On Thu, Aug 18, 2016 at 11:57:29AM +0200, Mark Kettenis wrote: > > Date: Thu, 18 Aug 2016 11:41:52 +0200 > > From: Marcus Glocker <mar...@nazgul.ch> > > > > On Wed, Aug 17, 2016 at 04:05:05PM +0200, Mark Kettenis wrote: > > > > > > Date: Wed, 17 Aug 2016 15:36:21 +0200 > > > > From: Marcus Glocker <mar...@nazgul.ch> > > > > > > > > Enables FIFO for Synopsis DesignWare APB UART. > > > > > > > > ok? > > > > > > Apparently the FIFO is optional. There is a register that tells you > > > whether it is enabled or not. Not sure we'll ever encounter an > > > implementation that has that option turned off. But we probably > > > should check to be sure. > > > > Ok. This updated diff tries to find out about FIFO support by reading > > the CPR registers FIFO_MODE field. If it contains zero, no FIFO > > support, otherwise it conains the supported FIFO depth. > > > > Unfortunately on my allwinner,sun5i-r8 it returns zero which suprises > > me a bit. Therefore it would be interessting if it could be tested on > > other sunxi boards as well to see whether it returns non-zero there and > > hence you should find a com-line showing the FIFO size. > > Same on allwinner,sun8i-a20. The data sheet says there is a 64-byte > FIFO, but they have conveniently disabled the registers that tell you > that! Not sure to what extent we should trust the data sheet though. > This is cheap Chinese hardware in the end. Probably best to leave > things as they are right now. Unless you move large volumes of data, > the FIFO isn't terribly important I'd say.
Ok, fine, I agree.
