ref: b5bc6572b0a82c52ab04bcf25e1ed76700deb246
dir: /os/boot/rpcg/etherscc.c/
/*
* SCCn ethernet
*/
#include "u.h"
#include "lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "etherif.h"
enum {
Nrdre = 32, /* receive descriptor ring entries */
Ntdre = 4, /* 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,
/* 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 {
SCC* scc;
int port;
int cpm;
BD* rdr; /* receive descriptor ring */
void* rrb; /* receive ring buffers */
int rdrx; /* index into rdr */
BD* tdr; /* transmit descriptor ring */
void* trb; /* transmit ring buffers */
int tdrx; /* index into tdr */
} Mot;
static Mot mot[MaxEther];
static int sccid[] = {-1, SCC1ID, SCC2ID, SCC3ID, SCC4ID};
static int sccparam[] = {-1, SCC1P, SCC2P, SCC3P, SCC4P};
static int sccreg[] = {-1, 0xA00, 0xA20, 0xA40, 0xA60};
static int sccirq[] = {-1, 0x1E, 0x1D, 0x1C, 0x1B};
static void
attach(Ctlr *ctlr)
{
mot[ctlr->ctlrno].scc->gsmrl |= ENR|ENT;
eieio();
}
static void
transmit(Ctlr *ctlr)
{
int len;
Mot *motp;
Block *b;
BD *tdre;
motp = &mot[ctlr->ctlrno];
while(((tdre = &motp->tdr[motp->tdrx])->status & BDReady) == 0){
b = qget(ctlr->oq);
if(b == 0)
break;
/*
* Copy the packet to the transmit buffer.
*/
len = BLEN(b);
memmove(KADDR(tdre->addr), b->rp, len);
/*
* Give ownership of the descriptor to the chip, increment the
* software ring descriptor pointer and tell the chip to poll.
*/
tdre->length = len;
eieio();
tdre->status = (tdre->status & BDWrap) | BDReady|TxPad|BDInt|BDLast|TxTC;
eieio();
motp->scc->todr = 1<<15; /* transmit now */
eieio();
motp->tdrx = NEXT(motp->tdrx, Ntdre);
freeb(b);
}
}
static void
interrupt(Ureg*, void *ap)
{
int len, events, status;
Mot *motp;
BD *rdre;
Block *b;
Ctlr *ctlr;
ctlr = ap;
motp = &mot[ctlr->ctlrno];
/*
* Acknowledge all interrupts and whine about those that shouldn't
* happen.
*/
events = motp->scc->scce;
eieio();
motp->scc->scce = events;
eieio();
if(events & (TXE|BSY|RXB))
print("ETHER.SCC#%d: scce = 0x%uX\n", ctlr->ctlrno, events);
//print(" %ux|", 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){
rdre = &motp->rdr[motp->rdrx];
while(((status = rdre->status) & BDEmpty) == 0){
if(status & RxError || (status & (BDFirst|BDLast)) != (BDFirst|BDLast)){
//if(status & RxBuff)
// ctlr->buffs++;
if(status & (1<<2))
ctlr->crcs++;
if(status & (1<<1))
ctlr->overflows++;
//print("eth rx: %ux\n", status);
if(status & RxError)
print("~");
else if((status & BDLast) == 0)
print("@");
}
else{
/*
* We have a packet. Read it into the next
* free ring buffer, if any.
*/
len = rdre->length-4;
if((b = iallocb(len)) != 0){
memmove(b->wp, KADDR(rdre->addr), len);
b->wp += len;
etheriq(ctlr, b, 1);
}
}
/*
* Finished with this descriptor, reinitialise it,
* give it back to the chip, then on to the next...
*/
rdre->length = 0;
rdre->status = (rdre->status & BDWrap) | BDEmpty | BDInt;
eieio();
motp->rdrx = NEXT(motp->rdrx, Nrdre);
rdre = &motp->rdr[motp->rdrx];
}
}
/*
* Transmitter interrupt: handle anything queued for a free descriptor.
*/
if(events & TXB)
transmit(ctlr);
if(events & TXE)
cpmop(RestartTx, motp->cpm, 0);
}
static void
ringinit(Mot* motp)
{
int i, x;
/*
* Initialise the receive and transmit buffer rings. The ring
* entries must be aligned on 16-byte boundaries.
*/
if(motp->rdr == 0)
motp->rdr = bdalloc(Nrdre);
if(motp->rrb == 0)
motp->rrb = ialloc(Nrdre*Bufsize, 0);
x = PADDR(motp->rrb);
for(i = 0; i < Nrdre; i++){
motp->rdr[i].length = 0;
motp->rdr[i].addr = x;
motp->rdr[i].status = BDEmpty|BDInt;
x += Bufsize;
}
motp->rdr[i-1].status |= BDWrap;
motp->rdrx = 0;
if(motp->tdr == 0)
motp->tdr = bdalloc(Ntdre);
if(motp->trb == 0)
motp->trb = ialloc(Ntdre*Bufsize, 0);
x = PADDR(motp->trb);
for(i = 0; i < Ntdre; i++){
motp->tdr[i].addr = x;
motp->tdr[i].length = 0;
motp->tdr[i].status = TxPad|BDInt|BDLast|TxTC;
x += Bufsize;
}
motp->tdr[i-1].status |= BDWrap;
motp->tdrx = 0;
}
/*
* 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(Mot *ctlr, SCC *scc, uchar *ea)
{
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(ctlr->cpm, &rcs, &tcs);
sccnmsi(ctlr->port, rcs, tcs); /* connect the clocks */
p = (Etherparam*)KADDR(sccparam[ctlr->port]);
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(InitRxTx, ctlr->cpm, 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] = (ea[i+1]<<8)|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 */
}
/*
* Prepare the SCCx ethernet for booting.
*/
int
sccethreset(Ctlr* ctlr)
{
uchar ea[Eaddrlen];
Mot *motp;
SCC *scc;
char line[50], def[50];
/*
* Since there's no EPROM, insist that the configuration entry
* (see conf.c and flash.c) holds the Ethernet address.
*/
memset(ea, 0, Eaddrlen);
if(memcmp(ea, ctlr->card.ea, Eaddrlen) == 0){
print("no preset Ether address\n");
for(;;){
strcpy(def, "00108bf12900"); /* valid MAC address to be used only for initial configuration */
if(getstr("ether MAC address", line, sizeof(line), def) < 0)
return -1;
if(parseether(ctlr->card.ea, line) >= 0 || ctlr->card.ea[0] == 0xFF)
break;
print("invalid MAC address\n");
}
}
scc = IOREGS(sccreg[ctlr->card.port], SCC);
ctlr->card.irq = VectorCPIC+sccirq[ctlr->card.port];
motp = &mot[ctlr->ctlrno];
motp->scc = scc;
motp->port = ctlr->card.port;
motp->cpm = sccid[ctlr->card.port];
ringinit(motp);
sccsetup(motp, scc, ctlr->card.ea);
/* enable is deferred until attach */
ctlr->card.reset = sccethreset;
ctlr->card.attach = attach;
ctlr->card.transmit = transmit;
ctlr->card.intr = interrupt;
return 0;
}