hw/char/spapr_vty.c

   1 #include "qemu/osdep.h"
   2 #include "qapi/error.h"
   3 #include "qemu-common.h"
   4 #include "cpu.h"
   5 #include "hw/qdev.h"
   6 #include "sysemu/char.h"
   7 #include "hw/ppc/spapr.h"
   8 #include "hw/ppc/spapr_vio.h"
   9
  10 #define VTERM_BUFSIZE   16
  11
  12 typedef struct VIOsPAPRVTYDevice {
  13     VIOsPAPRDevice sdev;
  14     CharDriverState *chardev;
  15     uint32_t in, out;
  16     uint8_t buf[VTERM_BUFSIZE];
  17 } VIOsPAPRVTYDevice;
  18
  19 #define TYPE_VIO_SPAPR_VTY_DEVICE "spapr-vty"
  20 #define VIO_SPAPR_VTY_DEVICE(obj) \
  21      OBJECT_CHECK(VIOsPAPRVTYDevice, (obj), TYPE_VIO_SPAPR_VTY_DEVICE)
  22
  23 static int vty_can_receive(void *opaque)
  24 {
  25     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(opaque);
  26
  27     return (dev->in - dev->out) < VTERM_BUFSIZE;
  28 }
  29
  30 static void vty_receive(void *opaque, const uint8_t *buf, int size)
  31 {
  32     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(opaque);
  33     int i;
  34
  35     if ((dev->in == dev->out) && size) {
  36         /* toggle line to simulate edge interrupt */
  37         qemu_irq_pulse(spapr_vio_qirq(&dev->sdev));
  38     }
  39     for (i = 0; i < size; i++) {
  40         assert((dev->in - dev->out) < VTERM_BUFSIZE);
  41         dev->buf[dev->in++ % VTERM_BUFSIZE] = buf[i];
  42     }
  43 }
  44
  45 static int vty_getchars(VIOsPAPRDevice *sdev, uint8_t *buf, int max)
  46 {
  47     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(sdev);
  48     int n = 0;
  49
  50     while ((n < max) && (dev->out != dev->in)) {
  51         buf[n++] = dev->buf[dev->out++ % VTERM_BUFSIZE];
  52     }
  53
  54     qemu_chr_accept_input(dev->chardev);
  55
  56     return n;
  57 }
  58
  59 void vty_putchars(VIOsPAPRDevice *sdev, uint8_t *buf, int len)
  60 {
  61     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(sdev);
  62
  63     /* FIXME: should check the qemu_chr_fe_write() return value */
  64     qemu_chr_fe_write(dev->chardev, buf, len);
  65 }
  66
  67 static void spapr_vty_realize(VIOsPAPRDevice *sdev, Error **errp)
  68 {
  69     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(sdev);
  70
  71     if (!dev->chardev) {
  72         error_setg(errp, "chardev property not set");
  73         return;
  74     }
  75
  76     qemu_chr_add_handlers(dev->chardev, vty_can_receive,
  77                           vty_receive, NULL, dev);
  78 }
  79
  80 /* Forward declaration */
  81 static target_ulong h_put_term_char(PowerPCCPU *cpu, sPAPRMachineState *spapr,
  82                                     target_ulong opcode, target_ulong *args)
  83 {
  84     target_ulong reg = args[0];
  85     target_ulong len = args[1];
  86     target_ulong char0_7 = args[2];
  87     target_ulong char8_15 = args[3];
  88     VIOsPAPRDevice *sdev;
  89     uint8_t buf[16];
  90
  91     sdev = vty_lookup(spapr, reg);
  92     if (!sdev) {
  93         return H_PARAMETER;
  94     }
  95
  96     if (len > 16) {
  97         return H_PARAMETER;
  98     }
  99
 100     *((uint64_t *)buf) = cpu_to_be64(char0_7);
 101     *((uint64_t *)buf + 1) = cpu_to_be64(char8_15);
 102
 103     vty_putchars(sdev, buf, len);
 104
 105     return H_SUCCESS;
 106 }
 107
 108 static target_ulong h_get_term_char(PowerPCCPU *cpu, sPAPRMachineState *spapr,
 109                                     target_ulong opcode, target_ulong *args)
 110 {
 111     target_ulong reg = args[0];
 112     target_ulong *len = args + 0;
 113     target_ulong *char0_7 = args + 1;
 114     target_ulong *char8_15 = args + 2;
 115     VIOsPAPRDevice *sdev;
 116     uint8_t buf[16];
 117
 118     sdev = vty_lookup(spapr, reg);
 119     if (!sdev) {
 120         return H_PARAMETER;
 121     }
 122
 123     *len = vty_getchars(sdev, buf, sizeof(buf));
 124     if (*len < 16) {
 125         memset(buf + *len, 0, 16 - *len);
 126     }
 127
 128     *char0_7 = be64_to_cpu(*((uint64_t *)buf));
 129     *char8_15 = be64_to_cpu(*((uint64_t *)buf + 1));
 130
 131     return H_SUCCESS;
 132 }
 133
 134 void spapr_vty_create(VIOsPAPRBus *bus, CharDriverState *chardev)
 135 {
 136     DeviceState *dev;
 137
 138     dev = qdev_create(&bus->bus, "spapr-vty");
 139     qdev_prop_set_chr(dev, "chardev", chardev);
 140     qdev_init_nofail(dev);
 141 }
 142
 143 static Property spapr_vty_properties[] = {
 144     DEFINE_SPAPR_PROPERTIES(VIOsPAPRVTYDevice, sdev),
 145     DEFINE_PROP_CHR("chardev", VIOsPAPRVTYDevice, chardev),
 146     DEFINE_PROP_END_OF_LIST(),
 147 };
 148
 149 static const VMStateDescription vmstate_spapr_vty = {
 150     .name = "spapr_vty",
 151     .version_id = 1,
 152     .minimum_version_id = 1,
 153     .fields = (VMStateField[]) {
 154         VMSTATE_SPAPR_VIO(sdev, VIOsPAPRVTYDevice),
 155
 156         VMSTATE_UINT32(in, VIOsPAPRVTYDevice),
 157         VMSTATE_UINT32(out, VIOsPAPRVTYDevice),
 158         VMSTATE_BUFFER(buf, VIOsPAPRVTYDevice),
 159         VMSTATE_END_OF_LIST()
 160     },
 161 };
 162
 163 static void spapr_vty_class_init(ObjectClass *klass, void *data)
 164 {
 165     DeviceClass *dc = DEVICE_CLASS(klass);
 166     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
 167
 168     k->realize = spapr_vty_realize;
 169     k->dt_name = "vty";
 170     k->dt_type = "serial";
 171     k->dt_compatible = "hvterm1";
 172     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
 173     dc->props = spapr_vty_properties;
 174     dc->vmsd = &vmstate_spapr_vty;
 175 }
 176
 177 static const TypeInfo spapr_vty_info = {
 178     .name          = TYPE_VIO_SPAPR_VTY_DEVICE,
 179     .parent        = TYPE_VIO_SPAPR_DEVICE,
 180     .instance_size = sizeof(VIOsPAPRVTYDevice),
 181     .class_init    = spapr_vty_class_init,
 182 };
 183
 184 VIOsPAPRDevice *spapr_vty_get_default(VIOsPAPRBus *bus)
 185 {
 186     VIOsPAPRDevice *sdev, *selected;
 187     BusChild *kid;
 188
 189     /*
 190      * To avoid the console bouncing around we want one VTY to be
 191      * the "default". We haven't really got anything to go on, so
 192      * arbitrarily choose the one with the lowest reg value.
 193      */
 194
 195     selected = NULL;
 196     QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
 197         DeviceState *iter = kid->child;
 198
 199         /* Only look at VTY devices */
 200         if (!object_dynamic_cast(OBJECT(iter), TYPE_VIO_SPAPR_VTY_DEVICE)) {
 201             continue;
 202         }
 203
 204         sdev = VIO_SPAPR_DEVICE(iter);
 205
 206         /* First VTY we've found, so it is selected for now */
 207         if (!selected) {
 208             selected = sdev;
 209             continue;
 210         }
 211
 212         /* Choose VTY with lowest reg value */
 213         if (sdev->reg < selected->reg) {
 214             selected = sdev;
 215         }
 216     }
 217
 218     return selected;
 219 }
 220
 221 VIOsPAPRDevice *vty_lookup(sPAPRMachineState *spapr, target_ulong reg)
 222 {
 223     VIOsPAPRDevice *sdev;
 224
 225     sdev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
 226     if (!sdev && reg == 0) {
 227         /* Hack for kernel early debug, which always specifies reg==0.
 228          * We search all VIO devices, and grab the vty with the lowest
 229          * reg.  This attempts to mimic existing PowerVM behaviour
 230          * (early debug does work there, despite having no vty with
 231          * reg==0. */
 232         return spapr_vty_get_default(spapr->vio_bus);
 233     }
 234
 235     if (!object_dynamic_cast(OBJECT(sdev), TYPE_VIO_SPAPR_VTY_DEVICE)) {
 236         return NULL;
 237     }
 238
 239     return sdev;
 240 }
 241
 242 static void spapr_vty_register_types(void)
 243 {
 244     spapr_register_hypercall(H_PUT_TERM_CHAR, h_put_term_char);
 245     spapr_register_hypercall(H_GET_TERM_CHAR, h_get_term_char);
 246     type_register_static(&spapr_vty_info);
 247 }
 248
 249 type_init(spapr_vty_register_types)