEzAmolP7KSL2Qok biB2oqd6qf56w6tfPdu2Ri4xaArmdhP6Pg1KPcnMaQ== X-Google-Smtp-Source: ACHHUZ59qM3qtQdWanFUYraxh4tCd+HRdsqwvAeH16+bcYuPxn5Z5kNdapzrWdVRi/Y9P+z48jlOBEOHfRnsOZ/ruBI= X-Received: by 2002:aca:c41:0:b0:39b:d6f1:36e5 with SMTP id i1-20020aca0c41000000b0039bd6f136e5mr3313176oiy.50.1686545132808; Sun, 11 Jun 2023 21:45:32 -0700 (PDT) MIME-Version: 1.0 References: <20230609083009.2822259-1-wenst@chromium.org> <20230609083009.2822259-5-wenst@chromium.org> In-Reply-To: From: Chen-Yu Tsai Date: Mon, 12 Jun 2023 12:45:21 +0800 Message-ID: Subject: Re: [PATCH 4/9] regulator: mt6358: Drop *_SSHUB regulators To: AngeloGioacchino Del Regno Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Mark Brown , Liam Girdwood , Matthias Brugger , Gene Chen , Johnson Wang , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Fri, Jun 9, 2023 at 5:03=E2=80=AFPM AngeloGioacchino Del Regno wrote: > > Il 09/06/23 10:30, Chen-Yu Tsai ha scritto: > > The *_SSHUB regulators are actually alternate configuration interfaces > > for their non *_SSHUB counterparts. They are not separate regulator > > outputs. These registers are intended for the companion processor to > > use to configure the power rails while the main processor is sleeping. > > They are not intended for the main operating system to use. > > > > Since they are not real outputs they shouldn't be modeled separately. > > Remove them. Luckily no device tree actually uses them. > > > > I'm not sure that MT6358/6366 are used only on Chromebook SoCs, and that = this SSHUB > mechanism (companion processor) is the same across all firmwares. AFAICT from Internet sources there's also the MT6771 and MT6781, which are used on some phones. But what part are you concerned about? The upstream regulator driver does not actually have any code to switch to/from normal operation and SSHUB mode. In a downstream kernel I found that the SSHUB mode is only used if SCP is doing DVFS [1]. In that same kernel, the regulator driver [2] doesn't even list the *_SSHUB versions. So if SCP DVFS is used, the regulator driver has no idea what's going on, and can't interfere either, which I think is actually a good thing. Only one side should have complete control of one output. ChenYu [1] https://github.com/nokia-dev/android_kernel_nokia_mt6771/blob/android-9= .0/drivers/misc/mediatek/scp/mt6771/scp_dvfs.c [2] https://github.com/nokia-dev/android_kernel_nokia_mt6771/blob/android-9= .0/drivers/misc/mediatek/pmic/mt6358/v1/regulator_codegen.c > I'd like someone from MediaTek to confirm that this is valid for both Chr= omebook > and Smartphone firmwares. > > Regards, > Angelo > > > Signed-off-by: Chen-Yu Tsai > > --- > > drivers/regulator/mt6358-regulator.c | 14 -------------- > > include/linux/regulator/mt6358-regulator.h | 4 ---- > > 2 files changed, 18 deletions(-) > > > > diff --git a/drivers/regulator/mt6358-regulator.c b/drivers/regulator/m= t6358-regulator.c > > index faf6b0757019..946a251a8b3a 100644 > > --- a/drivers/regulator/mt6358-regulator.c > > +++ b/drivers/regulator/mt6358-regulator.c > > @@ -505,9 +505,6 @@ static struct mt6358_regulator_info mt6358_regulato= rs[] =3D { > > MT6358_BUCK("buck_vcore", VCORE, 500000, 1293750, 6250, > > buck_volt_range1, 0x7f, MT6358_BUCK_VCORE_DBG0, 0x7f, > > MT6358_VCORE_VGPU_ANA_CON0, 1), > > - MT6358_BUCK("buck_vcore_sshub", VCORE_SSHUB, 500000, 1293750, 625= 0, > > - buck_volt_range1, 0x7f, MT6358_BUCK_VCORE_SSHUB_ELR0,= 0x7f, > > - MT6358_VCORE_VGPU_ANA_CON0, 1), > > MT6358_BUCK("buck_vpa", VPA, 500000, 3650000, 50000, > > buck_volt_range3, 0x3f, MT6358_BUCK_VPA_DBG0, 0x3f, > > MT6358_VPA_ANA_CON0, 3), > > @@ -583,10 +580,6 @@ static struct mt6358_regulator_info mt6358_regulat= ors[] =3D { > > MT6358_LDO1("ldo_vsram_others", VSRAM_OTHERS, 500000, 1293750, 62= 50, > > buck_volt_range1, MT6358_LDO_VSRAM_OTHERS_DBG0, 0x7f0= 0, > > MT6358_LDO_VSRAM_CON2, 0x7f), > > - MT6358_LDO1("ldo_vsram_others_sshub", VSRAM_OTHERS_SSHUB, 500000, > > - 1293750, 6250, buck_volt_range1, > > - MT6358_LDO_VSRAM_OTHERS_SSHUB_CON1, 0x7f, > > - MT6358_LDO_VSRAM_OTHERS_SSHUB_CON1, 0x7f), > > MT6358_LDO1("ldo_vsram_gpu", VSRAM_GPU, 500000, 1293750, 6250, > > buck_volt_range1, MT6358_LDO_VSRAM_GPU_DBG0, 0x7f00, > > MT6358_LDO_VSRAM_CON3, 0x7f), > > @@ -603,9 +596,6 @@ static struct mt6358_regulator_info mt6366_regulato= rs[] =3D { > > MT6366_BUCK("buck_vcore", VCORE, 500000, 1293750, 6250, > > buck_volt_range1, 0x7f, MT6358_BUCK_VCORE_DBG0, 0x7f, > > MT6358_VCORE_VGPU_ANA_CON0, 1), > > - MT6366_BUCK("buck_vcore_sshub", VCORE_SSHUB, 500000, 1293750, 625= 0, > > - buck_volt_range1, 0x7f, MT6358_BUCK_VCORE_SSHUB_ELR0,= 0x7f, > > - MT6358_VCORE_VGPU_ANA_CON0, 1), > > MT6366_BUCK("buck_vpa", VPA, 500000, 3650000, 50000, > > buck_volt_range3, 0x3f, MT6358_BUCK_VPA_DBG0, 0x3f, > > MT6358_VPA_ANA_CON0, 3), > > @@ -670,10 +660,6 @@ static struct mt6358_regulator_info mt6366_regulat= ors[] =3D { > > MT6366_LDO1("ldo_vsram_others", VSRAM_OTHERS, 500000, 1293750, 62= 50, > > buck_volt_range1, MT6358_LDO_VSRAM_OTHERS_DBG0, 0x7f0= 0, > > MT6358_LDO_VSRAM_CON2, 0x7f), > > - MT6366_LDO1("ldo_vsram_others_sshub", VSRAM_OTHERS_SSHUB, 500000, > > - 1293750, 6250, buck_volt_range1, > > - MT6358_LDO_VSRAM_OTHERS_SSHUB_CON1, 0x7f, > > - MT6358_LDO_VSRAM_OTHERS_SSHUB_CON1, 0x7f), > > MT6366_LDO1("ldo_vsram_gpu", VSRAM_GPU, 500000, 1293750, 6250, > > buck_volt_range1, MT6358_LDO_VSRAM_GPU_DBG0, 0x7f00, > > MT6358_LDO_VSRAM_CON3, 0x7f), > > diff --git a/include/linux/regulator/mt6358-regulator.h b/include/linux= /regulator/mt6358-regulator.h > > index a4307cd9edd6..c71a6a9fce7a 100644 > > --- a/include/linux/regulator/mt6358-regulator.h > > +++ b/include/linux/regulator/mt6358-regulator.h > > @@ -47,8 +47,6 @@ enum { > > MT6358_ID_VLDO28, > > MT6358_ID_VAUD28, > > MT6358_ID_VSIM2, > > - MT6358_ID_VCORE_SSHUB, > > - MT6358_ID_VSRAM_OTHERS_SSHUB, > > MT6358_ID_RG_MAX, > > }; > > > > @@ -88,8 +86,6 @@ enum { > > MT6366_ID_VMC, > > MT6366_ID_VAUD28, > > MT6366_ID_VSIM2, > > - MT6366_ID_VCORE_SSHUB, > > - MT6366_ID_VSRAM_OTHERS_SSHUB, > > MT6366_ID_RG_MAX, > > }; > > >