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-rw-r--r--hw/dma.c395
1 files changed, 395 insertions, 0 deletions
diff --git a/hw/dma.c b/hw/dma.c
new file mode 100644
index 0000000000..ac85efba15
--- /dev/null
+++ b/hw/dma.c
@@ -0,0 +1,395 @@
+/*
+ * QEMU DMA emulation
+ *
+ * Copyright (c) 2003 Vassili Karpov (malc)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <inttypes.h>
+
+#include "vl.h"
+#include "cpu.h"
+
+#define log(...) fprintf (stderr, "dma: " __VA_ARGS__)
+#ifdef DEBUG_DMA
+#define lwarn(...) fprintf (stderr, "dma: " __VA_ARGS__)
+#define linfo(...) fprintf (stderr, "dma: " __VA_ARGS__)
+#define ldebug(...) fprintf (stderr, "dma: " __VA_ARGS__)
+#else
+#define lwarn(...)
+#define linfo(...)
+#define ldebug(...)
+#endif
+
+#define MEM_REAL(addr) ((addr)+(uint32_t)(phys_ram_base))
+#define LENOFA(a) ((int) (sizeof(a)/sizeof(a[0])))
+
+struct dma_regs {
+ int now[2];
+ uint16_t base[2];
+ uint8_t mode;
+ uint8_t page;
+ uint8_t dack;
+ uint8_t eop;
+ DMA_read_handler read_handler;
+ DMA_misc_handler misc_handler;
+};
+
+#define ADDR 0
+#define COUNT 1
+
+static struct dma_cont {
+ uint8_t status;
+ uint8_t command;
+ uint8_t mask;
+ uint8_t flip_flop;
+ struct dma_regs regs[4];
+} dma_controllers[2];
+
+enum {
+ CMD_MEMORY_TO_MEMORY = 0x01,
+ CMD_FIXED_ADDRESS = 0x02,
+ CMD_BLOCK_CONTROLLER = 0x04,
+ CMD_COMPRESSED_TIME = 0x08,
+ CMD_CYCLIC_PRIORITY = 0x10,
+ CMD_EXTENDED_WRITE = 0x20,
+ CMD_LOW_DREQ = 0x40,
+ CMD_LOW_DACK = 0x80,
+ CMD_NOT_SUPPORTED = CMD_MEMORY_TO_MEMORY | CMD_FIXED_ADDRESS
+ | CMD_COMPRESSED_TIME | CMD_CYCLIC_PRIORITY | CMD_EXTENDED_WRITE
+ | CMD_LOW_DREQ | CMD_LOW_DACK
+
+};
+
+static void write_page (struct CPUX86State *env, uint32_t nport, uint32_t data)
+{
+ int ichan;
+ int ncont;
+ static int channels[8] = {-1, 2, 3, 1, -1, -1, -1, 0};
+
+ ncont = nport > 0x87;
+ ichan = channels[nport - 0x80 - (ncont << 3)];
+
+ if (-1 == ichan) {
+ log ("invalid channel %#x %#x\n", nport, data);
+ return;
+ }
+
+ dma_controllers[ncont].regs[ichan].page = data;
+}
+
+static void init_chan (int ncont, int ichan)
+{
+ struct dma_regs *r;
+
+ r = dma_controllers[ncont].regs + ichan;
+ r->now[ADDR] = r->base[0] << ncont;
+ r->now[COUNT] = 0;
+}
+
+static inline int getff (int ncont)
+{
+ int ff;
+
+ ff = dma_controllers[ncont].flip_flop;
+ dma_controllers[ncont].flip_flop = !ff;
+ return ff;
+}
+
+static uint32_t read_chan (struct CPUX86State *env, uint32_t nport)
+{
+ int ff;
+ int ncont, ichan, nreg;
+ struct dma_regs *r;
+ int val;
+
+ ncont = nport > 7;
+ ichan = (nport >> (1 + ncont)) & 3;
+ nreg = (nport >> ncont) & 1;
+ r = dma_controllers[ncont].regs + ichan;
+
+ ff = getff (ncont);
+
+ if (nreg)
+ val = (r->base[COUNT] << ncont) - r->now[COUNT];
+ else
+ val = r->now[ADDR] + r->now[COUNT];
+
+ return (val >> (ncont + (ff << 3))) & 0xff;
+}
+
+static void write_chan (uint32_t nport, int size, uint32_t data)
+{
+ int ncont, ichan, nreg;
+ struct dma_regs *r;
+
+ ncont = nport > 7;
+ ichan = (nport >> (1 + ncont)) & 3;
+ nreg = (nport >> ncont) & 1;
+ r = dma_controllers[ncont].regs + ichan;
+
+ if (2 == size) {
+ r->base[nreg] = data;
+ init_chan (ncont, ichan);
+ }
+ else {
+ if (getff (ncont)) {
+ r->base[nreg] = (r->base[nreg] & 0xff) | ((data << 8) & 0xff00);
+ init_chan (ncont, ichan);
+ }
+ else {
+ r->base[nreg] = (r->base[nreg] & 0xff00) | (data & 0xff);
+ }
+ }
+}
+static void write_chanb (struct CPUX86State *env, uint32_t nport, uint32_t data)
+{
+ write_chan (nport, 1, data);
+}
+
+static void write_chanw (struct CPUX86State *env, uint32_t nport, uint32_t data)
+{
+ write_chan (nport, 2, data);
+}
+
+static void write_cont (struct CPUX86State *env, uint32_t nport, uint32_t data)
+{
+ int iport, ichan, ncont;
+ struct dma_cont *d;
+
+ ncont = nport > 0xf;
+ ichan = -1;
+
+ d = dma_controllers + ncont;
+ if (ncont) {
+ iport = ((nport - 0xd0) >> 1) + 8;
+ }
+ else {
+ iport = nport;
+ }
+
+ switch (iport) {
+ case 8: /* command */
+ if (data && (data | CMD_NOT_SUPPORTED)) {
+ log ("command %#x not supported\n", data);
+ goto error;
+ }
+ d->command = data;
+ break;
+
+ case 9:
+ ichan = data & 3;
+ if (data & 4) {
+ d->status |= 1 << (ichan + 4);
+ }
+ else {
+ d->status &= ~(1 << (ichan + 4));
+ }
+ d->status &= ~(1 << ichan);
+ break;
+
+ case 0xa: /* single mask */
+ if (data & 4)
+ d->mask |= 1 << (data & 3);
+ else
+ d->mask &= ~(1 << (data & 3));
+ break;
+
+ case 0xb: /* mode */
+ {
+#ifdef DMA_DEBUG
+ int op;
+ int ai;
+ int dir;
+ int opmode;
+
+ ichan = val & 3;
+ op = (val >> 2) & 3;
+ ai = (val >> 4) & 1;
+ dir = (val >> 5) & 1;
+ opmode = (val >> 6) & 3;
+
+ linfo ("ichan %d, op %d, ai %d, dir %d, opmode %d\n",
+ ichan, op, ai, dir, opmode);
+#endif
+
+ d->regs[ichan].mode = data;
+ break;
+ }
+
+ case 0xc: /* clear flip flop */
+ d->flip_flop = 0;
+ break;
+
+ case 0xd: /* reset */
+ d->flip_flop = 0;
+ d->mask = ~0;
+ d->status = 0;
+ d->command = 0;
+ break;
+
+ case 0xe: /* clear mask for all channels */
+ d->mask = 0;
+ break;
+
+ case 0xf: /* write mask for all channels */
+ d->mask = data;
+ break;
+
+ default:
+ log ("dma: unknown iport %#x\n", iport);
+ goto error;
+ }
+
+#ifdef DMA_DEBUG
+ if (0xc != iport) {
+ linfo ("nport %#06x, ncont %d, ichan % 2d, val %#06x\n",
+ nport, d != dma_controllers, ichan, data);
+ }
+#endif
+ return;
+
+ error:
+ abort ();
+}
+
+int DMA_get_channel_mode (int nchan)
+{
+ return dma_controllers[nchan > 3].regs[nchan & 3].mode;
+}
+
+void DMA_hold_DREQ (int nchan)
+{
+ int ncont, ichan;
+
+ ncont = nchan > 3;
+ ichan = nchan & 3;
+ linfo ("held cont=%d chan=%d\n", ncont, ichan);
+ dma_controllers[ncont].status |= 1 << (ichan + 4);
+}
+
+void DMA_release_DREQ (int nchan)
+{
+ int ncont, ichan;
+
+ ncont = nchan > 3;
+ ichan = nchan & 3;
+ linfo ("released cont=%d chan=%d\n", ncont, ichan);
+ dma_controllers[ncont].status &= ~(1 << (ichan + 4));
+}
+
+static void channel_run (int ncont, int ichan)
+{
+ struct dma_regs *r;
+ int n;
+ int irq;
+ uint32_t addr;
+/* int ai, dir; */
+
+ r = dma_controllers[ncont].regs + ichan;
+/* ai = r->mode & 16; */
+/* dir = r->mode & 32 ? -1 : 1; */
+
+ addr = MEM_REAL ((r->page << 16) | r->now[ADDR]);
+
+ irq = -1;
+ n = r->read_handler (addr, (r->base[COUNT] << ncont) + (1 << ncont), &irq);
+ r->now[COUNT] = n;
+
+ ldebug ("dma_pos %d irq %d size %d\n",
+ n, irq, (r->base[1] << ncont) + (1 << ncont));
+
+ if (-1 != irq) {
+ pic_set_irq (irq, 1);
+ }
+}
+
+void DMA_run (void)
+{
+ static int in_dma;
+ struct dma_cont *d;
+ int icont, ichan;
+
+ if (in_dma) {
+ log ("attempt to re-enter dma\n");
+ return;
+ }
+
+ in_dma = 1;
+ d = dma_controllers;
+
+ for (icont = 0; icont < 2; icont++, d++) {
+ for (ichan = 0; ichan < 4; ichan++) {
+ int mask;
+
+ mask = 1 << ichan;
+
+ if ((0 == (d->mask & mask)) && (0 != (d->status & (mask << 4))))
+ channel_run (icont, ichan);
+ }
+ }
+ in_dma = 0;
+}
+
+void DMA_register_channel (int nchan,
+ DMA_read_handler read_handler,
+ DMA_misc_handler misc_handler)
+{
+ struct dma_regs *r;
+ int ichan, ncont;
+
+ ncont = nchan > 3;
+ ichan = nchan & 3;
+
+ r = dma_controllers[ncont].regs + ichan;
+ r->read_handler = read_handler;
+ r->misc_handler = misc_handler;
+}
+
+void DMA_init (void)
+{
+ int i;
+ int page_port_list[] = { 0x1, 0x2, 0x3, 0x7 };
+
+ for (i = 0; i < 8; i++) {
+ register_ioport_write (i, 1, write_chanb, 1);
+ register_ioport_write (i, 1, write_chanw, 2);
+
+ register_ioport_write (0xc0 + (i << 1), 1, write_chanb, 1);
+ register_ioport_write (0xc0 + (i << 1), 1, write_chanw, 2);
+
+ register_ioport_read (i, 1, read_chan, 1);
+ register_ioport_read (0xc0 + (i << 1), 1, read_chan, 2);
+ }
+
+ for (i = 0; i < LENOFA (page_port_list); i++) {
+ register_ioport_write (page_port_list[i] + 0x80, 1, write_page, 1);
+ register_ioport_write (page_port_list[i] + 0x88, 1, write_page, 1);
+ }
+
+ for (i = 0; i < 8; i++) {
+ register_ioport_write (i + 8, 1, write_cont, 1);
+ register_ioport_write (0xd0 + (i << 1), 1, write_cont, 1);
+ }
+
+ write_cont (NULL, 0xd, 0);
+ write_cont (NULL, 0xdd, 0);
+}
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