Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 1 | /* |
| 2 | * QEMU model of Xilinx uartlite. |
| 3 | * |
| 4 | * Copyright (c) 2009 Edgar E. Iglesias. |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 22 | * THE SOFTWARE. |
| 23 | */ |
| 24 | |
| 25 | #include "sysbus.h" |
| 26 | #include "qemu-char.h" |
| 27 | |
| 28 | #define DUART(x) |
| 29 | |
| 30 | #define R_RX 0 |
| 31 | #define R_TX 1 |
| 32 | #define R_STATUS 2 |
| 33 | #define R_CTRL 3 |
| 34 | #define R_MAX 4 |
| 35 | |
| 36 | #define STATUS_RXVALID 0x01 |
| 37 | #define STATUS_RXFULL 0x02 |
| 38 | #define STATUS_TXEMPTY 0x04 |
| 39 | #define STATUS_TXFULL 0x08 |
| 40 | #define STATUS_IE 0x10 |
| 41 | #define STATUS_OVERRUN 0x20 |
| 42 | #define STATUS_FRAME 0x40 |
| 43 | #define STATUS_PARITY 0x80 |
| 44 | |
| 45 | #define CONTROL_RST_TX 0x01 |
| 46 | #define CONTROL_RST_RX 0x02 |
| 47 | #define CONTROL_IE 0x10 |
| 48 | |
| 49 | struct xlx_uartlite |
| 50 | { |
| 51 | SysBusDevice busdev; |
Edgar E. Iglesias | 010f3f5 | 2011-08-26 00:13:47 +0200 | [diff] [blame] | 52 | MemoryRegion mmio; |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 53 | CharDriverState *chr; |
| 54 | qemu_irq irq; |
| 55 | |
| 56 | uint8_t rx_fifo[8]; |
| 57 | unsigned int rx_fifo_pos; |
| 58 | unsigned int rx_fifo_len; |
| 59 | |
| 60 | uint32_t regs[R_MAX]; |
| 61 | }; |
| 62 | |
| 63 | static void uart_update_irq(struct xlx_uartlite *s) |
| 64 | { |
| 65 | unsigned int irq; |
| 66 | |
| 67 | if (s->rx_fifo_len) |
| 68 | s->regs[R_STATUS] |= STATUS_IE; |
| 69 | |
| 70 | irq = (s->regs[R_STATUS] & STATUS_IE) && (s->regs[R_CTRL] & CONTROL_IE); |
| 71 | qemu_set_irq(s->irq, irq); |
| 72 | } |
| 73 | |
| 74 | static void uart_update_status(struct xlx_uartlite *s) |
| 75 | { |
| 76 | uint32_t r; |
| 77 | |
| 78 | r = s->regs[R_STATUS]; |
| 79 | r &= ~7; |
| 80 | r |= 1 << 2; /* Tx fifo is always empty. We are fast :) */ |
| 81 | r |= (s->rx_fifo_len == sizeof (s->rx_fifo)) << 1; |
| 82 | r |= (!!s->rx_fifo_len); |
| 83 | s->regs[R_STATUS] = r; |
| 84 | } |
| 85 | |
Edgar E. Iglesias | 010f3f5 | 2011-08-26 00:13:47 +0200 | [diff] [blame] | 86 | static uint64_t |
| 87 | uart_read(void *opaque, target_phys_addr_t addr, unsigned int size) |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 88 | { |
| 89 | struct xlx_uartlite *s = opaque; |
| 90 | uint32_t r = 0; |
| 91 | addr >>= 2; |
| 92 | switch (addr) |
| 93 | { |
| 94 | case R_RX: |
| 95 | r = s->rx_fifo[(s->rx_fifo_pos - s->rx_fifo_len) & 7]; |
| 96 | if (s->rx_fifo_len) |
| 97 | s->rx_fifo_len--; |
| 98 | uart_update_status(s); |
| 99 | uart_update_irq(s); |
| 100 | break; |
| 101 | |
| 102 | default: |
| 103 | if (addr < ARRAY_SIZE(s->regs)) |
| 104 | r = s->regs[addr]; |
| 105 | DUART(qemu_log("%s addr=%x v=%x\n", __func__, addr, r)); |
| 106 | break; |
| 107 | } |
| 108 | return r; |
| 109 | } |
| 110 | |
| 111 | static void |
Edgar E. Iglesias | 010f3f5 | 2011-08-26 00:13:47 +0200 | [diff] [blame] | 112 | uart_write(void *opaque, target_phys_addr_t addr, |
| 113 | uint64_t val64, unsigned int size) |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 114 | { |
| 115 | struct xlx_uartlite *s = opaque; |
Edgar E. Iglesias | 010f3f5 | 2011-08-26 00:13:47 +0200 | [diff] [blame] | 116 | uint32_t value = val64; |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 117 | unsigned char ch = value; |
| 118 | |
| 119 | addr >>= 2; |
| 120 | switch (addr) |
| 121 | { |
| 122 | case R_STATUS: |
| 123 | hw_error("write to UART STATUS?\n"); |
| 124 | break; |
| 125 | |
| 126 | case R_CTRL: |
| 127 | if (value & CONTROL_RST_RX) { |
| 128 | s->rx_fifo_pos = 0; |
| 129 | s->rx_fifo_len = 0; |
| 130 | } |
| 131 | s->regs[addr] = value; |
| 132 | break; |
| 133 | |
| 134 | case R_TX: |
| 135 | if (s->chr) |
Anthony Liguori | 2cc6e0a | 2011-08-15 11:17:28 -0500 | [diff] [blame] | 136 | qemu_chr_fe_write(s->chr, &ch, 1); |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 137 | |
| 138 | s->regs[addr] = value; |
| 139 | |
| 140 | /* hax. */ |
| 141 | s->regs[R_STATUS] |= STATUS_IE; |
| 142 | break; |
| 143 | |
| 144 | default: |
| 145 | DUART(printf("%s addr=%x v=%x\n", __func__, addr, value)); |
| 146 | if (addr < ARRAY_SIZE(s->regs)) |
| 147 | s->regs[addr] = value; |
| 148 | break; |
| 149 | } |
| 150 | uart_update_status(s); |
| 151 | uart_update_irq(s); |
| 152 | } |
| 153 | |
Edgar E. Iglesias | 010f3f5 | 2011-08-26 00:13:47 +0200 | [diff] [blame] | 154 | static const MemoryRegionOps uart_ops = { |
| 155 | .read = uart_read, |
| 156 | .write = uart_write, |
| 157 | .endianness = DEVICE_NATIVE_ENDIAN, |
| 158 | .valid = { |
| 159 | .min_access_size = 1, |
| 160 | .max_access_size = 4 |
| 161 | } |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 162 | }; |
| 163 | |
| 164 | static void uart_rx(void *opaque, const uint8_t *buf, int size) |
| 165 | { |
| 166 | struct xlx_uartlite *s = opaque; |
| 167 | |
| 168 | /* Got a byte. */ |
| 169 | if (s->rx_fifo_len >= 8) { |
| 170 | printf("WARNING: UART dropped char.\n"); |
| 171 | return; |
| 172 | } |
| 173 | s->rx_fifo[s->rx_fifo_pos] = *buf; |
| 174 | s->rx_fifo_pos++; |
| 175 | s->rx_fifo_pos &= 0x7; |
| 176 | s->rx_fifo_len++; |
| 177 | |
| 178 | uart_update_status(s); |
| 179 | uart_update_irq(s); |
| 180 | } |
| 181 | |
| 182 | static int uart_can_rx(void *opaque) |
| 183 | { |
| 184 | struct xlx_uartlite *s = opaque; |
| 185 | int r; |
| 186 | |
| 187 | r = s->rx_fifo_len < sizeof(s->rx_fifo); |
| 188 | if (!r) |
| 189 | printf("cannot receive!\n"); |
| 190 | return r; |
| 191 | } |
| 192 | |
| 193 | static void uart_event(void *opaque, int event) |
| 194 | { |
| 195 | |
| 196 | } |
| 197 | |
Gerd Hoffmann | 81a322d | 2009-08-14 10:36:05 +0200 | [diff] [blame] | 198 | static int xilinx_uartlite_init(SysBusDevice *dev) |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 199 | { |
| 200 | struct xlx_uartlite *s = FROM_SYSBUS(typeof (*s), dev); |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 201 | |
| 202 | sysbus_init_irq(dev, &s->irq); |
| 203 | |
| 204 | uart_update_status(s); |
Peter A. G. Crosthwaite | 23d6055 | 2012-06-13 14:46:41 +1000 | [diff] [blame] | 205 | memory_region_init_io(&s->mmio, &uart_ops, s, "xlnx.xps-uartlite", |
| 206 | R_MAX * 4); |
Avi Kivity | 750ecd4 | 2011-11-27 11:38:10 +0200 | [diff] [blame] | 207 | sysbus_init_mmio(dev, &s->mmio); |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 208 | |
Anthony Liguori | 0beb494 | 2011-12-22 15:29:25 -0600 | [diff] [blame] | 209 | s->chr = qemu_char_get_next_serial(); |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 210 | if (s->chr) |
| 211 | qemu_chr_add_handlers(s->chr, uart_can_rx, uart_rx, uart_event, s); |
Gerd Hoffmann | 81a322d | 2009-08-14 10:36:05 +0200 | [diff] [blame] | 212 | return 0; |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 213 | } |
| 214 | |
Anthony Liguori | 999e12b | 2012-01-24 13:12:29 -0600 | [diff] [blame] | 215 | static void xilinx_uartlite_class_init(ObjectClass *klass, void *data) |
| 216 | { |
| 217 | SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass); |
| 218 | |
| 219 | sdc->init = xilinx_uartlite_init; |
| 220 | } |
| 221 | |
Anthony Liguori | 39bffca | 2011-12-07 21:34:16 -0600 | [diff] [blame] | 222 | static TypeInfo xilinx_uartlite_info = { |
Peter A. G. Crosthwaite | 23d6055 | 2012-06-13 14:46:41 +1000 | [diff] [blame] | 223 | .name = "xlnx.xps-uartlite", |
Anthony Liguori | 39bffca | 2011-12-07 21:34:16 -0600 | [diff] [blame] | 224 | .parent = TYPE_SYS_BUS_DEVICE, |
| 225 | .instance_size = sizeof (struct xlx_uartlite), |
| 226 | .class_init = xilinx_uartlite_class_init, |
Anthony Liguori | 999e12b | 2012-01-24 13:12:29 -0600 | [diff] [blame] | 227 | }; |
| 228 | |
Andreas Färber | 83f7d43 | 2012-02-09 15:20:55 +0100 | [diff] [blame] | 229 | static void xilinx_uart_register_types(void) |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 230 | { |
Anthony Liguori | 39bffca | 2011-12-07 21:34:16 -0600 | [diff] [blame] | 231 | type_register_static(&xilinx_uartlite_info); |
Edgar E. Iglesias | ee118d9 | 2009-05-20 20:12:42 +0200 | [diff] [blame] | 232 | } |
| 233 | |
Andreas Färber | 83f7d43 | 2012-02-09 15:20:55 +0100 | [diff] [blame] | 234 | type_init(xilinx_uart_register_types) |