Zynq SDIO WiFi
Introduction
The purpose of this page is to describe how to enable wireless connectivity for ZC702 running Linux.
HW/IP features
The two SDIO controllers are controlled and operate independently with the same feature set:
Host mode controller
- Four I/O signals (MIO or EMIO)
- Command, Clock, CD, WP, Pwr Ctrl (MIO or EMIO)
- LED control, bus voltage (EMIO)
- Interrupt or polling driven
- AHB master-slave interface operating at the CPU_1x clock rate
- Master mode for DMA transfers (with 1 KB FIFO)
- Slave mode for register accesses
SDIO Specification 2.0
- Low-speed, 1 KHz to 400 KHz
- Full-speed, 1 MHz to 50 MHz (25 MB/sec)
- High-speed and high-capacity memory cards
Features Supported by Driver
- All the HW/IP features are supported by driver
Missing features, Known Issues, Limitations
None
Kernel Configuration
-> Networking support (CONFIG_NET [=y]) -> Wireless (CONFIG_WIRELESS [=y]) -> cfg80211 (CONFIG_CFG80211 [=y])-> Device Drivers -> Generic Driver Options -> Userspace firmware loading support (CONFIG_FW_LOADER [=y]) -> Include in-kernel firmware blobs in kernel binary (CONFIG_FIRMWARE_IN_KERNEL [=n]) -> Network device support (CONFIG_NETDEVICES [=y]) -> Wireless LAN (CONFIG_WLAN [=y]) -> Atheros Wireless Cards (CONFIG_ATH_COMMON [=y]) -> Atheros mobile chipsets support (CONFIG_ATH6KL [=y]) -> Atheros ath6kl SDIO support (CONFIG_ATH6KL_SDIO [=m]) |
Devicetree
SD and eMMC
sdhci@ff160000 { compatible = "xlnx,zynqmp-8.9a", "arasan,sdhci-8.9a"; interrupt-parent = <&&gic>; interrupts = <0x0 0x30 0x4>; reg = <0x0 0xff160000 0x0 0x1000>; clock-names = "clk_xin", "clk_ahb"; xlnx,device_id = <0x0>;}; |
sdhci@ff170000 { compatible = "xlnx,zynqmp-8.9a", "arasan,sdhci-8.9a"; interrupt-parent = <&&gic>; interrupts = <0x0 0x31 0x4>; reg = <0x0 0xff170000 0x0 0x1000>; clock-names = "clk_xin", "clk_ahb"; xlnx,device_id = <0x0>;}; |
Test Procedure
Test Setup
Board: ZC702
Kernel: Linux 3.5 (uses uImage and uramdisk)
Wireless card in SDIO slot: Atheros AR6103 (see http://wireless.kernel.org/en/users/Drivers/Atheros)
Connection: Wired connection from host (192.168.1.2) to wireless access point (linksys, 192.168.1.1). Once the steps documented on this page have been followed, there will be a wireless connection between ZC702 (192.168.1.10) and the access point.
Boot Linux with Wireless Capabilities
Download and build Linux
See Getting Started for details on downloading and building Linux.
Download the latest Xilinx kernel:
bash> git clone git://github.com/Xilinx/linux-xlnx.git |
Configure the kernel for Zynq:
bash> make ARCH=arm xilinx_zynq_defconfig |
To compile the SDIO wireless driver as a loadable kernel module, configure the kernel:
bash> make ARCH=arm menuconfig |
Build the kernel and the driver:
bash> make ARCH=arm UIMAGE_LOADADDR=08000 uImagebash> make ARCH=arm modules |
Build the device tree blob:
bash> make ARCH=arm zynq-zc702.dtb |
Result:
<linux build dir>/drivers/net/wireless/ath/ath6kl/ath6kl_sdio.ko
<linux build dir>/arch/arm/boot/uImage
<linux build dir>/arch/arm/boot/zynq-zc702.dtb
Create a root filesystem
See Zynq Root File System to produce a root filesystem.
Add the following files to the root filesystem (refer to the Add Files to Running Linux page for instructions).
- Copy <linux build dir>/drivers/net/wireless/ath/ath6kl/ath6kl_sdio.ko to /root/ath6kl_sdio.koon the root filesystem (does not need to be located under /root).
- Cross-compile iwconfig (http://www.hpl.hp.com/personal/Jean_Tourrilhes/Linux/Tools.html) and copy it to the root filesystem (/usr/sbin).
- If using Buildroot to create the rootfs, the configuration option to install this is BR2_PACKAGE_WIRELESS_TOOLS.
Download the latest firmware:
bash> git clone git://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git |
Add the following files to the root filesystem (refer to the Add Files to Running Linux page for instructions).
- Copy <linux-firmware>/ath6k to /lib/firmware/ath6k on the root filesystem.
- Copy /lib/firmware/ath6k/AR6003/hw2.1.1/bdata.SD31.bin to /lib/firmware/ath6k/AR6003/hw2.1.1/bdata.bin on the root filesystem. The following result might occur otherwise (as of 2012/10/09):
ath6kl: Failed to get board file ath6k/AR6003/hw2.1.1/bdata.bin (-2), trying to find default board file.ath6kl: WARNING! No proper board file was not found, instead using a default board file.ath6kl: Most likely your hardware won't work as specified. Install correct board file! |
Result:
uramdisk.image.gz
Boot Linux on Zynq
-> ZC702 Boot From Flash for an example of how to boot from flash.
-> Boot From SD Card for an example of how to boot from an SD card.
*Note: Make sure to rename the device tree blob (*.dtb) to devicetree.dtb as this is what U-Boot expects for some of the boot modes (such as SD boot).
Enable wireless connectivity
Now that Linux is running on Zynq, it is time to enable wireless connectivity.
Load the wireless driver:
zynq> insmod /root/ath6kl_sdio.koath6kl: temporary war to avoid sdio crc errorath6kl: ar6003 hw 2.1.1 sdio fw 3.2.0.144 api 3 |
Setup wireless connection between the board and the host:
zynq> iwconfig wlan0 essid 'linksys'zynq> ifconfig wlan0 192.168.1.10 |
zynq> iwconfiglo no wireless extensions. wlan0 IEEE 802.11bgn ESSID:"linksys" Mode:Managed GEM: ioctl 35585 not implemented.Frequency:2.462 GHz Access Point: 00:16:B6:2A:AD:05 Bit Rate=54 Mb/s Tx-Power=15 dBm Retry long limit:7 RTS thr:off Fragment thr:off Encryption key:off Power Management:on Link Quality=62/70 Signal level=-48 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:0 Missed beacon:0 eth0 no wireless extensions. |
zynq> ifconfigeth0 Link encap:Ethernet HWaddr 00:0A:35:00:01:22 inet addr:10.10.71.1 Bcast:10.10.71.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:542 errors:0 dropped:0 overruns:0 frame:0 TX packets:124 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:753923 (736.2 KiB) TX bytes:14397 (14.0 KiB) Interrupt:54 Base address:0xb000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:12 errors:0 dropped:0 overruns:0 frame:0 TX packets:12 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:1020 (1020.0 B) TX bytes:1020 (1020.0 B) wlan0 Link encap:Ethernet HWaddr 00:03:7F:BE:F0:A0 inet addr:192.168.1.10 Bcast:10.255.255.255 Mask:255.0.0.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:31 errors:0 dropped:0 overruns:0 frame:0 TX packets:38 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4900 (4.7 KiB) TX bytes:4455 (4.3 KiB)[[#Enable wireless connectivity-Testing]] |
Expected Output
Now, there is a wireless connection between ZC702 and the host. This can be tested by issuing the following commands:
host> sftp root@192.168.1.10Connecting to 192.168.1.10...root@192.168.1.10's password: rootsftp> ls //README /ath6kl_sdio.ko /bin /dev /etc /home /lib/licenses /linuxrc /lost+found /mnt /opt /proc /root/sbin /sys /tmp /update_qspi.sh /usr /varsftp> |
