git: 654cffe59dd6 - main - LinuxKPI: 802.11: implement cfg80211_calculate_bitrate()

The branch main has been updated by bz:

URL: https://cgit.FreeBSD.org/src/commit/?id=654cffe59dd6c8818241bf44eff333af28e10168

commit 654cffe59dd6c8818241bf44eff333af28e10168
Author:     Bjoern A. Zeeb <bz@FreeBSD.org>
AuthorDate: 2026-08-29 01:56:55 +0000
Commit:     Bjoern A. Zeeb <bz@FreeBSD.org>
CommitDate: 2026-08-31 21:42:37 +0000

    LinuxKPI: 802.11: implement cfg80211_calculate_bitrate()
    
    lkpi_cfg80211_calculate_bitrate_vht() was constantly showing up
    in my debug traces as a TODO with rtw89 so I went ahead and implemented
    the HT and VHT versions.  Realtek seems to limit amsdu sizes based
    on the value and ask for it whether needed or not.
    
    Sponsored by:   The FreeBSD Foundation
    MFC after:      3 days
---
 sys/compat/linuxkpi/common/src/linux_80211.c | 109 ++++++++++++++++++++++++++-
 1 file changed, 105 insertions(+), 4 deletions(-)

diff --git a/sys/compat/linuxkpi/common/src/linux_80211.c b/sys/compat/linuxkpi/common/src/linux_80211.c
index f1eef91af0da..ae0c374e2ea6 100644
--- a/sys/compat/linuxkpi/common/src/linux_80211.c
+++ b/sys/compat/linuxkpi/common/src/linux_80211.c
@@ -8845,15 +8845,116 @@ linuxkpi_80211_wiphy_register(struct wiphy *wiphy)
 static uint32_t
 lkpi_cfg80211_calculate_bitrate_ht(struct rate_info *rate)
 {
-	TODO("cfg80211_calculate_bitrate_ht");
-	return (rate->legacy);
+	/*
+	 * IEEE Std 802.11-2024, 19.5 Parameters for HT-MCSs;
+	 * Tables Table 19-27-MCS NSS=1 800ns GI, and following.
+	 * We use 100Kbit/s entries, the expacted return scale.
+	 * We can calulate MCS0..31 entries.
+	 */
+	uint32_t r;
+	uint8_t nss, mcsidx;
+
+	if (rate->mcs > 31)
+		goto inval;
+
+	switch (rate->bw) {
+	case RATE_INFO_BW_20:
+		r = 65;
+		break;
+	case RATE_INFO_BW_40:
+		r = 135;
+		break;
+	default:
+		goto inval;
+		/* NOTREACHED */
+	}
+
+	nss = (rate->mcs >> 3) + 1;
+	mcsidx = rate->mcs & 0x07;
+
+	switch (mcsidx) {
+	case 0 ... 3:
+		r *= (mcsidx + 1);
+		break;
+	case 4:
+		r *= (mcsidx + 2);
+		break;
+	case 5 ... 7:
+		r *= (mcsidx + 3);
+		break;
+	default:
+		goto inval;
+		/* NOTREACHED */
+	}
+	r *= nss;
+	if ((rate->flags & RATE_INFO_FLAGS_SHORT_GI) != 0)
+		r = (r * 10) / 9;
+
+	return (r);
+
+inval:
+	/* Do not warn every time or we get too much spam on console! */
+	WARN_ONCE(1, "%s: rate mcs %u nss %u mcsidx %u invalid!\n",  __func__,
+	    rate->mcs, nss, mcsidx);
+	return (0);
 }
 
 static uint32_t
 lkpi_cfg80211_calculate_bitrate_vht(struct rate_info *rate)
 {
-	TODO("cfg80211_calculate_bitrate_vht");
-	return (rate->legacy);
+	/*
+	 * IEEE Std 802.11-2024, 21.5 Parameters for VHT-MCSs;
+	 * Tables 21-29 NSS=1 800ns GI, and following.
+	 * We use 100Kbit/s entries, the expacted return scale.
+	 */
+	static const uint16_t datarate[4][10] = {
+		/* BW20 */
+		{ 65, 130, 195, 260, 390, 520, 585, 650, 780, 0 },
+		/* BW40 */
+		{ 135, 270, 405, 540, 810, 1080, 1215, 1350, 1620, 1800 },
+		/* BW80 */
+		{ 293, 585, 878, 1170, 1755, 2340, 2633, 2925, 3510, 3900 },
+		/* BW160 */
+		{ 585, 1170, 1755, 2340, 3510, 4680, 5265, 5850, 7020, 7800 }
+	};
+	uint32_t r;
+	uint8_t bwidx;
+
+	/* Should we warn about out of bounds values? */
+	if (rate->mcs > 9 || rate->nss > 8)
+		goto inval;
+
+	switch (rate->bw) {
+	case RATE_INFO_BW_20:
+		bwidx = 0;
+		break;
+	case RATE_INFO_BW_40:
+		bwidx = 1;
+		break;
+	case RATE_INFO_BW_80:
+		bwidx = 2;
+		break;
+	case RATE_INFO_BW_160:
+		bwidx = 2;
+		break;
+	default:
+		goto inval;
+		/* NOTREACHED */
+	}
+
+	r = datarate[bwidx][rate->mcs];
+	/* Calculate the other NSS tables and the SGI column. */
+	r *= rate->nss;
+	if ((rate->flags & RATE_INFO_FLAGS_SHORT_GI) != 0)
+		r = (r * 10) / 9;
+
+	return (r);
+
+inval:
+	/* Do not warn every time or we get too much spam on console! */
+	WARN_ONCE(1, "%s: rate mcs %u nss %u bw %d (%s) invalid!\n",  __func__,
+	    rate->mcs, rate->nss, rate->bw, lkpi_rate_info_bw_to_str(rate->bw));
+	return (0);
 }
 
 uint32_t