Re: [Qemu-devel] [PATCH v2 5/7] target-arm: Remove old code and replace with new functions

[Peter Crosthwaite <peter.crosthwaite@xilinx.com>]

On Thu, Jun 26, 2014 at 3:02 PM, Alistair Francis
<alistair.francis@xilinx.com> wrote:
> Remove the old PMCCNTR code and replace it with calls to the new
> pmccntr_sync() function and the CCNT_ENABLED macro

arm_ccnt_enabled() function.

>
> Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
> ---
>
>  target-arm/helper.c |   27 ++++-----------------------
>  1 files changed, 4 insertions(+), 23 deletions(-)
>
> diff --git a/target-arm/helper.c b/target-arm/helper.c
> index 016fe47..0bd00cb 100644
> --- a/target-arm/helper.c
> +++ b/target-arm/helper.c
> @@ -609,20 +609,7 @@ void pmccntr_sync(CPUARMState *env)
>  static void pmcr_write(CPUARMState *env, const ARMCPRegInfo *ri,
>                         uint64_t value)
>  {
> -    uint64_t temp_ticks;
> -
> -    temp_ticks = muldiv64(qemu_clock_get_us(QEMU_CLOCK_VIRTUAL),
> -                          get_ticks_per_sec(), 1000000);
> -
> -    if (env->cp15.c9_pmcr & PMCRE) {
> -        /* If the counter is enabled */
> -        if (env->cp15.c9_pmcr & PMCRD) {
> -            /* Increment once every 64 processor clock cycles */
> -            env->cp15.c15_ccnt = (temp_ticks/64) - env->cp15.c15_ccnt;
> -        } else {
> -            env->cp15.c15_ccnt = temp_ticks - env->cp15.c15_ccnt;
> -        }
> -    }
> +    pmccntr_sync(env);
>
>      if (value & PMCRC) {
>          /* The counter has been reset */
> @@ -633,20 +620,14 @@ static void pmcr_write(CPUARMState *env, const ARMCPRegInfo *ri,
>      env->cp15.c9_pmcr &= ~0x39;
>      env->cp15.c9_pmcr |= (value & 0x39);
>
> -    if (env->cp15.c9_pmcr & PMCRE) {
> -        if (env->cp15.c9_pmcr & PMCRD) {
> -            /* Increment once every 64 processor clock cycles */
> -            temp_ticks /= 64;
> -        }
> -        env->cp15.c15_ccnt = temp_ticks - env->cp15.c15_ccnt;
> -    }
> +    pmccntr_sync(env);
>  }
>
>  static uint64_t pmccntr_read(CPUARMState *env, const ARMCPRegInfo *ri)
>  {
>      uint64_t total_ticks;
>
> -    if (!(env->cp15.c9_pmcr & PMCRE)) {
> +    if (!arm_ccnt_enabled(env)) {
>          /* Counter is disabled, do not change value */
>          return env->cp15.c15_ccnt;
>      }
> @@ -666,7 +647,7 @@ static void pmccntr_write(CPUARMState *env, const ARMCPRegInfo *ri,
>  {
>      uint64_t total_ticks;
>
> -    if (!(env->cp15.c9_pmcr & PMCRE)) {
> +    if (!arm_ccnt_enabled(env)) {

Is it valid to write to the running counter?

If so you can sync(), update sync() to implement easily now and drop the if.

Regards,
Peter

>          /* Counter is disabled, set the absolute value */
>          env->cp15.c15_ccnt = value;
>          return;
> --
> 1.7.1
>
>