1/* Copyright (c) 2013-2017 Jeffrey Pfau
 2 *
 3 * This Source Code Form is subject to the terms of the Mozilla Public
 4 * License, v. 2.0. If a copy of the MPL was not distributed with this
 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 6#include <mgba/internal/ds/ipc.h>
 7
 8#include <mgba/internal/ds/ds.h>
 9#include <mgba/internal/ds/io.h>
10
11void DSIPCWriteSYNC(struct ARMCore* remoteCpu, uint16_t* remoteIo, int16_t value) {
12	remoteIo[DS_REG_IPCSYNC >> 1] &= 0xFFF0;
13	remoteIo[DS_REG_IPCSYNC >> 1] |= (value >> 8) & 0x0F;
14	if (value & 0x2000 && remoteIo[DS_REG_IPCSYNC >> 1] & 0x4000) {
15		mLOG(DS_IO, STUB, "Unimplemented IPC IRQ");
16		UNUSED(remoteCpu);
17	}
18}
19
20int16_t DSIPCWriteFIFOCNT(struct DSCommon* dscore, int16_t value) {
21	value &= 0xC40C;
22	int16_t oldValue = dscore->memory.io[DS_REG_IPCFIFOCNT >> 1] & 0x4303;
23	int16_t newValue = value | oldValue;
24	// TODO: Does Enable set enabled on both ends?
25	if (DSIPCFIFOCNTIsError(value)) {
26		newValue = DSIPCFIFOCNTClearError(newValue);
27	}
28	if (DSIPCFIFOCNTIsSendClear(newValue)) {
29		CircleBufferClear(&dscore->ipc->fifo);
30		dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTFillRecvEmpty(dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1]);
31		newValue = DSIPCFIFOCNTFillSendEmpty(newValue);
32		newValue = DSIPCFIFOCNTClearSendClear(newValue);
33	}
34	return newValue;
35}
36
37void DSIPCWriteFIFO(struct DSCommon* dscore, int32_t value) {
38	if (!DSIPCFIFOCNTIsEnable(dscore->memory.io[DS_REG_IPCFIFOCNT >> 1])) {
39		return;
40	}
41	CircleBufferWrite32(&dscore->ipc->fifo, value);
42	size_t fullness = CircleBufferSize(&dscore->ipc->fifo);
43	if (fullness == 4) {
44		dscore->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTClearSendEmpty(dscore->memory.io[DS_REG_IPCFIFOCNT >> 1]);
45		dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTClearRecvEmpty(dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1]);
46		if (DSIPCFIFOCNTIsRecvIRQ(dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1])) {
47			// TODO: Adaptive time slicing?
48			DSRaiseIRQ(dscore->ipc->cpu, dscore->ipc->memory.io, DS_IRQ_IPC_NOT_EMPTY);
49		}
50	} else if (fullness == 64) {
51		dscore->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTFillSendFull(dscore->memory.io[DS_REG_IPCFIFOCNT >> 1]);
52		dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTFillRecvFull(dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1]);
53	}
54}
55
56int32_t DSIPCReadFIFO(struct DSCommon* dscore) {
57	if (!DSIPCFIFOCNTIsEnable(dscore->memory.io[DS_REG_IPCFIFOCNT >> 1])) {
58		return 0;
59	}
60	int32_t value = ((int32_t*) dscore->ipc->memory.io)[DS_REG_IPCFIFOSEND_LO >> 2]; // TODO: actual last value
61	CircleBufferRead32(&dscore->fifo, &value);
62	size_t fullness = CircleBufferSize(&dscore->fifo);
63	dscore->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTClearRecvFull(dscore->memory.io[DS_REG_IPCFIFOCNT >> 1]);
64	dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTClearSendFull(dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1]);
65	if (fullness == 0) {
66		dscore->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTFillRecvEmpty(dscore->memory.io[DS_REG_IPCFIFOCNT >> 1]);
67		dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1] = DSIPCFIFOCNTFillSendEmpty(dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1]);
68		if (DSIPCFIFOCNTIsSendIRQ(dscore->ipc->memory.io[DS_REG_IPCFIFOCNT >> 1])) {
69			// TODO: Adaptive time slicing?
70			DSRaiseIRQ(dscore->ipc->cpu, dscore->ipc->memory.io, DS_IRQ_IPC_NOT_EMPTY);
71		}
72	}
73	return value;
74}