arch/ppc/boot/simple/m8260_tty.c

   1 /* Minimal serial functions needed to send messages out the serial
   2  * port on SMC1.
   3  */
   4 #include <linux/types.h>
   5 #include <asm/mpc8260.h>
   6 #include <asm/cpm2.h>
   7 #include <asm/immap_cpm2.h>
   8
   9 uint    no_print;
  10 extern char     *params[];
  11 extern int      nparams;
  12 static          u_char  cons_hold[128], *sgptr;
  13 static          int     cons_hold_cnt;
  14
  15 /* If defined, enables serial console.  The value (1 through 4)
  16  * should designate which SCC is used, but this isn't complete.  Only
  17  * SCC1 is known to work at this time.
  18  * We're only linked if SERIAL_CPM_CONSOLE=y, so we only need to test
  19  * SERIAL_CPM_SCC1.
  20  */
  21 #ifdef CONFIG_SERIAL_CPM_SCC1
  22 #define SCC_CONSOLE 1
  23 #endif
  24
  25 unsigned long
  26 serial_init(int ignored, bd_t *bd)
  27 {
  28 #ifdef SCC_CONSOLE
  29         volatile scc_t          *sccp;
  30         volatile scc_uart_t     *sup;
  31 #else
  32         volatile smc_t          *sp;
  33         volatile smc_uart_t     *up;
  34 #endif
  35         volatile cbd_t  *tbdf, *rbdf;
  36         volatile cpm2_map_t     *ip;
  37         volatile iop_cpm2_t     *io;
  38         volatile cpm_cpm2_t     *cp;
  39         uint    dpaddr, memaddr;
  40
  41         ip = (cpm2_map_t *)CPM_MAP_ADDR;
  42         cp = &ip->im_cpm;
  43         io = &ip->im_ioport;
  44
  45         /* Perform a reset.
  46         */
  47         cp->cp_cpcr = (CPM_CR_RST | CPM_CR_FLG);
  48
  49         /* Wait for it.
  50         */
  51         while (cp->cp_cpcr & CPM_CR_FLG);
  52
  53 #ifdef CONFIG_ADS8260
  54         /* Enable the RS-232 transceivers.
  55         */
  56         *(volatile uint *)(BCSR_ADDR + 4) &=
  57                                         ~(BCSR1_RS232_EN1 | BCSR1_RS232_EN2);
  58 #endif
  59
  60 #ifdef SCC_CONSOLE
  61         sccp = (scc_t *)&(ip->im_scc[SCC_CONSOLE-1]);
  62         sup = (scc_uart_t *)&ip->im_dprambase[PROFF_SCC1 + ((SCC_CONSOLE-1) << 8)];
  63         sccp->scc_sccm &= ~(UART_SCCM_TX | UART_SCCM_RX);
  64         sccp->scc_gsmrl &= ~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);
  65
  66         /* Use Port D for SCC1 instead of other functions.
  67         */
  68         io->iop_ppard |= 0x00000003;
  69         io->iop_psord &= ~0x00000001;   /* Rx */
  70         io->iop_psord |= 0x00000002;    /* Tx */
  71         io->iop_pdird &= ~0x00000001;   /* Rx */
  72         io->iop_pdird |= 0x00000002;    /* Tx */
  73
  74 #else
  75         sp = (smc_t*)&(ip->im_smc[0]);
  76         *(ushort *)(&ip->im_dprambase[PROFF_SMC1_BASE]) = PROFF_SMC1;
  77         up = (smc_uart_t *)&ip->im_dprambase[PROFF_SMC1];
  78
  79         /* Disable transmitter/receiver.
  80         */
  81         sp->smc_smcmr &= ~(SMCMR_REN | SMCMR_TEN);
  82
  83         /* Use Port D for SMC1 instead of other functions.
  84         */
  85         io->iop_ppard |= 0x00c00000;
  86         io->iop_pdird |= 0x00400000;
  87         io->iop_pdird &= ~0x00800000;
  88         io->iop_psord &= ~0x00c00000;
  89 #endif
  90
  91         /* Allocate space for two buffer descriptors in the DP ram.
  92          * For now, this address seems OK, but it may have to
  93          * change with newer versions of the firmware.
  94          */
  95         dpaddr = 0x0800;
  96
  97         /* Grab a few bytes from the top of memory.
  98          */
  99         memaddr = (bd->bi_memsize - 256) & ~15;
 100
 101         /* Set the physical address of the host memory buffers in
 102          * the buffer descriptors.
 103          */
 104         rbdf = (cbd_t *)&ip->im_dprambase[dpaddr];
 105         rbdf->cbd_bufaddr = memaddr;
 106         rbdf->cbd_sc = 0;
 107         tbdf = rbdf + 1;
 108         tbdf->cbd_bufaddr = memaddr+128;
 109         tbdf->cbd_sc = 0;
 110
 111         /* Set up the uart parameters in the parameter ram.
 112         */
 113 #ifdef SCC_CONSOLE
 114         sup->scc_genscc.scc_rbase = dpaddr;
 115         sup->scc_genscc.scc_tbase = dpaddr + sizeof(cbd_t);
 116
 117         /* Set up the uart parameters in the
 118          * parameter ram.
 119          */
 120         sup->scc_genscc.scc_rfcr = CPMFCR_GBL | CPMFCR_EB;
 121         sup->scc_genscc.scc_tfcr = CPMFCR_GBL | CPMFCR_EB;
 122
 123         sup->scc_genscc.scc_mrblr = 128;
 124         sup->scc_maxidl = 8;
 125         sup->scc_brkcr = 1;
 126         sup->scc_parec = 0;
 127         sup->scc_frmec = 0;
 128         sup->scc_nosec = 0;
 129         sup->scc_brkec = 0;
 130         sup->scc_uaddr1 = 0;
 131         sup->scc_uaddr2 = 0;
 132         sup->scc_toseq = 0;
 133         sup->scc_char1 = 0x8000;
 134         sup->scc_char2 = 0x8000;
 135         sup->scc_char3 = 0x8000;
 136         sup->scc_char4 = 0x8000;
 137         sup->scc_char5 = 0x8000;
 138         sup->scc_char6 = 0x8000;
 139         sup->scc_char7 = 0x8000;
 140         sup->scc_char8 = 0x8000;
 141         sup->scc_rccm = 0xc0ff;
 142
 143         /* Send the CPM an initialize command.
 144         */
 145         cp->cp_cpcr = mk_cr_cmd(CPM_CR_SCC1_PAGE, CPM_CR_SCC1_SBLOCK, 0,
 146                         CPM_CR_INIT_TRX) | CPM_CR_FLG;
 147         while (cp->cp_cpcr & CPM_CR_FLG);
 148
 149         /* Set UART mode, 8 bit, no parity, one stop.
 150          * Enable receive and transmit.
 151          */
 152         sccp->scc_gsmrh = 0;
 153         sccp->scc_gsmrl =
 154                 (SCC_GSMRL_MODE_UART | SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16);
 155
 156         /* Disable all interrupts and clear all pending
 157          * events.
 158          */
 159         sccp->scc_sccm = 0;
 160         sccp->scc_scce = 0xffff;
 161         sccp->scc_dsr = 0x7e7e;
 162         sccp->scc_psmr = 0x3000;
 163
 164         /* Wire BRG1 to SCC1.  The console driver will take care of
 165          * others.
 166          */
 167         ip->im_cpmux.cmx_scr = 0;
 168 #else
 169         up->smc_rbase = dpaddr;
 170         up->smc_tbase = dpaddr+sizeof(cbd_t);
 171         up->smc_rfcr = CPMFCR_EB;
 172         up->smc_tfcr = CPMFCR_EB;
 173         up->smc_brklen = 0;
 174         up->smc_brkec = 0;
 175         up->smc_brkcr = 0;
 176         up->smc_mrblr = 128;
 177         up->smc_maxidl = 8;
 178
 179         /* Set UART mode, 8 bit, no parity, one stop.
 180          * Enable receive and transmit.
 181          */
 182         sp->smc_smcmr = smcr_mk_clen(9) |  SMCMR_SM_UART;
 183
 184         /* Mask all interrupts and remove anything pending.
 185         */
 186         sp->smc_smcm = 0;
 187         sp->smc_smce = 0xff;
 188
 189         /* Set up the baud rate generator.
 190          */
 191         ip->im_cpmux.cmx_smr = 0;
 192 #endif
 193
 194         /* The baud rate divisor needs to be coordinated with clk_8260().
 195         */
 196         ip->im_brgc1 =
 197                 (((bd->bi_brgfreq/16) / bd->bi_baudrate) << 1) |
 198                                                                 CPM_BRG_EN;
 199
 200         /* Make the first buffer the only buffer.
 201         */
 202         tbdf->cbd_sc |= BD_SC_WRAP;
 203         rbdf->cbd_sc |= BD_SC_EMPTY | BD_SC_WRAP;
 204
 205         /* Initialize Tx/Rx parameters.
 206         */
 207 #ifdef SCC_CONSOLE
 208         sccp->scc_gsmrl |= (SCC_GSMRL_ENR | SCC_GSMRL_ENT);
 209 #else
 210         cp->cp_cpcr = mk_cr_cmd(CPM_CR_SMC1_PAGE, CPM_CR_SMC1_SBLOCK, 0, CPM_CR_INIT_TRX) | CPM_CR_FLG;
 211         while (cp->cp_cpcr & CPM_CR_FLG);
 212
 213         /* Enable transmitter/receiver.
 214         */
 215         sp->smc_smcmr |= SMCMR_REN | SMCMR_TEN;
 216 #endif
 217
 218         /* This is ignored.
 219         */
 220         return 0;
 221 }
 222
 223 int
 224 serial_readbuf(u_char *cbuf)
 225 {
 226         volatile cbd_t          *rbdf;
 227         volatile char           *buf;
 228 #ifdef SCC_CONSOLE
 229         volatile scc_uart_t     *sup;
 230 #else
 231         volatile smc_uart_t     *up;
 232 #endif
 233         volatile cpm2_map_t     *ip;
 234         int     i, nc;
 235
 236         ip = (cpm2_map_t *)CPM_MAP_ADDR;
 237
 238 #ifdef SCC_CONSOLE
 239         sup = (scc_uart_t *)&ip->im_dprambase[PROFF_SCC1 + ((SCC_CONSOLE-1) << 8)];
 240         rbdf = (cbd_t *)&ip->im_dprambase[sup->scc_genscc.scc_rbase];
 241 #else
 242         up = (smc_uart_t *)&(ip->im_dprambase[PROFF_SMC1]);
 243         rbdf = (cbd_t *)&ip->im_dprambase[up->smc_rbase];
 244 #endif
 245
 246         /* Wait for character to show up.
 247         */
 248         buf = (char *)rbdf->cbd_bufaddr;
 249         while (rbdf->cbd_sc & BD_SC_EMPTY);
 250         nc = rbdf->cbd_datlen;
 251         for (i=0; i<nc; i++)
 252                 *cbuf++ = *buf++;
 253         rbdf->cbd_sc |= BD_SC_EMPTY;
 254
 255         return(nc);
 256 }
 257
 258 void
 259 serial_putc(void *ignored, const char c)
 260 {
 261         volatile cbd_t          *tbdf;
 262         volatile char           *buf;
 263 #ifdef SCC_CONSOLE
 264         volatile scc_uart_t     *sup;
 265 #else
 266         volatile smc_uart_t     *up;
 267 #endif
 268         volatile cpm2_map_t     *ip;
 269
 270         ip = (cpm2_map_t *)CPM_MAP_ADDR;
 271 #ifdef SCC_CONSOLE
 272         sup = (scc_uart_t *)&ip->im_dprambase[PROFF_SCC1 + ((SCC_CONSOLE-1) << 8)];
 273         tbdf = (cbd_t *)&ip->im_dprambase[sup->scc_genscc.scc_tbase];
 274 #else
 275         up = (smc_uart_t *)&(ip->im_dprambase[PROFF_SMC1]);
 276         tbdf = (cbd_t *)&ip->im_dprambase[up->smc_tbase];
 277 #endif
 278
 279         /* Wait for last character to go.
 280         */
 281         buf = (char *)tbdf->cbd_bufaddr;
 282         while (tbdf->cbd_sc & BD_SC_READY);
 283
 284         *buf = c;
 285         tbdf->cbd_datlen = 1;
 286         tbdf->cbd_sc |= BD_SC_READY;
 287 }
 288
 289 char
 290 serial_getc(void *ignored)
 291 {
 292         char    c;
 293
 294         if (cons_hold_cnt <= 0) {
 295                 cons_hold_cnt = serial_readbuf(cons_hold);
 296                 sgptr = cons_hold;
 297         }
 298         c = *sgptr++;
 299         cons_hold_cnt--;
 300
 301         return(c);
 302 }
 303
 304 int
 305 serial_tstc(void *ignored)
 306 {
 307         volatile cbd_t          *rbdf;
 308 #ifdef SCC_CONSOLE
 309         volatile scc_uart_t     *sup;
 310 #else
 311         volatile smc_uart_t     *up;
 312 #endif
 313         volatile cpm2_map_t     *ip;
 314
 315         ip = (cpm2_map_t *)CPM_MAP_ADDR;
 316 #ifdef SCC_CONSOLE
 317         sup = (scc_uart_t *)&ip->im_dprambase[PROFF_SCC1 + ((SCC_CONSOLE-1) << 8)];
 318         rbdf = (cbd_t *)&ip->im_dprambase[sup->scc_genscc.scc_rbase];
 319 #else
 320         up = (smc_uart_t *)&(ip->im_dprambase[PROFF_SMC1]);
 321         rbdf = (cbd_t *)&ip->im_dprambase[up->smc_rbase];
 322 #endif
 323
 324         return(!(rbdf->cbd_sc & BD_SC_EMPTY));
 325 }