On Tue, Jun 4, 2024 at 9:10 AM Fea.Wang <fea.w...@sifive.com> wrote:
> 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 failure value.
>
> When calling the loading a description function, it should be noticed
> that the function may return a failure value. Breaking the loop in this
> case is one of the possible ways to handle it.
>
> Signed-off-by: Fea.Wang <fea.w...@sifive.com>
> Reviewed-by: Frank Chang <frank.ch...@sifive.com>
>
Thanks!
Reviewed-by: Edgar E. Iglesias <edgar.igles...@amd.com>
---
> hw/dma/xilinx_axidma.c | 30 ++++++++++++++++++++++++++----
> 1 file changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/hw/dma/xilinx_axidma.c b/hw/dma/xilinx_axidma.c
> index 0ae056ed06..ad307994c2 100644
> --- a/hw/dma/xilinx_axidma.c
> +++ b/hw/dma/xilinx_axidma.c
> @@ -71,8 +71,11 @@ enum {
> enum {
> DMASR_HALTED = 1,
> DMASR_IDLE = 2,
> + DMASR_SLVERR = 1 << 5,
> + DMASR_DECERR = 1 << 6,
> DMASR_IOC_IRQ = 1 << 12,
> DMASR_DLY_IRQ = 1 << 13,
> + DMASR_ERR_IRQ = 1 << 14,
>
> DMASR_IRQ_MASK = 7 << 12
> };
> @@ -190,17 +193,32 @@ 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) {
> + if (result == MEMTX_DECODE_ERROR) {
> + s->regs[R_DMASR] |= DMASR_DECERR;
> + } else {
> + s->regs[R_DMASR] |= DMASR_SLVERR;
> + }
> +
> + s->regs[R_DMACR] &= ~DMACR_RUNSTOP;
> + s->regs[R_DMASR] |= DMASR_HALTED;
> + 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)
> @@ -279,7 +297,9 @@ static void stream_process_mem2s(struct Stream *s,
> StreamSink *tx_data_dev,
> }
>
> while (1) {
> - stream_desc_load(s, s->regs[R_CURDESC]);
> + if (MEMTX_OK != stream_desc_load(s, s->regs[R_CURDESC])) {
> + break;
> + }
>
> if (s->desc.status & SDESC_STATUS_COMPLETE) {
> s->regs[R_DMASR] |= DMASR_HALTED;
> @@ -336,7 +356,9 @@ static size_t stream_process_s2mem(struct Stream *s,
> unsigned char *buf,
> }
>
> while (len) {
> - stream_desc_load(s, s->regs[R_CURDESC]);
> + if (MEMTX_OK != stream_desc_load(s, s->regs[R_CURDESC])) {
> + break;
> + }
>
> if (s->desc.status & SDESC_STATUS_COMPLETE) {
> s->regs[R_DMASR] |= DMASR_HALTED;
> --
> 2.34.1
>
>
