sim/bfin/dv-bfin_uart2.c

   1 /* Blackfin Universal Asynchronous Receiver/Transmitter (UART) model.
   2    For "new style" UARTs on BF50x/BF54x parts.
   3
   4    Copyright (C) 2010-2020 Free Software Foundation, Inc.
   5    Contributed by Analog Devices, Inc.
   6
   7    This file is part of simulators.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23
  24 #include "sim-main.h"
  25 #include "devices.h"
  26 #include "dv-bfin_uart2.h"
  27
  28 /* XXX: Should we bother emulating the TX/RX FIFOs ?  */
  29
  30 /* Internal state needs to be the same as bfin_uart.  */
  31 struct bfin_uart
  32 {
  33   /* This top portion matches common dv_bfin struct.  */
  34   bu32 base;
  35   struct hw *dma_master;
  36   bool acked;
  37
  38   struct hw_event *handler;
  39   char saved_byte;
  40   int saved_count;
  41
  42   /* Accessed indirectly by ier_{set,clear}.  */
  43   bu16 ier;
  44
  45   /* Order after here is important -- matches hardware MMR layout.  */
  46   bu16 BFIN_MMR_16(dll);
  47   bu16 BFIN_MMR_16(dlh);
  48   bu16 BFIN_MMR_16(gctl);
  49   bu16 BFIN_MMR_16(lcr);
  50   bu16 BFIN_MMR_16(mcr);
  51   bu16 BFIN_MMR_16(lsr);
  52   bu16 BFIN_MMR_16(msr);
  53   bu16 BFIN_MMR_16(scr);
  54   bu16 BFIN_MMR_16(ier_set);
  55   bu16 BFIN_MMR_16(ier_clear);
  56   bu16 BFIN_MMR_16(thr);
  57   bu16 BFIN_MMR_16(rbr);
  58 };
  59 #define mmr_base()      offsetof(struct bfin_uart, dll)
  60 #define mmr_offset(mmr) (offsetof(struct bfin_uart, mmr) - mmr_base())
  61
  62 static const char * const mmr_names[] =
  63 {
  64   "UART_DLL", "UART_DLH", "UART_GCTL", "UART_LCR", "UART_MCR", "UART_LSR",
  65   "UART_MSR", "UART_SCR", "UART_IER_SET", "UART_IER_CLEAR", "UART_THR",
  66   "UART_RBR",
  67 };
  68 #define mmr_name(off) mmr_names[(off) / 4]
  69
  70 static unsigned
  71 bfin_uart_io_write_buffer (struct hw *me, const void *source,
  72                            int space, address_word addr, unsigned nr_bytes)
  73 {
  74   struct bfin_uart *uart = hw_data (me);
  75   bu32 mmr_off;
  76   bu32 value;
  77   bu16 *valuep;
  78
  79   /* Invalid access mode is higher priority than missing register.  */
  80   if (!dv_bfin_mmr_require_16 (me, addr, nr_bytes, true))
  81     return 0;
  82
  83   value = dv_load_2 (source);
  84   mmr_off = addr - uart->base;
  85   valuep = (void *)((unsigned long)uart + mmr_base() + mmr_off);
  86
  87   HW_TRACE_WRITE ();
  88
  89   /* XXX: All MMRs are "8bit" ... what happens to high 8bits ?  */
  90
  91   switch (mmr_off)
  92     {
  93     case mmr_offset(thr):
  94       uart->thr = bfin_uart_write_byte (me, value, uart->mcr);
  95       if (uart->ier & ETBEI)
  96         hw_port_event (me, DV_PORT_TX, 1);
  97       break;
  98     case mmr_offset(ier_set):
  99       uart->ier |= value;
 100       break;
 101     case mmr_offset(ier_clear):
 102       dv_w1c_2 (&uart->ier, value, -1);
 103       break;
 104     case mmr_offset(lsr):
 105       dv_w1c_2 (valuep, value, TFI | BI | FE | PE | OE);
 106       break;
 107     case mmr_offset(rbr):
 108       /* XXX: Writes are ignored ?  */
 109       break;
 110     case mmr_offset(msr):
 111       dv_w1c_2 (valuep, value, SCTS);
 112       break;
 113     case mmr_offset(dll):
 114     case mmr_offset(dlh):
 115     case mmr_offset(gctl):
 116     case mmr_offset(lcr):
 117     case mmr_offset(mcr):
 118     case mmr_offset(scr):
 119       *valuep = value;
 120       break;
 121     default:
 122       dv_bfin_mmr_invalid (me, addr, nr_bytes, true);
 123       return 0;
 124     }
 125
 126   return nr_bytes;
 127 }
 128
 129 static unsigned
 130 bfin_uart_io_read_buffer (struct hw *me, void *dest,
 131                           int space, address_word addr, unsigned nr_bytes)
 132 {
 133   struct bfin_uart *uart = hw_data (me);
 134   bu32 mmr_off;
 135   bu16 *valuep;
 136
 137   /* Invalid access mode is higher priority than missing register.  */
 138   if (!dv_bfin_mmr_require_16 (me, addr, nr_bytes, false))
 139     return 0;
 140
 141   mmr_off = addr - uart->base;
 142   valuep = (void *)((unsigned long)uart + mmr_base() + mmr_off);
 143
 144   HW_TRACE_READ ();
 145
 146   switch (mmr_off)
 147     {
 148     case mmr_offset(rbr):
 149       uart->rbr = bfin_uart_get_next_byte (me, uart->rbr, uart->mcr, NULL);
 150       dv_store_2 (dest, uart->rbr);
 151       break;
 152     case mmr_offset(ier_set):
 153     case mmr_offset(ier_clear):
 154       dv_store_2 (dest, uart->ier);
 155       bfin_uart_reschedule (me);
 156       break;
 157     case mmr_offset(lsr):
 158       uart->lsr &= ~(DR | THRE | TEMT);
 159       uart->lsr |= bfin_uart_get_status (me);
 160     case mmr_offset(thr):
 161     case mmr_offset(msr):
 162     case mmr_offset(dll):
 163     case mmr_offset(dlh):
 164     case mmr_offset(gctl):
 165     case mmr_offset(lcr):
 166     case mmr_offset(mcr):
 167     case mmr_offset(scr):
 168       dv_store_2 (dest, *valuep);
 169       break;
 170     default:
 171       dv_bfin_mmr_invalid (me, addr, nr_bytes, false);
 172       return 0;
 173     }
 174
 175   return nr_bytes;
 176 }
 177
 178 static unsigned
 179 bfin_uart_dma_read_buffer (struct hw *me, void *dest, int space,
 180                            unsigned_word addr, unsigned nr_bytes)
 181 {
 182   HW_TRACE_DMA_READ ();
 183   return bfin_uart_read_buffer (me, dest, nr_bytes);
 184 }
 185
 186 static unsigned
 187 bfin_uart_dma_write_buffer (struct hw *me, const void *source,
 188                             int space, unsigned_word addr,
 189                             unsigned nr_bytes,
 190                             int violate_read_only_section)
 191 {
 192   struct bfin_uart *uart = hw_data (me);
 193   unsigned ret;
 194
 195   HW_TRACE_DMA_WRITE ();
 196
 197   ret = bfin_uart_write_buffer (me, source, nr_bytes);
 198
 199   if (ret == nr_bytes && (uart->ier & ETBEI))
 200     hw_port_event (me, DV_PORT_TX, 1);
 201
 202   return ret;
 203 }
 204
 205 static const struct hw_port_descriptor bfin_uart_ports[] =
 206 {
 207   { "tx",   DV_PORT_TX,   0, output_port, },
 208   { "rx",   DV_PORT_RX,   0, output_port, },
 209   { "stat", DV_PORT_STAT, 0, output_port, },
 210   { NULL, 0, 0, 0, },
 211 };
 212
 213 static void
 214 attach_bfin_uart_regs (struct hw *me, struct bfin_uart *uart)
 215 {
 216   address_word attach_address;
 217   int attach_space;
 218   unsigned attach_size;
 219   reg_property_spec reg;
 220
 221   if (hw_find_property (me, "reg") == NULL)
 222     hw_abort (me, "Missing \"reg\" property");
 223
 224   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
 225     hw_abort (me, "\"reg\" property must contain three addr/size entries");
 226
 227   hw_unit_address_to_attach_address (hw_parent (me),
 228                                      &reg.address,
 229                                      &attach_space, &attach_address, me);
 230   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
 231
 232   if (attach_size != BFIN_MMR_UART2_SIZE)
 233     hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_UART2_SIZE);
 234
 235   hw_attach_address (hw_parent (me),
 236                      0, attach_space, attach_address, attach_size, me);
 237
 238   uart->base = attach_address;
 239 }
 240
 241 static void
 242 bfin_uart_finish (struct hw *me)
 243 {
 244   struct bfin_uart *uart;
 245
 246   uart = HW_ZALLOC (me, struct bfin_uart);
 247
 248   set_hw_data (me, uart);
 249   set_hw_io_read_buffer (me, bfin_uart_io_read_buffer);
 250   set_hw_io_write_buffer (me, bfin_uart_io_write_buffer);
 251   set_hw_dma_read_buffer (me, bfin_uart_dma_read_buffer);
 252   set_hw_dma_write_buffer (me, bfin_uart_dma_write_buffer);
 253   set_hw_ports (me, bfin_uart_ports);
 254
 255   attach_bfin_uart_regs (me, uart);
 256
 257   /* Initialize the UART.  */
 258   uart->dll = 0x0001;
 259   uart->lsr = 0x0060;
 260 }
 261
 262 const struct hw_descriptor dv_bfin_uart2_descriptor[] =
 263 {
 264   {"bfin_uart2", bfin_uart_finish,},
 265   {NULL, NULL},
 266 };