Commit 59efbff1 authored by Thomas Huth's avatar Thomas Huth Committed by Christian Borntraeger
Browse files

pc-bios/s390-ccw: Add code for virtio feature negotiation 



The upcoming virtio-net driver needs to negotiate some features,
so we need the possibility to do this in the core virtio code.

Reviewed-by: default avatarCornelia Huck <cohuck@redhat.com>
Signed-off-by: default avatarThomas Huth <thuth@redhat.com>
Message-Id: <1499863793-18627-8-git-send-email-thuth@redhat.com>
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
parent ac7bec7c

pc-bios/s390-ccw/s390-ccw.h

+2 −0
Original line number Diff line number Diff line
@@ -44,6 +44,8 @@ typedef unsigned long long __u64; 
                            ((b) == 0 ? (a) : (MIN(a, b))))

#endif



#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))



#include "cio.h"

#include "iplb.h"

pc-bios/s390-ccw/virtio.c

+17 −6
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include "s390-ccw.h"

#include "virtio.h"

#include "virtio-scsi.h"

#include "bswap.h"



#define VRING_WAIT_REPLY_TIMEOUT 3
@@ -249,8 +250,12 @@ int virtio_run(VDev *vdev, int vqid, VirtioCmd *cmd) 


void virtio_setup_ccw(VDev *vdev)

{

    int i, cfg_size = 0;

    int i, rc, cfg_size = 0;

    unsigned char status = VIRTIO_CONFIG_S_DRIVER_OK;

    struct VirtioFeatureDesc {

        uint32_t features;

        uint8_t index;

    } __attribute__((packed)) feats;



    IPL_assert(virtio_is_supported(vdev->schid), "PE");

    /* device ID has been established now */
@@ -277,11 +282,17 @@ void virtio_setup_ccw(VDev *vdev) 
    IPL_assert(run_ccw(vdev, CCW_CMD_READ_CONF, &vdev->config, cfg_size) == 0,

               "Could not get block device configuration");



    /*

     * Skipping CCW_CMD_READ_FEAT. We're not doing anything fancy, and

     * we'll just stop dead anyway if anything does not work like we

     * expect it.

     */

    /* Feature negotiation */

    for (i = 0; i < ARRAY_SIZE(vdev->guest_features); i++) {

        feats.features = 0;

        feats.index = i;

        rc = run_ccw(vdev, CCW_CMD_READ_FEAT, &feats, sizeof(feats));

        IPL_assert(rc == 0, "Could not get features bits");

        vdev->guest_features[i] &= bswap32(feats.features);

        feats.features = bswap32(vdev->guest_features[i]);

        rc = run_ccw(vdev, CCW_CMD_WRITE_FEAT, &feats, sizeof(feats));

        IPL_assert(rc == 0, "Could not set features bits");

    }



    for (i = 0; i < vdev->nr_vqs; i++) {

        VqInfo info = {

pc-bios/s390-ccw/virtio.h

+1 −0
Original line number Diff line number Diff line
@@ -251,6 +251,7 @@ struct VDev { 
    ScsiDevice selected_scsi_device;

    uint64_t netboot_start_addr;

    uint32_t max_transfer;

    uint32_t guest_features[2];

};

typedef struct VDev VDev;