Dear List: Hello.
I am in the middle of cooking up a V3s experiment board. For that board I want to allow the board to boot even without a microSD card installed. SD0 is the microSD slot, SD1 is being used to interface a SDIO Wi-Fi module, and only the SD2/SPI0 port is open. I know that I can just put an eMMC chip on SD2, but that seemed wasteful to me since that interface is limited to only 1-bit operation (while on my other board I has 8-bit eMMC on A13’s 8-bit SD2, making full use of it.) A cheaper alternative is using a 64MiB SPI NOR Flash as the onboard storage holding the complete OS and application image in it, but that would require u-boot support for SPI boot. How is the status of SPI in u-boot? Sincerely, Max p.s. Is it a good idea to share a single interrupt line for multiple devices, or should I use something like a PCF8574 on I2C bus as a “interrupt controller” of sorts? I ran out of interrupt lines since my board only ever had one to begin with, and from the mainline driver code that I2C I/O expander can function as a GPIO chip with an interrupt controller. -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
