soc.c

讲述linux的初始化过程

/* soc.c: Sparc SUNW,soc (Serial Optical Channel) Fibre Channel Sbus adapter support.
 *
 * Copyright (C) 1996,1997,1999 Jakub Jelinek ([e-mail])
 * Copyright (C) 1997,1998 Jirka Hanika ([e-mail])
 *
 * Sources:
 *	Fibre Channel Physical & Signaling Interface (FC-PH), dpANS, 1994
 *	dpANS Fibre Channel Protocol for SCSI (X3.269-199X), Rev. 012, 1995
 *
 * Supported hardware:
 *      Tested on SOC sbus card bought with SS1000 in Linux running on SS5 and Ultra1. 
 *      For SOC sbus cards, you have to make sure your FCode is 1.52 or later.
 *      If you have older FCode, you should try to upgrade or get SOC microcode from Sun
 *      (the microcode is present in Solaris soc driver as well). In that case you need
 *      to #define HAVE_SOC_UCODE and format the microcode into soc_asm.c. For the exact
 *      format mail me and I will tell you. I cannot offer you the actual microcode though,
 *      unless Sun confirms they don't mind.
 */

static char *version =
        "soc.c:v1.3 9/Feb/99 Jakub Jelinek ([e-mail]), Jirka Hanika ([e-mail])\n";

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/interrupt.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/in.h>
#include <linux/malloc.h>
#include <linux/string.h>
#include <linux/init.h>
#include <asm/bitops.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <linux/errno.h>
#include <asm/byteorder.h>

#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/auxio.h>
#include <asm/pgtable.h>
#include <asm/irq.h>

/* #define SOCDEBUG */
/* #define HAVE_SOC_UCODE */

#include "fcp_impl.h"
#include "soc.h"
#ifdef HAVE_SOC_UCODE
#include "soc_asm.h"
#endif

#define soc_printk printk ("soc%d: ", s->soc_no); printk 

#ifdef SOCDEBUG
#define SOD(x)  soc_printk x;
#else
#define SOD(x)
#endif

#define for_each_soc(s) for (s = socs; s; s = s->next)
struct soc *socs = NULL;

static inline void soc_disable(struct soc *s)
{
	sbus_writel(0, s->regs + IMASK);
	sbus_writel(SOC_CMD_SOFT_RESET, s->regs + CMD);
}

static inline void soc_enable(struct soc *s)
{
	SOD(("enable %08x\n", s->cfg))
	sbus_writel(0, s->regs + SAE);
	sbus_writel(s->cfg, s->regs + CFG);
	sbus_writel(SOC_CMD_RSP_QALL, s->regs + CMD);
	SOC_SETIMASK(s, SOC_IMASK_RSP_QALL | SOC_IMASK_SAE);
	SOD(("imask %08lx %08lx\n", s->imask, sbus_readl(s->regs + IMAK)));
}

static void soc_reset(fc_channel *fc)
{
	soc_port *port = (soc_port *)fc;
	struct soc *s = port->s;
	
	/* FIXME */
	soc_disable(s);
	s->req[0].seqno = 1;
	s->req[1].seqno = 1;
	s->rsp[0].seqno = 1;
	s->rsp[1].seqno = 1;
	s->req[0].in = 0;
	s->req[1].in = 0;
	s->rsp[0].in = 0;
	s->rsp[1].in = 0;
	s->req[0].out = 0;
	s->req[1].out = 0;
	s->rsp[0].out = 0;
	s->rsp[1].out = 0;

	/* FIXME */
	soc_enable(s);
}

static void inline soc_solicited (struct soc *s)
{
	fc_hdr fchdr;
	soc_rsp *hwrsp;
	soc_cq *sw_cq;
	int token;
	int status;
	fc_channel *fc;

	sw_cq = &s->rsp[SOC_SOLICITED_RSP_Q];

	if (sw_cq->pool == NULL)
		sw_cq->pool = (soc_req *)
			(s->xram + xram_get_32low ((xram_p)&sw_cq->hw_cq->address));
	sw_cq->in = xram_get_8 ((xram_p)&sw_cq->hw_cq->in);
	SOD (("soc_solicited, %d pkts arrived\n", (sw_cq->in-sw_cq->out) & sw_cq->last))
	for (;;) {
		hwrsp = (soc_rsp *)sw_cq->pool + sw_cq->out;
		token = xram_get_32low ((xram_p)&hwrsp->shdr.token);
		status = xram_get_32low ((xram_p)&hwrsp->status);
		fc = (fc_channel *)(&s->port[(token >> 11) & 1]);
		
		if (status == SOC_OK) {
			fcp_receive_solicited(fc, token >> 12,
					      token & ((1 << 11) - 1),
					      FC_STATUS_OK, NULL);
		} else {
			xram_copy_from(&fchdr, (xram_p)&hwrsp->fchdr, sizeof(fchdr));
			/* We have intentionally defined FC_STATUS_* constants
			 * to match SOC_* constants, otherwise we'd have to
			 * translate status.
			 */
			fcp_receive_solicited(fc, token >> 12,
					      token & ((1 << 11) - 1),
					      status, &fchdr);
		}
			
		if (++sw_cq->out > sw_cq->last) {
			sw_cq->seqno++;
			sw_cq->out = 0;
		}
		
		if (sw_cq->out == sw_cq->in) {
			sw_cq->in = xram_get_8 ((xram_p)&sw_cq->hw_cq->in);
			if (sw_cq->out == sw_cq->in) {
				/* Tell the hardware about it */
				sbus_writel((sw_cq->out << 24) |
					    (SOC_CMD_RSP_QALL &
					     ~(SOC_CMD_RSP_Q0 << SOC_SOLICITED_RSP_Q)),
					    s->regs + CMD);

				/* Read it, so that we're sure it has been updated */
				sbus_readl(s->regs + CMD);
				sw_cq->in = xram_get_8 ((xram_p)&sw_cq->hw_cq->in);
				if (sw_cq->out == sw_cq->in)
					break;
			}
		}
	}
}

static void inline soc_request (struct soc *s, u32 cmd)
{
	SOC_SETIMASK(s, s->imask & ~(cmd & SOC_CMD_REQ_QALL));
	SOD(("imask %08lx %08lx\n", s->imask, sbus_readl(s->regs + IMASK)));

	SOD(("Queues available %08x OUT %X %X\n", cmd,
	     xram_get_8((xram_p)&s->req[0].hw_cq->out),
	     xram_get_8((xram_p)&s->req[0].hw_cq->out)))
	if (s->port[s->curr_port].fc.state != FC_STATE_OFFLINE) {
		fcp_queue_empty ((fc_channel *)&(s->port[s->curr_port]));
		if (((s->req[1].in + 1) & s->req[1].last) != (s->req[1].out))
			fcp_queue_empty ((fc_channel *)&(s->port[1 - s->curr_port]));
	} else {
		fcp_queue_empty ((fc_channel *)&(s->port[1 - s->curr_port]));
	}
	if (s->port[1 - s->curr_port].fc.state != FC_STATE_OFFLINE)
		s->curr_port ^= 1;
}

static void inline soc_unsolicited (struct soc *s)
{
	soc_rsp *hwrsp, *hwrspc;
	soc_cq *sw_cq;
	int count;
	int status;
	int flags;
	fc_channel *fc;

	sw_cq = &s->rsp[SOC_UNSOLICITED_RSP_Q];
	if (sw_cq->pool == NULL)
		sw_cq->pool = (soc_req *)
			(s->xram + (xram_get_32low ((xram_p)&sw_cq->hw_cq->address)));

	sw_cq->in = xram_get_8 ((xram_p)&sw_cq->hw_cq->in);
	SOD (("soc_unsolicited, %d packets arrived\n", (sw_cq->in - sw_cq->out) & sw_cq->last))
	while (sw_cq->in != sw_cq->out) {
		/* ...real work per entry here... */
		hwrsp = (soc_rsp *)sw_cq->pool + sw_cq->out;

		hwrspc = NULL;
		flags = xram_get_16 ((xram_p)&hwrsp->shdr.flags);
		count = xram_get_8 ((xram_p)&hwrsp->count);
		fc = (fc_channel *)&s->port[flags & SOC_PORT_B];
		SOD(("FC %08lx fcp_state_change %08lx\n",
		     (long)fc, (long)fc->fcp_state_change))
		
		if (count != 1) {
			/* Ugh, continuation entries */
			u8 in;

			if (count != 2) {
				printk("%s: Too many continuations entries %d\n",
				       fc->name, count);
				goto update_out;
			}
			
			in = sw_cq->in;
			if (in < sw_cq->out) in += sw_cq->last + 1;
			if (in < sw_cq->out + 2) {
				/* Ask the hardware if they haven't arrived yet. */
				sbus_writel((sw_cq->out << 24) |
					    (SOC_CMD_RSP_QALL &
					     ~(SOC_CMD_RSP_Q0 << SOC_UNSOLICITED_RSP_Q)),
					    s->regs + CMD);

				/* Read it, so that we're sure it has been updated */
				sbus_readl(s->regs + CMD);
				sw_cq->in = xram_get_8 ((xram_p)&sw_cq->hw_cq->in);
				in = sw_cq->in;
				if (in < sw_cq->out)
					in += sw_cq->last + 1;
				if (in < sw_cq->out + 2) /* Nothing came, let us wait */
					return;
			}
			if (sw_cq->out == sw_cq->last)
				hwrspc = (soc_rsp *)sw_cq->pool;
			else
				hwrspc = hwrsp + 1;
		}
		
		switch (flags & ~SOC_PORT_B) {
		case SOC_STATUS:
			status = xram_get_32low ((xram_p)&hwrsp->status);
			switch (status) {
			case SOC_ONLINE:
				SOD(("State change to ONLINE\n"));
				fcp_state_change(fc, FC_STATE_ONLINE);
				break;
			case SOC_OFFLINE:
				SOD(("State change to OFFLINE\n"));
				fcp_state_change(fc, FC_STATE_OFFLINE);
				break;
			default:
				printk ("%s: Unknown STATUS no %d\n",
					fc->name, status);
				break;
			}
			break;
		case (SOC_UNSOLICITED|SOC_FC_HDR):
			{
				int r_ctl = xram_get_8 ((xram_p)&hwrsp->fchdr);
				unsigned len;
				char buf[64];
				
				if ((r_ctl & 0xf0) == R_CTL_EXTENDED_SVC) {
					len = xram_get_32 ((xram_p)&hwrsp->shdr.bytecnt);
					if (len < 4 || !hwrspc) {
						printk ("%s: Invalid R_CTL %02x "
							"continuation entries\n",
							fc->name, r_ctl);
					} else {
						if (len > 60)
							len = 60;
						xram_copy_from (buf, (xram_p)hwrspc,
								(len + 3) & ~3);
						if (*(u32 *)buf == LS_DISPLAY) {
							int i;
							
							for (i = 4; i < len; i++)
								if (buf[i] == '\n')
									buf[i] = ' ';
							buf[len] = 0;
							printk ("%s message: %s\n",
								fc->name, buf + 4);
						} else {
							printk ("%s: Unknown LS_CMD "
								"%02x\n", fc->name,
								buf[0]);
						}
					}
				} else {
					printk ("%s: Unsolicited R_CTL %02x "
						"not handled\n", fc->name, r_ctl);
				}
			}
			break;
		default:
			printk ("%s: Unexpected flags %08x\n", fc->name, flags);
			break;
		};
update_out:
		if (++sw_cq->out > sw_cq->last) {
			sw_cq->seqno++;
			sw_cq->out = 0;
		}
		
		if (hwrspc) {
			if (++sw_cq->out > sw_cq->last) {
				sw_cq->seqno++;
				sw_cq->out = 0;
			}
		}
		
		if (sw_cq->out == sw_cq->in) {
			sw_cq->in = xram_get_8 ((xram_p)&sw_cq->hw_cq->in);
			if (sw_cq->out == sw_cq->in) {
				/* Tell the hardware about it */
				sbus_writel((sw_cq->out << 24) |
					    (SOC_CMD_RSP_QALL &
					     ~(SOC_CMD_RSP_Q0 << SOC_UNSOLICITED_RSP_Q)),
					    s->regs + CMD);

				/* Read it, so that we're sure it has been updated */
				sbus_readl(s->regs + CMD);
				sw_cq->in = xram_get_8 ((xram_p)&sw_cq->hw_cq->in);
			}
		}
	}
}

static void soc_intr(int irq, void *dev_id, struct pt_regs *regs)
{
	u32 cmd;
	unsigned long flags;
	register struct soc *s = (struct soc *)dev_id;

	spin_lock_irqsave(&io_request_lock, flags);
	cmd = sbus_readl(s->regs + CMD);
	for (; (cmd = SOC_INTR (s, cmd)); cmd = sbus_readl(s->regs + CMD)) {
		if (cmd & SOC_CMD_RSP_Q1) soc_unsolicited (s);
		if (cmd & SOC_CMD_RSP_Q0) soc_solicited (s);
		if (cmd & SOC_CMD_REQ_QALL) soc_request (s, cmd);
	}
	spin_unlock_irqrestore(&io_request_lock, flags);
}

#define TOKEN(proto, port, token) (((proto)<<12)|(token)|(port))

static int soc_hw_enque (fc_channel *fc, fcp_cmnd *fcmd)
{
	soc_port *port = (soc_port *)fc;
	struct soc *s = port->s;
	int qno;
	soc_cq *sw_cq;
	int cq_next_in;
	soc_req *request;
	fc_hdr *fch;
	int i;

	if (fcmd->proto == TYPE_SCSI_FCP)
		qno = 1;
	else
		qno = 0;
	SOD(("Putting a FCP packet type %d into hw queue %d\n", fcmd->proto, qno))
	if (s->imask & (SOC_IMASK_REQ_Q0 << qno)) {
		SOD(("EIO %08x\n", s->imask))
		return -EIO;
	}
	sw_cq = s->req + qno;
	cq_next_in = (sw_cq->in + 1) & sw_cq->last;
	
	if (cq_next_in == sw_cq->out &&
	    cq_next_in == (sw_cq->out = xram_get_8((xram_p)&sw_cq->hw_cq->out))) {
		SOD(("%d IN %d OUT %d LAST %d\n", qno, sw_cq->in, sw_cq->out, sw_cq->last))
		SOC_SETIMASK(s, s->imask | (SOC_IMASK_REQ_Q0 << qno));
		SOD(("imask %08lx %08lx\n", s->imask, sbus_readl(s->regs + IMASK)));
		/* If queue is full, just say NO */
		return -EBUSY;
	}