[U-Boot-Users] U-BOOT and UART TX with interrupts (need help please)

[Jerry Van Baren]

veter wrote:
> wd wrote:
>> In message <12896654.post at talk.nabble.com> you wrote:
>>> Our program based on U-BOOT and we need transmit data at UART-TX with
>>> interrupts.
>> What makes you think you need interrupts? U-Boot is  strictly  single
>> tasking,  so  it will not do anything else anyway while transmitting,
>> and even a very slow CPU should be capable  of  streaming  characters
>> out or an UART then.
>>
>>> But, as we understand, U-BOOT do not have "API" for correct realization
>>> Interrupts, we fount in cpu/bf532/serial.c each initialization with as-be
>>> usage Interrupts, but not used it, because only doing looping ISR
>>> register
>>> on FLAG IRQ_UART_TX_BIT.
>> Indeed polling is all you need.
>>
>>> It is not correct usage Interrupts. We need full usage interrupts.
>> What makes you think so? Interrupts will not give you any advantages.
>>
>> Best regards,
>>
>> Wolfgang Denk
> 
> I greet you!
> It is hope for your help!
> 
> The fact is that we have decided to base / Platform U-BOOT make its program
> to develop so it is ready realizovanno many software tools.
> 
> Interruption we need to make our CPU BlackFin we can use with DMA capability
> and maximize productivity gains.
> 
> Core, we want to use and abandonment of the CPU and DMA (BlackFin 532).
> In fact, we will have passed a very big massyvy in UART and use DMA, we will
> win big, because 90% of CPU performance will be employed mathematical
> calculations.
> 
> For that reason has much to use the lack of interruption, please help!

Please don't top post.

U-Boot is a boot loader, used to
* Initialize the hardware
* Load an operating system
* Start the operating system running

You are looking for an operating system with interrupts and possibly 
multi-tasking.  U-Boot may be helpful in *loading and starting* your 
operating system, but it is *not* an operating system.  It does not 
normally use, and thus has no support for, interrupts.

Best regards,
gvb