drivers/net/xilinx_ll_temac_fifo.c

   1 /*
   2  * Xilinx xps_ll_temac ethernet driver for u-boot
   3  *
   4  * FIFO sub-controller
   5  *
   6  * Copyright (C) 2011 - 2012 Stephan Linz <linz@li-pro.net>
   7  * Copyright (C) 2008 - 2011 Michal Simek <monstr@monstr.eu>
   8  * Copyright (C) 2008 - 2011 PetaLogix
   9  *
  10  * Based on Yoshio Kashiwagi kashiwagi@co-nss.co.jp driver
  11  * Copyright (C) 2008 Nissin Systems Co.,Ltd.
  12  * March 2008 created
  13  *
  14  * CREDITS: tsec driver
  15  *
  16  * SPDX-License-Identifier:     GPL-2.0+
  17  *
  18  * [0]: http://www.xilinx.com/support/documentation
  19  *
  20  * [F]: [0]/ip_documentation/xps_ll_fifo.pdf
  21  * [S]: [0]/ip_documentation/xps_ll_temac.pdf
  22  * [A]: [0]/application_notes/xapp1041.pdf
  23  */
  24
  25 #include <config.h>
  26 #include <common.h>
  27 #include <net.h>
  28
  29 #include <asm/types.h>
  30 #include <asm/io.h>
  31
  32 #include "xilinx_ll_temac.h"
  33 #include "xilinx_ll_temac_fifo.h"
  34
  35 int ll_temac_reset_fifo(struct eth_device *dev)
  36 {
  37         struct ll_temac *ll_temac = dev->priv;
  38         struct fifo_ctrl *fifo_ctrl = (void *)ll_temac->ctrladdr;
  39
  40         out_be32(&fifo_ctrl->tdfr, LL_FIFO_TDFR_KEY);
  41         out_be32(&fifo_ctrl->rdfr, LL_FIFO_RDFR_KEY);
  42         out_be32(&fifo_ctrl->isr, ~0UL);
  43         out_be32(&fifo_ctrl->ier, 0);
  44
  45         return 0;
  46 }
  47
  48 int ll_temac_recv_fifo(struct eth_device *dev)
  49 {
  50         int i, length = 0;
  51         u32 *buf = (u32 *)net_rx_packets[0];
  52         struct ll_temac *ll_temac = dev->priv;
  53         struct fifo_ctrl *fifo_ctrl = (void *)ll_temac->ctrladdr;
  54
  55         if (in_be32(&fifo_ctrl->isr) & LL_FIFO_ISR_RC) {
  56
  57                 /* reset isr */
  58                 out_be32(&fifo_ctrl->isr, ~0UL);
  59
  60                 /*
  61                  * MAYBE here:
  62                  *   while (fifo_ctrl->isr);
  63                  */
  64
  65                 /*
  66                  * The length is written (into RLR) by the XPS LL FIFO
  67                  * when the packet is received across the RX LocalLink
  68                  * interface and the receive data FIFO had enough
  69                  * locations that all of the packet data has been saved.
  70                  * The RLR should only be read when a receive packet is
  71                  * available for processing (the receive occupancy is
  72                  * not zero). Once the RLR is read, the receive packet
  73                  * data should be read from the receive data FIFO before
  74                  * the RLR is read again.
  75                  *
  76                  * [F] page 17, Receive Length Register (RLR)
  77                  */
  78                 if (in_be32(&fifo_ctrl->rdfo) & LL_FIFO_RDFO_MASK) {
  79                         length = in_be32(&fifo_ctrl->rlf) & LL_FIFO_RLF_MASK;
  80                 } else {
  81                         printf("%s: Got error, no receive occupancy\n",
  82                                         __func__);
  83                         return -1;
  84                 }
  85
  86                 if (length > PKTSIZE_ALIGN) {
  87                         printf("%s: Got error, receive package too big (%i)\n",
  88                                         __func__, length);
  89                         ll_temac_reset_fifo(dev);
  90                         return -1;
  91                 }
  92
  93                 for (i = 0; i < length; i += 4)
  94                         *buf++ = in_be32(&fifo_ctrl->rdfd);
  95
  96                 net_process_received_packet(net_rx_packets[0], length);
  97         }
  98
  99         return 0;
 100 }
 101
 102 int ll_temac_send_fifo(struct eth_device *dev, void *packet, int length)
 103 {
 104         int i;
 105         u32 *buf = (u32 *)packet;
 106         struct ll_temac *ll_temac = dev->priv;
 107         struct fifo_ctrl *fifo_ctrl = (void *)ll_temac->ctrladdr;
 108
 109         if (length < LL_FIFO_TLF_MIN) {
 110                 printf("%s: Got error, transmit package too small (%i)\n",
 111                                 __func__, length);
 112                 return -1;
 113         }
 114
 115         if (length > LL_FIFO_TLF_MAX) {
 116                 printf("%s: Got error, transmit package too big (%i)\n",
 117                                 __func__, length);
 118                 return -1;
 119         }
 120
 121         for (i = 0; i < length; i += 4)
 122                 out_be32(&fifo_ctrl->tdfd, *buf++);
 123
 124         /*
 125          * Once the packet length is written to the TLR it is
 126          * automatically moved to the transmit data FIFO with
 127          * the packet data freeing up the TLR for another value.
 128          * The packet length must be written to the TLR after
 129          * the packet data is written to the transmit data FIFO.
 130          * It is not valid to write data for multiple packets
 131          * to the transmit data FIFO before writing the packet
 132          * length values.
 133          *
 134          * [F] page 17, Transmit Length Register (TLR)
 135          */
 136         out_be32(&fifo_ctrl->tlf, length);
 137
 138         return 0;
 139 }