Re: [PATCH 1/4] hw/dma: Enhance error handling in loading description

[Frank Chang]

Reviewed-by: Frank Chang <frank.chang@sifive.com>

Fea.Wang <fea.wang@sifive.com> 於 2024年6月3日 週一 下午1:48寫道：
>
> Loading a description from memory may cause a bus-error. In this
> case, the DMA should stop working, set the error flag, and return
> the error value.
>
> Signed-off-by: Fea.Wang <fea.wang@sifive.com>
> ---
>  hw/dma/xilinx_axidma.c | 16 ++++++++++++++--
>  1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
> index 0ae056ed06..4b475e5484 100644
> --- a/hw/dma/xilinx_axidma.c
> +++ b/hw/dma/xilinx_axidma.c
> @@ -71,8 +71,10 @@ enum {
>  enum {
>      DMASR_HALTED = 1,
>      DMASR_IDLE  = 2,
> +    DMASR_SLVERR = 1 << 5,
>      DMASR_IOC_IRQ  = 1 << 12,
>      DMASR_DLY_IRQ  = 1 << 13,
> +    DMASR_ERR_IRQ  = 1 << 14,
>
>      DMASR_IRQ_MASK = 7 << 12
>  };
> @@ -190,17 +192,27 @@ static inline int streamid_from_addr(hwaddr addr)
>      return sid;
>  }
>
> -static void stream_desc_load(struct Stream *s, hwaddr addr)
> +static MemTxResult stream_desc_load(struct Stream *s, hwaddr addr)
>  {
>      struct SDesc *d = &s->desc;
>
> -    address_space_read(&s->dma->as, addr, MEMTXATTRS_UNSPECIFIED, d, sizeof 
> *d);
> +    MemTxResult result = address_space_read(&s->dma->as,
> +                                            addr, MEMTXATTRS_UNSPECIFIED,
> +                                            d, sizeof *d);
> +    if (result != MEMTX_OK) {
> +        s->regs[R_DMACR] &= ~DMACR_RUNSTOP;
> +        s->regs[R_DMASR] |= DMASR_HALTED;
> +        s->regs[R_DMASR] |= DMASR_SLVERR;
> +        s->regs[R_DMASR] |= DMASR_ERR_IRQ;
> +        return result;
> +    }
>
>      /* Convert from LE into host endianness.  */
>      d->buffer_address = le64_to_cpu(d->buffer_address);
>      d->nxtdesc = le64_to_cpu(d->nxtdesc);
>      d->control = le32_to_cpu(d->control);
>      d->status = le32_to_cpu(d->status);
> +    return result;
>  }
>
>  static void stream_desc_store(struct Stream *s, hwaddr addr)
> --
> 2.34.1
>
>