Vivado的圖形化的模塊設(shè)計(jì)，豐富的IP庫，加上可以上天的智能連接。有點(diǎn)數(shù)字電路設(shè)計(jì)的基礎(chǔ)，很快就能完成這個(gè)小設(shè)計(jì)。整個(gè)設(shè)計(jì)如下圖。點(diǎn)贊！

軟件設(shè)計(jì)
這里用到Xilinx針對Linux BSP開發(fā)的Petalinux。它基于Yocto，加入Xilinx的Layers實(shí)現(xiàn)硬件工程的導(dǎo)入，將復(fù)雜的Yocto的設(shè)計(jì)流程打包簡化，支持一定的用戶自定義功能，如QEMU仿真運(yùn)行，增加out-of-tree的驅(qū)動(dòng)，Device tree修改，應(yīng)用程序編譯打包，等等。這里簡單展示一下具體的命令過程。

$petalinux-create -t project --template zynqMP -n zcu102-pl2ps_irq
$cd ./ zcu102-pl2ps_irq
$petalinux-config --get-hw-description
$petalinux-config -c kernel
Enable UIO_PDRV_GENIRQ driver
CONFIG_UIO=y
# CONFIG_UIO_CIF is not set
CONFIG_UIO_PDRV_GENIRQ=y
$petalinux-build -c device-tree

PL側(cè)的dtsi文件生成與./components/plnx_workspace/device-tree-generation/pl.dtsi

這里只有GPIO UIO。PIN UIO因?yàn)椴皇荌P，所以相關(guān)信息無法由工具自動(dòng)生成。所以要做如下修改，
1.修改GPIO UIO設(shè)備端點(diǎn)
a)將中斷號(hào)改為93
b)將compatible改成“generic-uio” //我們后面要用Linux自帶的UIO_PDRV_GENIRQ驅(qū)動(dòng)
2.增加DIP UIO端點(diǎn)
a)將compatible改成“generic-uio”
b)依次設(shè)置中斷值89到93
c)按照每個(gè)DIP PIN的interrupt trigger type設(shè)置屬性值

*DTS里的中斷號(hào)與硬件中斷號(hào)有32的offset。
Petalinux提供了自定義DTS文件./project-spec/meta-user/recipes-bsp/device-tree/files/system-user.dtsi，將以上修改定義到system-user.dtsi.

有兩個(gè)方法來適配UIO端點(diǎn)和 UIO_PDRV_GENIRQ 驅(qū)動(dòng)
1. bootargs use“uio_pdrv_genirq.of_id=generic-uio”，可以通過DTS定義。
2. insmod uio_pdrv_genirq.ko of_id=generic-uiowhen install the driver

修改完后，編譯出Image.
$petalinu-build
$cd ./images/linux
$petalinux-package --boot--fsbl zynqmp_fsbl.elf --fpga --atf --pmufw --u-boot --force

將生成的BOOT.bin（bootloader）和image.ub(FIT uImage)拷貝到SD卡用于啟動(dòng)。

測試

這里引用下關(guān)于uio_pdrv_genirq驅(qū)動(dòng)的介紹
https://01.org/linuxgraphics/gfx-docs/drm/driver-api/uio-howto.html

Using uio_pdrv_genirq for platform devices
Especially in embedded devices, you frequently find chips where the irq pin is tied to its own dedicated interrupt line. In such cases, where you can be really sure the interrupt is not shared, we can take the concept of uio_pdrv one step further and use a generic interrupt handler. That’s what uio_pdrv_genirq does.
The setup for this driver is the same as described above for uio_pdrv, except that you do not implement an interrupt handler. The .handler element of struct uio_info must remain NULL. The .irq_flags element must not contain IRQF_SHARED.
You will set the .name element of struct platform_device to "uio_pdrv_genirq" to use this driver.
The generic interrupt handler of uio_pdrv_genirq will simply disable the interrupt line using disable_irq_nosync(). After doing its work, userspace can reenable the interrupt by writing 0x00000001 to the UIO device file. The driver already implements an irq_control() to make this possible, you must not implement your own.
Using uio_pdrv_genirq not only saves a few lines of interrupt handler code. You also do not need to know anything about the chip’s internal registers to create the kernel part of the driver. All you need to know is the irq number of the pin the chip is connected to.

在結(jié)合驅(qū)動(dòng)代碼./drviver/uio/uio_pdrv_genirq.c)可知，每個(gè)UIO設(shè)備會(huì)有對應(yīng)的/dev/uioX的設(shè)備節(jié)點(diǎn)。用戶態(tài)驅(qū)動(dòng)程序的讀操作會(huì)阻塞直到UIO硬件中斷發(fā)生。UIO的中斷處理程序uio_pdrv_denirq_handler()會(huì)關(guān)閉該硬件中斷。用戶態(tài)驅(qū)動(dòng)程序需要通過write函數(shù)來觸發(fā)uio_pdrv_genirq_irqcontrol()以完成中斷的使能和關(guān)閉。代碼如下,

啟動(dòng)內(nèi)核及加載uio_pdrv_genirq驅(qū)動(dòng)

檢查/proc/interrupts