Allow mhi_sync_power_up to handle SYS_ERR during power-up, reboot,
or recovery. This is to avoid premature exit when MHI_PM_IN_ERROR_STATE is
observed during above mentioned system states.
To achieve this, treat SYS_ERR as a valid state and let its handler process
the error and queue the next transition to Mission Mode instead of aborting
early.
Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
[mani: reworded description]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Link: https://patch.msgid.link/20250912-uevent_vdev_next-20250911-v4-5-fa2f6ccd301b@quicinc.com
So, When the MHI driver is removed from the host side, it is essential to
ensure a clean and stable recovery of the device. This commit introduces
the following steps to achieve that:
1. Disable SR-IOV for any SR-IOV-enabled devices on the Physical Function.
2. Perform a SOC_RESET on the PF to fully reset the device.
Disabling SR-IOV ensures all Virtual Functions (VFs) are properly shutdown,
preventing issues during the reset process. The SOC_RESET guarantees that
the PF is restored to a known good state.
If soc_reset is not performed device at driver remove, device will be
stuck in mission mode state and subsequent driver insert/power_up will not
proceed further.
Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
[mani: reworded subject]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Link: https://patch.msgid.link/20250912-uevent_vdev_next-20250911-v4-4-fa2f6ccd301b@quicinc.com
In SR-IOV enabled devices, reading the VF DEVICE/VENDOR ID register
returns `FFFFh`, as specified in section 3.4.1.1 of the PCIe SR-IOV spec.
To accurately determine device activity, read the PCIe VENDOR_ID of
the Physical Function (PF) instead.
Health check monitoring for Virtual Functions (VFs) has been disabled,
since VFs are not physical functions and lack direct hardware control.
This change prevents unnecessary CPU cycles from being consumed by VF
health checks, which are both unintended and non-functional.
Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Reviewed-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
Link: https://patch.msgid.link/20250912-uevent_vdev_next-20250911-v4-2-fa2f6ccd301b@quicinc.com
Implement support for separate controller configurations for both
Virtual Functions (VF) and Physical Functions (PF).
This enhancement allows for more flexible and efficient management of
resources. The PF takes on a supervisory role and will have bootup
information such as SAHARA, DIAG, and NDB (for file system sync data,
etc.). VFs can handle resources associated with the main data movement
of the Function are available to the SI (system image) as per PCIe SRIOV
spec (rev 0.9 1.Architectural overview)
Signed-off-by: Vivek Pernamitta <quic_vpernami@quicinc.com>
Reviewed-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Link: https://patch.msgid.link/20250912-uevent_vdev_next-20250911-v4-1-fa2f6ccd301b@quicinc.com
Currently only array maps are supported, but the implementation can be
extended for other maps and objects. The hash is memoized only for
exclusive and frozen maps as their content is stable until the exclusive
program modifies the map.
This is required for BPF signing, enabling a trusted loader program to
verify a map's integrity. The loader retrieves
the map's runtime hash from the kernel and compares it against an
expected hash computed at build time.
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250914215141.15144-7-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Use AF_ALG sockets to not have libbpf depend on OpenSSL. The helper is
used for the loader generation code to embed the metadata hash in the
loader program and also by the bpf_map__make_exclusive API to calculate
the hash of the program the map is exclusive to.
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250914215141.15144-4-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Exclusive maps allow maps to only be accessed by program with a
program with a matching hash which is specified in the excl_prog_hash
attr.
For the signing use-case, this allows the trusted loader program
to load the map and verify the integrity
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250914215141.15144-3-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Exclusive maps restrict map access to specific programs using a hash.
The current hash used for this is SHA1, which is prone to collisions.
This patch uses SHA256, which is more resilient against
collisions. This new hash is stored in bpf_prog and used by the verifier
to determine if a program can access a given exclusive map.
The original 64-bit tags are kept, as they are used by users as a short,
possibly colliding program identifier for non-security purposes.
Signed-off-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/20250914215141.15144-2-kpsingh@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a README file for RISC-V specific kernel selftests under
tools/testing/selftests/riscv/. This mirrors the existing README
for arm64, providing clear guidance on how the tests are architecture
specific and skipped on non-riscv systems. It also includes
standard make commands for building, running and installing the
tests, along with a reference to general kselftest documentation.
Signed-off-by: Bala-Vignesh-Reddy <reddybalavignesh9979@gmail.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20250815180724.14459-1-reddybalavignesh9979@gmail.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Current implementation stores the bus generation at which the bus manager
contending procedure finishes. The condition for the procedure is the
mismatch of the stored generation against current bus generation.
This commit refactors the code for the contending procedure. Two existing
branches are put into a new branch to detect the generation mismatch, thus
the most of change is indentation.
Link: https://lore.kernel.org/r/20250918235448.129705-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Two functions, fw_core_handle_bus_reset() and bm_work(), are serialized
by a commit 3d91fd440cc7 ("firewire: core: disable bus management work
temporarily during updating topology"). Therefore the generation member
of fw_card is immutable in bm_work().
This commit removes useless generation check in bm_work().
Link: https://lore.kernel.org/r/20250918235448.129705-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Currently, ath12k_mac_handle_beacon_miss() does not handle the beacon
miss for the MLO case.
In MLO scenarios, the host fails to process the beacon miss because the
vdev_id comparison in ath12k_mac_handle_beacon_miss_iter() does not match.
This mismatch occurs since arvif always points to ahvif->deflink, which may
not correspond to the actual vdev_id associated with the event.
Fix this by retrieving arvif from vdev_id instead of ahvif->deflink which
will work for both MLO and Non-MLO case.
Also refactor the ath12k_mac_handle_beacon_miss(), by passing arvif
directly instead of vdev_id and remove ath12k_mac_handle_beacon_miss_iter()
which is no longer needed.
ath12k_mac_handle_beacon_miss() is called from ath12k_roam_event() for WCN
chipsets and ath12k_peer_sta_kickout_event() for QCN chipsets.
So, refactor the ath12k_roam_event() to pass arvif instead vdev_id to the
ath12k_mac_handle_beacon_miss() function to align with the
ath12k_peer_sta_kickout_event() and change the rcu_read_lock() to
guard(rcu)() in the same function ath12k_roam_event().
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00284-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1
Co-developed-by: Aditya Kumar Singh <aditya.kumar.singh@oss.qualcomm.com>
Signed-off-by: Aditya Kumar Singh <aditya.kumar.singh@oss.qualcomm.com>
Signed-off-by: Maharaja Kennadyrajan <maharaja.kennadyrajan@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250812111708.3686-4-maharaja.kennadyrajan@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Currently, when the non-AP STA connected to the AP STA, and the AP STA goes
down or becomes inactive without indication, firmware detects the beacon
miss and sends the WMI event WMI_PEER_STA_KICKOUT_EVENTID with reason as
INACTIVITY. The host driver handles this event as low ACK and reports it to
the mac80211 driver.
However, the expectation is that non-AP STA should be disconnected from
AP STA instantly once it receives the STA kickout event with reason of
inactivity.
Trigger a disconnect from AP STA through beacon miss handling upon
receiving non-AP STA peer kickout event with reason code inactivity.
Replace the helper function ath12k_mac_get_ar_by_vdev_id() with
ath12k_mac_get_arvif_by_vdev_id() due to the following reasons.
1. Check the station VIF type for handling the beacon miss.
2. Retrieve the proper ar from the arvif by checking the vdev_id with
vdev_map and link_map lookup which is needed for the MLO case in the
following patch.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1
Co-developed-by: Ramya Gnanasekar <ramya.gnanasekar@oss.qualcomm.com>
Signed-off-by: Ramya Gnanasekar <ramya.gnanasekar@oss.qualcomm.com>
Signed-off-by: Arulanbu Balusamy <quic_abalusam@quicinc.com>
Co-developed-by: Maharaja Kennadyrajan <maharaja.kennadyrajan@oss.qualcomm.com>
Signed-off-by: Maharaja Kennadyrajan <maharaja.kennadyrajan@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250812111708.3686-3-maharaja.kennadyrajan@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Currently, command “iw wlan0 station dump” does not show per-chain signal
strength.
This is because ath12k does not handle the num_per_chain_rssi and
rssi_avg_beacon reported by firmware to ath12k.
To address this, update ath12k to send WMI_REQUEST_STATS_CMDID with the
flag WMI_REQUEST_RSSI_PER_CHAIN_STAT to the firmware. Then, add logic to
handle num_per_chain_rssi and rssi_avg_beacon in the
ath12k_wmi_tlv_fw_stats_parse(), and assign the resulting per-chain signal
strength to the chain_signal of struct station_info.
After that, "iw dev xxx station dump" shows the correct per-chain signal
strength.
Such as:
Station AA:BB:CC:DD:EE:FF (on wlan0)
inactive time: 212 ms
rx bytes: 10398
rx packets: 64
tx bytes: 4362
tx packets: 33
tx retries: 49
tx failed: 0
beacon loss: 0
beacon rx: 14
rx drop misc: 16
signal: -45 [-51, -46] dBm
beacon signal avg: -44 dBm
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0-03427-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.15378.4
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219751
Signed-off-by: Lingbo Kong <lingbo.kong@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250812030044.688-1-quic_lingbok@quicinc.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Use the newly added of_reserved_mem_region_to_resource() function to
handle "memory-region" properties.
The error handling is a bit different for ath10k. "memory-region" is
optional, so failed lookup is not an error. But then an error in
of_address_to_resource() is treated as an error. However, that
distinction is not really important. Either the region is available
and usable or it is not. So now, it is just
of_reserved_mem_region_to_resource() which is checked for an error.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250813214933.897486-1-robh@kernel.org
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
The leds-gpio traditionally takes a global gpio number in its platform
data, but the number assigned here is not actually such a number but
only meant to be used internally to this driver.
As part of the kernel-wide cleanup of the old gpiolib interfaces, the
'gpio' number field is going away, so to keep ath10k building, move
the assignment into a private structure instead.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Link: https://patch.msgid.link/20250808151822.536879-17-arnd@kernel.org
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
There are two rings involved in the Copy Engine (CE) receive path
handling, the CE status (STS) ring and the CE destination (DST) ring.
Each time CE hardware needs to send an event (e.g. WMI event) to host,
CE hardware finds a buffer (to which the tail pointer (TP) points) in
DST ring and fills it with payload, then hardware fills meta data in
STS ring and fires interrupt to host. Please note the TP of DST ring is
expected to be advanced by CE hardware before interrupting host. While
handling the interrupt, host finds that DST ring buffers are used hence
increases rx_buf_needed to record the number of buffers to be replenished.
Note before that, host compares TP and head pointer (HP) of DST ring to
see if there is available space. Normally rx_buf_needed simply equals
available space. But sometimes CE hardware doesn't (for whatever reason)
update TP timely, making the comparison fails, then enqueue is cancelled
and a warning is logged.
However even enqueue fails this time, rx_buf_needed still records the
numbers of needed buffers. Later when TP gets updated correctly, the
missing buffer will be eventually replenished. And there is no doubt on
the late update, it always comes (or lots of such warnings should be seen).
Since this won't cause any functional issue, downgrade logging level to
avoid misleading.
Compile tested only.
Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250815-ath-dont-warn-on-ce-enqueue-fail-v1-3-f955ddc3ba7a@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
There are two rings involved in the Copy Engine (CE) receive path
handling, the CE status (STS) ring and the CE destination (DST) ring.
Each time CE hardware needs to send an event (e.g. WMI event) to host,
CE hardware finds a buffer (to which the tail pointer (TP) points) in
DST ring and fills it with payload, then hardware fills meta data in
STS ring and fires interrupt to host. Please note the TP of DST ring is
expected to be advanced by CE hardware before interrupting host. While
handling the interrupt, host finds that DST ring buffers are used hence
increases rx_buf_needed to record the number of buffers to be replenished.
Note before that, host compares TP and head pointer (HP) of DST ring to
see if there is available space. Normally rx_buf_needed simply equals
available space. But sometimes CE hardware doesn't (for whatever reason)
update TP timely, making the comparison fails, then enqueue is cancelled
and a warning is logged:
ath11k_pci 0000:02:00.0: failed to enqueue rx buf: -28
However even enqueue fails this time, rx_buf_needed still records the
numbers of needed buffers. Later when TP gets updated correctly, the
missing buffer will be eventually replenished. And there is no doubt on
the late update, it always comes (or lots of such warnings should be seen).
Since this won't cause any functional issue, downgrade logging level to
avoid misleading.
Compile tested only.
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220269
Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250815-ath-dont-warn-on-ce-enqueue-fail-v1-1-f955ddc3ba7a@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Currently, ath12k_dp_rx_h_ppdu() determines the band and frequency
based on the channel number and center frequency from the RX descriptor's
PHY metadata. However, in rare cases, it is observed that frequency
retrieved from the metadata may be invalid or unexpected especially for
6 GHz frames.
This can result in a NULL sband, which prevents proper frequency assignment
in rx_status and potentially leading to incorrect RX packet classification.
To fix this potential issue, add a fallback mechanism that uses
ar->rx_channel to populate the band and frequency when the derived
sband is invalid or missing.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1
Fixes: d889913205 ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Signed-off-by: Sriram R <quic_srirrama@quicinc.com>
Co-developed-by: Vinith Kumar R <quic_vinithku@quicinc.com>
Signed-off-by: Vinith Kumar R <quic_vinithku@quicinc.com>
Signed-off-by: Aishwarya R <aishwarya.r@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250723190651.699828-1-aishwarya.r@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Currently, host fetches combined rssi from rssi_comb in struct
hal_rx_phyrx_rssi_legacy_info.
rssi_comb is 8th to 15th bits of the second to last variable.
rssi_comb_ppdu is the 0th to 7th of the last variable.
When bandwidth = 20MHz, rssi_comb = rssi_comb_ppdu. But when bandwidth >
20MHz, rssi_comb < rssi_comb_ppdu because rssi_comb only includes power
of primary 20 MHz while rssi_comb_ppdu includes power of active
RUs/subchannels. So should fetch combined rssi from rssi_comb_ppdu.
Also related macro definitions are too long, rename them.
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.1.4.1-00199-QCAHKSWPL_SILICONZ-1
Fixes: d889913205 ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Signed-off-by: Kang Yang <kang.yang@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250722095934.67-4-kang.yang@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Current monitor mode will parse TLV HAL_PHYRX_OTHER_RECEIVE_INFO with
struct hal_phyrx_common_user_info.
Obviously, they do not match. The original intention here was to parse
HAL_PHYRX_COMMON_USER_INFO. So fix it by correctly parsing
HAL_PHYRX_COMMON_USER_INFO instead.
Also add LTF parsing and report to radiotap along with GI.
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.1.4.1-00199-QCAHKSWPL_SILICONZ-1
Fixes: d939919a36 ("wifi: ath12k: Add HAL_PHYRX_OTHER_RECEIVE_INFO TLV parsing support")
Signed-off-by: Kang Yang <kang.yang@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250722095934.67-3-kang.yang@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
In ath12k_mac_parse_tx_pwr_env(), for the non-PSD case num_pwr_levels is
limited by ATH12K_NUM_PWR_LEVELS which is 16:
if (tpc_info->num_pwr_levels > ATH12K_NUM_PWR_LEVELS)
tpc_info->num_pwr_levels = ATH12K_NUM_PWR_LEVELS;
Then it is used to iterate entries in local_non_psd->power[] and
reg_non_psd->power[]:
for (i = 0; i < tpc_info->num_pwr_levels; i++) {
tpc_info->tpe[i] = min(local_non_psd->power[i],
reg_non_psd->power[i]) / 2;
Since the two array are of size 5, Smatch warns:
drivers/net/wireless/ath/ath12k/mac.c:9812
ath12k_mac_parse_tx_pwr_env() error: buffer overflow 'local_non_psd->power' 5 <= 15
drivers/net/wireless/ath/ath12k/mac.c:9812
ath12k_mac_parse_tx_pwr_env() error: buffer overflow 'reg_non_psd->power' 5 <= 15
This is a false positive as there is already implicit limitation:
tpc_info->num_pwr_levels = max(local_non_psd->count,
reg_non_psd->count);
meaning it won't exceed 5.
However, to make robot happy, add explicit limit there.
Also add the same to the PSD case, although no warning due to
ATH12K_NUM_PWR_LEVELS equals IEEE80211_TPE_PSD_ENTRIES_320MHZ.
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00284-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1
Fixes: cccbb9d0dd ("wifi: ath12k: add parse of transmit power envelope element")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202505180703.Kr9OfQRP-lkp@intel.com/
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20250804-ath12k-fix-smatch-warning-on-6g-vlp-v1-2-56f1e54152ab@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Vivek Pernamitta
J. Neuschäfer
Dave Airlie
Liu Ying
Aleksa Paunovic
KP Singh
Clément Léger
Yunhui Cui
Bala-Vignesh-Reddy
Takashi Sakamoto
Andrew Davis
Maharaja Kennadyrajan
Arulanbu Balusamy
Lingbo Kong
Loic Poulain
Baochen Qiang
Matvey Kovalev
Rob Herring (Arm)
Arnd Bergmann
Liao Yuanhong
Sriram R
Kang Yang
Baochen Qiang