Hi Padmarao,
On Fri, Dec 11, 2020 at 4:49 PM Padmarao Begari <padmara...@gmail.com> wrote:
>
> Hi Bin,
>
> On Thu, Dec 10, 2020 at 4:08 PM Bin Meng <bmeng...@gmail.com> wrote:
>>
>> Hi Padmarao,
>>
>> On Thu, Dec 10, 2020 at 6:33 PM Bin Meng <bmeng...@gmail.com> wrote:
>> >
>> > Hi Padmarao,
>> >
>> > On Thu, Dec 3, 2020 at 4:44 AM Padmarao Begari
>> > <padmarao.beg...@microchip.com> wrote:
>> > >
>> > > Enable 32-bit or 64-bit DMA in the macb driver based on the macb
>> > > compatible string of the device tree node.
>> > >
>> > > Signed-off-by: Padmarao Begari <padmarao.beg...@microchip.com>
>> > > Reviewed-by: Anup Patel <anup.pa...@wdc.com>
>> > > ---
>> > > drivers/net/macb.c | 131 +++++++++++++++++++++++++++++++++++++++------
>> > > drivers/net/macb.h | 6 +++
>> > > 2 files changed, 120 insertions(+), 17 deletions(-)
>> > >
>> > > diff --git a/drivers/net/macb.c b/drivers/net/macb.c
>> > > index b80a259ff7..e7c93d4747 100644
>> > > --- a/drivers/net/macb.c
>> > > +++ b/drivers/net/macb.c
>> > > @@ -83,7 +83,16 @@ struct macb_dma_desc {
>> > > u32 ctrl;
>> > > };
>> > >
>> > > -#define DMA_DESC_BYTES(n) (n * sizeof(struct macb_dma_desc))
>> > > +struct macb_dma_desc_64 {
>> > > + u32 addrh;
>> > > + u32 unused;
>> > > +};
>> > > +
>> > > +#define HW_DMA_CAP_32B 0
>> > > +#define HW_DMA_CAP_64B 1
>> > > +
>> > > +#define DMA_DESC_SIZE 16
>> > > +#define DMA_DESC_BYTES(n) ((n) * DMA_DESC_SIZE)
>> > > #define MACB_TX_DMA_DESC_SIZE (DMA_DESC_BYTES(MACB_TX_RING_SIZE))
>> > > #define MACB_RX_DMA_DESC_SIZE (DMA_DESC_BYTES(MACB_RX_RING_SIZE))
>> > > #define MACB_TX_DUMMY_DMA_DESC_SIZE (DMA_DESC_BYTES(1))
>> > > @@ -133,6 +142,7 @@ struct macb_device {
>> > > #endif
>> > > phy_interface_t phy_interface;
>> > > #endif
>> > > + unsigned short hw_dma_cap;
>> > > };
>> > >
>> > > struct macb_config {
>> > > @@ -307,6 +317,24 @@ static inline void macb_invalidate_rx_buffer(struct
>> > > macb_device *macb)
>> > >
>> > > #if defined(CONFIG_CMD_NET)
>> > >
>> > > +static struct macb_dma_desc_64 *macb_64b_desc(struct macb_dma_desc
>> > > *desc)
>> > > +{
>> > > + return (struct macb_dma_desc_64 *)((void *)desc
>> > > + + sizeof(struct macb_dma_desc));
>> > > +}
>> > > +
>> > > +static void macb_set_addr(struct macb_device *macb, struct
>> > > macb_dma_desc *desc,
>> > > + ulong addr)
>> > > +{
>> > > + struct macb_dma_desc_64 *desc_64;
>> > > +
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B) {
>> > > + desc_64 = macb_64b_desc(desc);
>> > > + desc_64->addrh = upper_32_bits(addr);
>> > > + }
>> > > + desc->addr = lower_32_bits(addr);
>> > > +}
>> > > +
>> > > static int _macb_send(struct macb_device *macb, const char *name, void
>> > > *packet,
>> > > int length)
>> > > {
>> > > @@ -325,8 +353,12 @@ static int _macb_send(struct macb_device *macb,
>> > > const char *name, void *packet,
>> > > macb->tx_head++;
>> > > }
>> > >
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B)
>> > > + tx_head = tx_head * 2;
>> > > +
>> > > macb->tx_ring[tx_head].ctrl = ctrl;
>> > > - macb->tx_ring[tx_head].addr = paddr;
>> > > + macb_set_addr(macb, &macb->tx_ring[tx_head], paddr);
>> > > +
>> > > barrier();
>> > > macb_flush_ring_desc(macb, TX);
>> > > macb_writel(macb, NCR, MACB_BIT(TE) | MACB_BIT(RE) |
>> > > MACB_BIT(TSTART));
>> > > @@ -363,19 +395,28 @@ static void reclaim_rx_buffers(struct macb_device
>> > > *macb,
>> > > unsigned int new_tail)
>> > > {
>> > > unsigned int i;
>> > > + unsigned int count;
>> > >
>> > > i = macb->rx_tail;
>> > >
>> > > macb_invalidate_ring_desc(macb, RX);
>> > > while (i > new_tail) {
>> > > - macb->rx_ring[i].addr &= ~MACB_BIT(RX_USED);
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B)
>> > > + count = i * 2;
>> > > + else
>> > > + count = i;
>> > > + macb->rx_ring[count].addr &= ~MACB_BIT(RX_USED);
>> > > i++;
>> > > if (i > MACB_RX_RING_SIZE)
>> > > i = 0;
>> > > }
>> > >
>> > > while (i < new_tail) {
>> > > - macb->rx_ring[i].addr &= ~MACB_BIT(RX_USED);
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B)
>> > > + count = i * 2;
>> > > + else
>> > > + count = i;
>> > > + macb->rx_ring[count].addr &= ~MACB_BIT(RX_USED);
>> > > i++;
>> > > }
>> > >
>> > > @@ -390,16 +431,25 @@ static int _macb_recv(struct macb_device *macb,
>> > > uchar **packetp)
>> > > void *buffer;
>> > > int length;
>> > > u32 status;
>> > > + u8 flag = false;
>> > >
>> > > macb->wrapped = false;
>> > > for (;;) {
>> > > macb_invalidate_ring_desc(macb, RX);
>> > >
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B)
>> > > + next_rx_tail = next_rx_tail * 2;
>> > > +
>> > > if (!(macb->rx_ring[next_rx_tail].addr &
>> > > MACB_BIT(RX_USED)))
>> > > return -EAGAIN;
>> > >
>> > > status = macb->rx_ring[next_rx_tail].ctrl;
>> > > if (status & MACB_BIT(RX_SOF)) {
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B) {
>> > > + next_rx_tail = next_rx_tail / 2;
>> > > + flag = true;
>> > > + }
>> > > +
>> > > if (next_rx_tail != macb->rx_tail)
>> > > reclaim_rx_buffers(macb, next_rx_tail);
>> > > macb->wrapped = false;
>> > > @@ -426,11 +476,22 @@ static int _macb_recv(struct macb_device *macb,
>> > > uchar **packetp)
>> > > *packetp = buffer;
>> > > }
>> > >
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B) {
>> > > + if (!flag)
>> > > + next_rx_tail = next_rx_tail / 2;
>> > > + }
>> > > +
>> > > if (++next_rx_tail >= MACB_RX_RING_SIZE)
>> > > next_rx_tail = 0;
>> > > macb->next_rx_tail = next_rx_tail;
>> > > return length;
>> > > } else {
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B) {
>> > > + if (!flag)
>> > > + next_rx_tail = next_rx_tail / 2;
>> > > + flag = false;
>> > > + }
>> > > +
>> > > if (++next_rx_tail >= MACB_RX_RING_SIZE) {
>> > > macb->wrapped = true;
>> > > next_rx_tail = 0;
>> > > @@ -718,6 +779,7 @@ static int gmac_init_multi_queues(struct macb_device
>> > > *macb)
>> > > {
>> > > int i, num_queues = 1;
>> > > u32 queue_mask;
>> > > + unsigned long paddr;
>> > >
>> > > /* bit 0 is never set but queue 0 always exists */
>> > > queue_mask = gem_readl(macb, DCFG6) & 0xff;
>> > > @@ -731,10 +793,18 @@ static int gmac_init_multi_queues(struct
>> > > macb_device *macb)
>> > > macb->dummy_desc->addr = 0;
>> > > flush_dcache_range(macb->dummy_desc_dma, macb->dummy_desc_dma +
>> > > ALIGN(MACB_TX_DUMMY_DMA_DESC_SIZE, PKTALIGN));
>> > > -
>> > > - for (i = 1; i < num_queues; i++)
>> > > - gem_writel_queue_TBQP(macb, macb->dummy_desc_dma, i - 1);
>> > > -
>> > > + paddr = macb->dummy_desc_dma;
>> > > +
>> > > + for (i = 1; i < num_queues; i++) {
>> > > + gem_writel_queue_TBQP(macb, lower_32_bits(paddr), i - 1);
>> > > + gem_writel_queue_RBQP(macb, lower_32_bits(paddr), i - 1);
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B) {
>> > > + gem_writel_queue_TBQPH(macb,
>> > > upper_32_bits(paddr),
>> > > + i - 1);
>> > > + gem_writel_queue_RBQPH(macb,
>> > > upper_32_bits(paddr),
>> > > + i - 1);
>> > > + }
>> > > + }
>> > > return 0;
>> > > }
>> > >
>> > > @@ -760,6 +830,9 @@ static void gmac_configure_dma(struct macb_device
>> > > *macb)
>> > > dmacfg &= ~GEM_BIT(ENDIA_DESC);
>> > >
>> > > dmacfg &= ~GEM_BIT(ADDR64);
>> > > + if (macb->hw_dma_cap & HW_DMA_CAP_64B)
>> > > + dmacfg |= GEM_BIT(ADDR64);
>>
>> Does GEM on PolarFire not support 32-bit DMA address? I believe in
>> U-Boot we can only get 32-bit address.
>>
>
> Yes, it's not work when I tested with 32-bit DMA.
Okay, then this explains why 64-bit DMA patch is needed. Is this a bug
of the GEM IP integrated in the PolarFire?
Could you please write something in the commit message to clarify?
That would be helpful. Thanks!
Regards,
Bin
