xref: /netbsd-src/external/gpl3/gdb/dist/sim/bfin/dv-bfin_gpio.c (revision 1f4e7eb9e5e045e008f1894823a8e4e6c9f46890)
1 /* Blackfin General Purpose Ports (GPIO) model
2 
3    Copyright (C) 2010-2024 Free Software Foundation, Inc.
4    Contributed by Analog Devices, Inc.
5 
6    This file is part of simulators.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20 
21 /* This must come before any other includes.  */
22 #include "defs.h"
23 
24 #include "sim-main.h"
25 #include "devices.h"
26 #include "dv-bfin_gpio.h"
27 
28 struct bfin_gpio
29 {
30   bu32 base;
31 
32   bu16 int_state;
33 
34   /* Order after here is important -- matches hardware MMR layout.  */
35   bu16 BFIN_MMR_16(data);
36   bu16 BFIN_MMR_16(clear);
37   bu16 BFIN_MMR_16(set);
38   bu16 BFIN_MMR_16(toggle);
39   bu16 BFIN_MMR_16(maska);
40   bu16 BFIN_MMR_16(maska_clear);
41   bu16 BFIN_MMR_16(maska_set);
42   bu16 BFIN_MMR_16(maska_toggle);
43   bu16 BFIN_MMR_16(maskb);
44   bu16 BFIN_MMR_16(maskb_clear);
45   bu16 BFIN_MMR_16(maskb_set);
46   bu16 BFIN_MMR_16(maskb_toggle);
47   bu16 BFIN_MMR_16(dir);
48   bu16 BFIN_MMR_16(polar);
49   bu16 BFIN_MMR_16(edge);
50   bu16 BFIN_MMR_16(both);
51   bu16 BFIN_MMR_16(inen);
52 };
53 #define mmr_base()      offsetof(struct bfin_gpio, data)
54 #define mmr_offset(mmr) (offsetof(struct bfin_gpio, mmr) - mmr_base())
55 
56 static const char * const mmr_names[] =
57 {
58   "PORTIO", "PORTIO_CLEAR", "PORTIO_SET", "PORTIO_TOGGLE", "PORTIO_MASKA",
59   "PORTIO_MASKA_CLEAR", "PORTIO_MASKA_SET", "PORTIO_MASKA_TOGGLE",
60   "PORTIO_MASKB", "PORTIO_MASKB_CLEAR", "PORTIO_MASKB_SET",
61   "PORTIO_MASKB_TOGGLE", "PORTIO_DIR", "PORTIO_POLAR", "PORTIO_EDGE",
62   "PORTIO_BOTH", "PORTIO_INEN",
63 };
64 #define mmr_name(off) mmr_names[(off) / 4]
65 
66 static void
67 bfin_gpio_forward_int (struct hw *me, struct bfin_gpio *port, bu32 mask,
68 		       int dst_port)
69 {
70   HW_TRACE ((me, "resending levels on port %c", 'a' + dst_port));
71   hw_port_event (me, dst_port, !!(port->int_state & mask));
72 }
73 static void
74 bfin_gpio_forward_ints (struct hw *me, struct bfin_gpio *port)
75 {
76   bfin_gpio_forward_int (me, port, port->maska, 0);
77   bfin_gpio_forward_int (me, port, port->maskb, 1);
78 }
79 
80 static void
81 bfin_gpio_forward_ouput (struct hw *me, struct bfin_gpio *port, bu32 odata)
82 {
83   int pin, value, ovalue, bit;
84 
85   for (pin = 0; pin < 16; ++pin)
86     {
87       bit = 1 << pin;
88 
89       /* Make sure this is an output pin.  */
90       if (!(port->dir & bit))
91 	continue;
92 
93       /* Only signal port if the pin changes value.  */
94       value = !!(port->data & bit);
95       ovalue = !!(odata & bit);
96       if (value == ovalue)
97 	continue;
98 
99       HW_TRACE ((me, "outputting gpio %i changed to %i", pin, value));
100       hw_port_event (me, pin, value);
101     }
102 }
103 
104 static unsigned
105 bfin_gpio_io_write_buffer (struct hw *me, const void *source, int space,
106 			   address_word addr, unsigned nr_bytes)
107 {
108   struct bfin_gpio *port = hw_data (me);
109   bu32 mmr_off;
110   bu16 value;
111   bu16 *valuep;
112   bu32 data = port->data;
113 
114   /* Invalid access mode is higher priority than missing register.  */
115   if (!dv_bfin_mmr_require_16 (me, addr, nr_bytes, true))
116     return 0;
117 
118   value = dv_load_2 (source);
119   mmr_off = addr - port->base;
120   valuep = (void *)((uintptr_t)port + mmr_base() + mmr_off);
121 
122   HW_TRACE_WRITE ();
123 
124   switch (mmr_off)
125     {
126     case mmr_offset(data):
127     case mmr_offset(maska):
128     case mmr_offset(maskb):
129     case mmr_offset(dir):
130     case mmr_offset(polar):
131     case mmr_offset(edge):
132     case mmr_offset(both):
133     case mmr_offset(inen):
134       *valuep = value;
135       break;
136     case mmr_offset(clear):
137     case mmr_offset(maska_clear):
138     case mmr_offset(maskb_clear):
139       /* We want to clear the related data MMR.  */
140       valuep -= 2;
141       dv_w1c_2 (valuep, value, -1);
142       break;
143     case mmr_offset(set):
144     case mmr_offset(maska_set):
145     case mmr_offset(maskb_set):
146       /* We want to set the related data MMR.  */
147       valuep -= 4;
148       *valuep |= value;
149       break;
150     case mmr_offset(toggle):
151     case mmr_offset(maska_toggle):
152     case mmr_offset(maskb_toggle):
153       /* We want to toggle the related data MMR.  */
154       valuep -= 6;
155       *valuep ^= value;
156       break;
157     default:
158       dv_bfin_mmr_invalid (me, addr, nr_bytes, true);
159       return 0;
160     }
161 
162   /* If updating masks, make sure we send updated port info.  */
163   switch (mmr_off)
164     {
165     case mmr_offset(dir):
166     case mmr_offset(data) ... mmr_offset(toggle):
167       bfin_gpio_forward_ouput (me, port, data);
168       break;
169     case mmr_offset(maska) ... mmr_offset(maska_toggle):
170       bfin_gpio_forward_int (me, port, port->maska, 0);
171       break;
172     case mmr_offset(maskb) ... mmr_offset(maskb_toggle):
173       bfin_gpio_forward_int (me, port, port->maskb, 1);
174       break;
175     }
176 
177   return nr_bytes;
178 }
179 
180 static unsigned
181 bfin_gpio_io_read_buffer (struct hw *me, void *dest, int space,
182 			  address_word addr, unsigned nr_bytes)
183 {
184   struct bfin_gpio *port = hw_data (me);
185   bu32 mmr_off;
186   bu16 *valuep;
187 
188   /* Invalid access mode is higher priority than missing register.  */
189   if (!dv_bfin_mmr_require_16 (me, addr, nr_bytes, false))
190     return 0;
191 
192   mmr_off = addr - port->base;
193   valuep = (void *)((uintptr_t)port + mmr_base() + mmr_off);
194 
195   HW_TRACE_READ ();
196 
197   switch (mmr_off)
198     {
199     case mmr_offset(data):
200     case mmr_offset(clear):
201     case mmr_offset(set):
202     case mmr_offset(toggle):
203       dv_store_2 (dest, port->data);
204       break;
205     case mmr_offset(maska):
206     case mmr_offset(maska_clear):
207     case mmr_offset(maska_set):
208     case mmr_offset(maska_toggle):
209       dv_store_2 (dest, port->maska);
210       break;
211     case mmr_offset(maskb):
212     case mmr_offset(maskb_clear):
213     case mmr_offset(maskb_set):
214     case mmr_offset(maskb_toggle):
215       dv_store_2 (dest, port->maskb);
216       break;
217     case mmr_offset(dir):
218     case mmr_offset(polar):
219     case mmr_offset(edge):
220     case mmr_offset(both):
221     case mmr_offset(inen):
222       dv_store_2 (dest, *valuep);
223       break;
224     default:
225       dv_bfin_mmr_invalid (me, addr, nr_bytes, false);
226       return 0;
227     }
228 
229   return nr_bytes;
230 }
231 
232 static const struct hw_port_descriptor bfin_gpio_ports[] =
233 {
234   { "mask_a", 0, 0, output_port, },
235   { "mask_b", 1, 0, output_port, },
236   { "p0",     0, 0, bidirect_port, },
237   { "p1",     1, 0, bidirect_port, },
238   { "p2",     2, 0, bidirect_port, },
239   { "p3",     3, 0, bidirect_port, },
240   { "p4",     4, 0, bidirect_port, },
241   { "p5",     5, 0, bidirect_port, },
242   { "p6",     6, 0, bidirect_port, },
243   { "p7",     7, 0, bidirect_port, },
244   { "p8",     8, 0, bidirect_port, },
245   { "p9",     9, 0, bidirect_port, },
246   { "p10",   10, 0, bidirect_port, },
247   { "p11",   11, 0, bidirect_port, },
248   { "p12",   12, 0, bidirect_port, },
249   { "p13",   13, 0, bidirect_port, },
250   { "p14",   14, 0, bidirect_port, },
251   { "p15",   15, 0, bidirect_port, },
252   { NULL, 0, 0, 0, },
253 };
254 
255 static void
256 bfin_gpio_port_event (struct hw *me, int my_port, struct hw *source,
257 		      int source_port, int level)
258 {
259   struct bfin_gpio *port = hw_data (me);
260   bool olvl, nlvl;
261   bu32 bit = (1 << my_port);
262 
263   /* Normalize the level value.  A simulated device can send any value
264      it likes to us, but in reality we only care about 0 and 1.  This
265      lets us assume only those two values below.  */
266   level = !!level;
267 
268   HW_TRACE ((me, "pin %i set to %i", my_port, level));
269 
270   /* Only screw with state if this pin is set as an input, and the
271      input is actually enabled.  */
272   if ((port->dir & bit) || !(port->inen & bit))
273     {
274       HW_TRACE ((me, "ignoring level/int due to DIR=%i INEN=%i",
275 		 !!(port->dir & bit), !!(port->inen & bit)));
276       return;
277     }
278 
279   /* Get the old pin state for calculating an interrupt.  */
280   olvl = !!(port->data & bit);
281 
282   /* Update the new pin state.  */
283   port->data = (port->data & ~bit) | (level << my_port);
284 
285   /* See if this state transition will generate an interrupt.  */
286   nlvl = !!(port->data & bit);
287 
288   if (port->edge & bit)
289     {
290       /* Pin is edge triggered.  */
291       if (port->both & bit)
292 	{
293 	  /* Both edges.  */
294 	  if (olvl == nlvl)
295 	    {
296 	      HW_TRACE ((me, "ignoring int due to EDGE=%i BOTH=%i lvl=%i->%i",
297 			 !!(port->edge & bit), !!(port->both & bit),
298 			 olvl, nlvl));
299 	      return;
300 	    }
301 	}
302       else
303 	{
304 	  /* Just one edge.  */
305 	  if (!(((port->polar & bit) && olvl > nlvl)
306 		|| (!(port->polar & bit) && olvl < nlvl)))
307 	    {
308 	      HW_TRACE ((me, "ignoring int due to EDGE=%i POLAR=%i lvl=%i->%i",
309 			 !!(port->edge & bit), !!(port->polar & bit),
310 			 olvl, nlvl));
311 	      return;
312 	    }
313 	}
314 
315       /* Send the signal up, and then fall through to clear it.  */
316       port->int_state |= bit;
317       bfin_gpio_forward_ints (me, port);
318       port->int_state &= ~bit;
319     }
320   else
321     {
322       /* Pin is level triggered.  */
323       if (nlvl == !!(port->polar & bit))
324 	{
325 	  HW_TRACE ((me, "ignoring int due to EDGE=%i POLAR=%i lvl=%i",
326 		     !!(port->edge & bit), !!(port->polar & bit), nlvl));
327 	  /* We still need to signal SIC to clear the int, so don't return.  */
328 	  port->int_state &= ~bit;
329 	}
330       else
331 	port->int_state |= bit;
332     }
333 
334   bfin_gpio_forward_ints (me, port);
335 }
336 
337 static void
338 attach_bfin_gpio_regs (struct hw *me, struct bfin_gpio *port)
339 {
340   address_word attach_address;
341   int attach_space;
342   unsigned attach_size;
343   reg_property_spec reg;
344 
345   if (hw_find_property (me, "reg") == NULL)
346     hw_abort (me, "Missing \"reg\" property");
347 
348   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
349     hw_abort (me, "\"reg\" property must contain three addr/size entries");
350 
351   hw_unit_address_to_attach_address (hw_parent (me),
352 				     &reg.address,
353 				     &attach_space, &attach_address, me);
354   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
355 
356   if (attach_size != BFIN_MMR_GPIO_SIZE)
357     hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_GPIO_SIZE);
358 
359   hw_attach_address (hw_parent (me),
360 		     0, attach_space, attach_address, attach_size, me);
361 
362   port->base = attach_address;
363 }
364 
365 static void
366 bfin_gpio_finish (struct hw *me)
367 {
368   struct bfin_gpio *port;
369 
370   port = HW_ZALLOC (me, struct bfin_gpio);
371 
372   set_hw_data (me, port);
373   set_hw_io_read_buffer (me, bfin_gpio_io_read_buffer);
374   set_hw_io_write_buffer (me, bfin_gpio_io_write_buffer);
375   set_hw_ports (me, bfin_gpio_ports);
376   set_hw_port_event (me, bfin_gpio_port_event);
377 
378   attach_bfin_gpio_regs (me, port);
379 }
380 
381 const struct hw_descriptor dv_bfin_gpio_descriptor[] =
382 {
383   {"bfin_gpio", bfin_gpio_finish,},
384   {NULL, NULL},
385 };
386