[U-Boot] NS16550 Register structure

[Wolfgang Denk]

Dear "Pedanekar, Hemant",

In message <2A3DCF3DA181AD40BDE86A3150B27B6B03094B2982 at dbde02.ent.ti.com> you wrote:
> 
> I have observed that in the recent commit (file include/ns16550.h), the ns16550 UART register structure declaration is changed so that irrespective of the CONFIG_SYS_NS16550_REG_SIZE setting the register access will be done at byte level. 

This seems to be working on all systems so far, which is not so much
of a surprise as the registers are 8 bit wide only.

> This crates problem when UART space access is required to be word-aligned. I am particularly referring to DaVinci DM6467, where STRB over UART register space is not supported and requires 32-bit access (L/STR).

Please make sure to use exact terms. Alignment is one thing, and  bus
width  is  another  one.  Alignment  can be easily adjusted using the
prepad_* or postpad_* settings.

> If I go ahead and add a specific handling in ns16550.h file (structure register members as "long"), I would end up making code similar to the one earlier to last commit. Is there a better way to handle such case?

No such changes should be needed, as far as I understand the code.

Best regards,

Wolfgang Denk

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