FROMGIT: wifi: ath11k: Register relayfs entries for CFR dump

Provide a relayfs interface to collect the CFR dump from the user space.

'/sys/kernel/debug/ieee80211/phyX/ath11k/cfr_capture' is exposed to user
space to get CFR data.

CFR format to user space:
 ___________________________________________
| CFR header | CFR payload | CFR tail data |
|____________|_____________|_______________|

CFR header contains the following fields,

* Start magic number 0xDEADBEAF - 4 bytes
* vendor id - 4 bytes
* cfr metadata version - 1 byte
* cfr data version - 1 byte
* device type - 1 byte
* platform type - 1 byte
* CFR metadata length - 4 bytes
* metadata - 92 bytes
        peer mac - 6 bytes
        capture status - 1 byte (1 for success 0 for failure)
        capture_bw - 1 byte
        channel_bw - 1 byte
        phy_mode - 1 byte
        prim20_chan - 2 bytes
        center_freq1 - 2 bytes
        center_freq2 - 2 bytes
        capture_mode - 1 byte
        capture_type - 1 byte
        sts_count - 1 byte
        num_rx_chain - 1 byte
        timestamp - 4 bytes
        length - 4 bytes
        chain_rssi - 32 bytes (4 bytes for each chain)
        chain_phase - 16 bytes (2 bytes for each chain)
        cfo_measurement - 4 bytes
        agc_gain - 8 bytes (1 bytes for each chain)
        rx_start_ts - 4 bytes

CFR payload:

CFR payload contains 8bytes of ucode header followed by the tone
information. Tone order is positive tones, followed by PHY memory
garbage, followed by negative tones. Dummy tones are uploaded to make
number of tones always integer number of 64. Number of tones is not
preamble type dependent.

Each CFR tone has 14-bit I component and 14-bit Q component and is sign
extended to 16-bit I/Q. Two tones are packed into one 64-bit unit as:

[63:0] = [Tone1_Q(63:48) Tone1_I(47:32) Tone0_Q(31:16) Tone0_I(15:0)]

CFR tail: end magic number 0xBEAFDEAD

Tested-on: IPQ8074 hw2.0 PCI IPQ8074 WLAN.HK.2.5.0.1-00991-QCAHKSWPL_SILICONZ-1
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04685-QCAHSPSWPL_V1_V2_SILICONZ_IOE-1

Signed-off-by: Venkateswara Naralasetty <quic_vnaralas@quicinc.com>
Co-developed-by: Yu Zhang (Yuriy) <yu.zhang@oss.qualcomm.com>
Signed-off-by: Yu Zhang (Yuriy) <yu.zhang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Signed-off-by: Qian Zhang <qian.zhang@oss.qualcomm.com>
Link: https://patch.msgid.link/20251230082520.3401007-3-qian.zhang@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>

Author: Venkateswara Naralasetty

drivers/net/wireless/ath/ath11k/cfr.c

@@ -416,10 +416,45 @@ static void ath11k_cfr_debug_unregister(struct ath11k *ar)
 	ar->cfr.enable_cfr = NULL;
 	debugfs_remove(ar->cfr.cfr_unassoc);
 	ar->cfr.cfr_unassoc = NULL;
+
+	relay_close(ar->cfr.rfs_cfr_capture);
+	ar->cfr.rfs_cfr_capture = NULL;
 }
 
+static struct dentry *ath11k_cfr_create_buf_file_handler(const char *filename,
+							 struct dentry *parent,
+							 umode_t mode,
+							 struct rchan_buf *buf,
+							 int *is_global)
+{
+	struct dentry *buf_file;
+
+	buf_file = debugfs_create_file(filename, mode, parent, buf,
+				       &relay_file_operations);
+	*is_global = 1;
+	return buf_file;
+}
+
+static int ath11k_cfr_remove_buf_file_handler(struct dentry *dentry)
+{
+	debugfs_remove(dentry);
+
+	return 0;
+}
+
+static const struct rchan_callbacks rfs_cfr_capture_cb = {
+	.create_buf_file = ath11k_cfr_create_buf_file_handler,
+	.remove_buf_file = ath11k_cfr_remove_buf_file_handler,
+};
+
 static void ath11k_cfr_debug_register(struct ath11k *ar)
 {
+	ar->cfr.rfs_cfr_capture = relay_open("cfr_capture",
+					     ar->debug.debugfs_pdev,
+					     ar->ab->hw_params.cfr_stream_buf_size,
+					     ar->ab->hw_params.cfr_num_stream_bufs,
+					     &rfs_cfr_capture_cb, NULL);
+
 	ar->cfr.enable_cfr = debugfs_create_file("enable_cfr", 0600,
 						 ar->debug.debugfs_pdev, ar,
 						 &fops_enable_cfr);

drivers/net/wireless/ath/ath11k/cfr.h

@@ -60,6 +60,7 @@ struct ath11k_cfr {
 	struct ath11k_look_up_table *lut;
 	struct dentry *enable_cfr;
 	struct dentry *cfr_unassoc;
+	struct rchan *rfs_cfr_capture;
 	u8 cfr_enabled_peer_cnt;
 	u32 lut_num;
 	u64 tx_evt_cnt;