From patchwork Tue Jan 30 04:02:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kang Yang X-Patchwork-Id: 768851 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (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 5899133CE7 for ; Tue, 30 Jan 2024 04:03:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706587420; cv=none; b=UrqgTDOhreMEtIq9j6IvcMhBuvcqbSydZ3N0Kluw3Rsdq3nEN8Ss/dScgGIw2Oy4kSSuuv6GzWiKEBRQNlE1HXokQC4alJOFjS8BfYDV7JvdWJiyyAwRusfknJczvCWt/YAs0bUe3hKFjwF+8pCUKGwYnpSBbLA3RPhuO/QVN/E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706587420; c=relaxed/simple; bh=OxFgWY2B+Puz3x1TVEEDL2G+vlN9T/MhIb54dm1Wseo=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=h39Qz7PWbbfyiEQ6+k5KgkBtWMVEnJmefNxjDSxmpvndhlMKEq5dtXTg/dM3WHoCjh33Jz4BQRkW1TVqVDopZHpH/QM7S+iE2owHeq7vi05mbokDlcCI1vjt0PiOx9f4lj8OlnzfuEt1RAl8zJCOEo8hgypXGa9t7LK1OHwBPvY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=mOvG67Ju; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="mOvG67Ju" Received: from pps.filterd (m0279867.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 40U2x2ri005127; Tue, 30 Jan 2024 04:03:34 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s= qcppdkim1; bh=kq5ik4cqrFhCJBTGQsH4vVqTK/XNrLTJnrbauAxovqU=; b=mO vG67JuIA/SJzJTap1dYdpjnQLchqpUbkqrWSq/tkGErxauiFp4XwSZGmvw1klwzX Iu8gPljyx9BTxlt4rY4naYKykmNpBu00GL9P2WKnwf2RVn23gcbsEP9Qem+/utY6 fbiA1rBI27rd/iGLmyBYjcc812dDroiEholsAQpTDcQjrriLFb2xO52wS89A1WAX B0L/iZYCt518xIjSzsnOqeermvKd25TiFQtYHrEzT5RtZg896YyVACiYQ3baUv85 GDKCadtxxTLF1EM57kv4uuAYlOGkLjwyYGYKhkGaLrg2U9Iais/WAjX2GOCy8Uet Gck1hsNC8V+ddDWvVqdw== Received: from nalasppmta01.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3vxdwf9g5d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 30 Jan 2024 04:03:34 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 40U43Xer005133 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 30 Jan 2024 04:03:33 GMT Received: from yk-E5440.qca.qualcomm.com (10.80.80.8) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Mon, 29 Jan 2024 20:03:31 -0800 From: Kang Yang To: CC: , Subject: [PATCH v6 05/11] wifi: ath12k: implement handling of P2P NoA event Date: Tue, 30 Jan 2024 12:02:57 +0800 Message-ID: <20240130040303.370590-6-quic_kangyang@quicinc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240130040303.370590-1-quic_kangyang@quicinc.com> References: <20240130040303.370590-1-quic_kangyang@quicinc.com> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01b.na.qualcomm.com (10.47.209.197) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: 87IfZ2hURcavCLk7LzLq10zLWWXU4QBt X-Proofpoint-ORIG-GUID: 87IfZ2hURcavCLk7LzLq10zLWWXU4QBt X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-01-29_15,2024-01-29_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 mlxscore=0 bulkscore=0 malwarescore=0 clxscore=1015 spamscore=0 impostorscore=0 phishscore=0 mlxlogscore=999 priorityscore=1501 adultscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2401190000 definitions=main-2401300026 The NoA(Notice of Absence) attribute is used by the P2P Group Owner to signal its absence due to power save timing, concurrent operation, or off-channel scanning. It is also used in the P2P Presence Request-Response mechanism. The NoA attribute shall be present in the P2P IE in the beacon frames transmitted by a P2P Group Owner when a NoA schedule is being advertised, or when the CTWindow is non-zero. So add support to update P2P information after P2P GO is up through event WMI_P2P_NOA_EVENTID, and always put it in probe resp. Create p2p.c and p2p.h for P2P related functions and definitions. Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0.1-00029-QCAHKSWPL_SILICONZ-1 Signed-off-by: Kang Yang --- v6: no change. v5: no change. v4: no change. v3: use ath12k_ah_to_ar() to get ar. v2: add Tested-on tag of QCN9274. --- drivers/net/wireless/ath/ath12k/Makefile | 3 +- drivers/net/wireless/ath/ath12k/mac.c | 27 ++++- drivers/net/wireless/ath/ath12k/p2p.c | 142 +++++++++++++++++++++++ drivers/net/wireless/ath/ath12k/p2p.h | 23 ++++ drivers/net/wireless/ath/ath12k/wmi.c | 51 +++++++- drivers/net/wireless/ath/ath12k/wmi.h | 31 +++++ 6 files changed, 274 insertions(+), 3 deletions(-) create mode 100644 drivers/net/wireless/ath/ath12k/p2p.c create mode 100644 drivers/net/wireless/ath/ath12k/p2p.h diff --git a/drivers/net/wireless/ath/ath12k/Makefile b/drivers/net/wireless/ath/ath12k/Makefile index 62c52e733b5e..e296fe7f8d64 100644 --- a/drivers/net/wireless/ath/ath12k/Makefile +++ b/drivers/net/wireless/ath/ath12k/Makefile @@ -19,7 +19,8 @@ ath12k-y += core.o \ hw.o \ mhi.o \ pci.o \ - dp_mon.o + dp_mon.o \ + p2p.o ath12k-$(CONFIG_ATH12K_TRACING) += trace.o diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c index 1604597d8825..0cfcf297872d 100644 --- a/drivers/net/wireless/ath/ath12k/mac.c +++ b/drivers/net/wireless/ath/ath12k/mac.c @@ -5119,6 +5119,27 @@ static int ath12k_mac_mgmt_tx(struct ath12k *ar, struct sk_buff *skb, return 0; } +static void ath12k_mac_add_p2p_noa_ie(struct ath12k *ar, + struct ieee80211_vif *vif, + struct sk_buff *skb, + bool is_prb_rsp) +{ + struct ath12k_vif *arvif = ath12k_vif_to_arvif(vif); + + if (likely(!is_prb_rsp)) + return; + + spin_lock_bh(&ar->data_lock); + + if (arvif->u.ap.noa_data && + !pskb_expand_head(skb, 0, arvif->u.ap.noa_len, + GFP_ATOMIC)) + skb_put_data(skb, arvif->u.ap.noa_data, + arvif->u.ap.noa_len); + + spin_unlock_bh(&ar->data_lock); +} + static void ath12k_mac_op_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control, struct sk_buff *skb) @@ -5142,10 +5163,10 @@ static void ath12k_mac_op_tx(struct ieee80211_hw *hw, skb_cb->flags |= ATH12K_SKB_CIPHER_SET; } + is_prb_rsp = ieee80211_is_probe_resp(hdr->frame_control); if (info_flags & IEEE80211_TX_CTL_HW_80211_ENCAP) { skb_cb->flags |= ATH12K_SKB_HW_80211_ENCAP; } else if (ieee80211_is_mgmt(hdr->frame_control)) { - is_prb_rsp = ieee80211_is_probe_resp(hdr->frame_control); ret = ath12k_mac_mgmt_tx(ar, skb, is_prb_rsp); if (ret) { ath12k_warn(ar->ab, "failed to queue management frame %d\n", @@ -5155,6 +5176,10 @@ static void ath12k_mac_op_tx(struct ieee80211_hw *hw, return; } + /* This is case only for P2P_GO */ + if (vif->type == NL80211_IFTYPE_AP && vif->p2p) + ath12k_mac_add_p2p_noa_ie(ar, vif, skb, is_prb_rsp); + ret = ath12k_dp_tx(ar, arvif, skb); if (ret) { ath12k_warn(ar->ab, "failed to transmit frame %d\n", ret); diff --git a/drivers/net/wireless/ath/ath12k/p2p.c b/drivers/net/wireless/ath/ath12k/p2p.c new file mode 100644 index 000000000000..61e919b23b16 --- /dev/null +++ b/drivers/net/wireless/ath/ath12k/p2p.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: ISC +/* + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include +#include "core.h" +#include "mac.h" +#include "p2p.h" + +static void ath12k_p2p_noa_ie_fill(u8 *data, size_t len, + const struct ath12k_wmi_p2p_noa_info *noa) +{ + struct ieee80211_p2p_noa_attr *noa_attr; + u8 ctwindow = le32_get_bits(noa->noa_attr, WMI_P2P_NOA_INFO_CTWIN_TU); + bool oppps = le32_get_bits(noa->noa_attr, WMI_P2P_NOA_INFO_OPP_PS); + __le16 *noa_attr_len; + u16 attr_len; + u8 noa_descriptors = le32_get_bits(noa->noa_attr, + WMI_P2P_NOA_INFO_DESC_NUM); + int i; + + /* P2P IE */ + data[0] = WLAN_EID_VENDOR_SPECIFIC; + data[1] = len - 2; + data[2] = (WLAN_OUI_WFA >> 16) & 0xff; + data[3] = (WLAN_OUI_WFA >> 8) & 0xff; + data[4] = (WLAN_OUI_WFA >> 0) & 0xff; + data[5] = WLAN_OUI_TYPE_WFA_P2P; + + /* NOA ATTR */ + data[6] = IEEE80211_P2P_ATTR_ABSENCE_NOTICE; + noa_attr_len = (__le16 *)&data[7]; /* 2 bytes */ + noa_attr = (struct ieee80211_p2p_noa_attr *)&data[9]; + + noa_attr->index = le32_get_bits(noa->noa_attr, + WMI_P2P_NOA_INFO_INDEX); + noa_attr->oppps_ctwindow = ctwindow; + if (oppps) + noa_attr->oppps_ctwindow |= IEEE80211_P2P_OPPPS_ENABLE_BIT; + + for (i = 0; i < noa_descriptors; i++) { + noa_attr->desc[i].count = + __le32_to_cpu(noa->descriptors[i].type_count); + noa_attr->desc[i].duration = noa->descriptors[i].duration; + noa_attr->desc[i].interval = noa->descriptors[i].interval; + noa_attr->desc[i].start_time = noa->descriptors[i].start_time; + } + + attr_len = 2; /* index + oppps_ctwindow */ + attr_len += noa_descriptors * sizeof(struct ieee80211_p2p_noa_desc); + *noa_attr_len = __cpu_to_le16(attr_len); +} + +static size_t ath12k_p2p_noa_ie_len_compute(const struct ath12k_wmi_p2p_noa_info *noa) +{ + size_t len = 0; + + if (!(le32_get_bits(noa->noa_attr, WMI_P2P_NOA_INFO_DESC_NUM)) && + !(le32_get_bits(noa->noa_attr, WMI_P2P_NOA_INFO_OPP_PS))) + return 0; + + len += 1 + 1 + 4; /* EID + len + OUI */ + len += 1 + 2; /* noa attr + attr len */ + len += 1 + 1; /* index + oppps_ctwindow */ + len += le32_get_bits(noa->noa_attr, WMI_P2P_NOA_INFO_DESC_NUM) * + sizeof(struct ieee80211_p2p_noa_desc); + + return len; +} + +static void ath12k_p2p_noa_ie_assign(struct ath12k_vif *arvif, void *ie, + size_t len) +{ + struct ath12k *ar = arvif->ar; + + lockdep_assert_held(&ar->data_lock); + + kfree(arvif->u.ap.noa_data); + + arvif->u.ap.noa_data = ie; + arvif->u.ap.noa_len = len; +} + +static void __ath12k_p2p_noa_update(struct ath12k_vif *arvif, + const struct ath12k_wmi_p2p_noa_info *noa) +{ + struct ath12k *ar = arvif->ar; + void *ie; + size_t len; + + lockdep_assert_held(&ar->data_lock); + + ath12k_p2p_noa_ie_assign(arvif, NULL, 0); + + len = ath12k_p2p_noa_ie_len_compute(noa); + if (!len) + return; + + ie = kmalloc(len, GFP_ATOMIC); + if (!ie) + return; + + ath12k_p2p_noa_ie_fill(ie, len, noa); + ath12k_p2p_noa_ie_assign(arvif, ie, len); +} + +void ath12k_p2p_noa_update(struct ath12k_vif *arvif, + const struct ath12k_wmi_p2p_noa_info *noa) +{ + struct ath12k *ar = arvif->ar; + + spin_lock_bh(&ar->data_lock); + __ath12k_p2p_noa_update(arvif, noa); + spin_unlock_bh(&ar->data_lock); +} + +static void ath12k_p2p_noa_update_vdev_iter(void *data, u8 *mac, + struct ieee80211_vif *vif) +{ + struct ath12k_vif *arvif = ath12k_vif_to_arvif(vif); + struct ath12k_p2p_noa_arg *arg = data; + + if (arvif->vdev_id != arg->vdev_id) + return; + + ath12k_p2p_noa_update(arvif, arg->noa); +} + +void ath12k_p2p_noa_update_by_vdev_id(struct ath12k *ar, u32 vdev_id, + const struct ath12k_wmi_p2p_noa_info *noa) +{ + struct ath12k_p2p_noa_arg arg = { + .vdev_id = vdev_id, + .noa = noa, + }; + + ieee80211_iterate_active_interfaces_atomic(ath12k_ar_to_hw(ar), + IEEE80211_IFACE_ITER_NORMAL, + ath12k_p2p_noa_update_vdev_iter, + &arg); +} diff --git a/drivers/net/wireless/ath/ath12k/p2p.h b/drivers/net/wireless/ath/ath12k/p2p.h new file mode 100644 index 000000000000..b6f177fe4ff4 --- /dev/null +++ b/drivers/net/wireless/ath/ath12k/p2p.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: ISC */ +/* + * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.. + */ + +#ifndef ATH12K_P2P_H +#define ATH12K_P2P_H + +#include "wmi.h" + +struct ath12k_wmi_p2p_noa_info; + +struct ath12k_p2p_noa_arg { + u32 vdev_id; + const struct ath12k_wmi_p2p_noa_info *noa; +}; + +void ath12k_p2p_noa_update(struct ath12k_vif *arvif, + const struct ath12k_wmi_p2p_noa_info *noa); +void ath12k_p2p_noa_update_by_vdev_id(struct ath12k *ar, u32 vdev_id, + const struct ath12k_wmi_p2p_noa_info *noa); + +#endif diff --git a/drivers/net/wireless/ath/ath12k/wmi.c b/drivers/net/wireless/ath/ath12k/wmi.c index 98c27954f04f..cafe269f9f28 100644 --- a/drivers/net/wireless/ath/ath12k/wmi.c +++ b/drivers/net/wireless/ath/ath12k/wmi.c @@ -19,6 +19,7 @@ #include "mac.h" #include "hw.h" #include "peer.h" +#include "p2p.h" struct ath12k_wmi_svc_ready_parse { bool wmi_svc_bitmap_done; @@ -162,6 +163,10 @@ static const struct ath12k_wmi_tlv_policy ath12k_wmi_tlv_policies[] = { .min_len = sizeof(struct wmi_probe_resp_tx_status_event) }, [WMI_TAG_VDEV_DELETE_RESP_EVENT] = { .min_len = sizeof(struct wmi_vdev_delete_resp_event) }, + [WMI_TAG_P2P_NOA_INFO] = { + .min_len = sizeof(struct ath12k_wmi_p2p_noa_info) }, + [WMI_TAG_P2P_NOA_EVENT] = { + .min_len = sizeof(struct wmi_p2p_noa_event) }, }; static __le32 ath12k_wmi_tlv_hdr(u32 cmd, u32 len) @@ -1054,7 +1059,7 @@ int ath12k_wmi_vdev_start(struct ath12k *ar, struct wmi_vdev_start_req_arg *arg, tlv->header = ath12k_wmi_tlv_hdr(WMI_TAG_ARRAY_STRUCT, 0); /* Note: This is a nested TLV containing: - * [wmi_tlv][wmi_p2p_noa_descriptor][wmi_tlv].. + * [wmi_tlv][ath12k_wmi_p2p_noa_descriptor][wmi_tlv].. */ ptr += sizeof(*tlv); @@ -6672,6 +6677,47 @@ static void ath12k_probe_resp_tx_status_event(struct ath12k_base *ab, kfree(tb); } +static int ath12k_wmi_p2p_noa_event(struct ath12k_base *ab, + struct sk_buff *skb) +{ + const void **tb; + const struct wmi_p2p_noa_event *ev; + const struct ath12k_wmi_p2p_noa_info *noa; + struct ath12k *ar; + int ret, vdev_id; + + tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC); + if (IS_ERR(tb)) { + ret = PTR_ERR(tb); + ath12k_warn(ab, "failed to parse tlv: %d\n", ret); + return ret; + } + + ev = tb[WMI_TAG_P2P_NOA_EVENT]; + noa = tb[WMI_TAG_P2P_NOA_INFO]; + + if (!ev || !noa) { + kfree(tb); + return -EPROTO; + } + + vdev_id = __le32_to_cpu(ev->vdev_id); + + ath12k_dbg(ab, ATH12K_DBG_WMI, + "wmi tlv p2p noa vdev_id %i descriptors %u\n", + vdev_id, le32_get_bits(noa->noa_attr, WMI_P2P_NOA_INFO_DESC_NUM)); + ar = ath12k_mac_get_ar_by_vdev_id(ab, vdev_id); + if (!ar) { + ath12k_warn(ab, "invalid vdev id %d in P2P NoA event\n", + vdev_id); + return -EINVAL; + } + + ath12k_p2p_noa_update_by_vdev_id(ar, vdev_id, noa); + kfree(tb); + return 0; +} + static void ath12k_rfkill_state_change_event(struct ath12k_base *ab, struct sk_buff *skb) { @@ -6807,6 +6853,9 @@ static void ath12k_wmi_op_rx(struct ath12k_base *ab, struct sk_buff *skb) case WMI_RFKILL_STATE_CHANGE_EVENTID: ath12k_rfkill_state_change_event(ab, skb); break; + case WMI_P2P_NOA_EVENTID: + ath12k_wmi_p2p_noa_event(ab, skb); + break; /* add Unsupported events here */ case WMI_TBTTOFFSET_EXT_UPDATE_EVENTID: case WMI_PEER_OPER_MODE_CHANGE_EVENTID: diff --git a/drivers/net/wireless/ath/ath12k/wmi.h b/drivers/net/wireless/ath/ath12k/wmi.h index b017e36e1d85..6fb8c1a787a5 100644 --- a/drivers/net/wireless/ath/ath12k/wmi.h +++ b/drivers/net/wireless/ath/ath12k/wmi.h @@ -3492,6 +3492,37 @@ struct wmi_get_pdev_temperature_cmd { __le32 pdev_id; } __packed; +#define WMI_P2P_MAX_NOA_DESCRIPTORS 4 + +struct wmi_p2p_noa_event { + __le32 vdev_id; +} __packed; + +struct ath12k_wmi_p2p_noa_descriptor { + __le32 type_count; /* 255: continuous schedule, 0: reserved */ + __le32 duration; /* Absent period duration in micro seconds */ + __le32 interval; /* Absent period interval in micro seconds */ + __le32 start_time; /* 32 bit tsf time when in starts */ +} __packed; + +#define WMI_P2P_NOA_INFO_CHANGED_FLAG BIT(0) +#define WMI_P2P_NOA_INFO_INDEX GENMASK(15, 8) +#define WMI_P2P_NOA_INFO_OPP_PS BIT(16) +#define WMI_P2P_NOA_INFO_CTWIN_TU GENMASK(23, 17) +#define WMI_P2P_NOA_INFO_DESC_NUM GENMASK(31, 24) + +struct ath12k_wmi_p2p_noa_info { + /* Bit 0 - Flag to indicate an update in NOA schedule + * Bits 7-1 - Reserved + * Bits 15-8 - Index (identifies the instance of NOA sub element) + * Bit 16 - Opp PS state of the AP + * Bits 23-17 - Ctwindow in TUs + * Bits 31-24 - Number of NOA descriptors + */ + __le32 noa_attr; + struct ath12k_wmi_p2p_noa_descriptor descriptors[WMI_P2P_MAX_NOA_DESCRIPTORS]; +} __packed; + #define WMI_BEACON_TX_BUFFER_SIZE 512 struct wmi_bcn_tmpl_cmd {