From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 490AF629FD; Tue, 20 Feb 2024 11:03:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708426984; cv=none; b=alUaowNew/1adYUnakUVtIkiMrKhoAHUjSIWPo4QrHuRapU8D0IuK8F3L31TJeCUaCizcJBS8bHZrOCpK14KNvbLs4NSTmO1dQgFmnkl5dtCOnykSqaK9L78shD8qgxgnE7iw1DDqkDBE9cyVh9Ek4EW++Lbx01jI6BKWclXGa0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708426984; c=relaxed/simple; bh=zuvLddHIXbqnQ9+Zwy+M4L650QAJdwFPOIroz3/ec9o=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=nu4GqVASipKVT2vbxDbHJOfYlP6ZeGns2H4Ex5uaO5/VE+11tiXNtufkG67pDgpLk23cDrFfK7z+Ei7IxZY9xjTUBZaneep471oNrfZG0bX0j7OxFhB56kBZ2pX4YlH0iWVS/AvDBd+HKVzkogg2b5vGgekLx4kF3hQE9oSw5lM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.231]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4TfGcM5KXGz6K6QG; Tue, 20 Feb 2024 18:58:59 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id 18AFD140B54; Tue, 20 Feb 2024 19:02:59 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Tue, 20 Feb 2024 11:02:58 +0000 Date: Tue, 20 Feb 2024 11:02:56 +0000 From: Jonathan Cameron To: CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: Re: [RFC PATCH v6 01/12] cxl/mbox: Add GET_SUPPORTED_FEATURES mailbox command Message-ID: <20240220110256.00001586@Huawei.com> In-Reply-To: <20240215111455.1462-2-shiju.jose@huawei.com> References: <20240215111455.1462-1-shiju.jose@huawei.com> <20240215111455.1462-2-shiju.jose@huawei.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: lhrpeml500003.china.huawei.com (7.191.162.67) To lhrpeml500005.china.huawei.com (7.191.163.240) On Thu, 15 Feb 2024 19:14:43 +0800 wrote: > From: Shiju Jose >=20 > Add support for GET_SUPPORTED_FEATURES mailbox command. >=20 > CXL spec 3.1 section 8.2.9.6 describes optional device specific features. > CXL devices supports features with changeable attributes. > Get Supported Features retrieves the list of supported device specific > features. The settings of a feature can be retrieved using Get Feature > and optionally modified using Set Feature. >=20 > Signed-off-by: Shiju Jose Hi Shiju, Some comment inline. Mostly just naming suggestions. Actual functionality looks good to me. > --- > drivers/cxl/core/mbox.c | 23 +++++++++++++++ > drivers/cxl/cxlmem.h | 62 +++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 85 insertions(+) >=20 > diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c > index 27166a411705..191f51f3df0e 100644 > --- a/drivers/cxl/core/mbox.c > +++ b/drivers/cxl/core/mbox.c > @@ -1290,6 +1290,29 @@ int cxl_set_timestamp(struct cxl_memdev_state *mds) > } > EXPORT_SYMBOL_NS_GPL(cxl_set_timestamp, CXL); > =20 > +int cxl_get_supported_features(struct cxl_memdev_state *mds, > + struct cxl_mbox_get_supp_feats_in *pi, > + void *feats_out) Odd indent. Align the later lines with s of struct Comments on input types in header below. > +{ > + struct cxl_mbox_cmd mbox_cmd; > + int rc; > + > + mbox_cmd =3D (struct cxl_mbox_cmd) { > + .opcode =3D CXL_MBOX_OP_GET_SUPPORTED_FEATURES, > + .size_in =3D sizeof(*pi), > + .payload_in =3D pi, > + .size_out =3D le32_to_cpu(pi->count), > + .payload_out =3D feats_out, > + .min_out =3D sizeof(struct cxl_mbox_get_supp_feats_out), feats_out should be typed, in which case this becomes sizeof(*feats_out) > + }; > + rc =3D cxl_internal_send_cmd(mds, &mbox_cmd); > + if (rc < 0) > + return rc; > + > + return 0; > +} > +EXPORT_SYMBOL_NS_GPL(cxl_get_supported_features, CXL); > + > int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len, > struct cxl_region *cxlr) > { > diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h > index 5303d6942b88..23e4d98b9bae 100644 > --- a/drivers/cxl/cxlmem.h > +++ b/drivers/cxl/cxlmem.h > @@ -529,6 +529,7 @@ enum cxl_opcode { > CXL_MBOX_OP_SET_TIMESTAMP =3D 0x0301, > CXL_MBOX_OP_GET_SUPPORTED_LOGS =3D 0x0400, > CXL_MBOX_OP_GET_LOG =3D 0x0401, > + CXL_MBOX_OP_GET_SUPPORTED_FEATURES =3D 0x0500, > CXL_MBOX_OP_IDENTIFY =3D 0x4000, > CXL_MBOX_OP_GET_PARTITION_INFO =3D 0x4100, > CXL_MBOX_OP_SET_PARTITION_INFO =3D 0x4101, > @@ -698,6 +699,64 @@ struct cxl_mbox_set_timestamp_in { > =20 > } __packed; > =20 > +/* Get Supported Features CXL 3.1 Spec 8.2.9.6.1 */ > +/* > + * Get Supported Features input payload > + * CXL rev 3.1 section 8.2.9.6.1 Table 8-95 > + */ > +struct cxl_mbox_get_supp_feats_in { > + __le32 count; > + __le16 start_index; > + u16 reserved; =46rom a local style point of view using a u16 for reserved is a new style choice - best to avoid that - most common option looks to be u8 rsvd[2]; > +} __packed; > + > +/* > + * Get Supported Features Supported Feature Entry > + * CXL rev 3.1 section 8.2.9.6.1 Table 8-97 > + */ > +/* Supported Feature Entry : Payload out attribute flags */ > +#define CXL_FEAT_ENTRY_FLAG_CHANGABLE BIT(0) > +#define CXL_FEAT_ENTRY_FLAG_DEEPEST_RESET_PERSISTENCE_MASK GENMASK(3, 1) > +#define CXL_FEAT_ENTRY_FLAG_PERSIST_ACROSS_FIRMWARE_UPDATE BIT(4) > +#define CXL_FEAT_ENTRY_FLAG_SUPPORT_DEFAULT_SELECTION BIT(5) > +#define CXL_FEAT_ENTRY_FLAG_SUPPORT_SAVED_SELECTION BIT(6) > + > +enum cxl_feat_attr_value_persistence { > + CXL_FEAT_ATTR_VALUE_PERSISTENCE_NONE, > + CXL_FEAT_ATTR_VALUE_PERSISTENCE_CXL_RESET, > + CXL_FEAT_ATTR_VALUE_PERSISTENCE_HOT_RESET, > + CXL_FEAT_ATTR_VALUE_PERSISTENCE_WARM_RESET, > + CXL_FEAT_ATTR_VALUE_PERSISTENCE_COLD_RESET, > + CXL_FEAT_ATTR_VALUE_PERSISTENCE_MAX > +}; > + > +#define CXL_FEAT_ENTRY_FLAG_PERSISTENCE_ACROSS_FW_UPDATE_MASK BIT(4) Not sure there is benefit in defining mask for single bit fields. Or if there is don't define the value above. > +#define CXL_FEAT_ENTRY_FLAG_PERSIST_ACROSS_FIRMWARE_UPDATE BIT(4) Either is probably fine, just not both! > +#define CXL_FEAT_ENTRY_FLAG_PERSISTENCE_DEFAULT_SEL_SUPPORT_MASK BIT(5) > +#define CXL_FEAT_ENTRY_FLAG_PERSISTENCE_SAVED_SEL_SUPPORT_MASK BIT(6) > + > +struct cxl_mbox_supp_feat_entry { > + uuid_t uuid; > + __le16 feat_index; Given it's in a feat entry, could drop 'feat' as redundant info. __le16 index; __le16 get_size; etc > + __le16 get_feat_size; > + __le16 set_feat_size; > + __le32 attr_flags; > + u8 get_feat_version; > + u8 set_feat_version; > + __le16 set_feat_effects; > + u8 rsvd[18]; > +} __packed; > + > +/* > + * Get Supported Features output payload > + * CXL rev 3.1 section 8.2.9.6.1 Table 8-96 > + */ > +struct cxl_mbox_get_supp_feats_out { > + __le16 entries; > + __le16 nsuppfeats_dev; Probably don't need the _dev postfix. Command being sent to a device so that doesn't add much. I looked at naming in similar cases. For mailbox clear we have nr_recs, so perhaps nr_supported ? > + u32 reserved; u8 rsvd[4]; as above - match the local syle. > + struct cxl_mbox_supp_feat_entry feat_entries[]; > +} __packed; > + > /* Get Poison List CXL 3.0 Spec 8.2.9.8.4.1 */ > struct cxl_mbox_poison_in { > __le64 offset; > @@ -829,6 +888,9 @@ void cxl_event_trace_record(const struct cxl_memdev *= cxlmd, > enum cxl_event_type event_type, > const uuid_t *uuid, union cxl_event *evt); > int cxl_set_timestamp(struct cxl_memdev_state *mds); > +int cxl_get_supported_features(struct cxl_memdev_state *mds, > + struct cxl_mbox_get_supp_feats_in *pi, > + void *feats_out); Don't use a void * for that output data. It should be a struct cxl_mbox_get_supp_feats_out * For the input, the other similar functions are providing parameters directly, not wrapped up in a structure. Easy enough to do that here as well as we only need u32 count, u16 start_index instead of pi > int cxl_poison_state_init(struct cxl_memdev_state *mds); > int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len, > struct cxl_region *cxlr);