On Thu, Aug 15, 2024 at 4:30 PM Abhishek Chauhan (ABC)
<quic_abchauha@xxxxxxxxxxx> wrote:
>
>
>
> On 8/14/2024 3:18 PM, jitendra.vegiraju@xxxxxxxxxxxx wrote:
> > From: Jitendra Vegiraju <jitendra.vegiraju@xxxxxxxxxxxx>
> >
> > Add hdma configuration support in include/linux/stmmac.h file.
> > The hdma configuration includes mapping of virtual DMAs to physical DMAs.
> > Define a new data structure stmmac_hdma_cfg to provide the mapping.
> >
> > Signed-off-by: Jitendra Vegiraju <jitendra.vegiraju@xxxxxxxxxxxx>
> > ---
> > include/linux/stmmac.h | 50 ++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 50 insertions(+)
> >
> > diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
> > index 338991c08f00..1775bd2b7c14 100644
> > --- a/include/linux/stmmac.h
> > +++ b/include/linux/stmmac.h
> > @@ -89,6 +89,55 @@ struct stmmac_mdio_bus_data {
> > bool needs_reset;
> > };
> >
> > +/* DW25GMAC Hyper-DMA Overview
> > + * Hyper-DMA allows support for large number of Virtual DMA(VDMA)
> > + * channels using a smaller set of physical DMA channels(PDMA).
> > + * This is supported by the mapping of VDMAs to Traffic Class (TC)
> > + * and PDMA to TC in each traffic direction as shown below.
> > + *
> > + * VDMAs Traffic Class PDMA
> > + * +--------+ +------+ +-----------+
> > + * |VDMA0 |--------->| TC0 |-------->|PDMA0/TXQ0 |
> > + *TX +--------+ |----->+------+ +-----------+
> > + *Host=> +--------+ | +------+ +-----------+ => MAC
> > + *SW |VDMA1 |---+ | TC1 | +--->|PDMA1/TXQ1 |
> > + * +--------+ +------+ | +-----------+
> > + * +--------+ +------+----+ +-----------+
> > + * |VDMA2 |--------->| TC2 |-------->|PDMA2/TXQ1 |
> > + * +--------+ +------+ +-----------+
> > + * . . .
> > + * +--------+ +------+ +-----------+
> > + * |VDMAn-1 |--------->| TCx-1|-------->|PDMAm/TXQm |
> > + * +--------+ +------+ +-----------+
> > + *
> > + * +------+ +------+ +------+
> > + * |PDMA0 |--------->| TC0 |-------->|VDMA0 |
> > + * +------+ |----->+------+ +------+
> > + *MAC => +------+ | +------+ +------+
> > + *RXQs |PDMA1 |---+ | TC1 | +--->|VDMA1 | => Host
> > + * +------+ +------+ | +------+
> > + * . . .
> > + */
> > +
> > +#define STMMAC_DW25GMAC_MAX_NUM_TX_VDMA 128
> > +#define STMMAC_DW25GMAC_MAX_NUM_RX_VDMA 128
> > +
> > +#define STMMAC_DW25GMAC_MAX_NUM_TX_PDMA 8
> > +#define STMMAC_DW25GMAC_MAX_NUM_RX_PDMA 10
> > +
> I have a query here.
>
> Why do we need to hardcode the number of TX PDMA and RX PDMA to 8 an 10. On some platforms the number of supported TXPDMA and RXPDMA are 11 and 11 respectively ?
>
> how do we overcome this problem, do we increase the value in such case?
>
Hi Abhishek,
Agreed, we can make the mapping tables more generic.
We will replace static arrays with dynamically allocated memory by
reading the TXPDMA and RXPDMA counts from hardware.
Thanks
> > +#define STMMAC_DW25GMAC_MAX_TC 8
> > +
> > +/* Hyper-DMA mapping configuration
> > + * Traffic Class associated with each VDMA/PDMA mapping
> > + * is stored in corresponding array entry.
> > + */
> > +struct stmmac_hdma_cfg {
> > + u8 tvdma_tc[STMMAC_DW25GMAC_MAX_NUM_TX_VDMA];
> > + u8 rvdma_tc[STMMAC_DW25GMAC_MAX_NUM_RX_VDMA];
> > + u8 tpdma_tc[STMMAC_DW25GMAC_MAX_NUM_TX_PDMA];
> > + u8 rpdma_tc[STMMAC_DW25GMAC_MAX_NUM_RX_PDMA];
> > +};
> > +
> > struct stmmac_dma_cfg {
> > int pbl;
> > int txpbl;
> > @@ -101,6 +150,7 @@ struct stmmac_dma_cfg {
> > bool multi_msi_en;
> > bool dche;
> > bool atds;
> > + struct stmmac_hdma_cfg *hdma_cfg;
> > };
> >
> > #define AXI_BLEN 7
