Re: [Qemu-devel] [PATCH v4 22/29] target-ppc: Add POWER8's MMCR2/MMCRS SPRs

[Tom Musta <tommusta@gmail.com>]

On 6/3/2014 4:27 AM, Alexey Kardashevskiy wrote:
> This adds POWER8 specific PMU MMCR2/MMCRS SPRs.
> 
> This adds a spr_write_ureg helper for changing a hypv-privileged SPR when
> it is accessed via its user-privileged mirror. A spr_read_ureg() is
> already there. Since the new helper is only used by book3s CPUs, it is
> limited to TARGET_PPC64 to make gcc happy when QEMU is compiled for 32 bit.
> 
> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
> ---
> Changes:
> v4:
> * disabled write_ureg for user mode, privileged mode is still needed for
> recent guest kernels to boot on POWER8
> ---
>  target-ppc/cpu.h            |  3 +++
>  target-ppc/translate_init.c | 29 +++++++++++++++++++++++++++++
>  2 files changed, 32 insertions(+)
> 
> diff --git a/target-ppc/cpu.h b/target-ppc/cpu.h
> index 32fadcd..cf1ccad 100644
> --- a/target-ppc/cpu.h
> +++ b/target-ppc/cpu.h
> @@ -1480,6 +1480,7 @@ static inline int cpu_mmu_index (CPUPPCState *env)
>  #define SPR_MPC_MI_CTR        (0x300)
>  #define SPR_PERF1             (0x301)
>  #define SPR_RCPU_MI_RBA1      (0x301)
> +#define SPR_POWER_UMMCR2      (0x301)
>  #define SPR_PERF2             (0x302)
>  #define SPR_RCPU_MI_RBA2      (0x302)
>  #define SPR_MPC_MI_AP         (0x302)
> @@ -1527,6 +1528,7 @@ static inline int cpu_mmu_index (CPUPPCState *env)
>  #define SPR_MPC_MD_TW         (0x30F)
>  #define SPR_UPERF0            (0x310)
>  #define SPR_UPERF1            (0x311)
> +#define SPR_POWER_MMCR2       (0x311)
>  #define SPR_UPERF2            (0x312)
>  #define SPR_POWER_MMCRA       (0X312)
>  #define SPR_UPERF3            (0x313)
> @@ -1579,6 +1581,7 @@ static inline int cpu_mmu_index (CPUPPCState *env)
>  #define SPR_440_ITV3          (0x377)
>  #define SPR_440_CCR1          (0x378)
>  #define SPR_DCRIPR            (0x37B)
> +#define SPR_POWER_MMCRS       (0x37E)
>  #define SPR_PPR               (0x380)
>  #define SPR_750_GQR0          (0x390)
>  #define SPR_440_DNV0          (0x390)
> diff --git a/target-ppc/translate_init.c b/target-ppc/translate_init.c
> index 9b83d56..6bb0788 100644
> --- a/target-ppc/translate_init.c
> +++ b/target-ppc/translate_init.c
> @@ -175,6 +175,13 @@ static void spr_read_ureg (void *opaque, int gprn, int sprn)
>      gen_load_spr(cpu_gpr[gprn], sprn + 0x10);
>  }
>  
> +#if defined(TARGET_PPC64) && !defined(CONFIG_USER_ONLY)
> +static void spr_write_ureg(void *opaque, int sprn, int gprn)
> +{
> +    gen_store_spr(sprn + 0x10, cpu_gpr[gprn]);
> +}
> +#endif
> +
>  /* SPR common to all non-embedded PowerPC */
>  /* DECR */
>  #if !defined(CONFIG_USER_ONLY)
> @@ -7500,6 +7507,26 @@ static void gen_spr_970_pmu_user(CPUPPCState *env)
>                   0x00000000);
>  }
>  
> +static void gen_spr_power8_pmu_hypv(CPUPPCState *env)
> +{
> +    spr_register_kvm(env, SPR_POWER_MMCR2, "MMCR2",
> +                     SPR_NOACCESS, SPR_NOACCESS,
> +                     &spr_read_generic, &spr_write_generic,
> +                     KVM_REG_PPC_MMCR2, 0x00000000);
> +    spr_register_kvm(env, SPR_POWER_MMCRS, "MMCRS",
> +                     SPR_NOACCESS, SPR_NOACCESS,
> +                     &spr_read_generic, &spr_write_generic,
> +                     KVM_REG_PPC_MMCRS, 0x00000000);
> +}


Supervisor.

> +
> +static void gen_spr_power8_pmu_user(CPUPPCState *env)
> +{
> +    spr_register(env, SPR_POWER_UMMCR2, "UMMCR2",
> +                 &spr_read_ureg, SPR_NOACCESS,
> +                 &spr_read_ureg, &spr_write_ureg,
> +                 0x00000000);
> +}
> +

The write_ureg should probably also be applied to the other PMU Uxxxx SPRs, no?

>  static void gen_spr_power5p_ear(CPUPPCState *env)
>  {
>      /* External access control */
> @@ -7656,6 +7683,8 @@ static void init_proc_book3s_64(CPUPPCState *env, int version)
>      if (version >= BOOK3S_CPU_POWER8) {
>          gen_spr_power8_tce_address_control(env);
>          gen_spr_power8_fscr(env);
> +        gen_spr_power8_pmu_hypv(env);
> +        gen_spr_power8_pmu_user(env);
>      }
>  #if !defined(CONFIG_USER_ONLY)
>      switch (version) {
> 

Reviewed-by: Tom Musta <tommusta@gmail.com>