hw/char/lm32_juart.c

   1 /*
   2  *  LatticeMico32 JTAG UART model.
   3  *
   4  *  Copyright (c) 2010 Michael Walle <michael@walle.cc>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu/osdep.h"
  21 #include "hw/sysbus.h"
  22 #include "migration/vmstate.h"
  23 #include "qemu/module.h"
  24 #include "trace.h"
  25 #include "chardev/char-fe.h"
  26
  27 #include "hw/char/lm32_juart.h"
  28 #include "hw/qdev-properties.h"
  29 #include "hw/qdev-properties-system.h"
  30 #include "qom/object.h"
  31
  32 enum {
  33     LM32_JUART_MIN_SAVE_VERSION = 0,
  34     LM32_JUART_CURRENT_SAVE_VERSION = 0,
  35     LM32_JUART_MAX_SAVE_VERSION = 0,
  36 };
  37
  38 enum {
  39     JTX_FULL = (1<<8),
  40 };
  41
  42 enum {
  43     JRX_FULL = (1<<8),
  44 };
  45
  46 OBJECT_DECLARE_SIMPLE_TYPE(LM32JuartState, LM32_JUART)
  47
  48 struct LM32JuartState {
  49     SysBusDevice parent_obj;
  50
  51     CharBackend chr;
  52
  53     uint32_t jtx;
  54     uint32_t jrx;
  55 };
  56
  57 uint32_t lm32_juart_get_jtx(DeviceState *d)
  58 {
  59     LM32JuartState *s = LM32_JUART(d);
  60
  61     trace_lm32_juart_get_jtx(s->jtx);
  62     return s->jtx;
  63 }
  64
  65 uint32_t lm32_juart_get_jrx(DeviceState *d)
  66 {
  67     LM32JuartState *s = LM32_JUART(d);
  68
  69     trace_lm32_juart_get_jrx(s->jrx);
  70     return s->jrx;
  71 }
  72
  73 void lm32_juart_set_jtx(DeviceState *d, uint32_t jtx)
  74 {
  75     LM32JuartState *s = LM32_JUART(d);
  76     unsigned char ch = jtx & 0xff;
  77
  78     trace_lm32_juart_set_jtx(s->jtx);
  79
  80     s->jtx = jtx;
  81     /* XXX this blocks entire thread. Rewrite to use
  82      * qemu_chr_fe_write and background I/O callbacks */
  83     qemu_chr_fe_write_all(&s->chr, &ch, 1);
  84 }
  85
  86 void lm32_juart_set_jrx(DeviceState *d, uint32_t jtx)
  87 {
  88     LM32JuartState *s = LM32_JUART(d);
  89
  90     trace_lm32_juart_set_jrx(s->jrx);
  91     s->jrx &= ~JRX_FULL;
  92 }
  93
  94 static void juart_rx(void *opaque, const uint8_t *buf, int size)
  95 {
  96     LM32JuartState *s = opaque;
  97
  98     s->jrx = *buf | JRX_FULL;
  99 }
 100
 101 static int juart_can_rx(void *opaque)
 102 {
 103     LM32JuartState *s = opaque;
 104
 105     return !(s->jrx & JRX_FULL);
 106 }
 107
 108 static void juart_event(void *opaque, QEMUChrEvent event)
 109 {
 110 }
 111
 112 static void juart_reset(DeviceState *d)
 113 {
 114     LM32JuartState *s = LM32_JUART(d);
 115
 116     s->jtx = 0;
 117     s->jrx = 0;
 118 }
 119
 120 static void lm32_juart_realize(DeviceState *dev, Error **errp)
 121 {
 122     LM32JuartState *s = LM32_JUART(dev);
 123
 124     qemu_chr_fe_set_handlers(&s->chr, juart_can_rx, juart_rx,
 125                              juart_event, NULL, s, NULL, true);
 126 }
 127
 128 static const VMStateDescription vmstate_lm32_juart = {
 129     .name = "lm32-juart",
 130     .version_id = 1,
 131     .minimum_version_id = 1,
 132     .fields = (VMStateField[]) {
 133         VMSTATE_UINT32(jtx, LM32JuartState),
 134         VMSTATE_UINT32(jrx, LM32JuartState),
 135         VMSTATE_END_OF_LIST()
 136     }
 137 };
 138
 139 static Property lm32_juart_properties[] = {
 140     DEFINE_PROP_CHR("chardev", LM32JuartState, chr),
 141     DEFINE_PROP_END_OF_LIST(),
 142 };
 143
 144 static void lm32_juart_class_init(ObjectClass *klass, void *data)
 145 {
 146     DeviceClass *dc = DEVICE_CLASS(klass);
 147
 148     dc->reset = juart_reset;
 149     dc->vmsd = &vmstate_lm32_juart;
 150     device_class_set_props(dc, lm32_juart_properties);
 151     dc->realize = lm32_juart_realize;
 152 }
 153
 154 static const TypeInfo lm32_juart_info = {
 155     .name          = TYPE_LM32_JUART,
 156     .parent        = TYPE_SYS_BUS_DEVICE,
 157     .instance_size = sizeof(LM32JuartState),
 158     .class_init    = lm32_juart_class_init,
 159 };
 160
 161 static void lm32_juart_register_types(void)
 162 {
 163     type_register_static(&lm32_juart_info);
 164 }
 165
 166 type_init(lm32_juart_register_types)