Compared to fixed payload packets, random payload packets have better
measured EVM under the same txpower. Our tests show EVM becomes at least
2-3 dB better in test cases with high rate and long tx length, which also
aligns the testing results to proprietary driver.
Suggested-by: Jm Chen <jm.chen@xxxxxxxxxxxx>
Signed-off-by: Shayne Chen <shayne.chen@xxxxxxxxxxxx>
---
drivers/net/wireless/mediatek/mt76/testmode.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/testmode.c b/drivers/net/wireless/mediatek/mt76/testmode.c
index 47ac0ca1af32..fedc7a61ca37 100644
--- a/drivers/net/wireless/mediatek/mt76/testmode.c
+++ b/drivers/net/wireless/mediatek/mt76/testmode.c
@@ -1,5 +1,7 @@
// SPDX-License-Identifier: ISC
/* Copyright (C) 2020 Felix Fietkau <nbd@xxxxxxxx> */
+
+#include <linux/random.h>
#include "mt76.h"
const struct nla_policy mt76_tm_policy[NUM_MT76_TM_ATTRS] = {
@@ -124,12 +126,14 @@ int mt76_testmode_alloc_skb(struct mt76_phy *phy, u32 len)
if (!head)
return -ENOMEM;
- hdr = __skb_put_zero(head, head_len);
+ hdr = __skb_put_zero(head, sizeof(*hdr));
hdr->frame_control = cpu_to_le16(fc);
memcpy(hdr->addr1, td->addr[0], ETH_ALEN);
memcpy(hdr->addr2, td->addr[1], ETH_ALEN);
memcpy(hdr->addr3, td->addr[2], ETH_ALEN);
skb_set_queue_mapping(head, IEEE80211_AC_BE);
+ get_random_bytes(__skb_put(head, head_len - sizeof(*hdr)),
+ head_len - sizeof(*hdr));
info = IEEE80211_SKB_CB(head);
info->flags = IEEE80211_TX_CTL_INJECTED |
@@ -157,7 +161,7 @@ int mt76_testmode_alloc_skb(struct mt76_phy *phy, u32 len)
return -ENOMEM;
}
- __skb_put_zero(frag, frag_len);
+ get_random_bytes(__skb_put(frag, frag_len), frag_len);
head->len += frag->len;
head->data_len += frag->len;
--
2.25.1
