On 18-06-21, 12:23, Bjorn Andersson wrote:
> On Fri 18 Jun 09:18 CDT 2021, Vinod Koul wrote:
>
> > GPI DMA is one of the DMA modes supported on geni, this adds support to
> > enable that mode
>
> I think you're missing an opportunity to describe what GPI DMA is.
> Perhaps something like:
>
> In GPI DMA mode the serial engine uses the DMA controller found in the
> associated wrapper to perform its transaction, add support for enabling
> this mode in the engine.
Hmm looks like I did, I will update more kernel-doc style comments to
explain more details
>
> >
> > Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
> > ---
> > drivers/soc/qcom/qcom-geni-se.c | 32 +++++++++++++++++++++++++++++++-
> > include/linux/qcom-geni-se.h | 5 +++--
> > 2 files changed, 34 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
> > index 08d645b90ed3..40a0a1f88070 100644
> > --- a/drivers/soc/qcom/qcom-geni-se.c
> > +++ b/drivers/soc/qcom/qcom-geni-se.c
> > @@ -307,6 +307,32 @@ static void geni_se_select_dma_mode(struct geni_se *se)
> > writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
> > }
> >
> > +static void geni_se_select_gpi_mode(struct geni_se *se)
> > +{
> > + unsigned int gpi_event_en;
> > + unsigned int m_irq_en;
> > + unsigned int s_irq_en;
>
> readl and writel operates on u32, so better to use that.
Yes
>
> > +
> > + geni_se_irq_clear(se);
> > + writel(0, se->base + SE_IRQ_EN);
> > +
> > + s_irq_en = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
>
> I don't mind this being _relaxed if done on purpose, but as it's the
> only one (and there's no comment) I get the feeling that it's a mistake.
Yes it is a leftover, fixed now
>
> > + s_irq_en &= ~S_CMD_DONE_EN;
> > + writel(s_irq_en, se->base + SE_GENI_S_IRQ_EN);
>
> The use of 3 different variables (gpi_event_en, m_irq_en, s_irq_en)
> forced me to really look if the three sets of operations somehow reused
> previous results.
>
> To clarify that this isn't the case I would suggest that you use a
> single variable ("val"?) instead.
Yes updated
>
> > +
> > + m_irq_en = readl(se->base + SE_GENI_M_IRQ_EN);
> > + m_irq_en &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN |
> > + M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
> > + writel(m_irq_en, se->base + SE_GENI_M_IRQ_EN);
> > +
> > + writel(GENI_DMA_MODE_EN, se->base + SE_GENI_DMA_MODE_EN);
> > +
> > + gpi_event_en = readl(se->base + SE_GSI_EVENT_EN);
> > + gpi_event_en |= (DMA_RX_EVENT_EN | DMA_TX_EVENT_EN |
> > + GENI_M_EVENT_EN | GENI_S_EVENT_EN);
> > + writel(gpi_event_en, se->base + SE_GSI_EVENT_EN);
> > +}
> > +
> > /**
> > * geni_se_select_mode() - Select the serial engine transfer mode
> > * @se: Pointer to the concerned serial engine.
> > @@ -314,7 +340,8 @@ static void geni_se_select_dma_mode(struct geni_se *se)
> > */
> > void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
> > {
> > - WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA);
> > + WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA &&
> > + mode != GENI_GPI_DMA);
>
> This line can be left unbroken.
yaay 100 chars :-) will do
>
> >
> > switch (mode) {
> > case GENI_SE_FIFO:
> > @@ -323,6 +350,9 @@ void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
> > case GENI_SE_DMA:
> > geni_se_select_dma_mode(se);
> > break;
> > + case GENI_GPI_DMA:
> > + geni_se_select_gpi_mode(se);
> > + break;
> > case GENI_SE_INVALID:
> > default:
> > break;
> > diff --git a/include/linux/qcom-geni-se.h b/include/linux/qcom-geni-se.h
> > index 5fda675c5cfe..336b682392b1 100644
> > --- a/include/linux/qcom-geni-se.h
> > +++ b/include/linux/qcom-geni-se.h
> > @@ -11,8 +11,9 @@
> > /* Transfer mode supported by GENI Serial Engines */
> > enum geni_se_xfer_mode {
> > GENI_SE_INVALID,
> > - GENI_SE_FIFO,
> > - GENI_SE_DMA,
>
> Is the order significant? Is there a reason why SE_DMA ended up last?
Nope not that I can tjing off.. I can add this as last!
--
~Vinod
