The PONG device accept two commands: PONG_READ and PONG_WRITE which allow to read from and write to an internal buffer of 1024 bytes.
The QEMU device is named ccw-pong. Signed-off-by: Pierre Morel <pmo...@linux.ibm.com> --- hw/s390x/Makefile.objs | 1 + hw/s390x/ccw-pong.c | 186 ++++++++++++++++++++++++++++++++++++++++++++++++ include/hw/s390x/pong.h | 47 ++++++++++++ 3 files changed, 234 insertions(+) create mode 100644 hw/s390x/ccw-pong.c create mode 100644 include/hw/s390x/pong.h diff --git a/hw/s390x/Makefile.objs b/hw/s390x/Makefile.objs index ee91152..3a83438 100644 --- a/hw/s390x/Makefile.objs +++ b/hw/s390x/Makefile.objs @@ -32,6 +32,7 @@ obj-$(CONFIG_KVM) += tod-kvm.o obj-$(CONFIG_KVM) += s390-skeys-kvm.o obj-$(CONFIG_KVM) += s390-stattrib-kvm.o s390-mchk.o obj-y += s390-ccw.o +obj-y += ccw-pong.o obj-y += ap-device.o obj-y += ap-bridge.o obj-y += s390-sei.o diff --git a/hw/s390x/ccw-pong.c b/hw/s390x/ccw-pong.c new file mode 100644 index 0000000..e7439d5 --- /dev/null +++ b/hw/s390x/ccw-pong.c @@ -0,0 +1,186 @@ +/* + * CCW PING-PONG + * + * Copyright 2019 IBM Corp. + * Author(s): Pierre Morel <pmo...@linux.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or (at + * your option) any later version. See the COPYING file in the top-level + * directory. + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "qemu/module.h" +#include "cpu.h" +#include "exec/address-spaces.h" +#include "hw/s390x/css.h" +#include "hw/s390x/css-bridge.h" +#include "hw/qdev-properties.h" +#include "hw/s390x/pong.h" + +#define PONG_BUF_SIZE 0x1000 +static char buf[PONG_BUF_SIZE] = "Hello world\n"; + +static inline int pong_rw(CCW1 *ccw, char *p, int len, bool dir) +{ + int ret; + + ret = address_space_rw(&address_space_memory, ccw->cda, + MEMTXATTRS_UNSPECIFIED, + (unsigned char *)buf, len, dir); + + return (ret == MEMTX_OK) ? -EIO : 0; +} + +/* Handle READ ccw commands from guest */ +static int handle_payload_read(CcwPONGDevice *dev, CCW1 *ccw) +{ + CcwDevice *ccw_dev = CCW_DEVICE(dev); + int len; + + if (!ccw->cda) { + return -EFAULT; + } + + if (ccw->count > PONG_BUF_SIZE) { + len = PONG_BUF_SIZE; + ccw_dev->sch->curr_status.scsw.count = ccw->count - PONG_BUF_SIZE; + } else { + len = ccw->count; + ccw_dev->sch->curr_status.scsw.count = 0; + } + + return pong_rw(ccw, buf, len, 1); +} + +/* + * Handle WRITE ccw commands to write data to client + * The SCSW count is set to the number of bytes not transfered. + */ +static int handle_payload_write(CcwPONGDevice *dev, CCW1 *ccw) +{ + CcwDevice *ccw_dev = CCW_DEVICE(dev); + int len; + + if (!ccw->cda) { + ccw_dev->sch->curr_status.scsw.count = ccw->count; + return -EFAULT; + } + + if (ccw->count > PONG_BUF_SIZE) { + len = PONG_BUF_SIZE; + ccw_dev->sch->curr_status.scsw.count = ccw->count - PONG_BUF_SIZE; + } else { + len = ccw->count; + ccw_dev->sch->curr_status.scsw.count = 0; + } + + return pong_rw(ccw, buf, len, 0); +} + +static int pong_ccw_cb(SubchDev *sch, CCW1 ccw) +{ + int rc = 0; + CcwPONGDevice *dev = sch->driver_data; + + switch (ccw.cmd_code) { + case PONG_WRITE: + rc = handle_payload_write(dev, &ccw); + break; + case PONG_READ: + rc = handle_payload_read(dev, &ccw); + break; + default: + rc = -ENOSYS; + break; + } + + if (rc == -EIO) { + /* I/O error, specific devices generate specific conditions */ + SCHIB *schib = &sch->curr_status; + + sch->curr_status.scsw.dstat = SCSW_DSTAT_UNIT_CHECK; + sch->sense_data[0] = 0x40; /* intervention-req */ + schib->scsw.ctrl &= ~SCSW_ACTL_START_PEND; + schib->scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL; + schib->scsw.ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY | + SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; + } + return rc; +} + +static void pong_ccw_realize(DeviceState *ds, Error **errp) +{ + uint16_t chpid; + CcwPONGDevice *dev = CCW_PONG(ds); + CcwDevice *cdev = CCW_DEVICE(ds); + CCWDeviceClass *cdk = CCW_DEVICE_GET_CLASS(cdev); + SubchDev *sch; + Error *err = NULL; + + sch = css_create_sch(cdev->devno, errp); + if (!sch) { + return; + } + + sch->driver_data = dev; + cdev->sch = sch; + chpid = css_find_free_chpid(sch->cssid); + + if (chpid > MAX_CHPID) { + error_setg(&err, "No available chpid to use."); + goto out_err; + } + + sch->id.reserved = 0xff; + sch->id.cu_type = CCW_PONG_CU_TYPE; + css_sch_build_virtual_schib(sch, (uint8_t)chpid, + CCW_PONG_CHPID_TYPE); + sch->do_subchannel_work = do_subchannel_work_virtual; + sch->ccw_cb = pong_ccw_cb; + + cdk->realize(cdev, &err); + if (err) { + goto out_err; + } + + css_reset_sch(sch); + return; + +out_err: + error_propagate(errp, err); + css_subch_assign(sch->cssid, sch->ssid, sch->schid, sch->devno, NULL); + cdev->sch = NULL; + g_free(sch); +} + +static Property pong_ccw_properties[] = { + DEFINE_PROP_END_OF_LIST(), +}; + +static void pong_ccw_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->props = pong_ccw_properties; + dc->bus_type = TYPE_VIRTUAL_CSS_BUS; + dc->realize = pong_ccw_realize; + dc->hotpluggable = false; + set_bit(DEVICE_CATEGORY_DISPLAY, dc->categories); +} + +static const TypeInfo pong_ccw_info = { + .name = TYPE_CCW_PONG, + .parent = TYPE_CCW_DEVICE, + .instance_size = sizeof(CcwPONGDevice), + .class_init = pong_ccw_class_init, + .class_size = sizeof(CcwPONGClass), +}; + +static void pong_ccw_register(void) +{ + type_register_static(&pong_ccw_info); +} + +type_init(pong_ccw_register) diff --git a/include/hw/s390x/pong.h b/include/hw/s390x/pong.h new file mode 100644 index 0000000..6358e2d --- /dev/null +++ b/include/hw/s390x/pong.h @@ -0,0 +1,47 @@ +/* + * ccw-attached PONG definitions + * + * Copyright 2019 IBM Corp. + * Author(s): Pierre Morel <pmo...@linux.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or (at + * your option) any later version. See the COPYING file in the top-level + * directory. + */ + +#ifndef HW_S390X_PONG_CCW_H +#define HW_S390X_PONG_CCW_H + +#include "hw/sysbus.h" +#include "hw/s390x/css.h" +#include "hw/s390x/ccw-device.h" + +#define CCW_PONG_CU_TYPE 0x0007 +#define CCW_PONG_CHPID_TYPE 0x09 + +#define TYPE_CCW_PONG "ccw-pong" + +/* Local Channel Commands */ +#define PONG_WRITE 0x21 /* Write */ +#define PONG_READ 0x22 /* Read buffer */ + +#define CCW_PONG(obj) \ + OBJECT_CHECK(CcwPONGDevice, (obj), TYPE_CCW_PONG) +#define CCW_PONG_CLASS(klass) \ + OBJECT_CLASS_CHECK(CcwPONGClass, (klass), TYPE_CCW_PONG) +#define CCW_PONG_GET_CLASS(obj) \ + OBJECT_GET_CLASS(CcwPONGClass, (obj), TYPE_CCW_PONG) + +typedef struct CcwPONGDevice { + CcwDevice parent_obj; +} CcwPONGDevice; + +typedef struct CcwPONGClass { + CCWDeviceClass parent_class; + + void (*init)(CcwPONGDevice *, Error **); + int (*read_payload)(CcwPONGDevice *); + int (*write_payload)(CcwPONGDevice *, uint8_t); +} CcwPONGClass; + +#endif -- 2.7.4