8857481840
The Zynq/Zedboard GPIO driver attempts to tri-state all GPIO pins on boot up but the order in which I reset the hardware can cause the pins to be briefly held low before being tri-stated. This is a problem on boards that use GPIO pins to reset devices. In particular, the Zybo and ZC-706 boards use a GPIO pin as a USB PHY reset. If U-boot enables the USB port before booting the kernel, the GPIO driver attach causes a glitch on the USB PHY reset and the USB port loses power. My fix is to have the GPIO driver leave the pins in whatever configuration U-boot placed them. PR: 225713 Submitted by: Thomas Skibo <thoma555-bsd@yahoo.com> MFC after: 1 week |
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files.zynq7 | ||
std.zynq7 | ||
uart_dev_cdnc.c | ||
zy7_devcfg.c | ||
zy7_ehci.c | ||
zy7_gpio.c | ||
zy7_l2cache.c | ||
zy7_machdep.c | ||
zy7_machdep.h | ||
zy7_mp.c | ||
zy7_reg.h | ||
zy7_slcr.c | ||
zy7_slcr.h |