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     CharBackend 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_fe_accept_input(dev->chardev.chr);
  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     /* XXX this blocks entire thread. Rewrite to use
  64      * qemu_chr_fe_write and background I/O callbacks */
  65     qemu_chr_fe_write_all(dev->chardev.chr, buf, len);
  66 }
  67
  68 static void spapr_vty_realize(VIOsPAPRDevice *sdev, Error **errp)
  69 {
  70     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(sdev);
  71
  72     if (!dev->chardev.chr) {
  73         error_setg(errp, "chardev property not set");
  74         return;
  75     }
  76
  77     qemu_chr_add_handlers(dev->chardev.chr, vty_can_receive,
  78                           vty_receive, NULL, dev);
  79 }
  80
  81 /* Forward declaration */
  82 static target_ulong h_put_term_char(PowerPCCPU *cpu, sPAPRMachineState *spapr,
  83                                     target_ulong opcode, target_ulong *args)
  84 {
  85     target_ulong reg = args[0];
  86     target_ulong len = args[1];
  87     target_ulong char0_7 = args[2];
  88     target_ulong char8_15 = args[3];
  89     VIOsPAPRDevice *sdev;
  90     uint8_t buf[16];
  91
  92     sdev = vty_lookup(spapr, reg);
  93     if (!sdev) {
  94         return H_PARAMETER;
  95     }
  96
  97     if (len > 16) {
  98         return H_PARAMETER;
  99     }
 100
 101     *((uint64_t *)buf) = cpu_to_be64(char0_7);
 102     *((uint64_t *)buf + 1) = cpu_to_be64(char8_15);
 103
 104     vty_putchars(sdev, buf, len);
 105
 106     return H_SUCCESS;
 107 }
 108
 109 static target_ulong h_get_term_char(PowerPCCPU *cpu, sPAPRMachineState *spapr,
 110                                     target_ulong opcode, target_ulong *args)
 111 {
 112     target_ulong reg = args[0];
 113     target_ulong *len = args + 0;
 114     target_ulong *char0_7 = args + 1;
 115     target_ulong *char8_15 = args + 2;
 116     VIOsPAPRDevice *sdev;
 117     uint8_t buf[16];
 118
 119     sdev = vty_lookup(spapr, reg);
 120     if (!sdev) {
 121         return H_PARAMETER;
 122     }
 123
 124     *len = vty_getchars(sdev, buf, sizeof(buf));
 125     if (*len < 16) {
 126         memset(buf + *len, 0, 16 - *len);
 127     }
 128
 129     *char0_7 = be64_to_cpu(*((uint64_t *)buf));
 130     *char8_15 = be64_to_cpu(*((uint64_t *)buf + 1));
 131
 132     return H_SUCCESS;
 133 }
 134
 135 void spapr_vty_create(VIOsPAPRBus *bus, CharDriverState *chardev)
 136 {
 137     DeviceState *dev;
 138
 139     dev = qdev_create(&bus->bus, "spapr-vty");
 140     qdev_prop_set_chr(dev, "chardev", chardev);
 141     qdev_init_nofail(dev);
 142 }
 143
 144 static Property spapr_vty_properties[] = {
 145     DEFINE_SPAPR_PROPERTIES(VIOsPAPRVTYDevice, sdev),
 146     DEFINE_PROP_CHR("chardev", VIOsPAPRVTYDevice, chardev),
 147     DEFINE_PROP_END_OF_LIST(),
 148 };
 149
 150 static const VMStateDescription vmstate_spapr_vty = {
 151     .name = "spapr_vty",
 152     .version_id = 1,
 153     .minimum_version_id = 1,
 154     .fields = (VMStateField[]) {
 155         VMSTATE_SPAPR_VIO(sdev, VIOsPAPRVTYDevice),
 156
 157         VMSTATE_UINT32(in, VIOsPAPRVTYDevice),
 158         VMSTATE_UINT32(out, VIOsPAPRVTYDevice),
 159         VMSTATE_BUFFER(buf, VIOsPAPRVTYDevice),
 160         VMSTATE_END_OF_LIST()
 161     },
 162 };
 163
 164 static void spapr_vty_class_init(ObjectClass *klass, void *data)
 165 {
 166     DeviceClass *dc = DEVICE_CLASS(klass);
 167     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
 168
 169     k->realize = spapr_vty_realize;
 170     k->dt_name = "vty";
 171     k->dt_type = "serial";
 172     k->dt_compatible = "hvterm1";
 173     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
 174     dc->props = spapr_vty_properties;
 175     dc->vmsd = &vmstate_spapr_vty;
 176 }
 177
 178 static const TypeInfo spapr_vty_info = {
 179     .name          = TYPE_VIO_SPAPR_VTY_DEVICE,
 180     .parent        = TYPE_VIO_SPAPR_DEVICE,
 181     .instance_size = sizeof(VIOsPAPRVTYDevice),
 182     .class_init    = spapr_vty_class_init,
 183 };
 184
 185 VIOsPAPRDevice *spapr_vty_get_default(VIOsPAPRBus *bus)
 186 {
 187     VIOsPAPRDevice *sdev, *selected;
 188     BusChild *kid;
 189
 190     /*
 191      * To avoid the console bouncing around we want one VTY to be
 192      * the "default". We haven't really got anything to go on, so
 193      * arbitrarily choose the one with the lowest reg value.
 194      */
 195
 196     selected = NULL;
 197     QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
 198         DeviceState *iter = kid->child;
 199
 200         /* Only look at VTY devices */
 201         if (!object_dynamic_cast(OBJECT(iter), TYPE_VIO_SPAPR_VTY_DEVICE)) {
 202             continue;
 203         }
 204
 205         sdev = VIO_SPAPR_DEVICE(iter);
 206
 207         /* First VTY we've found, so it is selected for now */
 208         if (!selected) {
 209             selected = sdev;
 210             continue;
 211         }
 212
 213         /* Choose VTY with lowest reg value */
 214         if (sdev->reg < selected->reg) {
 215             selected = sdev;
 216         }
 217     }
 218
 219     return selected;
 220 }
 221
 222 VIOsPAPRDevice *vty_lookup(sPAPRMachineState *spapr, target_ulong reg)
 223 {
 224     VIOsPAPRDevice *sdev;
 225
 226     sdev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
 227     if (!sdev && reg == 0) {
 228         /* Hack for kernel early debug, which always specifies reg==0.
 229          * We search all VIO devices, and grab the vty with the lowest
 230          * reg.  This attempts to mimic existing PowerVM behaviour
 231          * (early debug does work there, despite having no vty with
 232          * reg==0. */
 233         return spapr_vty_get_default(spapr->vio_bus);
 234     }
 235
 236     if (!object_dynamic_cast(OBJECT(sdev), TYPE_VIO_SPAPR_VTY_DEVICE)) {
 237         return NULL;
 238     }
 239
 240     return sdev;
 241 }
 242
 243 static void spapr_vty_register_types(void)
 244 {
 245     spapr_register_hypercall(H_PUT_TERM_CHAR, h_put_term_char);
 246     spapr_register_hypercall(H_GET_TERM_CHAR, h_get_term_char);
 247     type_register_static(&spapr_vty_info);
 248 }
 249
 250 type_init(spapr_vty_register_types)