[v3] wcn36xx: Implement tx_rate reporting

Currently, the driver reports a tx_rate of 6.0 MBit/s no matter the true
rate:

root@linaro-developer:~# iw wlan0 link
Connected to 6c:f3:7f:eb:9b:92 (on wlan0)
        SSID: SQ-DEVICETEST
        freq: 5200
        RX: 4141 bytes (32 packets)
        TX: 2082 bytes (15 packets)
        signal: -77 dBm
        rx bitrate: 135.0 MBit/s MCS 6 40MHz short GI
        tx bitrate: 6.0 MBit/s

        bss flags:      short-slot-time
        dtim period:    1
        beacon int:     100

This patch requests HAL_GLOBAL_CLASS_A_STATS_INFO via a hal_get_stats
firmware message and reports it via ieee80211_ops::sta_statistics.

root@linaro-developer:~# iw wlan0 link
Connected to 6c:f3:7f:eb:73:b2 (on wlan0)
        SSID: SQ-DEVICETEST
        freq: 5700
        RX: 26788094 bytes (19859 packets)
        TX: 1101376 bytes (12119 packets)
        signal: -75 dBm
        rx bitrate: 135.0 MBit/s MCS 6 40MHz short GI
        tx bitrate: 108.0 MBit/s VHT-MCS 5 40MHz VHT-NSS 1

        bss flags:      short-slot-time
        dtim period:    1
        beacon int:     100

Tested on MSM8939 with WCN3680B running firmware CNSS-PR-2-0-1-2-c1-00083,
and verified by sniffing frames over the air with Wireshark to ensure the
MCS indices match.

Signed-off-by: Edmond Gagnon <egagnon@squareup.com>
Reviewed-by: Benjamin Li <benl@squareup.com>
---

Changes in v3:
 - Refactored to report tx_rate via ieee80211_ops::sta_statistics
 - Dropped get_sta_index patch
 - Addressed style comments
Changes in v2:
 - Refactored to use existing wcn36xx_hal_get_stats_{req,rsp}_msg structs.
 - Added more notes about testing.
 - Reduced reporting interval to 3000msec.
 - Assorted type and memory safety fixes.
 - Make wcn36xx_smd_get_stats friendlier to future message implementors.

 drivers/net/wireless/ath/wcn36xx/hal.h  |  7 +++-
 drivers/net/wireless/ath/wcn36xx/main.c | 16 +++++++
 drivers/net/wireless/ath/wcn36xx/smd.c  | 56 +++++++++++++++++++++++++
 drivers/net/wireless/ath/wcn36xx/smd.h  |  2 +
 drivers/net/wireless/ath/wcn36xx/txrx.c | 29 +++++++++++++
 drivers/net/wireless/ath/wcn36xx/txrx.h |  1 +
 6 files changed, 110 insertions(+), 1 deletion(-)

Tested on DB410c (WCN3620, 802.11n/2.4GHz only) running firmware
CNSS-PR-2-0-1-2-c1-74-130449-3, also with 5.17.

root@linaro-developer:~# speedtest
Retrieving speedtest.net configuration...
Testing from Square (135.84.132.205)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Open5G Inc. (Atherton, CA) [40.28 km]: 11.828 ms
Testing download speed................................................................................
Download: 3.00 Mbit/s
Testing upload speed......................................................................................................
Upload: 23.69 Mbit/s
root@linaro-developer:~#
root@linaro-developer:~# iw wlan0 link
Connected to 6c:f3:7f:eb:98:21 (on wlan0)
	SSID: SQ-DEVICETEST
	freq: 2412
	RX: 34119054 bytes (37804 packets)
	TX: 32924504 bytes (35073 packets)
	signal: -59 dBm
	rx bitrate: 57.8 MBit/s MCS 5 short GI
	tx bitrate: 58.5 MBit/s MCS 6

	bss flags:	short-preamble short-slot-time
	dtim period:	1
	beacon int:	100

Tested-by: Benjamin Li <benl@squareup.com>

Ben

On 3/23/22 2:45 PM, Edmond Gagnon wrote:
> Currently, the driver reports a tx_rate of 6.0 MBit/s no matter the true
> rate:
> 
> root@linaro-developer:~# iw wlan0 link
> Connected to 6c:f3:7f:eb:9b:92 (on wlan0)
>         SSID: SQ-DEVICETEST
>         freq: 5200
>         RX: 4141 bytes (32 packets)
>         TX: 2082 bytes (15 packets)
>         signal: -77 dBm
>         rx bitrate: 135.0 MBit/s MCS 6 40MHz short GI
>         tx bitrate: 6.0 MBit/s
> 
>         bss flags:      short-slot-time
>         dtim period:    1
>         beacon int:     100
> 
> This patch requests HAL_GLOBAL_CLASS_A_STATS_INFO via a hal_get_stats
> firmware message and reports it via ieee80211_ops::sta_statistics.
> 
> root@linaro-developer:~# iw wlan0 link
> Connected to 6c:f3:7f:eb:73:b2 (on wlan0)
>         SSID: SQ-DEVICETEST
>         freq: 5700
>         RX: 26788094 bytes (19859 packets)
>         TX: 1101376 bytes (12119 packets)
>         signal: -75 dBm
>         rx bitrate: 135.0 MBit/s MCS 6 40MHz short GI
>         tx bitrate: 108.0 MBit/s VHT-MCS 5 40MHz VHT-NSS 1
> 
>         bss flags:      short-slot-time
>         dtim period:    1
>         beacon int:     100
> 
> Tested on MSM8939 with WCN3680B running firmware CNSS-PR-2-0-1-2-c1-00083,
> and verified by sniffing frames over the air with Wireshark to ensure the
> MCS indices match.
> 
> Signed-off-by: Edmond Gagnon <egagnon@squareup.com>
> Reviewed-by: Benjamin Li <benl@squareup.com>
> ---
> 
> Changes in v3:
>  - Refactored to report tx_rate via ieee80211_ops::sta_statistics
>  - Dropped get_sta_index patch
>  - Addressed style comments
> Changes in v2:
>  - Refactored to use existing wcn36xx_hal_get_stats_{req,rsp}_msg structs.
>  - Added more notes about testing.
>  - Reduced reporting interval to 3000msec.
>  - Assorted type and memory safety fixes.
>  - Make wcn36xx_smd_get_stats friendlier to future message implementors.
> 
>  drivers/net/wireless/ath/wcn36xx/hal.h  |  7 +++-
>  drivers/net/wireless/ath/wcn36xx/main.c | 16 +++++++
>  drivers/net/wireless/ath/wcn36xx/smd.c  | 56 +++++++++++++++++++++++++
>  drivers/net/wireless/ath/wcn36xx/smd.h  |  2 +
>  drivers/net/wireless/ath/wcn36xx/txrx.c | 29 +++++++++++++
>  drivers/net/wireless/ath/wcn36xx/txrx.h |  1 +
>  6 files changed, 110 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/ath/wcn36xx/hal.h b/drivers/net/wireless/ath/wcn36xx/hal.h
> index 2a1db9756fd5..46a49f0a51b3 100644
> --- a/drivers/net/wireless/ath/wcn36xx/hal.h
> +++ b/drivers/net/wireless/ath/wcn36xx/hal.h
> @@ -2626,7 +2626,12 @@ enum tx_rate_info {
>  	HAL_TX_RATE_SGI = 0x8,
>  
>  	/* Rate with Long guard interval */
> -	HAL_TX_RATE_LGI = 0x10
> +	HAL_TX_RATE_LGI = 0x10,
> +
> +	/* VHT rates */
> +	HAL_TX_RATE_VHT20  = 0x20,
> +	HAL_TX_RATE_VHT40  = 0x40,
> +	HAL_TX_RATE_VHT80  = 0x80,
>  };
>  
>  struct ani_global_class_a_stats_info {
> diff --git a/drivers/net/wireless/ath/wcn36xx/main.c b/drivers/net/wireless/ath/wcn36xx/main.c
> index b545d4b2b8c4..fc76b090c39f 100644
> --- a/drivers/net/wireless/ath/wcn36xx/main.c
> +++ b/drivers/net/wireless/ath/wcn36xx/main.c
> @@ -1400,6 +1400,21 @@ static int wcn36xx_get_survey(struct ieee80211_hw *hw, int idx,
>  	return 0;
>  }
>  
> +static void wcn36xx_sta_statistics(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
> +				   struct ieee80211_sta *sta, struct station_info *sinfo)
> +{
> +	struct wcn36xx *wcn;
> +	u8 sta_index;
> +	int status = 0;
> +
> +	wcn = hw->priv;
> +	sta_index = get_sta_index(vif, wcn36xx_sta_to_priv(sta));
> +	status = wcn36xx_smd_get_stats(wcn, sta_index, HAL_GLOBAL_CLASS_A_STATS_INFO, sinfo);
> +
> +	if (status)
> +		wcn36xx_err("wcn36xx_smd_get_stats failed\n");
> +}
> +
>  static const struct ieee80211_ops wcn36xx_ops = {
>  	.start			= wcn36xx_start,
>  	.stop			= wcn36xx_stop,
> @@ -1423,6 +1438,7 @@ static const struct ieee80211_ops wcn36xx_ops = {
>  	.set_rts_threshold	= wcn36xx_set_rts_threshold,
>  	.sta_add		= wcn36xx_sta_add,
>  	.sta_remove		= wcn36xx_sta_remove,
> +	.sta_statistics		= wcn36xx_sta_statistics,
>  	.ampdu_action		= wcn36xx_ampdu_action,
>  #if IS_ENABLED(CONFIG_IPV6)
>  	.ipv6_addr_change	= wcn36xx_ipv6_addr_change,
> diff --git a/drivers/net/wireless/ath/wcn36xx/smd.c b/drivers/net/wireless/ath/wcn36xx/smd.c
> index caeb68901326..8f9aa892e5ec 100644
> --- a/drivers/net/wireless/ath/wcn36xx/smd.c
> +++ b/drivers/net/wireless/ath/wcn36xx/smd.c
> @@ -2627,6 +2627,61 @@ int wcn36xx_smd_del_ba(struct wcn36xx *wcn, u16 tid, u8 direction, u8 sta_index)
>  	return ret;
>  }
>  
> +int wcn36xx_smd_get_stats(struct wcn36xx *wcn, u8 sta_index, u32 stats_mask,
> +			  struct station_info *sinfo)
> +{
> +	struct wcn36xx_hal_stats_req_msg msg_body;
> +	struct wcn36xx_hal_stats_rsp_msg *rsp;
> +	void *rsp_body;
> +	int ret = 0;
> +
> +	if (stats_mask & ~HAL_GLOBAL_CLASS_A_STATS_INFO) {
> +		wcn36xx_err("stats_mask 0x%x contains unimplemented types\n",
> +			    stats_mask);
> +		return -EINVAL;
> +	}
> +
> +	mutex_lock(&wcn->hal_mutex);
> +	INIT_HAL_MSG(msg_body, WCN36XX_HAL_GET_STATS_REQ);
> +
> +	msg_body.sta_id = sta_index;
> +	msg_body.stats_mask = stats_mask;
> +
> +	PREPARE_HAL_BUF(wcn->hal_buf, msg_body);
> +
> +	ret = wcn36xx_smd_send_and_wait(wcn, msg_body.header.len);
> +	if (ret) {
> +		wcn36xx_err("sending hal_get_stats failed\n");
> +		goto out;
> +	}
> +
> +	ret = wcn36xx_smd_rsp_status_check(wcn->hal_buf, wcn->hal_rsp_len);
> +	if (ret) {
> +		wcn36xx_err("hal_get_stats response failed err=%d\n", ret);
> +		goto out;
> +	}
> +
> +	rsp = (struct wcn36xx_hal_stats_rsp_msg *)wcn->hal_buf;
> +	rsp_body = (wcn->hal_buf + sizeof(struct wcn36xx_hal_stats_rsp_msg));
> +
> +	if (rsp->stats_mask != stats_mask) {
> +		wcn36xx_err("stats_mask 0x%x differs from requested 0x%x\n",
> +			    rsp->stats_mask, stats_mask);
> +		goto out;
> +	}
> +
> +	if (rsp->stats_mask & HAL_GLOBAL_CLASS_A_STATS_INFO) {
> +		wcn36xx_process_tx_rate((struct ani_global_class_a_stats_info *)rsp_body,
> +					&sinfo->txrate);
> +		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BITRATE);
> +		rsp_body += sizeof(struct ani_global_class_a_stats_info);
> +	}
> +out:
> +	mutex_unlock(&wcn->hal_mutex);
> +
> +	return ret;
> +}
> +
>  static int wcn36xx_smd_trigger_ba_rsp(void *buf, int len, struct add_ba_info *ba_info)
>  {
>  	struct wcn36xx_hal_trigger_ba_rsp_candidate *candidate;
> @@ -3316,6 +3371,7 @@ int wcn36xx_smd_rsp_process(struct rpmsg_device *rpdev,
>  	case WCN36XX_HAL_ADD_BA_SESSION_RSP:
>  	case WCN36XX_HAL_ADD_BA_RSP:
>  	case WCN36XX_HAL_DEL_BA_RSP:
> +	case WCN36XX_HAL_GET_STATS_RSP:
>  	case WCN36XX_HAL_TRIGGER_BA_RSP:
>  	case WCN36XX_HAL_UPDATE_CFG_RSP:
>  	case WCN36XX_HAL_JOIN_RSP:
> diff --git a/drivers/net/wireless/ath/wcn36xx/smd.h b/drivers/net/wireless/ath/wcn36xx/smd.h
> index 957cfa87fbde..3fd598ac2a27 100644
> --- a/drivers/net/wireless/ath/wcn36xx/smd.h
> +++ b/drivers/net/wireless/ath/wcn36xx/smd.h
> @@ -138,6 +138,8 @@ int wcn36xx_smd_add_ba_session(struct wcn36xx *wcn,
>  int wcn36xx_smd_add_ba(struct wcn36xx *wcn, u8 session_id);
>  int wcn36xx_smd_del_ba(struct wcn36xx *wcn, u16 tid, u8 direction, u8 sta_index);
>  int wcn36xx_smd_trigger_ba(struct wcn36xx *wcn, u8 sta_index, u16 tid, u16 *ssn);
> +int wcn36xx_smd_get_stats(struct wcn36xx *wcn, u8 sta_index, u32 stats_mask,
> +			  struct station_info *sinfo);
>  
>  int wcn36xx_smd_update_cfg(struct wcn36xx *wcn, u32 cfg_id, u32 value);
>  
> diff --git a/drivers/net/wireless/ath/wcn36xx/txrx.c b/drivers/net/wireless/ath/wcn36xx/txrx.c
> index df749b114568..8da3955995b6 100644
> --- a/drivers/net/wireless/ath/wcn36xx/txrx.c
> +++ b/drivers/net/wireless/ath/wcn36xx/txrx.c
> @@ -699,3 +699,32 @@ int wcn36xx_start_tx(struct wcn36xx *wcn,
>  
>  	return ret;
>  }
> +
> +void wcn36xx_process_tx_rate(struct ani_global_class_a_stats_info *stats, struct rate_info *info)
> +{
> +	/* tx_rate is in units of 500kbps; mac80211 wants them in 100kbps */
> +	if (stats->tx_rate_flags & HAL_TX_RATE_LEGACY)
> +		info->legacy = stats->tx_rate * 5;
> +
> +	info->flags = 0;
> +	info->mcs = stats->mcs_index;
> +	info->nss = 1;
> +
> +	if (stats->tx_rate_flags & (HAL_TX_RATE_HT20 | HAL_TX_RATE_HT40))
> +		info->flags |= RATE_INFO_FLAGS_MCS;
> +
> +	if (stats->tx_rate_flags & (HAL_TX_RATE_VHT20 | HAL_TX_RATE_VHT40 | HAL_TX_RATE_VHT80))
> +		info->flags |= RATE_INFO_FLAGS_VHT_MCS;
> +
> +	if (stats->tx_rate_flags & HAL_TX_RATE_SGI)
> +		info->flags |= RATE_INFO_FLAGS_SHORT_GI;
> +
> +	if (stats->tx_rate_flags & (HAL_TX_RATE_HT20 | HAL_TX_RATE_VHT20))
> +		info->bw = RATE_INFO_BW_20;
> +
> +	if (stats->tx_rate_flags & (HAL_TX_RATE_HT40 | HAL_TX_RATE_VHT40))
> +		info->bw = RATE_INFO_BW_40;
> +
> +	if (stats->tx_rate_flags & HAL_TX_RATE_VHT80)
> +		info->bw = RATE_INFO_BW_80;
> +}
> diff --git a/drivers/net/wireless/ath/wcn36xx/txrx.h b/drivers/net/wireless/ath/wcn36xx/txrx.h
> index b54311ffde9c..fb0d6cabd52b 100644
> --- a/drivers/net/wireless/ath/wcn36xx/txrx.h
> +++ b/drivers/net/wireless/ath/wcn36xx/txrx.h
> @@ -164,5 +164,6 @@ int  wcn36xx_rx_skb(struct wcn36xx *wcn, struct sk_buff *skb);
>  int wcn36xx_start_tx(struct wcn36xx *wcn,
>  		     struct wcn36xx_sta *sta_priv,
>  		     struct sk_buff *skb);
> +void wcn36xx_process_tx_rate(struct ani_global_class_a_stats_info *stats, struct rate_info *info);
>  
>  #endif	/* _TXRX_H_ */