/*
 * File:  scc.c
 * Description:
 *	Basic ET HW initialization and packet RX/TX routines
 *
 * NOTE  <<<IMPORTANT:  PLEASE READ>>>:
 *     Do not cache Rx/Tx buffers!
 */

/*
 * MPC823 <-> MC68160 Connections:
 *
 * Setup MPC823 to work with MC68160 Enhanced Ethernet
 * Serial Tranceiver as follows:
 *
 * MPC823 Signal                MC68160  Comments
 * ------ ------                -------  --------
 * PA-12 ETHTX    -------->   TX       Eth. Port Transmit Data
 * PB-18 E_TENA   -------->   TENA     Eth. Transmit Port Enable
 * PA-5 ETHTCK    <--------   TCLK     Eth. Port Transmit Clock
 * PA-13 ETHRX    <--------   RX       Eth. Port Receive Data
 * PC-8 E_RENA    <--------   RENA     Eth. Receive Enable
 * PA-6 ETHRCK    <--------   RCLK     Eth. Port Receive Clock
 * PC-9 E_CLSN    <--------   CLSN     Eth. Port Collision Indication
 *
 * FADS Board Signal              MC68160  Comments
 * -----------------              -------  --------
 * (BCSR1) ETHEN*     -------->  CS2      Eth. Port Enable
 * (BSCR4) TPSQEL*    -------->  TPSQEL   Twisted Pair Signal Quality Error Test Enable
 * (BCSR4) TPFLDL*    -------->  TPFLDL   Twisted Pair Full-Duplex
 * (BCSR4) ETHLOOP    -------->  LOOP     Eth. Port Diagnostic Loop-Back
 *
 */

#include <common.h>
#include <malloc.h>
#include <commproc.h>
#include <net.h>
#include <command.h>

#if defined(CONFIG_CMD_NET) && defined(SCC_ENET)

/* Ethernet Transmit and Receive Buffers */
#define DBUF_LENGTH  1520

#define TX_BUF_CNT 2

#define TOUT_LOOP 10000	/* 10 ms to have a packet sent */

static char txbuf[DBUF_LENGTH];

static uint rxIdx;	/* index of the current RX buffer */
static uint txIdx;	/* index of the current TX buffer */

/*
  * SCC Ethernet Tx and Rx buffer descriptors allocated at the
  *  immr->udata_bd address on Dual-Port RAM
  * Provide for Double Buffering
  */

typedef volatile struct CommonBufferDescriptor {
    cbd_t rxbd[PKTBUFSRX];	/* Rx BD */
    cbd_t txbd[TX_BUF_CNT];	/* Tx BD */
} RTXBD;

static RTXBD *rtx;

static int scc_send(struct eth_device *dev, void *packet, int length);
static int scc_recv(struct eth_device* dev);
static int scc_init (struct eth_device* dev, bd_t * bd);
static void scc_halt(struct eth_device* dev);

int scc_initialize(bd_t *bis)
{
	struct eth_device* dev;

	dev = (struct eth_device*) malloc(sizeof *dev);
	memset(dev, 0, sizeof *dev);

	sprintf(dev->name, "SCC");
	dev->iobase = 0;
	dev->priv   = 0;
	dev->init   = scc_init;
	dev->halt   = scc_halt;
	dev->send   = scc_send;
	dev->recv   = scc_recv;

	eth_register(dev);

	return 1;
}

static int scc_send(struct eth_device *dev, void *packet, int length)
{
	int i, j=0;
#if 0
	volatile char *in, *out;
#endif

	/* section 16.9.23.3
	 * Wait for ready
	 */
#if 0
	while (rtx->txbd[txIdx].cbd_sc & BD_ENET_TX_READY);
	out = (char *)(rtx->txbd[txIdx].cbd_bufaddr);
	in = packet;
	for(i = 0; i < length; i++) {
		*out++ = *in++;
	}
	rtx->txbd[txIdx].cbd_datlen = length;
	rtx->txbd[txIdx].cbd_sc |= (BD_ENET_TX_READY | BD_ENET_TX_LAST);
	while (rtx->txbd[txIdx].cbd_sc & BD_ENET_TX_READY) j++;

#ifdef ET_DEBUG
	printf("cycles: %d    status: %x\n", j, rtx->txbd[txIdx].cbd_sc);
#endif
	i = (rtx->txbd[txIdx++].cbd_sc & BD_ENET_TX_STATS) /* return only status bits */;

	/* wrap around buffer index when necessary */
	if (txIdx >= TX_BUF_CNT) txIdx = 0;
#endif

	while ((rtx->txbd[txIdx].cbd_sc & BD_ENET_TX_READY) && (j<TOUT_LOOP)) {
		udelay (1);	/* will also trigger Wd if needed */
		j++;
	}
	if (j>=TOUT_LOOP) printf("TX not ready\n");
	rtx->txbd[txIdx].cbd_bufaddr = (uint)packet;
	rtx->txbd[txIdx].cbd_datlen = length;
	rtx->txbd[txIdx].cbd_sc |= (BD_ENET_TX_READY | BD_ENET_TX_LAST |BD_ENET_TX_WRAP);
	while ((rtx->txbd[txIdx].cbd_sc & BD_ENET_TX_READY) && (j<TOUT_LOOP)) {
		udelay (1);	/* will also trigger Wd if needed */
		j++;
	}
	if (j>=TOUT_LOOP) printf("TX timeout\n");
#ifdef ET_DEBUG
	printf("cycles: %d    status: %x\n", j, rtx->txbd[txIdx].cbd_sc);
#endif
	i = (rtx->txbd[txIdx].cbd_sc & BD_ENET_TX_STATS) /* return only status bits */;
	return i;
}

static int scc_recv (struct eth_device *dev)
{
	int length;

	for (;;) {
		/* section 16.9.23.2 */
		if (rtx->rxbd[rxIdx].cbd_sc & BD_ENET_RX_EMPTY) {
			length = -1;
			break;	/* nothing received - leave for() loop */
		}

		length = rtx->rxbd[rxIdx].cbd_datlen;

		if (rtx->rxbd[rxIdx].cbd_sc & 0x003f) {
#ifdef ET_DEBUG
			printf ("err: %x\n", rtx->rxbd[rxIdx].cbd_sc);
#endif
		} else {
			/* Pass the packet up to the protocol layers. */
			net_process_received_packet(net_rx_packets[rxIdx],
						    length - 4);
		}


		/* Give the buffer back to the SCC. */
		rtx->rxbd[rxIdx].cbd_datlen = 0;

		/* wrap around buffer index when necessary */
		if ((rxIdx + 1) >= PKTBUFSRX) {
			rtx->rxbd[PKTBUFSRX - 1].cbd_sc =
				(BD_ENET_RX_WRAP | BD_ENET_RX_EMPTY);
			rxIdx = 0;
		} else {
			rtx->rxbd[rxIdx].cbd_sc = BD_ENET_RX_EMPTY;
			rxIdx++;
		}
	}
	return length;
}

/**************************************************************
  *
  * SCC Ethernet Initialization Routine
  *
  *************************************************************/

static int scc_init (struct eth_device *dev, bd_t * bis)
{

	int i;
	scc_enet_t *pram_ptr;

	volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;

	pram_ptr = (scc_enet_t *) & (immr->im_cpm.cp_dparam[PROFF_ENET]);

	rxIdx = 0;
	txIdx = 0;

	if (!rtx) {
#ifdef CONFIG_SYS_ALLOC_DPRAM
		rtx = (RTXBD *) (immr->im_cpm.cp_dpmem +
				 dpram_alloc_align (sizeof (RTXBD), 8));
#else
		rtx = (RTXBD *) (immr->im_cpm.cp_dpmem + CPM_SCC_BASE);
#endif
	}

#if (defined(PA_ENET_RXD) && defined(PA_ENET_TXD))
	/* Configure port A pins for Txd and Rxd.
	 */
	immr->im_ioport.iop_papar |= (PA_ENET_RXD | PA_ENET_TXD);
	immr->im_ioport.iop_padir &= ~(PA_ENET_RXD | PA_ENET_TXD);
	immr->im_ioport.iop_paodr &= ~PA_ENET_TXD;
#elif (defined(PB_ENET_RXD) && defined(PB_ENET_TXD))
	/* Configure port B pins for Txd and Rxd.
	 */
	immr->im_cpm.cp_pbpar |= (PB_ENET_RXD | PB_ENET_TXD);
	immr->im_cpm.cp_pbdir &= ~(PB_ENET_RXD | PB_ENET_TXD);
	immr->im_cpm.cp_pbodr &= ~PB_ENET_TXD;
#else
#error Configuration Error: exactly ONE of PA_ENET_[RT]XD, PB_ENET_[RT]XD must be defined
#endif

#if defined(PC_ENET_LBK)
	/* Configure port C pins to disable External Loopback
	 */
	immr->im_ioport.iop_pcpar &= ~PC_ENET_LBK;
	immr->im_ioport.iop_pcdir |= PC_ENET_LBK;
	immr->im_ioport.iop_pcso &= ~PC_ENET_LBK;
	immr->im_ioport.iop_pcdat &= ~PC_ENET_LBK;	/* Disable Loopback */
#endif /* PC_ENET_LBK */

	/* Configure port C pins to enable CLSN and RENA.
	 */
	immr->im_ioport.iop_pcpar &= ~(PC_ENET_CLSN | PC_ENET_RENA);
	immr->im_ioport.iop_pcdir &= ~(PC_ENET_CLSN | PC_ENET_RENA);
	immr->im_ioport.iop_pcso |= (PC_ENET_CLSN | PC_ENET_RENA);

	/* Configure port A for TCLK and RCLK.
	 */
	immr->im_ioport.iop_papar |= (PA_ENET_TCLK | PA_ENET_RCLK);
	immr->im_ioport.iop_padir &= ~(PA_ENET_TCLK | PA_ENET_RCLK);

	/*
	 * Configure Serial Interface clock routing -- see section 16.7.5.3
	 * First, clear all SCC bits to zero, then set the ones we want.
	 */

	immr->im_cpm.cp_sicr &= ~SICR_ENET_MASK;
	immr->im_cpm.cp_sicr |= SICR_ENET_CLKRT;


	/*
	 * Initialize SDCR -- see section 16.9.23.7
	 * SDMA configuration register
	 */
	immr->im_siu_conf.sc_sdcr = 0x01;


	/*
	 * Setup SCC Ethernet Parameter RAM
	 */

	pram_ptr->sen_genscc.scc_rfcr = 0x18;	/* Normal Operation and Mot byte ordering */
	pram_ptr->sen_genscc.scc_tfcr = 0x18;	/* Mot byte ordering, Normal access */

	pram_ptr->sen_genscc.scc_mrblr = DBUF_LENGTH;	/* max. ET package len 1520 */

	pram_ptr->sen_genscc.scc_rbase = (unsigned int) (&rtx->rxbd[0]);	/* Set RXBD tbl start at Dual Port */
	pram_ptr->sen_genscc.scc_tbase = (unsigned int) (&rtx->txbd[0]);	/* Set TXBD tbl start at Dual Port */

	/*
	 * Setup Receiver Buffer Descriptors (13.14.24.18)
	 * Settings:
	 *     Empty, Wrap
	 */

	for (i = 0; i < PKTBUFSRX; i++) {
		rtx->rxbd[i].cbd_sc = BD_ENET_RX_EMPTY;
		rtx->rxbd[i].cbd_datlen = 0;	/* Reset */
		rtx->rxbd[i].cbd_bufaddr = (uint) net_rx_packets[i];
	}

	rtx->rxbd[PKTBUFSRX - 1].cbd_sc |= BD_ENET_RX_WRAP;

	/*
	 * Setup Ethernet Transmitter Buffer Descriptors (13.14.24.19)
	 * Settings:
	 *    Add PADs to Short FRAMES, Wrap, Last, Tx CRC
	 */

	for (i = 0; i < TX_BUF_CNT; i++) {
		rtx->txbd[i].cbd_sc =
			(BD_ENET_TX_PAD | BD_ENET_TX_LAST | BD_ENET_TX_TC);
		rtx->txbd[i].cbd_datlen = 0;	/* Reset */
		rtx->txbd[i].cbd_bufaddr = (uint) (&txbuf[0]);
	}

	rtx->txbd[TX_BUF_CNT - 1].cbd_sc |= BD_ENET_TX_WRAP;

	/*
	 * Enter Command:  Initialize Rx Params for SCC
	 */

	do {			/* Spin until ready to issue command    */
		__asm__ ("eieio");
	} while (immr->im_cpm.cp_cpcr & CPM_CR_FLG);
	/* Issue command */
	immr->im_cpm.cp_cpcr =
		((CPM_CR_INIT_RX << 8) | (CPM_CR_ENET << 4) | CPM_CR_FLG);
	do {			/* Spin until command processed         */
		__asm__ ("eieio");
	} while (immr->im_cpm.cp_cpcr & CPM_CR_FLG);

	/*
	 * Ethernet Specific Parameter RAM
	 *     see table 13-16, pg. 660,
	 *     pg. 681 (example with suggested settings)
	 */

	pram_ptr->sen_cpres = ~(0x0);	/* Preset CRC */
	pram_ptr->sen_cmask = 0xdebb20e3;	/* Constant Mask for CRC */
	pram_ptr->sen_crcec = 0x0;	/* Error Counter CRC (unused) */
	pram_ptr->sen_alec = 0x0;	/* Alignment Error Counter (unused) */
	pram_ptr->sen_disfc = 0x0;	/* Discard Frame Counter (unused) */
	pram_ptr->sen_pads = 0x8888;	/* Short Frame PAD Characters */

	pram_ptr->sen_retlim = 15;	/* Retry Limit Threshold */
	pram_ptr->sen_maxflr = 1518;	/* MAX Frame Length Register */
	pram_ptr->sen_minflr = 64;	/* MIN Frame Length Register */

	pram_ptr->sen_maxd1 = DBUF_LENGTH;	/* MAX DMA1 Length Register */
	pram_ptr->sen_maxd2 = DBUF_LENGTH;	/* MAX DMA2 Length Register */

	pram_ptr->sen_gaddr1 = 0x0;	/* Group Address Filter 1 (unused) */
	pram_ptr->sen_gaddr2 = 0x0;	/* Group Address Filter 2 (unused) */
	pram_ptr->sen_gaddr3 = 0x0;	/* Group Address Filter 3 (unused) */
	pram_ptr->sen_gaddr4 = 0x0;	/* Group Address Filter 4 (unused) */

#define ea eth_get_ethaddr()
	pram_ptr->sen_paddrh = (ea[5] << 8) + ea[4];
	pram_ptr->sen_paddrm = (ea[3] << 8) + ea[2];
	pram_ptr->sen_paddrl = (ea[1] << 8) + ea[0];
#undef ea

	pram_ptr->sen_pper = 0x0;	/* Persistence (unused) */
	pram_ptr->sen_iaddr1 = 0x0;	/* Individual Address Filter 1 (unused) */
	pram_ptr->sen_iaddr2 = 0x0;	/* Individual Address Filter 2 (unused) */
	pram_ptr->sen_iaddr3 = 0x0;	/* Individual Address Filter 3 (unused) */
	pram_ptr->sen_iaddr4 = 0x0;	/* Individual Address Filter 4 (unused) */
	pram_ptr->sen_taddrh = 0x0;	/* Tmp Address (MSB) (unused) */
	pram_ptr->sen_taddrm = 0x0;	/* Tmp Address (unused) */
	pram_ptr->sen_taddrl = 0x0;	/* Tmp Address (LSB) (unused) */

	/*
	 * Enter Command:  Initialize Tx Params for SCC
	 */

	do {			/* Spin until ready to issue command    */
		__asm__ ("eieio");
	} while (immr->im_cpm.cp_cpcr & CPM_CR_FLG);
	/* Issue command */
	immr->im_cpm.cp_cpcr =
		((CPM_CR_INIT_TX << 8) | (CPM_CR_ENET << 4) | CPM_CR_FLG);
	do {			/* Spin until command processed         */
		__asm__ ("eieio");
	} while (immr->im_cpm.cp_cpcr & CPM_CR_FLG);

	/*
	 * Mask all Events in SCCM - we use polling mode
	 */
	immr->im_cpm.cp_scc[SCC_ENET].scc_sccm = 0;

	/*
	 * Clear Events in SCCE -- Clear bits by writing 1's
	 */

	immr->im_cpm.cp_scc[SCC_ENET].scc_scce = ~(0x0);


	/*
	 * Initialize GSMR High 32-Bits
	 * Settings:  Normal Mode
	 */

	immr->im_cpm.cp_scc[SCC_ENET].scc_gsmrh = 0;

	/*
	 * Initialize GSMR Low 32-Bits, but do not Enable Transmit/Receive
	 * Settings:
	 *     TCI = Invert
	 *     TPL =  48 bits
	 *     TPP = Repeating 10's
	 *     MODE = Ethernet
	 */

	immr->im_cpm.cp_scc[SCC_ENET].scc_gsmrl = (SCC_GSMRL_TCI |
						   SCC_GSMRL_TPL_48 |
						   SCC_GSMRL_TPP_10 |
						   SCC_GSMRL_MODE_ENET);

	/*
	 * Initialize the DSR -- see section 13.14.4 (pg. 513) v0.4
	 */

	immr->im_cpm.cp_scc[SCC_ENET].scc_dsr = 0xd555;

	/*
	 * Initialize the PSMR
	 * Settings:
	 *  CRC = 32-Bit CCITT
	 *  NIB = Begin searching for SFD 22 bits after RENA
	 *  FDE = Full Duplex Enable
	 *  LPB = Loopback Enable (Needed when FDE is set)
	 *  BRO = Reject broadcast packets
	 *  PROMISCOUS = Catch all packets regardless of dest. MAC adress
	 */
	immr->im_cpm.cp_scc[SCC_ENET].scc_psmr = SCC_PSMR_ENCRC |
		SCC_PSMR_NIB22 |
#if defined(CONFIG_SCC_ENET_FULL_DUPLEX)
		SCC_PSMR_FDE | SCC_PSMR_LPB |
#endif
#if defined(CONFIG_SCC_ENET_NO_BROADCAST)
		SCC_PSMR_BRO |
#endif
#if defined(CONFIG_SCC_ENET_PROMISCOUS)
		SCC_PSMR_PRO |
#endif
		0;

	/*
	 * Configure Ethernet TENA Signal
	 */

#if (defined(PC_ENET_TENA) && !defined(PB_ENET_TENA))
	immr->im_ioport.iop_pcpar |= PC_ENET_TENA;
	immr->im_ioport.iop_pcdir &= ~PC_ENET_TENA;
#elif (defined(PB_ENET_TENA) && !defined(PC_ENET_TENA))
	immr->im_cpm.cp_pbpar |= PB_ENET_TENA;
	immr->im_cpm.cp_pbdir |= PB_ENET_TENA;
#else
#error Configuration Error: exactly ONE of PB_ENET_TENA, PC_ENET_TENA must be defined
#endif

	/*
	 * Set the ENT/ENR bits in the GSMR Low -- Enable Transmit/Receive
	 */

	immr->im_cpm.cp_scc[SCC_ENET].scc_gsmrl |=
		(SCC_GSMRL_ENR | SCC_GSMRL_ENT);

	return 1;
}


static void scc_halt (struct eth_device *dev)
{
	volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;

	immr->im_cpm.cp_scc[SCC_ENET].scc_gsmrl &=
		~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);

	immr->im_ioport.iop_pcso  &=  ~(PC_ENET_CLSN | PC_ENET_RENA);
}

#if 0
void restart (void)
{
	volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;

	immr->im_cpm.cp_scc[SCC_ENET].scc_gsmrl |=
		(SCC_GSMRL_ENR | SCC_GSMRL_ENT);
}
#endif
#endif