wget „https://github.com/openwrt/openwrt/archive/v18.06.1.tar.gz“ (or even better whole SDK: https://downloads.openwrt.org/releases/19.07.4/targets/mvebu/cortexa9/openwrt-sdk-19.07.4-mvebu-cortexa9_gcc-7.5.0_musl_eabi.Linux-x86_64.tar.xz)
tar zxf v18.06.1.tar.gz
ls
cd openwrt-18.06.1/ 1024 ls
1025 ./scripts/feeds update base
1026 ./scripts/feeds install mwlwifi

by making menuconfig deselect all you dont need

make package/kernel/mwlwifi/download
make package/kernel/mwlwifi/compile
make package/kernel/mwlwifi/install
make package/index

diff –git a/hif/pcie/pcie.c b/hif/pcie/pcie.c
index da55913..1f5af72 100644
— a/hif/pcie/pcie.c +++ b/hif/pcie/pcie.c
@@ -455,10 +455,10 @@ static irqreturn_t pcie_isr(struct ieee80211_hw *hw)
  }
  }

- if (int_status & MACREG_A2HRIC_BIT_RADAR_DETECT) { - wiphy_info(hw→wiphy, „radar detected by firmware\n“); - ieee80211_radar_detected(hw); - } + if (int_status & MACREG_A2HRIC_BIT_RADAR_DETECT) {
+
wiphy_info(hw→wiphy, „radar detected by firmware\n“);
+ ieee80211_radar_detected(hw);
+
}

  if (int_status & MACREG_A2HRIC_BIT_QUE_EMPTY) {
  if (!pcie_priv→is_qe_schedule) {
@@ -922,10 +922,10 @@ static irqreturn_t pcie_isr_ndp(struct ieee80211_hw *hw)
  }
  }

- if (int_status & MACREG_A2HRIC_NEWDP_DFS) { - wiphy_info(hw→wiphy, „radar detected by firmware\n“); - ieee80211_radar_detected(hw); - } + if (int_status & MACREG_A2HRIC_NEWDP_DFS) {
+
wiphy_info(hw→wiphy, „radar detected by firmware\n“);
+ ieee80211_radar_detected(hw);
+
}

  if (int_status & MACREG_A2HRIC_NEWDP_CHANNEL_SWITCH)
  ieee80211_queue_work(hw, &priv→chnl_switch_handle);

https://github.com/kaloz/mwlwifi/blob/417c15f2af00920945882a1b82ab1f5785a7b7b0/README.md#note-for-dfs-of-wrt3200acm-88w8964

opkg remove kmod-mwifiex-sdio
opkg remove mwifiex-sdio-firmware


Download SDK
wget „https://downloads.openwrt.org/releases/21.02.2/targets/mvebu/cortexa9/openwrt-sdk-21.02.2-mvebu-cortexa9_gcc-8.4.0_musl_eabi.Linux-x86_64.tar.xz
./scripts/feeds update base
./scripts/feeds install mwlwifi
make ./package/feeds/base/mwlwifi/download
change the pcie.c
tar xf mwlwifi-2020-02-06-a2fd00bb.tar.xz
tar -cJf mwlwifi-2020-02-06-a2fd00bb.tar.xz mwlwifi-2020-02-06-a2fd00bb
sha256sum mwlwifi-2020-02-06-a2fd00bb.tar.xz
update hashes in Makefiles
vi ./package/feeds/base/mwlwifi/Makefile
make -j33 ./package/feeds/base/mwlwifi/compile
vi ./feeds/base/package/kernel/mwlwifi/Makefile