hw/char/spapr_vty.c

   1 #include "hw/qdev.h"
   2 #include "sysemu/char.h"
   3 #include "hw/ppc/spapr.h"
   4 #include "hw/ppc/spapr_vio.h"
   5
   6 #define VTERM_BUFSIZE   16
   7
   8 typedef struct VIOsPAPRVTYDevice {
   9     VIOsPAPRDevice sdev;
  10     CharDriverState *chardev;
  11     uint32_t in, out;
  12     uint8_t buf[VTERM_BUFSIZE];
  13 } VIOsPAPRVTYDevice;
  14
  15 #define TYPE_VIO_SPAPR_VTY_DEVICE "spapr-vty"
  16 #define VIO_SPAPR_VTY_DEVICE(obj) \
  17      OBJECT_CHECK(VIOsPAPRVTYDevice, (obj), TYPE_VIO_SPAPR_VTY_DEVICE)
  18
  19 static int vty_can_receive(void *opaque)
  20 {
  21     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(opaque);
  22
  23     return (dev->in - dev->out) < VTERM_BUFSIZE;
  24 }
  25
  26 static void vty_receive(void *opaque, const uint8_t *buf, int size)
  27 {
  28     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(opaque);
  29     int i;
  30
  31     if ((dev->in == dev->out) && size) {
  32         /* toggle line to simulate edge interrupt */
  33         qemu_irq_pulse(spapr_vio_qirq(&dev->sdev));
  34     }
  35     for (i = 0; i < size; i++) {
  36         assert((dev->in - dev->out) < VTERM_BUFSIZE);
  37         dev->buf[dev->in++ % VTERM_BUFSIZE] = buf[i];
  38     }
  39 }
  40
  41 static int vty_getchars(VIOsPAPRDevice *sdev, uint8_t *buf, int max)
  42 {
  43     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(sdev);
  44     int n = 0;
  45
  46     while ((n < max) && (dev->out != dev->in)) {
  47         buf[n++] = dev->buf[dev->out++ % VTERM_BUFSIZE];
  48     }
  49
  50     return n;
  51 }
  52
  53 void vty_putchars(VIOsPAPRDevice *sdev, uint8_t *buf, int len)
  54 {
  55     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(sdev);
  56
  57     /* FIXME: should check the qemu_chr_fe_write() return value */
  58     qemu_chr_fe_write(dev->chardev, buf, len);
  59 }
  60
  61 static int spapr_vty_init(VIOsPAPRDevice *sdev)
  62 {
  63     VIOsPAPRVTYDevice *dev = VIO_SPAPR_VTY_DEVICE(sdev);
  64
  65     if (!dev->chardev) {
  66         fprintf(stderr, "spapr-vty: Can't create vty without a chardev!\n");
  67         exit(1);
  68     }
  69
  70     qemu_chr_add_handlers(dev->chardev, vty_can_receive,
  71                           vty_receive, NULL, dev);
  72
  73     return 0;
  74 }
  75
  76 /* Forward declaration */
  77 static target_ulong h_put_term_char(PowerPCCPU *cpu, sPAPREnvironment *spapr,
  78                                     target_ulong opcode, target_ulong *args)
  79 {
  80     target_ulong reg = args[0];
  81     target_ulong len = args[1];
  82     target_ulong char0_7 = args[2];
  83     target_ulong char8_15 = args[3];
  84     VIOsPAPRDevice *sdev;
  85     uint8_t buf[16];
  86
  87     sdev = vty_lookup(spapr, reg);
  88     if (!sdev) {
  89         return H_PARAMETER;
  90     }
  91
  92     if (len > 16) {
  93         return H_PARAMETER;
  94     }
  95
  96     *((uint64_t *)buf) = cpu_to_be64(char0_7);
  97     *((uint64_t *)buf + 1) = cpu_to_be64(char8_15);
  98
  99     vty_putchars(sdev, buf, len);
 100
 101     return H_SUCCESS;
 102 }
 103
 104 static target_ulong h_get_term_char(PowerPCCPU *cpu, sPAPREnvironment *spapr,
 105                                     target_ulong opcode, target_ulong *args)
 106 {
 107     target_ulong reg = args[0];
 108     target_ulong *len = args + 0;
 109     target_ulong *char0_7 = args + 1;
 110     target_ulong *char8_15 = args + 2;
 111     VIOsPAPRDevice *sdev;
 112     uint8_t buf[16];
 113
 114     sdev = vty_lookup(spapr, reg);
 115     if (!sdev) {
 116         return H_PARAMETER;
 117     }
 118
 119     *len = vty_getchars(sdev, buf, sizeof(buf));
 120     if (*len < 16) {
 121         memset(buf + *len, 0, 16 - *len);
 122     }
 123
 124     *char0_7 = be64_to_cpu(*((uint64_t *)buf));
 125     *char8_15 = be64_to_cpu(*((uint64_t *)buf + 1));
 126
 127     return H_SUCCESS;
 128 }
 129
 130 void spapr_vty_create(VIOsPAPRBus *bus, CharDriverState *chardev)
 131 {
 132     DeviceState *dev;
 133
 134     dev = qdev_create(&bus->bus, "spapr-vty");
 135     qdev_prop_set_chr(dev, "chardev", chardev);
 136     qdev_init_nofail(dev);
 137 }
 138
 139 static Property spapr_vty_properties[] = {
 140     DEFINE_SPAPR_PROPERTIES(VIOsPAPRVTYDevice, sdev),
 141     DEFINE_PROP_CHR("chardev", VIOsPAPRVTYDevice, chardev),
 142     DEFINE_PROP_END_OF_LIST(),
 143 };
 144
 145 static void spapr_vty_class_init(ObjectClass *klass, void *data)
 146 {
 147     DeviceClass *dc = DEVICE_CLASS(klass);
 148     VIOsPAPRDeviceClass *k = VIO_SPAPR_DEVICE_CLASS(klass);
 149
 150     k->init = spapr_vty_init;
 151     k->dt_name = "vty";
 152     k->dt_type = "serial";
 153     k->dt_compatible = "hvterm1";
 154     dc->props = spapr_vty_properties;
 155 }
 156
 157 static const TypeInfo spapr_vty_info = {
 158     .name          = TYPE_VIO_SPAPR_VTY_DEVICE,
 159     .parent        = TYPE_VIO_SPAPR_DEVICE,
 160     .instance_size = sizeof(VIOsPAPRVTYDevice),
 161     .class_init    = spapr_vty_class_init,
 162 };
 163
 164 VIOsPAPRDevice *spapr_vty_get_default(VIOsPAPRBus *bus)
 165 {
 166     VIOsPAPRDevice *sdev, *selected;
 167     BusChild *kid;
 168
 169     /*
 170      * To avoid the console bouncing around we want one VTY to be
 171      * the "default". We haven't really got anything to go on, so
 172      * arbitrarily choose the one with the lowest reg value.
 173      */
 174
 175     selected = NULL;
 176     QTAILQ_FOREACH(kid, &bus->bus.children, sibling) {
 177         DeviceState *iter = kid->child;
 178
 179         /* Only look at VTY devices */
 180         if (!object_dynamic_cast(OBJECT(iter), "spapr-vty")) {
 181             continue;
 182         }
 183
 184         sdev = VIO_SPAPR_DEVICE(iter);
 185
 186         /* First VTY we've found, so it is selected for now */
 187         if (!selected) {
 188             selected = sdev;
 189             continue;
 190         }
 191
 192         /* Choose VTY with lowest reg value */
 193         if (sdev->reg < selected->reg) {
 194             selected = sdev;
 195         }
 196     }
 197
 198     return selected;
 199 }
 200
 201 VIOsPAPRDevice *vty_lookup(sPAPREnvironment *spapr, target_ulong reg)
 202 {
 203     VIOsPAPRDevice *sdev;
 204
 205     sdev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
 206     if (!sdev && reg == 0) {
 207         /* Hack for kernel early debug, which always specifies reg==0.
 208          * We search all VIO devices, and grab the vty with the lowest
 209          * reg.  This attempts to mimic existing PowerVM behaviour
 210          * (early debug does work there, despite having no vty with
 211          * reg==0. */
 212         return spapr_vty_get_default(spapr->vio_bus);
 213     }
 214
 215     return sdev;
 216 }
 217
 218 static void spapr_vty_register_types(void)
 219 {
 220     spapr_register_hypercall(H_PUT_TERM_CHAR, h_put_term_char);
 221     spapr_register_hypercall(H_GET_TERM_CHAR, h_get_term_char);
 222     type_register_static(&spapr_vty_info);
 223 }
 224
 225 type_init(spapr_vty_register_types)