ref: a968f9c8d403cb77599899309f1373a1b746d4bc
dir: /os/mpc/etherscc.c/
/*
* SCCn ethernet
*/
#include "u.h"
#include "lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "../port/error.h"
#include "../port/netif.h"
#include "etherif.h"
enum {
Nrdre = 16, /* receive descriptor ring entries */
Ntdre = 16, /* transmit descriptor ring entries */
Rbsize = ETHERMAXTU+4, /* ring buffer size (+4 for CRC) */
Bufsize = (Rbsize+7)&~7, /* aligned */
};
enum {
/* ether-specific Rx BD bits */
RxMiss= 1<<8,
RxeLG= 1<<5,
RxeNO= 1<<4,
RxeSH= 1<<3,
RxeCR= 1<<2,
RxeOV= 1<<1,
RxeCL= 1<<0,
RxError= (RxeLG|RxeNO|RxeSH|RxeCR|RxeOV|RxeCL), /* various error flags */
/* ether-specific Tx BD bits */
TxPad= 1<<14, /* pad short frames */
TxTC= 1<<10, /* transmit CRC */
TxeDEF= 1<<9,
TxeHB= 1<<8,
TxeLC= 1<<7,
TxeRL= 1<<6,
TxeUN= 1<<1,
TxeCSL= 1<<0,
/* scce */
RXB= 1<<0,
TXB= 1<<1,
BSY= 1<<2,
RXF= 1<<3,
TXE= 1<<4,
/* psmr */
PRO= 1<<9, /* promiscuous mode */
/* gsmrl */
ENR= 1<<5,
ENT= 1<<4,
/* port A */
RXD1= SIBIT(15),
TXD1= SIBIT(14),
/* port B */
RTS1= IBIT(19),
/* port C */
CTS1= SIBIT(11),
CD1= SIBIT(10),
};
typedef struct Etherparam Etherparam;
struct Etherparam {
SCCparam;
ulong c_pres; /* preset CRC */
ulong c_mask; /* constant mask for CRC */
ulong crcec; /* CRC error counter */
ulong alec; /* alighnment error counter */
ulong disfc; /* discard frame counter */
ushort pads; /* short frame PAD characters */
ushort ret_lim; /* retry limit threshold */
ushort ret_cnt; /* retry limit counter */
ushort mflr; /* maximum frame length reg */
ushort minflr; /* minimum frame length reg */
ushort maxd1; /* maximum DMA1 length reg */
ushort maxd2; /* maximum DMA2 length reg */
ushort maxd; /* rx max DMA */
ushort dma_cnt; /* rx dma counter */
ushort max_b; /* max bd byte count */
ushort gaddr[4]; /* group address filter */
ulong tbuf0_data0; /* save area 0 - current frm */
ulong tbuf0_data1; /* save area 1 - current frm */
ulong tbuf0_rba0;
ulong tbuf0_crc;
ushort tbuf0_bcnt;
ushort paddr[3]; /* physical address LSB to MSB increasing */
ushort p_per; /* persistence */
ushort rfbd_ptr; /* rx first bd pointer */
ushort tfbd_ptr; /* tx first bd pointer */
ushort tlbd_ptr; /* tx last bd pointer */
ulong tbuf1_data0; /* save area 0 - next frame */
ulong tbuf1_data1; /* save area 1 - next frame */
ulong tbuf1_rba0;
ulong tbuf1_crc;
ushort tbuf1_bcnt;
ushort tx_len; /* tx frame length counter */
ushort iaddr[4]; /* individual address filter*/
ushort boff_cnt; /* back-off counter */
ushort taddr[3]; /* temp address */
};
typedef struct {
Lock;
int port;
int init;
int active;
SCC* scc;
CPMdev* cpm;
Ring;
ulong interrupts; /* statistics */
ulong deferred;
ulong heartbeat;
ulong latecoll;
ulong retrylim;
ulong underrun;
ulong overrun;
ulong carrierlost;
ulong retrycount;
} Ctlr;
static int sccid[] = {-1, CPscc1, CPscc2, CPscc3, CPscc4};
static void
attach(Ether *ether)
{
Ctlr *ctlr;
ctlr = ether->ctlr;
ctlr->active = 1;
ctlr->scc->gsmrl |= ENR|ENT;
eieio();
}
static void
closed(Ether *ether)
{
Ctlr *ctlr;
ctlr = ether->ctlr;
if(ctlr->active){
sccxstop(ctlr->cpm);
ilock(ctlr);
ctlr->active = 0;
iunlock(ctlr);
}
}
static void
promiscuous(void* arg, int on)
{
Ether *ether;
Ctlr *ctlr;
ether = (Ether*)arg;
ctlr = ether->ctlr;
ilock(ctlr);
if(on || ether->nmaddr)
ctlr->scc->psmr |= PRO;
else
ctlr->scc->psmr &= ~PRO;
iunlock(ctlr);
}
static void
multicast(void* arg, uchar *addr, int on)
{
Ether *ether;
Ctlr *ctlr;
USED(addr, on); /* if on, could SetGroupAddress; if !on, it's hard */
ether = (Ether*)arg;
ctlr = ether->ctlr;
ilock(ctlr);
if(ether->prom || ether->nmaddr)
ctlr->scc->psmr |= PRO;
else
ctlr->scc->psmr &= ~PRO;
iunlock(ctlr);
}
static void
txstart(Ether *ether)
{
int len;
Ctlr *ctlr;
Block *b;
BD *dre;
ctlr = ether->ctlr;
while(ctlr->ntq < Ntdre-1){
b = qget(ether->oq);
if(b == 0)
break;
dre = &ctlr->tdr[ctlr->tdrh];
if(dre->status & BDReady)
panic("ether: txstart");
/*
* Give ownership of the descriptor to the chip, increment the
* software ring descriptor pointer and tell the chip to poll.
*/
len = BLEN(b);
dcflush(b->rp, len);
if(ctlr->txb[ctlr->tdrh] != nil)
panic("scc/ether: txstart");
ctlr->txb[ctlr->tdrh] = b;
if((ulong)b->rp&1)
panic("scc/ether: txstart align"); /* TO DO: ensure alignment */
dre->addr = PADDR(b->rp);
dre->length = len;
eieio();
dre->status = (dre->status & BDWrap) | BDReady|TxPad|BDInt|BDLast|TxTC;
eieio();
ctlr->scc->todr = 1<<15; /* transmit now */
eieio();
ctlr->ntq++;
ctlr->tdrh = NEXT(ctlr->tdrh, Ntdre);
}
}
static void
transmit(Ether* ether)
{
Ctlr *ctlr;
ctlr = ether->ctlr;
ilock(ctlr);
txstart(ether);
iunlock(ctlr);
}
static void
interrupt(Ureg*, void *arg)
{
Ether *ether;
int len, events, status;
Ctlr *ctlr;
BD *dre;
Block *b;
ether = arg;
ctlr = ether->ctlr;
if(!ctlr->active)
return; /* not ours */
/*
* Acknowledge all interrupts and whine about those that shouldn't
* happen.
*/
events = ctlr->scc->scce;
eieio();
ctlr->scc->scce = events;
eieio();
ctlr->interrupts++;
if(events & (TXE|BSY|RXB)){
if(events & RXB)
ctlr->overrun++;
if(events & TXE)
ether->oerrs++;
if(0 || events & TXE)
print("ETHER.SCC#%d: scce = 0x%uX\n", ether->ctlrno, events);
}
/*
* Receiver interrupt: run round the descriptor ring logging
* errors and passing valid receive data up to the higher levels
* until we encounter a descriptor still owned by the chip.
*/
if(events & (RXF|RXB) || 1){
dre = &ctlr->rdr[ctlr->rdrx];
while(((status = dre->status) & BDEmpty) == 0){
if(status & RxError || (status & (BDFirst|BDLast)) != (BDFirst|BDLast)){
if(status & (RxeLG|RxeSH))
ether->buffs++;
if(status & RxeNO)
ether->frames++;
if(status & RxeCR)
ether->crcs++;
if(status & RxeOV)
ether->overflows++;
//print("eth rx: %ux\n", status);
}
else{
/*
* We have a packet. Read it in.
*/
len = dre->length-4;
if((b = iallocb(len)) != 0){
dcinval(KADDR(dre->addr), len);
memmove(b->wp, KADDR(dre->addr), len);
b->wp += len;
etheriq(ether, b, 1);
}else
ether->soverflows++;
}
/*
* Finished with this descriptor, reinitialise it,
* give it back to the chip, then on to the next...
*/
dre->length = 0;
dre->status = (status & BDWrap) | BDEmpty | BDInt;
eieio();
ctlr->rdrx = NEXT(ctlr->rdrx, Nrdre);
dre = &ctlr->rdr[ctlr->rdrx];
}
}
/*
* Transmitter interrupt: handle anything queued for a free descriptor.
*/
if(events & TXB){
lock(ctlr);
while(ctlr->ntq){
dre = &ctlr->tdr[ctlr->tdri];
status = dre->status;
if(status & BDReady)
break;
if(status & TxeDEF)
ctlr->deferred++;
if(status & TxeHB)
ctlr->heartbeat++;
if(status & TxeLC)
ctlr->latecoll++;
if(status & TxeRL)
ctlr->retrylim++;
if(status & TxeUN)
ctlr->underrun++;
if(status & TxeCSL)
ctlr->carrierlost++;
ctlr->retrycount += (status>>2)&0xF;
b = ctlr->txb[ctlr->tdri];
if(b == nil)
panic("scce/interrupt: bufp");
ctlr->txb[ctlr->tdri] = nil;
freeb(b);
ctlr->ntq--;
ctlr->tdri = NEXT(ctlr->tdri, Ntdre);
}
txstart(ether);
unlock(ctlr);
}
if(events & TXE)
cpmop(ctlr->cpm, RestartTx, 0);
}
static long
ifstat(Ether* ether, void* a, long n, ulong offset)
{
char *p;
int len;
Ctlr *ctlr;
if(n == 0)
return 0;
ctlr = ether->ctlr;
p = malloc(READSTR);
len = snprint(p, READSTR, "interrupts: %lud\n", ctlr->interrupts);
len += snprint(p+len, READSTR-len, "carrierlost: %lud\n", ctlr->carrierlost);
len += snprint(p+len, READSTR-len, "heartbeat: %lud\n", ctlr->heartbeat);
len += snprint(p+len, READSTR-len, "retrylimit: %lud\n", ctlr->retrylim);
len += snprint(p+len, READSTR-len, "retrycount: %lud\n", ctlr->retrycount);
len += snprint(p+len, READSTR-len, "latecollisions: %lud\n", ctlr->latecoll);
len += snprint(p+len, READSTR-len, "rxoverruns: %lud\n", ctlr->overrun);
len += snprint(p+len, READSTR-len, "txunderruns: %lud\n", ctlr->underrun);
snprint(p+len, READSTR-len, "framesdeferred: %lud\n", ctlr->deferred);
n = readstr(offset, a, n, p);
free(p);
return n;
}
/*
* This follows the MPC823 user guide: section16.9.23.7's initialisation sequence,
* except that it sets the right bits for the MPC823ADS board when SCC2 is used,
* and those for the 860/821 development board for SCC1.
*/
static void
sccsetup(Ctlr *ctlr, SCC *scc, Ether *ether)
{
int i, rcs, tcs, w;
Etherparam *p;
IMM *io;
i = 2*(ctlr->port-1);
io = ioplock();
w = (TXD1|RXD1)<<i; /* TXDn and RXDn in port A */
io->papar |= w; /* enable TXDn and RXDn pins */
io->padir &= ~w;
io->paodr &= ~w; /* not open drain */
w = (CD1|CTS1)<<i; /* CLSN and RENA: CDn and CTSn in port C */
io->pcpar &= ~w; /* enable CLSN (CTSn) and RENA (CDn) */
io->pcdir &= ~w;
io->pcso |= w;
iopunlock();
/* clocks and transceiver control: details depend on the board's wiring */
archetherenable(sccid[ctlr->port], &rcs, &tcs, ether->mbps, ether->fullduplex);
sccnmsi(ctlr->port, rcs, tcs); /* connect the clocks */
p = ctlr->cpm->param;
memset(p, 0, sizeof(*p));
p->rfcr = 0x18;
p->tfcr = 0x18;
p->mrblr = Bufsize;
p->rbase = PADDR(ctlr->rdr);
p->tbase = PADDR(ctlr->tdr);
cpmop(ctlr->cpm, InitRxTx, 0);
p->c_pres = ~0;
p->c_mask = 0xDEBB20E3;
p->crcec = 0;
p->alec = 0;
p->disfc = 0;
p->pads = 0x8888;
p->ret_lim = 0xF;
p->mflr = Rbsize;
p->minflr = ETHERMINTU+4;
p->maxd1 = Bufsize;
p->maxd2 = Bufsize;
p->p_per = 0; /* only moderate aggression */
for(i=0; i<Eaddrlen; i+=2)
p->paddr[2-i/2] = (ether->ea[i+1]<<8)|ether->ea[i]; /* it's not the obvious byte order */
scc->psmr = (2<<10)|(5<<1); /* 32-bit CRC, ignore 22 bits before SFD */
scc->dsr = 0xd555;
scc->gsmrh = 0; /* normal operation */
scc->gsmrl = (1<<28)|(4<<21)|(1<<19)|0xC; /* transmit clock invert, 48 bit preamble, repetitive 10 preamble, ethernet */
eieio();
scc->scce = ~0; /* clear all events */
eieio();
scc->sccm = TXE | RXF | TXB; /* enable interrupts */
eieio();
io = ioplock();
w = RTS1<<(ctlr->port-1); /* enable TENA pin (RTSn) */
io->pbpar |= w;
io->pbdir |= w;
iopunlock();
/* gsmrl enable is deferred until attach */
}
static int
reset(Ether* ether)
{
uchar ea[Eaddrlen];
CPMdev *cpm;
Ctlr *ctlr;
SCC *scc;
if(m->speed < 24){
print("%s ether: system speed must be >= 24MHz for ether use\n", ether->type);
return -1;
}
if(!(ether->port >= 1 && ether->port <= 4)){
print("%s ether: no SCC port %lud\n", ether->type, ether->port);
return -1;
}
/*
* Insist that the platform-specific code provide the Ethernet address
*/
memset(ea, 0, Eaddrlen);
if(memcmp(ea, ether->ea, Eaddrlen) == 0){
print("no ether address");
return -1;
}
cpm = cpmdev(sccid[ether->port]);
if(cpm == nil)
return -1;
ether->irq = VectorCPIC + cpm->irq;
scc = cpm->regs;
ctlr = malloc(sizeof(*ctlr));
ether->ctlr = ctlr;
memset(ctlr, 0, sizeof(*ctlr));
ctlr->cpm = cpm;
ctlr->scc = scc;
ctlr->port = ether->port;
if(ioringinit(ctlr, Nrdre, Ntdre, Bufsize) < 0)
panic("etherscc init");
sccsetup(ctlr, scc, ether);
ether->attach = attach;
ether->closed = closed;
ether->transmit = transmit;
ether->interrupt = interrupt;
ether->ifstat = ifstat;
ether->arg = ether;
ether->promiscuous = promiscuous;
ether->multicast = multicast;
return 0;
}
void
etherscclink(void)
{
addethercard("SCC", reset);
}