Fix WFA certification failures due to flow control credit issues.
Also fix an issue with a varialbe (dwell time) that is not properly
initialized.
Amar Shankar (1):
brcmfmac: reserve 2 credits for host tx control path
Chung-Hsien Hsu (1):
brcmfmac: update tx status flags to sync with firmware
Double Lo (1):
brcmfmac: fix throughput zero stalls on PM 1 mode due to credit map
Jia-Shyr Chuang (1):
brcmfmac: increase message buffer size for control packets
Joseph Chuang (1):
brcmfmac: initialize the requested dwell time
Raveendran Somu (1):
brcmfmac: allow credit borrowing for all access categories
.../broadcom/brcm80211/brcmfmac/cfg80211.c | 2 +-
.../broadcom/brcm80211/brcmfmac/fwsignal.c | 68 +++++++++++++------
.../broadcom/brcm80211/brcmfmac/msgbuf.c | 3 +-
.../broadcom/brcm80211/brcmfmac/p2p.c | 5 +-
.../broadcom/brcm80211/brcmfmac/sdio.c | 15 +++-
5 files changed, 65 insertions(+), 28 deletions(-)
--
2.25.0
From: Raveendran Somu <[email protected]>
Current credit borrowing allows only the access category BE to
borrow the credits. This change is to fix the credit borrowing
logic, to make borrowing available for all access categories
and also to borrow only from the lower categories. This fixes WFA
802.11n certs 5.2.27 failures.
Signed-off-by: Raveendran Somu <[email protected]>
Signed-off-by: Jia-Shyr Chuang <[email protected]>
Signed-off-by: Chung-Hsien Hsu <[email protected]>
Signed-off-by: Chi-hsien Lin <[email protected]>
---
.../broadcom/brcm80211/brcmfmac/fwsignal.c | 61 +++++++++++--------
1 file changed, 37 insertions(+), 24 deletions(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
index 09701262330d..d7c36af4b566 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
@@ -383,6 +383,7 @@ struct brcmf_fws_mac_descriptor {
};
#define BRCMF_FWS_HANGER_MAXITEMS 3072
+#define BRCMF_BORROW_RATIO 3
/**
* enum brcmf_fws_hanger_item_state - state of hanger item.
@@ -479,7 +480,8 @@ struct brcmf_fws_info {
u32 fifo_enqpkt[BRCMF_FWS_FIFO_COUNT];
int fifo_credit[BRCMF_FWS_FIFO_COUNT];
int init_fifo_credit[BRCMF_FWS_FIFO_COUNT];
- int credits_borrowed[BRCMF_FWS_FIFO_AC_VO + 1];
+ int credits_borrowed[BRCMF_FWS_FIFO_AC_VO + 1]
+ [BRCMF_FWS_FIFO_AC_VO + 1];
int deq_node_pos[BRCMF_FWS_FIFO_COUNT];
u32 fifo_credit_map;
u32 fifo_delay_map;
@@ -1185,13 +1187,11 @@ static void brcmf_fws_return_credits(struct brcmf_fws_info *fws,
if (!credits)
return;
- fws->fifo_credit_map |= 1 << fifo;
-
- if ((fifo == BRCMF_FWS_FIFO_AC_BE) &&
- (fws->credits_borrowed[0])) {
+ if (fifo > BRCMF_FWS_FIFO_AC_BK &&
+ fifo <= BRCMF_FWS_FIFO_AC_VO) {
for (lender_ac = BRCMF_FWS_FIFO_AC_VO; lender_ac >= 0;
lender_ac--) {
- borrowed = &fws->credits_borrowed[lender_ac];
+ borrowed = &fws->credits_borrowed[fifo][lender_ac];
if (*borrowed) {
fws->fifo_credit_map |= (1 << lender_ac);
fifo_credit = &fws->fifo_credit[lender_ac];
@@ -1208,7 +1208,11 @@ static void brcmf_fws_return_credits(struct brcmf_fws_info *fws,
}
}
- fws->fifo_credit[fifo] += credits;
+ if (credits) {
+ fws->fifo_credit[fifo] += credits;
+ fws->fifo_credit_map |= 1 << fifo;
+ }
+
if (fws->fifo_credit[fifo] > fws->init_fifo_credit[fifo])
fws->fifo_credit[fifo] = fws->init_fifo_credit[fifo];
@@ -2005,27 +2009,31 @@ static void brcmf_fws_rollback_toq(struct brcmf_fws_info *fws,
}
}
-static int brcmf_fws_borrow_credit(struct brcmf_fws_info *fws)
+static int brcmf_fws_borrow_credit(struct brcmf_fws_info *fws,
+ int highest_lender_ac, int borrower_ac,
+ bool borrow_all)
{
- int lender_ac;
+ int lender_ac, borrow_limit = 0;
- if (time_after(fws->borrow_defer_timestamp, jiffies)) {
- fws->fifo_credit_map &= ~(1 << BRCMF_FWS_FIFO_AC_BE);
- return -ENAVAIL;
- }
+ for (lender_ac = 0; lender_ac <= highest_lender_ac; lender_ac++) {
- for (lender_ac = 0; lender_ac <= BRCMF_FWS_FIFO_AC_VO; lender_ac++) {
- if (fws->fifo_credit[lender_ac] > 0) {
- fws->credits_borrowed[lender_ac]++;
+ if (!borrow_all)
+ borrow_limit =
+ fws->init_fifo_credit[lender_ac] / BRCMF_BORROW_RATIO;
+ else
+ borrow_limit = 0;
+
+ if (fws->fifo_credit[lender_ac] > borrow_limit) {
+ fws->credits_borrowed[borrower_ac][lender_ac]++;
fws->fifo_credit[lender_ac]--;
if (fws->fifo_credit[lender_ac] == 0)
fws->fifo_credit_map &= ~(1 << lender_ac);
- fws->fifo_credit_map |= (1 << BRCMF_FWS_FIFO_AC_BE);
+ fws->fifo_credit_map |= (1 << borrower_ac);
brcmf_dbg(DATA, "borrow credit from: %d\n", lender_ac);
return 0;
}
}
- fws->fifo_credit_map &= ~(1 << BRCMF_FWS_FIFO_AC_BE);
+ fws->fifo_credit_map &= ~(1 << borrower_ac);
return -ENAVAIL;
}
@@ -2216,9 +2224,10 @@ static void brcmf_fws_dequeue_worker(struct work_struct *worker)
}
continue;
}
- while ((fws->fifo_credit[fifo] > 0) ||
+
+ while ((fws->fifo_credit[fifo]) ||
((!fws->bcmc_credit_check) &&
- (fifo == BRCMF_FWS_FIFO_BCMC))) {
+ (fifo == BRCMF_FWS_FIFO_BCMC))) {
skb = brcmf_fws_deq(fws, fifo);
if (!skb)
break;
@@ -2228,10 +2237,14 @@ static void brcmf_fws_dequeue_worker(struct work_struct *worker)
if (fws->bus_flow_blocked)
break;
}
- if ((fifo == BRCMF_FWS_FIFO_AC_BE) &&
- (fws->fifo_credit[fifo] <= 0) &&
- (!fws->bus_flow_blocked)) {
- while (brcmf_fws_borrow_credit(fws) == 0) {
+
+ if (fifo >= BRCMF_FWS_FIFO_AC_BE &&
+ fifo <= BRCMF_FWS_FIFO_AC_VO &&
+ fws->fifo_credit[fifo] == 0 &&
+ !fws->bus_flow_blocked) {
+ while (brcmf_fws_borrow_credit(fws,
+ fifo - 1, fifo,
+ true) == 0) {
skb = brcmf_fws_deq(fws, fifo);
if (!skb) {
brcmf_fws_return_credits(fws, fifo, 1);
--
2.25.0
From: Amar Shankar <[email protected]>
It is observed that sometimes when sdiod is low in tx credits in low
rssi scenarios, the data path consumes all sdiod rx all credits and
there is no sdiod rx credit available for control path causing host
and card to go out of sync resulting in link loss between host and
card. So in order to prevent it some credits are reserved for control
path.
Note that TXCTL_CREDITS can't be larger than the firmware default
credit update threshold 2; otherwise there will be a deadlock for both
side waiting for each other.
Signed-off-by: Amar Shankar <[email protected]>
Signed-off-by: Jia-Shyr Chuang <[email protected]>
Signed-off-by: Chi-Hsien Lin <[email protected]>
---
.../wireless/broadcom/brcm80211/brcmfmac/sdio.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
index ce6f15284277..163bb7f41e44 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
@@ -635,6 +635,8 @@ static const struct brcmf_firmware_mapping brcmf_sdio_fwnames[] = {
BRCMF_FW_ENTRY(CY_CC_43012_CHIP_ID, 0xFFFFFFFF, 43012)
};
+#define TXCTL_CREDITS 2
+
static void pkt_align(struct sk_buff *p, int len, int align)
{
uint datalign;
@@ -647,6 +649,14 @@ static void pkt_align(struct sk_buff *p, int len, int align)
/* To check if there's window offered */
static bool data_ok(struct brcmf_sdio *bus)
+{
+ /* Reserve TXCTL_CREDITS credits for txctl */
+ return (u8)(bus->tx_max - bus->tx_seq) > TXCTL_CREDITS &&
+ ((u8)(bus->tx_max - bus->tx_seq) & 0x80) == 0;
+}
+
+/* To check if there's window offered */
+static bool txctl_ok(struct brcmf_sdio *bus)
{
return (u8)(bus->tx_max - bus->tx_seq) != 0 &&
((u8)(bus->tx_max - bus->tx_seq) & 0x80) == 0;
@@ -2655,7 +2665,7 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
brcmf_sdio_clrintr(bus);
if (bus->ctrl_frame_stat && (bus->clkstate == CLK_AVAIL) &&
- data_ok(bus)) {
+ txctl_ok(bus)) {
sdio_claim_host(bus->sdiodev->func1);
if (bus->ctrl_frame_stat) {
err = brcmf_sdio_tx_ctrlframe(bus, bus->ctrl_frame_buf,
@@ -2663,6 +2673,9 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
bus->ctrl_frame_err = err;
wmb();
bus->ctrl_frame_stat = false;
+ if (err)
+ brcmf_err("sdio ctrlframe tx failed err=%d\n",
+ err);
}
sdio_release_host(bus->sdiodev->func1);
brcmf_sdio_wait_event_wakeup(bus);
--
2.25.0
From: Chung-Hsien Hsu <[email protected]>
There is a mismatch of tx status flag values between host and firmware.
It makes the host mistake the flags and have incorrect behavior of credit
returns. So update the flags to sync with the firmware ones.
Signed-off-by: Chung-Hsien Hsu <[email protected]>
Signed-off-by: Chi-hsien Lin <[email protected]>
---
.../wireless/broadcom/brcm80211/brcmfmac/fwsignal.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
index d7c36af4b566..ce8c6ceafc58 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
@@ -323,6 +323,10 @@ struct brcmf_skbuff_cb {
* firmware suppress the packet as device is already in PS mode.
* @BRCMF_FWS_TXSTATUS_FW_TOSSED:
* firmware tossed the packet.
+ * @BRCMF_FWS_TXSTATUS_FW_DISCARD_NOACK:
+ * firmware tossed the packet after retries.
+ * @BRCMF_FWS_TXSTATUS_FW_SUPPRESS_ACKED:
+ * firmware wrongly reported suppressed previously, now fixing to acked.
* @BRCMF_FWS_TXSTATUS_HOST_TOSSED:
* host tossed the packet.
*/
@@ -331,6 +335,8 @@ enum brcmf_fws_txstatus {
BRCMF_FWS_TXSTATUS_CORE_SUPPRESS,
BRCMF_FWS_TXSTATUS_FW_PS_SUPPRESS,
BRCMF_FWS_TXSTATUS_FW_TOSSED,
+ BRCMF_FWS_TXSTATUS_FW_DISCARD_NOACK,
+ BRCMF_FWS_TXSTATUS_FW_SUPPRESS_ACKED,
BRCMF_FWS_TXSTATUS_HOST_TOSSED
};
@@ -1455,6 +1461,10 @@ brcmf_fws_txs_process(struct brcmf_fws_info *fws, u8 flags, u32 hslot,
remove_from_hanger = false;
} else if (flags == BRCMF_FWS_TXSTATUS_FW_TOSSED)
fws->stats.txs_tossed += compcnt;
+ else if (flags == BRCMF_FWS_TXSTATUS_FW_DISCARD_NOACK)
+ fws->stats.txs_discard += compcnt;
+ else if (flags == BRCMF_FWS_TXSTATUS_FW_SUPPRESS_ACKED)
+ fws->stats.txs_discard += compcnt;
else if (flags == BRCMF_FWS_TXSTATUS_HOST_TOSSED)
fws->stats.txs_host_tossed += compcnt;
else
--
2.25.0
From: Double Lo <[email protected]>
This patch move the credit map setting to right place to avoid
brcmf_fws_return_credits() return without setting the credit map.
It fix the thoughput zero stalls issue in softAP mode when STA
using PM 1 mode.
Signed-off-by: Double Lo <[email protected]>
Signed-off-by: Chi-hsien Lin <[email protected]>
---
drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
index ce8c6ceafc58..ab4526223a93 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
@@ -1193,6 +1193,8 @@ static void brcmf_fws_return_credits(struct brcmf_fws_info *fws,
if (!credits)
return;
+ fws->fifo_credit_map |= 1 << fifo;
+
if (fifo > BRCMF_FWS_FIFO_AC_BK &&
fifo <= BRCMF_FWS_FIFO_AC_VO) {
for (lender_ac = BRCMF_FWS_FIFO_AC_VO; lender_ac >= 0;
@@ -1216,7 +1218,6 @@ static void brcmf_fws_return_credits(struct brcmf_fws_info *fws,
if (credits) {
fws->fifo_credit[fifo] += credits;
- fws->fifo_credit_map |= 1 << fifo;
}
if (fws->fifo_credit[fifo] > fws->init_fifo_credit[fifo])
--
2.25.0
From: Jia-Shyr Chuang <[email protected]>
In wifi firmware, max length of IOCTL/IOVAR buffer size is 8192.
Increase the message buffer max size same as wifi firmware for control
packets so return buffers can come back.
Signed-off-by: Soontak Lee <[email protected]>
Signed-off-by: Jia-Shyr Chuang <[email protected]>
Signed-off-by: Chi-Hsien Lin <[email protected]>
---
drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
index 8bb4f1fa790e..f1a20db8daab 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
@@ -54,6 +54,7 @@
#define BRCMF_IOCTL_REQ_PKTID 0xFFFE
#define BRCMF_MSGBUF_MAX_PKT_SIZE 2048
+#define BRCMF_MSGBUF_MAX_CTL_PKT_SIZE 8192
#define BRCMF_MSGBUF_RXBUFPOST_THRESHOLD 32
#define BRCMF_MSGBUF_MAX_IOCTLRESPBUF_POST 8
#define BRCMF_MSGBUF_MAX_EVENTBUF_POST 8
@@ -1028,7 +1029,7 @@ brcmf_msgbuf_rxbuf_ctrl_post(struct brcmf_msgbuf *msgbuf, bool event_buf,
rx_bufpost = (struct msgbuf_rx_ioctl_resp_or_event *)ret_ptr;
memset(rx_bufpost, 0, sizeof(*rx_bufpost));
- skb = brcmu_pkt_buf_get_skb(BRCMF_MSGBUF_MAX_PKT_SIZE);
+ skb = brcmu_pkt_buf_get_skb(BRCMF_MSGBUF_MAX_CTL_PKT_SIZE);
if (skb == NULL) {
bphy_err(drvr, "Failed to alloc SKB\n");
--
2.25.0
From: Joseph Chuang <[email protected]>
Commit 9c29da3f4e7e
("brcmfmac: Fix P2P Group Formation failure via Go-neg method") did not
initialize requested_dwell properly, resulting in an always-false dwell
time overflow check. Fix it by setting the correct requested_dwell
value.
Fixes: 4905432b28b7 ("brcmfmac: Fix P2P Group Formation failure via Go-neg method")
Signed-off-by: Joseph Chuang <[email protected]>
Signed-off-by: Chi-Hsien Lin <[email protected]>
---
drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 2 +-
drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c | 5 ++---
2 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
index a757abd7a599..bddd23240609 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
@@ -5129,7 +5129,7 @@ brcmf_cfg80211_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
&freq);
chan_nr = ieee80211_frequency_to_channel(freq);
af_params->channel = cpu_to_le32(chan_nr);
-
+ af_params->dwell_time = cpu_to_le32(params->wait);
memcpy(action_frame->data, &buf[DOT11_MGMT_HDR_LEN],
le16_to_cpu(action_frame->len));
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
index d2795dc17c46..debd887e159e 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c
@@ -1700,7 +1700,7 @@ static s32 brcmf_p2p_pub_af_tx(struct brcmf_cfg80211_info *cfg,
return err;
}
-static bool brcmf_p2p_check_dwell_overflow(s32 requested_dwell,
+static bool brcmf_p2p_check_dwell_overflow(u32 requested_dwell,
unsigned long dwell_jiffies)
{
if ((requested_dwell & CUSTOM_RETRY_MASK) &&
@@ -1738,8 +1738,7 @@ bool brcmf_p2p_send_action_frame(struct brcmf_cfg80211_info *cfg,
unsigned long dwell_jiffies = 0;
bool dwell_overflow = false;
- s32 requested_dwell = af_params->dwell_time;
-
+ u32 requested_dwell = le32_to_cpu(af_params->dwell_time);
action_frame = &af_params->action_frame;
action_frame_len = le16_to_cpu(action_frame->len);
--
2.25.0
Chi-Hsien Lin <[email protected]> writes:
> From: Amar Shankar <[email protected]>
>
> It is observed that sometimes when sdiod is low in tx credits in low
> rssi scenarios, the data path consumes all sdiod rx all credits and
> there is no sdiod rx credit available for control path causing host
> and card to go out of sync resulting in link loss between host and
> card. So in order to prevent it some credits are reserved for control
> path.
>
> Note that TXCTL_CREDITS can't be larger than the firmware default
> credit update threshold 2; otherwise there will be a deadlock for both
> side waiting for each other.
>
> Signed-off-by: Amar Shankar <[email protected]>
> Signed-off-by: Jia-Shyr Chuang <[email protected]>
> Signed-off-by: Chi-Hsien Lin <[email protected]>
> ---
> .../wireless/broadcom/brcm80211/brcmfmac/sdio.c | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> index ce6f15284277..163bb7f41e44 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
> @@ -635,6 +635,8 @@ static const struct brcmf_firmware_mapping brcmf_sdio_fwnames[] = {
> BRCMF_FW_ENTRY(CY_CC_43012_CHIP_ID, 0xFFFFFFFF, 43012)
> };
>
> +#define TXCTL_CREDITS 2
> +
> static void pkt_align(struct sk_buff *p, int len, int align)
> {
> uint datalign;
> @@ -647,6 +649,14 @@ static void pkt_align(struct sk_buff *p, int len, int align)
>
> /* To check if there's window offered */
> static bool data_ok(struct brcmf_sdio *bus)
> +{
> + /* Reserve TXCTL_CREDITS credits for txctl */
> + return (u8)(bus->tx_max - bus->tx_seq) > TXCTL_CREDITS &&
> + ((u8)(bus->tx_max - bus->tx_seq) & 0x80) == 0;
> +}
Why casting to u8? Is it really necessary?
--
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
On 06/09/2020 7:51, Kalle Valo wrote:
> Chi-Hsien Lin <[email protected]> writes:
>
>> From: Amar Shankar <[email protected]>
>>
>> It is observed that sometimes when sdiod is low in tx credits in low
>> rssi scenarios, the data path consumes all sdiod rx all credits and
>> there is no sdiod rx credit available for control path causing host
>> and card to go out of sync resulting in link loss between host and
>> card. So in order to prevent it some credits are reserved for control
>> path.
>>
>> Note that TXCTL_CREDITS can't be larger than the firmware default
>> credit update threshold 2; otherwise there will be a deadlock for both
>> side waiting for each other.
>>
>> Signed-off-by: Amar Shankar <[email protected]>
>> Signed-off-by: Jia-Shyr Chuang <[email protected]>
>> Signed-off-by: Chi-Hsien Lin <[email protected]>
>> ---
>> .../wireless/broadcom/brcm80211/brcmfmac/sdio.c | 15 ++++++++++++++-
>> 1 file changed, 14 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
>> index ce6f15284277..163bb7f41e44 100644
>> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
>> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
>> @@ -635,6 +635,8 @@ static const struct brcmf_firmware_mapping brcmf_sdio_fwnames[] = {
>> BRCMF_FW_ENTRY(CY_CC_43012_CHIP_ID, 0xFFFFFFFF, 43012)
>> };
>>
>> +#define TXCTL_CREDITS 2
>> +
>> static void pkt_align(struct sk_buff *p, int len, int align)
>> {
>> uint datalign;
>> @@ -647,6 +649,14 @@ static void pkt_align(struct sk_buff *p, int len, int align)
>>
>> /* To check if there's window offered */
>> static bool data_ok(struct brcmf_sdio *bus)
>> +{
>> + /* Reserve TXCTL_CREDITS credits for txctl */
>> + return (u8)(bus->tx_max - bus->tx_seq) > TXCTL_CREDITS &&
>> + ((u8)(bus->tx_max - bus->tx_seq) & 0x80) == 0;
>> +}
>
> Why casting to u8? Is it really necessary?
I don't think the casting is necessary since tx_max and tx_seq are both u8.
The code is taken from a similar function data_ok(). I'll remove the
casting from both functions in V2.
>