[PATCH 10/12] net: ks8851: Receive one packet per recv call

Marek Vasut
2020-03-25T18:44:59Z

Instead of reading out the entire FIFO and possibly overwriting U-Boot
memory, read out one packet per recv call, pass it to U-Boot network
stack, and repeat. It is however necessary to cache RXFC value, because
reading that one out clears it.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Eugen Hristev <eugen.hristev@microchip.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
---
drivers/net/ks8851_mll.c | 65 ++++++++++++++++++++++------------------
1 file changed, 36 insertions(+), 29 deletions(-)

diff --git a/drivers/net/ks8851_mll.c b/drivers/net/ks8851_mll.c
index d70f0a4dc2..5a566d1c66 100644
--- a/drivers/net/ks8851_mll.c
+++ b/drivers/net/ks8851_mll.c
@@ -30,6 +30,7 @@ struct ks_net {
phys_addr_t iobase;
int bus_width;
u16 sharedbus;
+ u16 rxfc;
u8 extra_byte;
};

@@ -223,33 +224,31 @@ static inline void ks_read_qmu(struct ks_net *ks, u16 *buf, u32 len)
ks_wrreg16(ks, KS_RXQCR, RXQCR_CMD_CNTL);
}

-static void ks_rcv(struct ks_net *ks, uchar **pv_data)
+static int ks_rcv(struct ks_net *ks, uchar *data)
{
- unsigned int frame_cnt;
u16 sts, len;
- int i;
-
- frame_cnt = ks_rdreg16(ks, KS_RXFCTR) >> 8;
-
- /* read all header information */
- for (i = 0; i < frame_cnt; i++) {
- /* Checking Received packet status */
- sts = ks_rdreg16(ks, KS_RXFHSR);
- /* Get packet len from hardware */
- len = ks_rdreg16(ks, KS_RXFHBCR);
-
- if ((sts & RXFSHR_RXFV) && len && (len < RX_BUF_SIZE)) {
- /* read data block including CRC 4 bytes */
- ks_read_qmu(ks, (u16 *)(*pv_data), len);
-
- /* net_rx_packets buffer size is ok (*pv_data) */
- net_process_received_packet(*pv_data, len);
- pv_data++;
- } else {
- ks_wrreg16(ks, KS_RXQCR, RXQCR_CMD_CNTL | RXQCR_RRXEF);
- printf(DRIVERNAME ": bad packet\n");
- }
+
+ if (!ks->rxfc)
+ ks->rxfc = ks_rdreg16(ks, KS_RXFCTR) >> 8;
+
+ if (!ks->rxfc)
+ return 0;
+
+ /* Checking Received packet status */
+ sts = ks_rdreg16(ks, KS_RXFHSR);
+ /* Get packet len from hardware */
+ len = ks_rdreg16(ks, KS_RXFHBCR);
+
+ if ((sts & RXFSHR_RXFV) && len && (len < RX_BUF_SIZE)) {
+ /* read data block including CRC 4 bytes */
+ ks_read_qmu(ks, (u16 *)data, len);
+ ks->rxfc--;
+ return len - 4;
}
+
+ ks_wrreg16(ks, KS_RXQCR, RXQCR_CMD_CNTL | RXQCR_RRXEF);
+ printf(DRIVERNAME ": bad packet\n");
+ return 0;
}

/*
@@ -405,6 +404,8 @@ static int ks8851_mll_init_common(struct ks_net *ks)
/* Configure the PHY, initialize the link state */
ks8851_mll_phy_configure(ks);

+ ks->rxfc = 0;
+
/* Turn on Tx + Rx */
ks8851_mll_enable(ks);

@@ -464,16 +465,17 @@ static void ks8851_mll_halt_common(struct ks_net *ks)
* needs to be enough to prevent a packet being discarded while
* we are processing the previous one.
*/
-static int ks8851_mll_recv_common(struct ks_net *ks, uchar **data)
+static int ks8851_mll_recv_common(struct ks_net *ks, uchar *data)
{
u16 status;
+ int ret = 0;

status = ks_rdreg16(ks, KS_ISR);

ks_wrreg16(ks, KS_ISR, status);

- if (status & IRQ_RXI)
- ks_rcv(ks, data);
+ if (ks->rxfc || (status & IRQ_RXI))
+ ret = ks_rcv(ks, data);

if (status & IRQ_LDI) {
u16 pmecr = ks_rdreg16(ks, KS_PMECR);
@@ -482,7 +484,7 @@ static int ks8851_mll_recv_common(struct ks_net *ks, uchar **data)
ks_wrreg16(ks, KS_PMECR, pmecr | PMECR_WKEVT_LINK);
}

- return 0;
+ return ret;
}

static void ks8851_mll_write_hwaddr_common(struct ks_net *ks, u8 enetaddr[6])
@@ -522,8 +524,13 @@ static int ks8851_mll_send(struct eth_device *dev, void *packet, int length)
static int ks8851_mll_recv(struct eth_device *dev)
{
struct ks_net *ks = container_of(dev, struct ks_net, dev);
+ int ret;
+
+ ret = ks8851_mll_recv_common(ks, net_rx_packets[0]);
+ if (ret)
+ net_process_received_packet(net_rx_packets[0], ret);

- return ks8851_mll_recv_common(ks, (uchar **)net_rx_packets);
+ return ret;
}

static int ks8851_mll_write_hwaddr(struct eth_device *dev)
--
2.25.1