drivers/net/cs8900.c

   1 /*
   2  * Cirrus Logic CS8900A Ethernet
   3  *
   4  * (C) 2003 Wolfgang Denk, wd@denx.de
   5  *     Extension to synchronize ethaddr environment variable
   6  *     against value in EEPROM
   7  *
   8  * (C) Copyright 2002
   9  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
  10  * Marius Groeger <mgroeger@sysgo.de>
  11  *
  12  * Copyright (C) 1999 Ben Williamson <benw@pobox.com>
  13  *
  14  * See file CREDITS for list of people who contributed to this
  15  * project.
  16  *
  17  * This program is loaded into SRAM in bootstrap mode, where it waits
  18  * for commands on UART1 to read and write memory, jump to code etc.
  19  * A design goal for this program is to be entirely independent of the
  20  * target board.  Anything with a CL-PS7111 or EP7211 should be able to run
  21  * this code in bootstrap mode.  All the board specifics can be handled on
  22  * the host.
  23  *
  24  * This program is free software; you can redistribute it and/or modify
  25  * it under the terms of the GNU General Public License as published by
  26  * the Free Software Foundation; either version 2 of the License, or
  27  * (at your option) any later version.
  28  *
  29  * This program is distributed in the hope that it will be useful,
  30  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  31  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  32  * GNU General Public License for more details.
  33  *
  34  * You should have received a copy of the GNU General Public License
  35  * along with this program; if not, write to the Free Software
  36  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  37  */
  38
  39 #include <common.h>
  40 #include <command.h>
  41 #include "cs8900.h"
  42 #include <net.h>
  43
  44 #undef DEBUG
  45
  46 /* packet page register access functions */
  47
  48 #ifdef CS8900_BUS32
  49 /* we don't need 16 bit initialisation on 32 bit bus */
  50 #define get_reg_init_bus(x) get_reg((x))
  51 #else
  52 static unsigned short get_reg_init_bus (int regno)
  53 {
  54         /* force 16 bit busmode */
  55         volatile unsigned char c;
  56
  57         c = CS8900_BUS16_0;
  58         c = CS8900_BUS16_1;
  59         c = CS8900_BUS16_0;
  60         c = CS8900_BUS16_1;
  61         c = CS8900_BUS16_0;
  62
  63         CS8900_PPTR = regno;
  64         return CS8900_PDATA;
  65 }
  66 #endif
  67
  68 static unsigned short get_reg (int regno)
  69 {
  70         CS8900_PPTR = regno;
  71         return CS8900_PDATA;
  72 }
  73
  74
  75 static void put_reg (int regno, unsigned short val)
  76 {
  77         CS8900_PPTR = regno;
  78         CS8900_PDATA = val;
  79 }
  80
  81 static void eth_reset (void)
  82 {
  83         int tmo;
  84         unsigned short us;
  85
  86         /* reset NIC */
  87         put_reg (PP_SelfCTL, get_reg (PP_SelfCTL) | PP_SelfCTL_Reset);
  88
  89         /* wait for 200ms */
  90         udelay (200000);
  91         /* Wait until the chip is reset */
  92
  93         tmo = get_timer (0) + 1 * CONFIG_SYS_HZ;
  94         while ((((us = get_reg_init_bus (PP_SelfSTAT)) & PP_SelfSTAT_InitD) == 0)
  95                    && tmo < get_timer (0))
  96                 /*NOP*/;
  97 }
  98
  99 static void eth_reginit (void)
 100 {
 101         /* receive only error free packets addressed to this card */
 102         put_reg (PP_RxCTL, PP_RxCTL_IA | PP_RxCTL_Broadcast | PP_RxCTL_RxOK);
 103         /* do not generate any interrupts on receive operations */
 104         put_reg (PP_RxCFG, 0);
 105         /* do not generate any interrupts on transmit operations */
 106         put_reg (PP_TxCFG, 0);
 107         /* do not generate any interrupts on buffer operations */
 108         put_reg (PP_BufCFG, 0);
 109         /* enable transmitter/receiver mode */
 110         put_reg (PP_LineCTL, PP_LineCTL_Rx | PP_LineCTL_Tx);
 111 }
 112
 113 void cs8900_get_enetaddr (void)
 114 {
 115         int i;
 116         uchar enetaddr[6];
 117
 118         /* if the env is setup, then bail */
 119         if (eth_getenv_enetaddr("ethaddr", enetaddr))
 120                 return;
 121
 122         /* verify chip id */
 123         if (get_reg_init_bus (PP_ChipID) != 0x630e)
 124                 return;
 125         eth_reset ();
 126         if ((get_reg (PP_SelfSTAT) & (PP_SelfSTAT_EEPROM | PP_SelfSTAT_EEPROM_OK)) ==
 127                         (PP_SelfSTAT_EEPROM | PP_SelfSTAT_EEPROM_OK)) {
 128
 129                 /* Load the MAC from EEPROM */
 130                 for (i = 0; i < 6 / 2; i++) {
 131                         unsigned int Addr;
 132
 133                         Addr = get_reg (PP_IA + i * 2);
 134                         enetaddr[i * 2] = Addr & 0xFF;
 135                         enetaddr[i * 2 + 1] = Addr >> 8;
 136                 }
 137
 138                 eth_setenv_enetaddr("ethaddr", enetaddr);
 139                 debug("### Set environment from HW MAC addr = \"%pM\"\n", enetaddr);
 140         }
 141 }
 142
 143 void eth_halt (void)
 144 {
 145         /* disable transmitter/receiver mode */
 146         put_reg (PP_LineCTL, 0);
 147
 148         /* "shutdown" to show ChipID or kernel wouldn't find he cs8900 ... */
 149         get_reg_init_bus (PP_ChipID);
 150 }
 151
 152 int eth_init (bd_t * bd)
 153 {
 154         uchar enetaddr[6];
 155
 156         /* verify chip id */
 157         if (get_reg_init_bus (PP_ChipID) != 0x630e) {
 158                 printf ("CS8900 Ethernet chip not found?!\n");
 159                 return 0;
 160         }
 161
 162         eth_reset ();
 163         /* set the ethernet address */
 164         eth_getenv_enetaddr("ethaddr", enetaddr);
 165         put_reg (PP_IA + 0, enetaddr[0] | (enetaddr[1] << 8));
 166         put_reg (PP_IA + 2, enetaddr[2] | (enetaddr[3] << 8));
 167         put_reg (PP_IA + 4, enetaddr[4] | (enetaddr[5] << 8));
 168
 169         eth_reginit ();
 170         return 0;
 171 }
 172
 173 /* Get a data block via Ethernet */
 174 int eth_rx (void)
 175 {
 176         int i;
 177         unsigned short rxlen;
 178         unsigned short *addr;
 179         unsigned short status;
 180
 181         status = get_reg (PP_RER);
 182
 183         if ((status & PP_RER_RxOK) == 0)
 184                 return 0;
 185
 186         status = CS8900_RTDATA;         /* stat */
 187         rxlen = CS8900_RTDATA;          /* len */
 188
 189 #ifdef DEBUG
 190         if (rxlen > PKTSIZE_ALIGN + PKTALIGN)
 191                 printf ("packet too big!\n");
 192 #endif
 193         for (addr = (unsigned short *) NetRxPackets[0], i = rxlen >> 1; i > 0;
 194                  i--)
 195                 *addr++ = CS8900_RTDATA;
 196         if (rxlen & 1)
 197                 *addr++ = CS8900_RTDATA;
 198
 199         /* Pass the packet up to the protocol layers. */
 200         NetReceive (NetRxPackets[0], rxlen);
 201
 202         return rxlen;
 203 }
 204
 205 /* Send a data block via Ethernet. */
 206 int eth_send (volatile void *packet, int length)
 207 {
 208         volatile unsigned short *addr;
 209         int tmo;
 210         unsigned short s;
 211
 212 retry:
 213         /* initiate a transmit sequence */
 214         CS8900_TxCMD = PP_TxCmd_TxStart_Full;
 215         CS8900_TxLEN = length;
 216
 217         /* Test to see if the chip has allocated memory for the packet */
 218         if ((get_reg (PP_BusSTAT) & PP_BusSTAT_TxRDY) == 0) {
 219                 /* Oops... this should not happen! */
 220 #ifdef DEBUG
 221                 printf ("cs: unable to send packet; retrying...\n");
 222 #endif
 223                 for (tmo = get_timer (0) + 5 * CONFIG_SYS_HZ; get_timer (0) < tmo;)
 224                         /*NOP*/;
 225                 eth_reset ();
 226                 eth_reginit ();
 227                 goto retry;
 228         }
 229
 230         /* Write the contents of the packet */
 231         /* assume even number of bytes */
 232         for (addr = packet; length > 0; length -= 2)
 233                 CS8900_RTDATA = *addr++;
 234
 235         /* wait for transfer to succeed */
 236         tmo = get_timer (0) + 5 * CONFIG_SYS_HZ;
 237         while ((s = get_reg (PP_TER) & ~0x1F) == 0) {
 238                 if (get_timer (0) >= tmo)
 239                         break;
 240         }
 241
 242         /* nothing */ ;
 243         if ((s & (PP_TER_CRS | PP_TER_TxOK)) != PP_TER_TxOK) {
 244 #ifdef DEBUG
 245                 printf ("\ntransmission error %#x\n", s);
 246 #endif
 247         }
 248
 249         return 0;
 250 }
 251
 252 static void cs8900_e2prom_ready(void)
 253 {
 254         while (get_reg(PP_SelfSTAT) & SI_BUSY)
 255                 ;
 256 }
 257
 258 /***********************************************************/
 259 /* read a 16-bit word out of the EEPROM                    */
 260 /***********************************************************/
 261
 262 int cs8900_e2prom_read(unsigned char addr, unsigned short *value)
 263 {
 264         cs8900_e2prom_ready();
 265         put_reg(PP_EECMD, EEPROM_READ_CMD | addr);
 266         cs8900_e2prom_ready();
 267         *value = get_reg(PP_EEData);
 268
 269         return 0;
 270 }
 271
 272
 273 /***********************************************************/
 274 /* write a 16-bit word into the EEPROM                     */
 275 /***********************************************************/
 276
 277 int cs8900_e2prom_write(unsigned char addr, unsigned short value)
 278 {
 279         cs8900_e2prom_ready();
 280         put_reg(PP_EECMD, EEPROM_WRITE_EN);
 281         cs8900_e2prom_ready();
 282         put_reg(PP_EEData, value);
 283         put_reg(PP_EECMD, EEPROM_WRITE_CMD | addr);
 284         cs8900_e2prom_ready();
 285         put_reg(PP_EECMD, EEPROM_WRITE_DIS);
 286         cs8900_e2prom_ready();
 287
 288         return 0;
 289 }