Commit c1755b14 authored by Halil Pasic's avatar Halil Pasic Committed by Cornelia Huck
Browse files

s390x/css: clear IO irqs when generating IPI CRW 



According to the Principles of Operation (more precisely the subsection
'Channel-Report Word'), a subchannel put into the installed parameters
initialized state is in the same state as after an I/O system reset (just
parameters possibly changed). This implies that any I/O interrupts for that
subchannel are no longer pending (as I/O system resets clear I/O
interrupts). Therefore, we need an interface to clear pending I/O
interrupts. Make css_generate_sch_crws clear the pending IO interrupts for
the subchannel.

Signed-off-by: default avatarHalil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent 9eccb862

hw/s390x/css.c

+40 −3
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
 */



#include "qemu/osdep.h"

#include "qapi/error.h"

#include <hw/qdev.h>

#include "qemu/bitops.h"

#include "exec/address-spaces.h"
@@ -192,12 +193,46 @@ out: 
    return ret;

}



uint16_t css_build_subchannel_id(SubchDev *sch)

static void css_clear_io_interrupt(uint16_t subchannel_id,

                                   uint16_t subchannel_nr)

{

    Error *err = NULL;

    static bool no_clear_irq;

    S390FLICState *fs = s390_get_flic();

    S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);

    int r;



    if (unlikely(no_clear_irq)) {

        return;

    }

    r = fsc->clear_io_irq(fs, subchannel_id, subchannel_nr);

    switch (r) {

    case 0:

        break;

    case -ENOSYS:

        no_clear_irq = true;

        /*

        * Ignore unavailability, as the user can't do anything

        * about it anyway.

        */

        break;

    default:

        error_setg_errno(&err, -r, "unexpected error condition");

        error_propagate(&error_abort, err);

    }

}



static inline uint16_t css_do_build_subchannel_id(uint8_t cssid, uint8_t ssid)

{

    if (channel_subsys.max_cssid > 0) {

        return (sch->cssid << 8) | (1 << 3) | (sch->ssid << 1) | 1;

        return (cssid << 8) | (1 << 3) | (ssid << 1) | 1;

    }

    return (ssid << 1) | 1;

}

    return (sch->ssid << 1) | 1;



uint16_t css_build_subchannel_id(SubchDev *sch)

{

    return css_do_build_subchannel_id(sch->cssid, sch->ssid);

}



static void css_inject_io_interrupt(SubchDev *sch)
@@ -1429,6 +1464,8 @@ void css_generate_sch_crws(uint8_t cssid, uint8_t ssid, uint16_t schid, 
        css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, 0,

                      (guest_cssid << 8) | (ssid << 4));

    }

    /* RW_ERC_IPI --> clear pending interrupts */

    css_clear_io_interrupt(css_do_build_subchannel_id(cssid, ssid), schid);

}



void css_generate_chp_crws(uint8_t cssid, uint8_t chpid)