cfg80211: Add support to calculate and report 4096-QAM HE rates

Drivers supporting 4096-QAM rates as a vendor extension in HE mode need
to update the correct rate info to userspace while using 4096-QAM (MCS12
and MCS13) in HE mode. Add support to calculate bitrates of HE-MCS12 and
HE-MCS13 which represent the 4096-QAM modulation schemes. The MCS12 and
MCS13 bitrates are defined in IEEE P802.11be/D0.1.

In addition, scale up the bitrates by 3*2048 in order to accommodate
calculations for the new MCS12 and MCS13 rates without losing fraction
values.

Signed-off-by: Vamsi Krishna <vamsin@codeaurora.org>
Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Link: https://lore.kernel.org/r/20201029183457.7005-1-jouni@codeaurora.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/wireless/util.c b/net/wireless/util.c
index f017468..5b6c80a 100644 (file)
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1276,20 +1276,22 @@ static u32 cfg80211_calculate_bitrate_vht(struct rate_info *rate)
 
 static u32 cfg80211_calculate_bitrate_he(struct rate_info *rate)
 {
-#define SCALE 2048
-       u16 mcs_divisors[12] = {
-               34133, /* 16.666666... */
-               17067, /*  8.333333... */
-               11378, /*  5.555555... */
-                8533, /*  4.166666... */
-                5689, /*  2.777777... */
-                4267, /*  2.083333... */
-                3923, /*  1.851851... */
-                3413, /*  1.666666... */
-                2844, /*  1.388888... */
-                2560, /*  1.250000... */
-                2276, /*  1.111111... */
-                2048, /*  1.000000... */
+#define SCALE 6144
+       u32 mcs_divisors[14] = {
+               102399, /* 16.666666... */
+                51201, /*  8.333333... */
+                34134, /*  5.555555... */
+                25599, /*  4.166666... */
+                17067, /*  2.777777... */
+                12801, /*  2.083333... */
+                11769, /*  1.851851... */
+                10239, /*  1.666666... */
+                 8532, /*  1.388888... */
+                 7680, /*  1.250000... */
+                 6828, /*  1.111111... */
+                 6144, /*  1.000000... */
+                 5690, /*  0.926106... */
+                 5120, /*  0.833333... */
        };
        u32 rates_160M[3] = { 960777777, 907400000, 816666666 };
        u32 rates_969[3] =  { 480388888, 453700000, 408333333 };
@@ -1301,7 +1303,7 @@ static u32 cfg80211_calculate_bitrate_he(struct rate_info *rate)
        u64 tmp;
        u32 result;
 
-       if (WARN_ON_ONCE(rate->mcs > 11))
+       if (WARN_ON_ONCE(rate->mcs > 13))
                return 0;
 
        if (WARN_ON_ONCE(rate->he_gi > NL80211_RATE_INFO_HE_GI_3_2))