On Wed, Oct 17, 2012 at 2:48 AM, Wolfgang Denk wd@denx.de wrote:
CONFIG_ISP1362_USB is an option used only in the respective board config files, used there to set up a mapping for the respective device memory; if enabled, we define CONFIG_SYS_BR5_ISP1362 and CONFIG_SYS_OR5_ISP1362 which are then used in the code to program the memory controller of the SoC used on these boards as needed; see "board/tqc/tqm8xx/tqm8xx.c"
That part is clear to me. I don't think I need to do that on the Blackfin, as the external chip selects have pre-defined addresses (and it doesn't have a MMU).
...And there is no way it could work without using them as the ISP1362 sits on the data bus as a memory-mapped part and the driver would need to know where to find it.
Well, the memory controller does get programmed for a valid mapping, see "board/tqc/tqm8xx/tqm8xx.c"...this really only makes sure the device is mapped at the right address. But you are right - I don't even see USB enabled in the NSCU board config file. eventually all that gets done is setting up the memory controller (for later use in Linux?).
Now that you mention it, it makes sense that they are just setting things up for later use in Linux. I guess I followed a major bunny trail thinking it did more.
If I were to pursue adding ISP1362 support to U-Boot, would it be best to port the Linux driver or is there another way? Would that support need to be built on top of something else like EHCI, or would it sit in parallel with it? FWIW, I think that the ISP1362 Linux driver supports only host mode (not gadget or OTG).
Thank you very much for clearing up my confusion and ending my search for the driver that apparently doesn't exist.
Steve