问题1：我们使用了WL1837的wifi模块，在进行性能测试的时候，发现其不能启动5G热点，信息如下：
root@NSC200:~# ./hostapd hostapd.conf
Configuration file: hostapd.conf
[ 2115.561118] wlcore: down
rfkill: Cannot open RFKILL control device
Channel 48 (primary) not allowed for AP mode, flags: 0x73 NO-IR
wlan0: IEEE 802.11 Configured channel (48) not found from the channel list of cu
rrent mode (2) IEEE 802.11a
wlan0: IEEE 802.11 Hardware does not support configured channel
Could not select hw_mode and channel. (-3)
wlan0: interface state UNINITIALIZED->DISABLED
wlan0: AP-DISABLED
wlan0: Unable to setup interface.
wlan0: interface state DISABLED->DISABLED
wlan0: AP-DISABLED
wlan0: CTRL-EVENT-TERMINATING
hostapd_free_hapd_data: Interface wlan0 wasn't started
nl80211: deinit ifname=wlan0 disabled_11b_rates=0
[ 2115.641454] wlcore: down
root@NSC200:~#
hostapd.conf 主要配置如下：
interface=wlan0
ssid=SC200-test
driver=nl80211
channel=48
ieee80211n=1
ieee80211ac=1
hw_mode=a
require_ht=1
ht_capab=[HT40-][HT40+][SHORT-GI-20][SHORT-GI-40]
问题2：在am335x平台，使用了WL1837的wifi模块，做2.4G热点的情况下，电脑用intel ax200 wifi连接，速率显示150M，实际下载速率不超过2.1MB/s；使用博通wifi 做5G热点的情况，连接速率433下，下载速率也不超过2.1MB/s，请问是SDIO接口速率限制了码?
