Hi Tim, On Wed, Oct 7, 2015 at 11:26 PM, Timothy Scott <tescott...@gmail.com> wrote: > Bin, > > Thanks for the response. I've got things working with v2015.04, but it took > some tweaking. Here's what I learned: > > 1) PCI is initialized AFTER the code was attempting to configure hsuart0. > Since hsuart0 is on the PCI bus, the various registers being read were > coming up 0xFFFF and therefore hsuart0 access was invalid.
Yes, in v2015.04, Intel Crown Bay codes did this by defining CONFIG_SYS_EARLY_PCI_INIT and calling the PCI enumeration in arch_cpu_init() manually. With DM conversion on the latest u-boot/master branch, this is not needed as the enumeration will be triggered as needed. > 2) I'm swapping between PCU_UART (legac y) and SIO_UART at run-time, while > using the ns16550 driver in both instances. The code that underlies > ns16550_writeb() and ns16550_readb() expects things to be configured at > compile time via CONFIG options instead of something you can jack with at > run-time. > This can be enhanced by converting the ns16550 CONFIG options to a device tree bindings, however I don't know if there is any plan to do this. My only concern of doing it via device tree is that some performance degradation might be observed. > My workarounds: > - created hsuart_init() in serial-uclass.c, patterned off of > serial_find_console_or_panic(). This references a unique chosen option I > named "hsuart-path" and loads up hsuart device for me. I do this to get the > hsuart0 probed and loaded. (If there's a better way to force a device > probe, please let me know.) > - created initr_hsuart_serial() in board_r.c, and invoked this via the > init_sequence_r[] table, after initr_pci. > - updated ns16550.c's ns16550_platdata with a "mem_map" parameter. I added > a "mem-map" parm to the hsuart DTS entry, and load this value in via > ns16550_serial_ofdata_to_platdata. This is then referenced in > ns16550_writeb() and ns16550_readb() to perform a memory mapped access, > instead of whatever the CONFIG options have defined. In my case, CONFIG > options result in a port mapped access. > > All this is pretty hackish but works for my purposes. > > Thanks again, > --tim > > Regards, Bin _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
