[Qemu-devel] [PATCH] target/xtensa: fix timers test

[Qemu-devel] [PATCH] target/xtensa: fix timers test

[Max Filippov]

Change frequency of the core used in tests so that clock cycle takes
exactly 64ns. Change icount power used in tests to 6, so that each
instruction takes exactly 1 clock cycle. With these changes the
assumptions of the xtensa timers test are correct and the test must
always pass.

Longer story:
  http://lists.nongnu.org/archive/html/qemu-devel/2018-03/msg04326.html

Cc: Pavel Dovgaluk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
---
 target/xtensa/core-dc232b.c | 2 +-
 tests/tcg/xtensa/Makefile   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/target/xtensa/core-dc232b.c b/target/xtensa/core-dc232b.c
index aa07018af4e7..8846336f5cfa 100644
--- a/target/xtensa/core-dc232b.c
+++ b/target/xtensa/core-dc232b.c
@@ -47,7 +47,7 @@ static XtensaConfig dc232b __attribute__((unused)) = {
         }
     },
     .isa_internal = &xtensa_modules,
-    .clock_freq_khz = 10000,
+    .clock_freq_khz = 15625,
     DEFAULT_SECTIONS
 };
 
diff --git a/tests/tcg/xtensa/Makefile b/tests/tcg/xtensa/Makefile
index 2882c431e4a9..091518c05583 100644
--- a/tests/tcg/xtensa/Makefile
+++ b/tests/tcg/xtensa/Makefile
@@ -5,7 +5,7 @@ CROSS=xtensa-$(CORE)-elf-
 
 ifndef XT
 SIM = ../../../xtensa-softmmu/qemu-system-xtensa
-SIMFLAGS = -M sim -cpu $(CORE) -nographic -semihosting -icount 7 $(EXTFLAGS) -kernel
+SIMFLAGS = -M sim -cpu $(CORE) -nographic -semihosting -icount 6 $(EXTFLAGS) -kernel
 SIMDEBUG = -s -S
 else
 SIM = xt-run
-- 
2.11.0

Re: [Qemu-devel] [PATCH] target/xtensa: fix timers test

[Philippe Mathieu-Daudé]

Hi Max,

On 03/23/2018 10:17 AM, Max Filippov wrote:
> Change frequency of the core used in tests so that clock cycle takes
> exactly 64ns. Change icount power used in tests to 6, so that each
> instruction takes exactly 1 clock cycle. With these changes the
> assumptions of the xtensa timers test are correct and the test must
> always pass.
> 
> Longer story:
>   http://lists.nongnu.org/archive/html/qemu-devel/2018-03/msg04326.html

Would be great to have it in this commit message.

> 
> Cc: Pavel Dovgaluk <Pavel.Dovgaluk@ispras.ru>
> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
> ---
>  target/xtensa/core-dc232b.c | 2 +-
>  tests/tcg/xtensa/Makefile   | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/target/xtensa/core-dc232b.c b/target/xtensa/core-dc232b.c
> index aa07018af4e7..8846336f5cfa 100644
> --- a/target/xtensa/core-dc232b.c
> +++ b/target/xtensa/core-dc232b.c
> @@ -47,7 +47,7 @@ static XtensaConfig dc232b __attribute__((unused)) = {
>          }
>      },
>      .isa_internal = &xtensa_modules,
> -    .clock_freq_khz = 10000,
> +    .clock_freq_khz = 15625,

What about using self-explicit:

       .clock_freq_khz = (NANOSECONDS_PER_SECOND / 64) / 1000;

>      DEFAULT_SECTIONS
>  };
>  
> diff --git a/tests/tcg/xtensa/Makefile b/tests/tcg/xtensa/Makefile
> index 2882c431e4a9..091518c05583 100644
> --- a/tests/tcg/xtensa/Makefile
> +++ b/tests/tcg/xtensa/Makefile
> @@ -5,7 +5,7 @@ CROSS=xtensa-$(CORE)-elf-
>  
>  ifndef XT
>  SIM = ../../../xtensa-softmmu/qemu-system-xtensa
> -SIMFLAGS = -M sim -cpu $(CORE) -nographic -semihosting -icount 7 $(EXTFLAGS) -kernel
> +SIMFLAGS = -M sim -cpu $(CORE) -nographic -semihosting -icount 6 $(EXTFLAGS) -kernel
>  SIMDEBUG = -s -S
>  else
>  SIM = xt-run
> 

Regards,

Phil.