/* epic100.c: A SMC 83c170 EPIC/100 fast ethernet driver for Etherboot */
#define LINUX_OUT_MACROS
#include "etherboot.h"
#include "nic.h"
#include "cards.h"
#include "timer.h"
#include "epic100.h"
#undef virt_to_bus
#define virt_to_bus(x) ((unsigned long)x)
#define TX_RING_SIZE 2 /* use at least 2 buffers for TX */
#define RX_RING_SIZE 2
#define PKT_BUF_SZ 1536 /* Size of each temporary Tx/Rx buffer.*/
/*
#define DEBUG_RX
#define DEBUG_TX
#define DEBUG_EEPROM
*/
#define EPIC_DEBUG 0 /* debug level */
/* The EPIC100 Rx and Tx buffer descriptors. */
struct epic_rx_desc {
unsigned short status;
unsigned short rxlength;
unsigned long bufaddr;
unsigned short buflength;
unsigned short control;
unsigned long next;
};
/* description of the tx descriptors control bits commonly used */
#define TD_STDFLAGS TD_LASTDESC
struct epic_tx_desc {
unsigned short status;
unsigned short txlength;
unsigned long bufaddr;
unsigned short buflength;
unsigned short control;
unsigned long next;
};
#define delay(nanosec) do { int _i = 3; while (--_i > 0) \
{ __SLOW_DOWN_IO; }} while (0)
static void epic100_open(void);
static void epic100_init_ring(void);
static void epic100_disable(struct nic *nic);
static int epic100_poll(struct nic *nic);
static void epic100_transmit(struct nic *nic, const char *destaddr,
unsigned int type, unsigned int len, const char *data);
static int read_eeprom(int location);
static int mii_read(int phy_id, int location);
static int ioaddr;
static int command;
static int intstat;
static int intmask;
static int genctl ;
static int eectl ;
static int test ;
static int mmctl ;
static int mmdata ;
static int lan0 ;
static int rxcon ;
static int txcon ;
static int prcdar ;
static int ptcdar ;
static int eththr ;
static unsigned int cur_rx, cur_tx; /* The next free ring entry */
#ifdef DEBUG_EEPROM
static unsigned short eeprom[64];
#endif
static signed char phys[4]; /* MII device addresses. */
static struct epic_rx_desc rx_ring[RX_RING_SIZE];
static struct epic_tx_desc tx_ring[TX_RING_SIZE];
#ifdef USE_LOWMEM_BUFFER
#define rx_packet ((char *)0x10000 - PKT_BUF_SZ * RX_RING_SIZE)
#define tx_packet ((char *)0x10000 - PKT_BUF_SZ * RX_RING_SIZE - PKT_BUF_SZ * TX_RING_SIZE)
#else
static char rx_packet[PKT_BUF_SZ * RX_RING_SIZE];
static char tx_packet[PKT_BUF_SZ * TX_RING_SIZE];
#endif
/***********************************************************************/
/* Externally visible functions */
/***********************************************************************/
static void
epic100_reset(struct nic *nic)
{
/* Soft reset the chip. */
outl(GC_SOFT_RESET, genctl);
}
struct nic*
epic100_probe(struct nic *nic, unsigned short *probeaddrs)
{
unsigned short sum = 0;
unsigned short value;
int i;
unsigned short* ap;
unsigned int phy, phy_idx;
if (probeaddrs == 0 || probeaddrs[0] == 0)
return 0;
/* Ideally we would detect all network cards in slot order. That would
be best done a central PCI probe dispatch, which wouldn't work
well with the current structure. So instead we detect just the
Epic cards in slot order. */
ioaddr = probeaddrs[0] & ~3; /* Mask the bit that says "this is an io addr" */
/* compute all used static epic100 registers address */
command = ioaddr + COMMAND; /* Control Register */
intstat = ioaddr + INTSTAT; /* Interrupt Status */
intmask = ioaddr + INTMASK; /* Interrupt Mask */
genctl = ioaddr + GENCTL; /* General Control */
eectl = ioaddr + EECTL; /* EEPROM Control */
test = ioaddr + TEST; /* Test register (clocks) */
mmctl = ioaddr + MMCTL; /* MII Management Interface Control */
mmdata = ioaddr + MMDATA; /* MII Management Interface Data */
lan0 = ioaddr + LAN0; /* MAC address. (0x40-0x48) */
rxcon = ioaddr + RXCON; /* Receive Control */
txcon = ioaddr + TXCON; /* Transmit Control */
prcdar = ioaddr + PRCDAR; /* PCI Receive Current Descr Address */
ptcdar = ioaddr + PTCDAR; /* PCI Transmit Current Descr Address */
eththr = ioaddr + ETHTHR; /* Early Transmit Threshold */
/* Reset the chip & bring it out of low-power mode. */
outl(GC_SOFT_RESET, genctl);
/* Disable ALL interrupts by setting the interrupt mask. */
outl(INTR_DISABLE, intmask);
/*
* set the internal clocks:
* Application Note 7.15 says:
* In order to set the CLOCK TEST bit in the TEST register,
* perform the following:
*
* Write 0x0008 to the test register at least sixteen
* consecutive times.
*
* The CLOCK TEST bit is Write-Only. Writing it several times
* consecutively insures a successful write to the bit...
*/
for (i = 0; i < 16; i++) {
outl(0x00000008, test);
}
#ifdef DEBUG_EEPROM
for (i = 0; i < 64; i++) {
value = read_eeprom(i);
eeprom[i] = value;
sum += value;
}
#if (EPIC_DEBUG > 1)
printf("EEPROM contents\n");
for (i = 0; i < 64; i++) {
printf(" %hhX%s", eeprom[i], i % 16 == 15 ? "\n" : "");
}
#endif
#endif
/* This could also be read from the EEPROM. */
ap = (unsigned short*)nic->node_addr;
for (i = 0; i < 3; i++)
*ap++ = inw(lan0 + i*4);
printf(" I/O %#hX %! ", ioaddr, nic->node_addr);
/* Find the connected MII xcvrs. */
for (phy = 0, phy_idx = 0; phy < 32 && phy_idx < sizeof(phys); phy++) {
int mii_status = mii_read(phy, 0);
if (mii_status != 0xffff && mii_status != 0x0000) {
phys[phy_idx++] = phy;
#if (EPIC_DEBUG > 1)
printf("MII transceiver found at address %d.\n", phy);
#endif
}
}
if (phy_idx == 0) {
#if (EPIC_DEBUG > 1)
printf("***WARNING***: No MII transceiver found!\n");
#endif
/* Use the known PHY address of the EPII. */
phys[0] = 3;
}
epic100_open();
nic->reset = epic100_reset;
nic->poll = epic100_poll;
nic->transmit = epic100_transmit;
nic->disable = epic100_disable;
return nic;
}
static void
epic100_open(void)
{
int mii_reg5;
int full_duplex = 0;
unsigned long tmp;
epic100_init_ring();
/* Pull the chip out of low-power mode, and set for PCI read multiple. */
outl(GC_RX_FIFO_THR_64 | GC_MRC_READ_MULT | GC_ONE_COPY, genctl);
outl(TX_FIFO_THRESH, eththr);
tmp = TC_EARLY_TX_ENABLE | TX_SLOT_TIME;
mii_reg5 = mii_read(phys[0], 5);
if (mii_reg5 != 0xffff && (mii_reg5 & 0x0100)) {
full_duplex = 1;
printf(" full-duplex mode");
tmp |= TC_LM_FULL_DPX;
} else
tmp |= TC_LM_NORMAL;
outl(tmp, txcon);
/* Give adress of RX and TX ring to the chip */
outl(virt_to_bus(&rx_ring), prcdar);
outl(virt_to_bus(&tx_ring), ptcdar);
/* Start the chip's Rx process: receive unicast and broadcast */
outl(0x04, rxcon);
outl(CR_START_RX | CR_QUEUE_RX, command);
putchar('\n');
}
/* Initialize the Rx and Tx rings. */
static void
epic100_init_ring(void)
{
int i;
char* p;
cur_rx = cur_tx = 0;
p = &rx_packet[0];
for (i = 0; i < RX_RING_SIZE; i++) {
rx_ring[i].status = RRING_OWN; /* Owned by Epic chip */
rx_ring[i].buflength = PKT_BUF_SZ;
rx_ring[i].bufaddr = virt_to_bus(p + (PKT_BUF_SZ * i));
rx_ring[i].control = 0;
rx_ring[i].next = virt_to_bus(&(rx_ring[i + 1]) );
}
/* Mark the last entry as wrapping the ring. */
rx_ring[i-1].next = virt_to_bus(&rx_ring[0]);
/*
*The Tx buffer descriptor is filled in as needed,
* but we do need to clear the ownership bit.
*/
p = &tx_packet[0];
for (i = 0; i < TX_RING_SIZE; i++) {
tx_ring[i].status = 0; /* Owned by CPU */
tx_ring[i].bufaddr = virt_to_bus(p + (PKT_BUF_SZ * i));
tx_ring[i].control = TD_STDFLAGS;
tx_ring[i].next = virt_to_bus(&(tx_ring[i + 1]) );
}
tx_ring[i-1].next = virt_to_bus(&tx_ring[0]);
}
/* function: epic100_transmit
* This transmits a packet.
*
* Arguments: char d[6]: destination ethernet address.
* unsigned short t: ethernet protocol type.
* unsigned short s: size of the data-part of the packet.
* char *p: the data for the packet.
* returns: void.
*/
static void
epic100_transmit(struct nic *nic, const char *destaddr, unsigned int type,
unsigned int len, const char *data)
{
unsigned short nstype;
char* txp;
int entry;
/* Calculate the next Tx descriptor entry. */
entry = cur_tx % TX_RING_SIZE;
if ((tx_ring[entry].status & TRING_OWN) == TRING_OWN) {
printf("eth_transmit: Unable to transmit. status=%hX. Resetting...\n",
tx_ring[entry].status);
epic100_open();
return;
}
txp = (char*)tx_ring[entry].bufaddr;
memcpy(txp, destaddr, ETH_ALEN);
memcpy(txp + ETH_ALEN, nic->node_addr, ETH_ALEN);
nstype = htons(type);
memcpy(txp + 12, (char*)&nstype, 2);
memcpy(txp + ETH_HLEN, data, len);
len += ETH_HLEN;
/*
* Caution: the write order is important here,
* set the base address with the "ownership"
* bits last.
*/
tx_ring[entry].txlength = (len >= 60 ? len : 60);
tx_ring[entry].buflength = len;
tx_ring[entry].status = TRING_OWN; /* Pass ownership to the chip. */
cur_tx++;
/* Trigger an immediate transmit demand. */
outl(CR_QUEUE_TX, command);
load_timer2(10*TICKS_PER_MS); /* timeout 10 ms for transmit */
while ((tx_ring[entry].status & TRING_OWN) && timer2_running())
/* Wait */;
if ((tx_ring[entry].status & TRING_OWN) != 0)
printf("Oops, transmitter timeout, status=%hX\n",
tx_ring[entry].status);
}
/* function: epic100_poll / eth_poll
* This receives a packet from the network.
*
* Arguments: none
*
* returns: 1 if a packet was received.
* 0 if no pacet was received.
* side effects:
* returns the packet in the array nic->packet.
* returns the length of the packet in nic->packetlen.
*/
static int
epic100_poll(struct nic *nic)
{
int entry;
int status;
int retcode;
entry = cur_rx % RX_RING_SIZE;
if ((status = rx_ring[entry].status & RRING_OWN) == RRING_OWN)
return (0);
/* We own the next entry, it's a new packet. Send it up. */
#if (EPIC_DEBUG > 4)
printf("epic_poll: entry %d status %hX\n", entry, status);
#endif
cur_rx++;
if (status & 0x2000) {
printf("epic_poll: Giant packet\n");
retcode = 0;
} else if (status & 0x0006) {
/* Rx Frame errors are counted in hardware. */
printf("epic_poll: Frame received with errors\n");
retcode = 0;
} else {
/* Omit the four octet CRC from the length. */
nic->packetlen = rx_ring[entry].rxlength - 4;
memcpy(nic->packet, (char*)rx_ring[entry].bufaddr, nic->packetlen);
retcode = 1;
}
/* Clear all error sources. */
outl(status & INTR_CLEARERRS, intstat);
/* Give the descriptor back to the chip */
rx_ring[entry].status = RRING_OWN;
/* Restart Receiver */
outl(CR_START_RX | CR_QUEUE_RX, command);
return retcode;
}
static void
epic100_disable(struct nic *nic)
{
}
#ifdef DEBUG_EEPROM
/* Serial EEPROM section. */
/* EEPROM_Ctrl bits. */
#define EE_SHIFT_CLK 0x04 /* EEPROM shift clock. */
#define EE_CS 0x02 /* EEPROM chip select. */
#define EE_DATA_WRITE 0x08 /* EEPROM chip data in. */
#define EE_WRITE_0 0x01
#define EE_WRITE_1 0x09
#define EE_DATA_READ 0x10 /* EEPROM chip data out. */
#define EE_ENB (0x0001 | EE_CS)
/* The EEPROM commands include the alway-set leading bit. */
#define EE_WRITE_CMD (5 << 6)
#define EE_READ_CMD (6 << 6)
#define EE_ERASE_CMD (7 << 6)
#define eeprom_delay(n) delay(n)
static int
read_eeprom(int location)
{
int i;
int retval = 0;
int read_cmd = location | EE_READ_CMD;
outl(EE_ENB & ~EE_CS, eectl);
outl(EE_ENB, eectl);
/* Shift the read command bits out. */
for (i = 10; i >= 0; i--) {
short dataval = (read_cmd & (1 << i)) ? EE_DATA_WRITE : 0;
outl(EE_ENB | dataval, eectl);
eeprom_delay(100);
outl(EE_ENB | dataval | EE_SHIFT_CLK, eectl);
eeprom_delay(150);
outl(EE_ENB | dataval, eectl); /* Finish EEPROM a clock tick. */
eeprom_delay(250);
}
outl(EE_ENB, eectl);
for (i = 16; i > 0; i--) {
outl(EE_ENB | EE_SHIFT_CLK, eectl);
eeprom_delay(100);
retval = (retval << 1) | ((inl(eectl) & EE_DATA_READ) ? 1 : 0);
outl(EE_ENB, eectl);
eeprom_delay(100);
}
/* Terminate the EEPROM access. */
outl(EE_ENB & ~EE_CS, eectl);
return retval;
}
#endif
#define MII_READOP 1
#define MII_WRITEOP 2
static int
mii_read(int phy_id, int location)
{
int i;
outl((phy_id << 9) | (location << 4) | MII_READOP, mmctl);
/* Typical operation takes < 50 ticks. */
for (i = 4000; i > 0; i--)
if ((inl(mmctl) & MII_READOP) == 0)
break;
return inw(mmdata);
}