Re: [Qemu-devel] [PATCH arm-devs v1 03/15] xilinx_spips: Inhibit interrupts in LQSPI mode

[Peter Maydell <peter.maydell@linaro.org>]

On 3 April 2013 05:27, Peter Crosthwaite <peter.crosthwaite@xilinx.com> wrote:
> The real hardware does not produce interrupts in LQSPI mode. Inhibit
> generation of interrupts when the LQ_MODE bit is set.
>
> Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
> ---
>
>  hw/xilinx_spips.c |    7 ++++++-
>  1 files changed, 6 insertions(+), 1 deletions(-)
>
> diff --git a/hw/xilinx_spips.c b/hw/xilinx_spips.c
> index 261d948..a8691d5 100644
> --- a/hw/xilinx_spips.c
> +++ b/hw/xilinx_spips.c
> @@ -204,6 +204,9 @@ static void xilinx_spips_update_cs_lines(XilinxSPIPS *s)
>
>  static void xilinx_spips_update_ixr(XilinxSPIPS *s)
>  {
> +    if (s->regs[R_LQSPI_CFG] & LQSPI_CFG_LQ_MODE) {
> +        return;
> +    }
>      /* These are set/cleared as they occur */
>      s->regs[R_INTR_STATUS] &= (IXR_TX_FIFO_UNDERFLOW | IXR_RX_FIFO_OVERFLOW |
>                                  IXR_TX_FIFO_MODE_FAIL);
> @@ -256,7 +259,9 @@ static void xilinx_spips_flush_txfifo(XilinxSPIPS *s)
>          for (i = 0; i < num_effective_busses(s); ++i) {
>              if (!i || s->snoop_state == SNOOP_STRIPING) {
>                  if (fifo8_is_empty(&s->tx_fifo)) {
> -                    s->regs[R_INTR_STATUS] |= IXR_TX_FIFO_UNDERFLOW;
> +                    if (!(s->regs[R_LQSPI_CFG] & LQSPI_CFG_LQ_MODE)) {
> +                        s->regs[R_INTR_STATUS] |= IXR_TX_FIFO_UNDERFLOW;
> +                    }
>                      xilinx_spips_update_ixr(s);
>                      return;
>                  } else {

How about the OVERFLOW case just below here, or is that a
deliberate omission?

-- PMM