[Sound-open-firmware] [PATCH] trace: dma: remove disable DMA trace option

[Liam Girdwood]

On Fri, 2018-03-16 at 17:15 +0800, Pan, Xiuli wrote:
> 
> On 3/16/2018 17:04, Liam Girdwood wrote:
> > On Fri, 2018-03-16 at 12:43 +0800, Keyon Jie wrote:
> > > On 2018年03月16日 12:34, Keyon Jie wrote:
> > > > 
> > > > On 2018年03月16日 11:40, Pan, Xiuli wrote:
> > > > > 
> > > > > On 3/15/2018 23:09, Liam Girdwood wrote:
> > > > > > DMA based trace is the standard default trace method. mailbox trace
> > > > > > is
> > > > > > no longer supported.
> > > > > > 
> > > > > > Signed-off-by: Liam Girdwood <liam.r.girdwood at linux.intel.com>
> > > > > > ---
> > > > > >    configure.ac        | 10 --------
> > > > > >    src/ipc/dma-copy.c  |  2 --
> > > > > >    src/ipc/intel-ipc.c |  4 ---
> > > > > >    src/lib/Makefile.am |  6 +----
> > > > > >    src/lib/trace.c     | 70
> > > > > > +----------------------------------------------------
> > > > > >    5 files changed, 2 insertions(+), 90 deletions(-)
> > > > > > 
> > > > > > diff --git a/configure.ac b/configure.ac
> > > > > > index bb4d2e9f..9b74c6a9 100644
> > > > > > --- a/configure.ac
> > > > > > +++ b/configure.ac
> > > > > > @@ -241,16 +241,6 @@ case "$with_dsp_core" in
> > > > > >    esac
> > > > > > -# dma trace support (Optional), dma trace by default
> > > > > > -AC_ARG_ENABLE([dma-trace],
> > > > > > -        AS_HELP_STRING([--disable-dma-trace], [Disabled dma trace
> > > > > > and use fallback mailbox trace]))
> > > > > > -
> > > > > > -AS_IF([test "x$enable_dma_trace" != "xno"], [
> > > > > > -    AC_DEFINE([CONFIG_DMA_TRACE], [1], [Configure DMA trace])
> > > > > > -    ])
> > > > > > -
> > > > > > -AM_CONDITIONAL(BUILD_DMA_TRACE,  test "x$enable_dma_trace" !=
> > > > > > "xno")
> > > > > > -
> > > > > >    PLATFORM_BOOT_LDR_LDSCRIPT="boot_ldr.x"
> > > > > >    AC_SUBST(PLATFORM_BOOT_LDR_LDSCRIPT)
> > > > > 
> > > > > Hi Liam,
> > > > > 
> > > > > I think we should keep this feature. We may need this feature to debug
> > > > > the dma related bugs.
> > > > > If anything goes wrong with the DMA, or we need to enable DMA on new
> > > > > platform, the DMA trace will not work and we may need fall back to
> > > > > mail box trace to get the debug info.
> > > > 
> > > > Agree to reserve the possibility for mailbox trace, we can set default
> > > > to use dma trace, which may be helpful for debugging to special cases,
> > > 
> > > sorry, I mean that the 'mailbox trace' may be helpful for ...
> > > 
> > 
> > We still have a "mailbox" trace mechanism via trace_err() calls. The error
> > mailbox is persistent and low volume so it's unlikley to overflow too. This
> > can
> > be used for enabling DMA trace on future platforms.
> 
> Thus we need some hard code modify here to allow trace value output.
> Keep this is the easiest way for us to switch between DAM trace and 
> mailbox trace.
> I hope we can keep this.
> 
No major mod/hacks needed, we currently have :-

/* move to config.h */
#define TRACE	1
#define TRACEV	0
#define TRACEE	1

We just need another macro in trace.h to duplicate regular trace in the
persistent buffer.

This also means we don't need to rerun configure.

Liam