On Mon, Jan 7, 2019 at 11:58 PM Marek Vasut <ma...@denx.de> wrote: > > On 1/7/19 10:01 PM, Simon Goldschmidt wrote: > > Am 07.01.2019 um 21:47 schrieb Marek Vasut: > >> On 1/7/19 9:33 PM, Simon Goldschmidt wrote: > >>> Am 07.01.2019 um 21:25 schrieb Marek Vasut: > >>>> On 1/7/19 9:24 PM, Simon Goldschmidt wrote: > >>>>> Am 07.01.2019 um 21:19 schrieb Marek Vasut: > >>>>>> On 1/7/19 8:36 PM, Simon Goldschmidt wrote: > >>>>>>> When debug UART is enabled on socfpga_gen5, the debug uart driver > >>>>>>> hangs > >>>>>>> in an endless loop because 'socfpga_bridges_reset' calls printf > >>>>>>> before > >>>>>>> the debug UART is initialized. > >>>>>>> > >>>>>>> After the generic fix for this in the UART driver did not work > >>>>>>> due to > >>>>>>> portability issues, let's just drop this printf statement when > >>>>>>> called > >>>>>>> from SPL with debug UART enabled. > >>>>>>> > >>>>>>> Signed-off-by: Simon Goldschmidt <simon.k.r.goldschm...@gmail.com> > >>>>>> > >>>>>> Can we have an un-portable fix which at least works on SoCFPGA ? :) > >>>>> > >>>>> This one worked on socfpga but broke rockchip: > >>>>> > >>>>> https://patchwork.ozlabs.org/patch/992553/ > >>>>> > >>>>> However, the message below wasn't shown either with that patch > >>>>> applied. > >>>>> The code just runs too early to enable the UART. > >>>>> > >>>>> Do you want to keep the message (although I failed to see in which > >>>>> situation it can be printed) or do you just dislike the #ifdef thing? > >>>> > >>>> I'd like to keep the error message if possible. Is it possible ? > >>> > >>> I have *never* seen this message yet. I have failed to produce a > >>> situation where it is shown. > >> > >> I believe that. > >> > >>> This function ('socfpga_bridges_reset') is called 5 times throughout the > >>> code, but only *one* single time with 'reset=0' as argument (only with > >>> 0, the code in question is executed). And this is in SPL before > >>> initializing the console and even before the debug UART can be > >>> initialized. > >>> > >>> As I could see, the printf *is* executed on every boot (I saw the code > >>> hanging when enabling debug UART). However, when not booting from FPGA, > >>> it is just normal that the FPGA is not ready when running SPL. Why do > >>> you want an error message here anyway? > >> > >> I was under the impression this is an error message, but it might not be > >> so ? Maybe the wording is incorrect ? > > > > Now that I re-read it, "aborting" is incorrect, yes. > > > > So how should we proceed? This is an error message that can never be > > shown (like the code is now) but breaks debug UART. > > > > I'd say we can drop it altogether. It might only be interesint if (in > > the future) that code would get called from somewhere else (i.e. later, > > after console initialization). > > > > Re-reading spl_gen5.c, there are some 'debug' calls before the debug > > uart is initialized which probably would need to be removed as well, but > > that's a different story... > > How come those don't hang the system then ?
I just haven't enabled debug output in spl_gen5.c, yet. I guess they would hang the system when enabling them. While it would be easy to remove these debug statements, to be future-proof it would of course make sense to make the debug UART robust against this. But given the problems with Rockchip ns16550, we would need a dedicated debug UART for socfpga to solve this. And that would probably mean code duplication. Regards, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
