shuberror.c

一个2.4.21版本的嵌入式linux内核

/* $Id: shuberror.c,v 1.1 2002/02/28 17:31:25 marcelo Exp $
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1992 - 1997, 2000,2002 Silicon Graphics, Inc. All rights reserved.
 */


#include <linux/types.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <asm/irq.h>
#include <asm/smp.h>
#include <asm/sn/sgi.h>
#include <asm/sn/io.h>
#include <asm/sn/iograph.h>
#include <asm/sn/invent.h>
#include <asm/sn/hcl.h>
#include <asm/sn/labelcl.h>
#include <asm/sn/sn_private.h>
#include <asm/sn/klconfig.h>
#include <asm/sn/sn_cpuid.h>
#include <asm/sn/pci/pciio.h>
#include <asm/sn/pci/pcibr.h>
#include <asm/sn/xtalk/xtalk.h>
#include <asm/sn/pci/pcibr_private.h>
#include <asm/sn/intr.h>
#include <asm/sn/ioerror.h>
#include <asm/sn/sn2/shubio.h>
#include <asm/sn/bte.h>

extern void hubni_eint_init(cnodeid_t cnode);
extern void hubii_eint_init(cnodeid_t cnode);
extern void hubii_eint_handler (int irq, void *arg, struct pt_regs *ep);
int hubiio_crb_error_handler(devfs_handle_t hub_v, hubinfo_t hinfo);
int hubiio_prb_error_handler(devfs_handle_t hub_v, hubinfo_t hinfo);
extern void bte_crb_error_handler(devfs_handle_t hub_v, int btenum, int crbnum, ioerror_t *ioe, int bteop);

extern int maxcpus;

#define HUB_ERROR_PERIOD        (120 * HZ)      /* 2 minutes */

#ifdef BUS_INT_WAR
void sn_add_polled_interrupt(int irq, int interval);
void sn_delete_polled_interrupt(int irq);
extern int bus_int_war_ide_irq;
#endif


void
hub_error_clear(nasid_t nasid)
{
	int i;
	hubreg_t idsr;

    /*
     * Make sure spurious write response errors are cleared
     * (values are from hub_set_prb())
     */
    for (i = 0; i <= HUB_WIDGET_ID_MAX - HUB_WIDGET_ID_MIN + 1; i++) {
        iprb_t prb;

	prb.iprb_regval = REMOTE_HUB_L(nasid, IIO_IOPRB_0 + (i * sizeof(hubreg_t)));

        /* Clear out some fields */
        prb.iprb_ovflow = 1;
        prb.iprb_bnakctr = 0;
        prb.iprb_anakctr = 0;

        prb.iprb_xtalkctr = 3;  /* approx. PIO credits for the widget */

        REMOTE_HUB_S(nasid, IIO_IOPRB_0 + (i * sizeof(hubreg_t)), prb.iprb_regval);
    }

    REMOTE_HUB_S(nasid, IIO_IO_ERR_CLR, -1);
    idsr = REMOTE_HUB_L(nasid, IIO_IIDSR);
    REMOTE_HUB_S(nasid, IIO_IIDSR, (idsr & ~(IIO_IIDSR_SENT_MASK)));

}


/*
 * Function	: hub_error_init
 * Purpose	: initialize the error handling requirements for a given hub.
 * Parameters	: cnode, the compact nodeid.
 * Assumptions	: Called only once per hub, either by a local cpu. Or by a 
 *			remote cpu, when this hub is headless.(cpuless)
 * Returns	: None
 */

void
hub_error_init(cnodeid_t cnode)
{
	nasid_t nasid;

    nasid = cnodeid_to_nasid(cnode);
    hub_error_clear(nasid);


    /*
     * Now setup the hub ii error interrupt handler.
     */

    hubii_eint_init(cnode);

    return;
}

/*
 * Function	: hubii_eint_init
 * Parameters	: cnode
 * Purpose	: to initialize the hub iio error interrupt.
 * Assumptions	: Called once per hub, by the cpu which will ultimately
 *			handle this interrupt.
 * Returns	: None.
 */


void
hubii_eint_init(cnodeid_t cnode)
{
    int			bit, rv;
    ii_iidsr_u_t    	hubio_eint;
    hubinfo_t		hinfo; 
    cpuid_t		intr_cpu;
    devfs_handle_t 	hub_v;
    int bit_pos_to_irq(int bit);


    hub_v = (devfs_handle_t)cnodeid_to_vertex(cnode);
    ASSERT_ALWAYS(hub_v);
    hubinfo_get(hub_v, &hinfo);

    ASSERT(hinfo);
    ASSERT(hinfo->h_cnodeid == cnode);

    /* Select a possible interrupt target where there is a free interrupt
     * bit and also reserve the interrupt bit for this IO error interrupt
     */
    intr_cpu = intr_heuristic(hub_v,0,-1,0,hub_v,
			      "HUB IO error interrupt",&bit);
    if (intr_cpu == CPU_NONE) {
	printk("hubii_eint_init: intr_reserve_level failed, cnode %d", cnode);
	return;
    }
	
    rv = intr_connect_level(intr_cpu, bit, 0, NULL);
    request_irq(bit + (intr_cpu << 8), hubii_eint_handler, 0, "SN_hub_error", (void *)hub_v);
    irq_desc(bit + (intr_cpu << 8))->status |= SN2_IRQ_PER_HUB;
#ifdef BUS_INT_WAR                                              
    sn_add_polled_interrupt(bit + (intr_cpu << 8), (0.01 * HZ));
#endif
    ASSERT_ALWAYS(rv >= 0);
    hubio_eint.ii_iidsr_regval = 0;
    hubio_eint.ii_iidsr_fld_s.i_enable = 1;
    hubio_eint.ii_iidsr_fld_s.i_level = bit;/* Take the least significant bits*/
    hubio_eint.ii_iidsr_fld_s.i_node = COMPACT_TO_NASID_NODEID(cnode);
    hubio_eint.ii_iidsr_fld_s.i_pi_id = cpuid_to_subnode(intr_cpu);
    REMOTE_HUB_S(hinfo->h_nasid, IIO_IIDSR, hubio_eint.ii_iidsr_regval);

}


/*ARGSUSED*/
void
hubii_eint_handler (int irq, void *arg, struct pt_regs *ep)
{
    devfs_handle_t	hub_v;
    hubinfo_t		hinfo; 
    ii_wstat_u_t	wstat;
    hubreg_t		idsr;


    /* two levels of casting avoids compiler warning.!! */
    hub_v = (devfs_handle_t)(long)(arg); 
    ASSERT(hub_v);

    hubinfo_get(hub_v, &hinfo);
    
    /* 
     * Identify the reason for error. 
     */
    wstat.ii_wstat_regval = REMOTE_HUB_L(hinfo->h_nasid, IIO_WSTAT);

    if (wstat.ii_wstat_fld_s.w_crazy) {
	char	*reason;
	/*
	 * We can do a couple of things here. 
	 * Look at the fields TX_MX_RTY/XT_TAIL_TO/XT_CRD_TO to check
	 * which of these caused the CRAZY bit to be set. 
	 * You may be able to check if the Link is up really.
	 */
	if (wstat.ii_wstat_fld_s.w_tx_mx_rty)
		reason = "Micro Packet Retry Timeout";
	else if (wstat.ii_wstat_fld_s.w_xt_tail_to)
		reason = "Crosstalk Tail Timeout";
	else if (wstat.ii_wstat_fld_s.w_xt_crd_to)
		reason = "Crosstalk Credit Timeout";
	else {
		hubreg_t	hubii_imem;
		/*
		 * Check if widget 0 has been marked as shutdown, or
		 * if BTE 0/1 has been marked.
		 */
		hubii_imem = REMOTE_HUB_L(hinfo->h_nasid, IIO_IMEM);
		if (hubii_imem & IIO_IMEM_W0ESD)
			reason = "Hub Widget 0 has been Shutdown";
		else if (hubii_imem & IIO_IMEM_B0ESD)
			reason = "BTE 0 has been shutdown";
		else if (hubii_imem & IIO_IMEM_B1ESD)
			reason = "BTE 1 has been shutdown";
		else	reason = "Unknown";
	
	}
	/*
	 * Note: we may never be able to print this, if the II talking
	 * to Xbow which hosts the console is dead. 
	 */
	printk("Hub %d to Xtalk Link failed (II_ECRAZY) Reason: %s", 
		hinfo->h_cnodeid, reason);
    }

    /* 
     * It's a toss as to which one among PRB/CRB to check first. 
     * Current decision is based on the severity of the errors. 
     * IO CRB errors tend to be more severe than PRB errors.
     *
     * It is possible for BTE errors to have been handled already, so we
     * may not see any errors handled here. 
     */
    (void)hubiio_crb_error_handler(hub_v, hinfo);
    (void)hubiio_prb_error_handler(hub_v, hinfo);
    /*
     * If we reach here, it indicates crb/prb handlers successfully
     * handled the error. So, re-enable II to send more interrupt
     * and return.
     */
    REMOTE_HUB_S(hinfo->h_nasid, IIO_IECLR, 0xffffff);
    idsr = REMOTE_HUB_L(hinfo->h_nasid, IIO_IIDSR) & ~IIO_IIDSR_SENT_MASK;
    REMOTE_HUB_S(hinfo->h_nasid, IIO_IIDSR, idsr);
}

/*
 * Free the hub CRB "crbnum" which encountered an error.
 * Assumption is, error handling was successfully done,
 * and we now want to return the CRB back to Hub for normal usage.
 *
 * In order to free the CRB, all that's needed is to de-allocate it
 *
 * Assumption:
 *      No other processor is mucking around with the hub control register.
 *      So, upper layer has to single thread this.
 */
void
hubiio_crb_free(hubinfo_t hinfo, int crbnum)
{
	ii_icrb0_b_u_t         icrbb;

	/*
	* The hardware does NOT clear the mark bit, so it must get cleared
	* here to be sure the error is not processed twice.
	*/
	icrbb.ii_icrb0_b_regval = REMOTE_HUB_L(hinfo->h_nasid, IIO_ICRB_B(crbnum));
	icrbb.b_mark   = 0;
	REMOTE_HUB_S(hinfo->h_nasid, IIO_ICRB_B(crbnum), icrbb.ii_icrb0_b_regval);

	/*
	* Deallocate the register.
	*/

	REMOTE_HUB_S(hinfo->h_nasid, IIO_ICDR, (IIO_ICDR_PND | crbnum));

	/*
	* Wait till hub indicates it's done.
	*/
	while (REMOTE_HUB_L(hinfo->h_nasid, IIO_ICDR) & IIO_ICDR_PND)
		us_delay(1);

}


/*
 * Array of error names  that get logged in CRBs
 */ 
char *hubiio_crb_errors[] = {
	"Directory Error",
	"CRB Poison Error",
	"I/O Write Error",
	"I/O Access Error",
	"I/O Partial Write Error",
	"I/O Partial Read Error",
	"I/O Timeout Error",
	"Xtalk Error Packet"
};

/*
 * hubiio_crb_error_handler
 *
 *	This routine gets invoked when a hub gets an error 
 *	interrupt. So, the routine is running in interrupt context
 *	at error interrupt level.
 * Action:
 *	It's responsible for identifying ALL the CRBs that are marked
 *	with error, and process them. 
 *	
 * 	If you find the CRB that's marked with error, map this to the
 *	reason it caused error, and invoke appropriate error handler.
 *
 *	XXX Be aware of the information in the context register.
 *
 * NOTE:
 *	Use REMOTE_HUB_* macro instead of LOCAL_HUB_* so that the interrupt