Re: [RFC PATCH v3 14/18] hw/arm/smmuv3: Support and advertise nesting

[Mostafa Saleh <smostafa@google.com>]

Hi Eric,

On Mon, May 20, 2024 at 03:16:40PM +0200, Eric Auger wrote:
> Hi Mostafa,
> 
> On 4/29/24 05:23, Mostafa Saleh wrote:
> > Everything is in place, add the last missing bits:
> > - Handle fault checking according to the actual PTW event and not the
> >   the translation stage.
> missing the "why". Can't it be moved in a separate patch?

Sure, I will split.

Thanks,
Mostafa

> > - Consolidate parsing of STE cfg and setting translation stage.
> >
> > Advertise nesting if stage requested is "nested".
> I would move the introduction of the nested option in a separate patch
> and in the associated commit msg properly document how the new option
> shall be used.
> >
> > Signed-off-by: Mostafa Saleh <smostafa@google.com>
> > ---
> >  hw/arm/smmuv3.c | 50 +++++++++++++++++++++++++++++++++----------------
> >  1 file changed, 34 insertions(+), 16 deletions(-)
> >
> > diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
> > index 96d07234fe..88f6473d33 100644
> > --- a/hw/arm/smmuv3.c
> > +++ b/hw/arm/smmuv3.c
> > @@ -34,9 +34,10 @@
> >  #include "smmuv3-internal.h"
> >  #include "smmu-internal.h"
> >  
> > -#define PTW_RECORD_FAULT(cfg)   (((cfg)->stage == SMMU_STAGE_1) ? \
> > -                                 (cfg)->record_faults : \
> > -                                 (cfg)->s2cfg.record_faults)
> > +#define PTW_RECORD_FAULT(ptw_info, cfg) (((ptw_info).stage == SMMU_STAGE_1 && \
> > +                                        (cfg)->record_faults) || \
> > +                                        ((ptw_info).stage == SMMU_STAGE_2 && \
> > +                                        (cfg)->s2cfg.record_faults))
> >  
> >  /**
> >   * smmuv3_trigger_irq - pulse @irq if enabled and update
> > @@ -260,6 +261,9 @@ static void smmuv3_init_regs(SMMUv3State *s)
> >      /* Based on sys property, the stages supported in smmu will be advertised.*/
> >      if (s->stage && !strcmp("2", s->stage)) {
> >          s->idr[0] = FIELD_DP32(s->idr[0], IDR0, S2P, 1);
> > +    } else if (s->stage && !strcmp("nested", s->stage)) {
> > +        s->idr[0] = FIELD_DP32(s->idr[0], IDR0, S1P, 1);
> > +        s->idr[0] = FIELD_DP32(s->idr[0], IDR0, S2P, 1);
> >      } else {
> >          s->idr[0] = FIELD_DP32(s->idr[0], IDR0, S1P, 1);
> >      }
> > @@ -422,8 +426,6 @@ static bool s2_pgtable_config_valid(uint8_t sl0, uint8_t t0sz, uint8_t gran)
> >  
> >  static int decode_ste_s2_cfg(SMMUTransCfg *cfg, STE *ste)
> >  {
> > -    cfg->stage = SMMU_STAGE_2;
> > -
> >      if (STE_S2AA64(ste) == 0x0) {
> >          qemu_log_mask(LOG_UNIMP,
> >                        "SMMUv3 AArch32 tables not supported\n");
> > @@ -506,6 +508,27 @@ bad_ste:
> >      return -EINVAL;
> >  }
> >  
> > +static void decode_ste_config(SMMUTransCfg *cfg, uint32_t config)
> > +{
> > +
> > +    if (STE_CFG_ABORT(config)) {
> > +        cfg->aborted = true;
> > +        return;
> > +    }
> > +    if (STE_CFG_BYPASS(config)) {
> > +        cfg->bypassed = true;
> > +        return;
> > +    }
> > +
> > +    if (STE_CFG_S1_ENABLED(config)) {
> > +        cfg->stage = SMMU_STAGE_1;
> > +    }
> > +
> > +    if (STE_CFG_S2_ENABLED(config)) {
> > +        cfg->stage |= SMMU_STAGE_2;
> > +    }
> > +}
> > +
> >  /* Returns < 0 in case of invalid STE, 0 otherwise */
> >  static int decode_ste(SMMUv3State *s, SMMUTransCfg *cfg,
> >                        STE *ste, SMMUEventInfo *event)
> > @@ -522,13 +545,9 @@ static int decode_ste(SMMUv3State *s, SMMUTransCfg *cfg,
> >  
> >      config = STE_CONFIG(ste);
> >  
> > -    if (STE_CFG_ABORT(config)) {
> > -        cfg->aborted = true;
> > -        return 0;
> > -    }
> > +    decode_ste_config(cfg, config);
> >  
> > -    if (STE_CFG_BYPASS(config)) {
> > -        cfg->bypassed = true;
> > +    if (cfg->aborted || cfg->bypassed) {
> >          return 0;
> >      }
> >  
> > @@ -701,7 +720,6 @@ static int decode_cd(SMMUv3State *s, SMMUTransCfg *cfg,
> >  
> >      /* we support only those at the moment */
> >      cfg->aa64 = true;
> > -    cfg->stage = SMMU_STAGE_1;
> >  
> >      cfg->oas = oas2bits(CD_IPS(cd));
> >      cfg->oas = MIN(oas2bits(SMMU_IDR5_OAS), cfg->oas);
> > @@ -901,7 +919,7 @@ static SMMUTranslationStatus smmuv3_do_translate(SMMUv3State *s, hwaddr addr,
> >              event->u.f_walk_eabt.addr2 = ptw_info.addr;
> >              break;
> >          case SMMU_PTW_ERR_TRANSLATION:
> > -            if (PTW_RECORD_FAULT(cfg)) {
> > +            if (PTW_RECORD_FAULT(ptw_info, cfg)) {
> >                  event->type = SMMU_EVT_F_TRANSLATION;
> >                  event->u.f_translation.addr = addr;
> >                  event->u.f_translation.addr2 = ptw_info.addr;
> > @@ -910,7 +928,7 @@ static SMMUTranslationStatus smmuv3_do_translate(SMMUv3State *s, hwaddr addr,
> >              }
> >              break;
> >          case SMMU_PTW_ERR_ADDR_SIZE:
> > -            if (PTW_RECORD_FAULT(cfg)) {
> > +            if (PTW_RECORD_FAULT(ptw_info, cfg)) {
> >                  event->type = SMMU_EVT_F_ADDR_SIZE;
> >                  event->u.f_addr_size.addr = addr;
> >                  event->u.f_addr_size.addr2 = ptw_info.addr;
> > @@ -919,7 +937,7 @@ static SMMUTranslationStatus smmuv3_do_translate(SMMUv3State *s, hwaddr addr,
> >              }
> >              break;
> >          case SMMU_PTW_ERR_ACCESS:
> > -            if (PTW_RECORD_FAULT(cfg)) {
> > +            if (PTW_RECORD_FAULT(ptw_info, cfg)) {
> >                  event->type = SMMU_EVT_F_ACCESS;
> >                  event->u.f_access.addr = addr;
> >                  event->u.f_access.addr2 = ptw_info.addr;
> > @@ -928,7 +946,7 @@ static SMMUTranslationStatus smmuv3_do_translate(SMMUv3State *s, hwaddr addr,
> >              }
> >              break;
> >          case SMMU_PTW_ERR_PERMISSION:
> > -            if (PTW_RECORD_FAULT(cfg)) {
> > +            if (PTW_RECORD_FAULT(ptw_info, cfg)) {
> >                  event->type = SMMU_EVT_F_PERMISSION;
> >                  event->u.f_permission.addr = addr;
> >                  event->u.f_permission.addr2 = ptw_info.addr;
> Thanks
> 
> Eric
>