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-rw-r--r--hw/dma/i8257.c600
1 files changed, 600 insertions, 0 deletions
diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c
new file mode 100644
index 0000000000..eb60d45178
--- /dev/null
+++ b/hw/dma/i8257.c
@@ -0,0 +1,600 @@
+/*
+ * QEMU DMA emulation
+ *
+ * Copyright (c) 2003-2004 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 "hw/hw.h"
+#include "hw/isa/isa.h"
+#include "qemu/main-loop.h"
+
+/* #define DEBUG_DMA */
+
+#define dolog(...) fprintf (stderr, "dma: " __VA_ARGS__)
+#ifdef DEBUG_DMA
+#define linfo(...) fprintf (stderr, "dma: " __VA_ARGS__)
+#define ldebug(...) fprintf (stderr, "dma: " __VA_ARGS__)
+#else
+#define linfo(...)
+#define ldebug(...)
+#endif
+
+struct dma_regs {
+ int now[2];
+ uint16_t base[2];
+ uint8_t mode;
+ uint8_t page;
+ uint8_t pageh;
+ uint8_t dack;
+ uint8_t eop;
+ DMA_transfer_handler transfer_handler;
+ void *opaque;
+};
+
+#define ADDR 0
+#define COUNT 1
+
+static struct dma_cont {
+ uint8_t status;
+ uint8_t command;
+ uint8_t mask;
+ uint8_t flip_flop;
+ int dshift;
+ struct dma_regs regs[4];
+ qemu_irq *cpu_request_exit;
+ MemoryRegion channel_io;
+ MemoryRegion cont_io;
+} 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 DMA_run (void);
+
+static int channels[8] = {-1, 2, 3, 1, -1, -1, -1, 0};
+
+static void write_page (void *opaque, uint32_t nport, uint32_t data)
+{
+ struct dma_cont *d = opaque;
+ int ichan;
+
+ ichan = channels[nport & 7];
+ if (-1 == ichan) {
+ dolog ("invalid channel %#x %#x\n", nport, data);
+ return;
+ }
+ d->regs[ichan].page = data;
+}
+
+static void write_pageh (void *opaque, uint32_t nport, uint32_t data)
+{
+ struct dma_cont *d = opaque;
+ int ichan;
+
+ ichan = channels[nport & 7];
+ if (-1 == ichan) {
+ dolog ("invalid channel %#x %#x\n", nport, data);
+ return;
+ }
+ d->regs[ichan].pageh = data;
+}
+
+static uint32_t read_page (void *opaque, uint32_t nport)
+{
+ struct dma_cont *d = opaque;
+ int ichan;
+
+ ichan = channels[nport & 7];
+ if (-1 == ichan) {
+ dolog ("invalid channel read %#x\n", nport);
+ return 0;
+ }
+ return d->regs[ichan].page;
+}
+
+static uint32_t read_pageh (void *opaque, uint32_t nport)
+{
+ struct dma_cont *d = opaque;
+ int ichan;
+
+ ichan = channels[nport & 7];
+ if (-1 == ichan) {
+ dolog ("invalid channel read %#x\n", nport);
+ return 0;
+ }
+ return d->regs[ichan].pageh;
+}
+
+static inline void init_chan (struct dma_cont *d, int ichan)
+{
+ struct dma_regs *r;
+
+ r = d->regs + ichan;
+ r->now[ADDR] = r->base[ADDR] << d->dshift;
+ r->now[COUNT] = 0;
+}
+
+static inline int getff (struct dma_cont *d)
+{
+ int ff;
+
+ ff = d->flip_flop;
+ d->flip_flop = !ff;
+ return ff;
+}
+
+static uint64_t read_chan(void *opaque, hwaddr nport, unsigned size)
+{
+ struct dma_cont *d = opaque;
+ int ichan, nreg, iport, ff, val, dir;
+ struct dma_regs *r;
+
+ iport = (nport >> d->dshift) & 0x0f;
+ ichan = iport >> 1;
+ nreg = iport & 1;
+ r = d->regs + ichan;
+
+ dir = ((r->mode >> 5) & 1) ? -1 : 1;
+ ff = getff (d);
+ if (nreg)
+ val = (r->base[COUNT] << d->dshift) - r->now[COUNT];
+ else
+ val = r->now[ADDR] + r->now[COUNT] * dir;
+
+ ldebug ("read_chan %#x -> %d\n", iport, val);
+ return (val >> (d->dshift + (ff << 3))) & 0xff;
+}
+
+static void write_chan(void *opaque, hwaddr nport, uint64_t data,
+ unsigned size)
+{
+ struct dma_cont *d = opaque;
+ int iport, ichan, nreg;
+ struct dma_regs *r;
+
+ iport = (nport >> d->dshift) & 0x0f;
+ ichan = iport >> 1;
+ nreg = iport & 1;
+ r = d->regs + ichan;
+ if (getff (d)) {
+ r->base[nreg] = (r->base[nreg] & 0xff) | ((data << 8) & 0xff00);
+ init_chan (d, ichan);
+ } else {
+ r->base[nreg] = (r->base[nreg] & 0xff00) | (data & 0xff);
+ }
+}
+
+static void write_cont(void *opaque, hwaddr nport, uint64_t data,
+ unsigned size)
+{
+ struct dma_cont *d = opaque;
+ int iport, ichan = 0;
+
+ iport = (nport >> d->dshift) & 0x0f;
+ switch (iport) {
+ case 0x00: /* command */
+ if ((data != 0) && (data & CMD_NOT_SUPPORTED)) {
+ dolog("command %"PRIx64" not supported\n", data);
+ return;
+ }
+ d->command = data;
+ break;
+
+ case 0x01:
+ ichan = data & 3;
+ if (data & 4) {
+ d->status |= 1 << (ichan + 4);
+ }
+ else {
+ d->status &= ~(1 << (ichan + 4));
+ }
+ d->status &= ~(1 << ichan);
+ DMA_run();
+ break;
+
+ case 0x02: /* single mask */
+ if (data & 4)
+ d->mask |= 1 << (data & 3);
+ else
+ d->mask &= ~(1 << (data & 3));
+ DMA_run();
+ break;
+
+ case 0x03: /* mode */
+ {
+ ichan = data & 3;
+#ifdef DEBUG_DMA
+ {
+ int op, ai, dir, opmode;
+ op = (data >> 2) & 3;
+ ai = (data >> 4) & 1;
+ dir = (data >> 5) & 1;
+ opmode = (data >> 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 0x04: /* clear flip flop */
+ d->flip_flop = 0;
+ break;
+
+ case 0x05: /* reset */
+ d->flip_flop = 0;
+ d->mask = ~0;
+ d->status = 0;
+ d->command = 0;
+ break;
+
+ case 0x06: /* clear mask for all channels */
+ d->mask = 0;
+ DMA_run();
+ break;
+
+ case 0x07: /* write mask for all channels */
+ d->mask = data;
+ DMA_run();
+ break;
+
+ default:
+ dolog ("unknown iport %#x\n", iport);
+ break;
+ }
+
+#ifdef DEBUG_DMA
+ if (0xc != iport) {
+ linfo ("write_cont: nport %#06x, ichan % 2d, val %#06x\n",
+ nport, ichan, data);
+ }
+#endif
+}
+
+static uint64_t read_cont(void *opaque, hwaddr nport, unsigned size)
+{
+ struct dma_cont *d = opaque;
+ int iport, val;
+
+ iport = (nport >> d->dshift) & 0x0f;
+ switch (iport) {
+ case 0x00: /* status */
+ val = d->status;
+ d->status &= 0xf0;
+ break;
+ case 0x01: /* mask */
+ val = d->mask;
+ break;
+ default:
+ val = 0;
+ break;
+ }
+
+ ldebug ("read_cont: nport %#06x, iport %#04x val %#x\n", nport, iport, val);
+ return val;
+}
+
+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);
+ DMA_run();
+}
+
+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));
+ DMA_run();
+}
+
+static void channel_run (int ncont, int ichan)
+{
+ int n;
+ struct dma_regs *r = &dma_controllers[ncont].regs[ichan];
+#ifdef DEBUG_DMA
+ int dir, opmode;
+
+ dir = (r->mode >> 5) & 1;
+ opmode = (r->mode >> 6) & 3;
+
+ if (dir) {
+ dolog ("DMA in address decrement mode\n");
+ }
+ if (opmode != 1) {
+ dolog ("DMA not in single mode select %#x\n", opmode);
+ }
+#endif
+
+ n = r->transfer_handler (r->opaque, ichan + (ncont << 2),
+ r->now[COUNT], (r->base[COUNT] + 1) << ncont);
+ r->now[COUNT] = n;
+ ldebug ("dma_pos %d size %d\n", n, (r->base[COUNT] + 1) << ncont);
+}
+
+static QEMUBH *dma_bh;
+
+static void DMA_run (void)
+{
+ struct dma_cont *d;
+ int icont, ichan;
+ int rearm = 0;
+ static int running = 0;
+
+ if (running) {
+ rearm = 1;
+ goto out;
+ } else {
+ running = 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);
+ rearm = 1;
+ }
+ }
+ }
+
+ running = 0;
+out:
+ if (rearm)
+ qemu_bh_schedule_idle(dma_bh);
+}
+
+static void DMA_run_bh(void *unused)
+{
+ DMA_run();
+}
+
+void DMA_register_channel (int nchan,
+ DMA_transfer_handler transfer_handler,
+ void *opaque)
+{
+ struct dma_regs *r;
+ int ichan, ncont;
+
+ ncont = nchan > 3;
+ ichan = nchan & 3;
+
+ r = dma_controllers[ncont].regs + ichan;
+ r->transfer_handler = transfer_handler;
+ r->opaque = opaque;
+}
+
+int DMA_read_memory (int nchan, void *buf, int pos, int len)
+{
+ struct dma_regs *r = &dma_controllers[nchan > 3].regs[nchan & 3];
+ hwaddr addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR];
+
+ if (r->mode & 0x20) {
+ int i;
+ uint8_t *p = buf;
+
+ cpu_physical_memory_read (addr - pos - len, buf, len);
+ /* What about 16bit transfers? */
+ for (i = 0; i < len >> 1; i++) {
+ uint8_t b = p[len - i - 1];
+ p[i] = b;
+ }
+ }
+ else
+ cpu_physical_memory_read (addr + pos, buf, len);
+
+ return len;
+}
+
+int DMA_write_memory (int nchan, void *buf, int pos, int len)
+{
+ struct dma_regs *r = &dma_controllers[nchan > 3].regs[nchan & 3];
+ hwaddr addr = ((r->pageh & 0x7f) << 24) | (r->page << 16) | r->now[ADDR];
+
+ if (r->mode & 0x20) {
+ int i;
+ uint8_t *p = buf;
+
+ cpu_physical_memory_write (addr - pos - len, buf, len);
+ /* What about 16bit transfers? */
+ for (i = 0; i < len; i++) {
+ uint8_t b = p[len - i - 1];
+ p[i] = b;
+ }
+ }
+ else
+ cpu_physical_memory_write (addr + pos, buf, len);
+
+ return len;
+}
+
+/* request the emulator to transfer a new DMA memory block ASAP */
+void DMA_schedule(int nchan)
+{
+ struct dma_cont *d = &dma_controllers[nchan > 3];
+
+ qemu_irq_pulse(*d->cpu_request_exit);
+}
+
+static void dma_reset(void *opaque)
+{
+ struct dma_cont *d = opaque;
+ write_cont(d, (0x05 << d->dshift), 0, 1);
+}
+
+static int dma_phony_handler (void *opaque, int nchan, int dma_pos, int dma_len)
+{
+ dolog ("unregistered DMA channel used nchan=%d dma_pos=%d dma_len=%d\n",
+ nchan, dma_pos, dma_len);
+ return dma_pos;
+}
+
+
+static const MemoryRegionOps channel_io_ops = {
+ .read = read_chan,
+ .write = write_chan,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .impl = {
+ .min_access_size = 1,
+ .max_access_size = 1,
+ },
+};
+
+/* IOport from page_base */
+static const MemoryRegionPortio page_portio_list[] = {
+ { 0x01, 3, 1, .write = write_page, .read = read_page, },
+ { 0x07, 1, 1, .write = write_page, .read = read_page, },
+ PORTIO_END_OF_LIST(),
+};
+
+/* IOport from pageh_base */
+static const MemoryRegionPortio pageh_portio_list[] = {
+ { 0x01, 3, 1, .write = write_pageh, .read = read_pageh, },
+ { 0x07, 3, 1, .write = write_pageh, .read = read_pageh, },
+ PORTIO_END_OF_LIST(),
+};
+
+static const MemoryRegionOps cont_io_ops = {
+ .read = read_cont,
+ .write = write_cont,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .impl = {
+ .min_access_size = 1,
+ .max_access_size = 1,
+ },
+};
+
+/* dshift = 0: 8 bit DMA, 1 = 16 bit DMA */
+static void dma_init2(struct dma_cont *d, int base, int dshift,
+ int page_base, int pageh_base,
+ qemu_irq *cpu_request_exit)
+{
+ int i;
+
+ d->dshift = dshift;
+ d->cpu_request_exit = cpu_request_exit;
+
+ memory_region_init_io(&d->channel_io, &channel_io_ops, d,
+ "dma-chan", 8 << d->dshift);
+ memory_region_add_subregion(isa_address_space_io(NULL),
+ base, &d->channel_io);
+
+ isa_register_portio_list(NULL, page_base, page_portio_list, d,
+ "dma-page");
+ if (pageh_base >= 0) {
+ isa_register_portio_list(NULL, pageh_base, pageh_portio_list, d,
+ "dma-pageh");
+ }
+
+ memory_region_init_io(&d->cont_io, &cont_io_ops, d, "dma-cont",
+ 8 << d->dshift);
+ memory_region_add_subregion(isa_address_space_io(NULL),
+ base + (8 << d->dshift), &d->cont_io);
+
+ qemu_register_reset(dma_reset, d);
+ dma_reset(d);
+ for (i = 0; i < ARRAY_SIZE (d->regs); ++i) {
+ d->regs[i].transfer_handler = dma_phony_handler;
+ }
+}
+
+static const VMStateDescription vmstate_dma_regs = {
+ .name = "dma_regs",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .fields = (VMStateField []) {
+ VMSTATE_INT32_ARRAY(now, struct dma_regs, 2),
+ VMSTATE_UINT16_ARRAY(base, struct dma_regs, 2),
+ VMSTATE_UINT8(mode, struct dma_regs),
+ VMSTATE_UINT8(page, struct dma_regs),
+ VMSTATE_UINT8(pageh, struct dma_regs),
+ VMSTATE_UINT8(dack, struct dma_regs),
+ VMSTATE_UINT8(eop, struct dma_regs),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static int dma_post_load(void *opaque, int version_id)
+{
+ DMA_run();
+
+ return 0;
+}
+
+static const VMStateDescription vmstate_dma = {
+ .name = "dma",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .post_load = dma_post_load,
+ .fields = (VMStateField []) {
+ VMSTATE_UINT8(command, struct dma_cont),
+ VMSTATE_UINT8(mask, struct dma_cont),
+ VMSTATE_UINT8(flip_flop, struct dma_cont),
+ VMSTATE_INT32(dshift, struct dma_cont),
+ VMSTATE_STRUCT_ARRAY(regs, struct dma_cont, 4, 1, vmstate_dma_regs, struct dma_regs),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+void DMA_init(int high_page_enable, qemu_irq *cpu_request_exit)
+{
+ dma_init2(&dma_controllers[0], 0x00, 0, 0x80,
+ high_page_enable ? 0x480 : -1, cpu_request_exit);
+ dma_init2(&dma_controllers[1], 0xc0, 1, 0x88,
+ high_page_enable ? 0x488 : -1, cpu_request_exit);
+ vmstate_register (NULL, 0, &vmstate_dma, &dma_controllers[0]);
+ vmstate_register (NULL, 1, &vmstate_dma, &dma_controllers[1]);
+
+ dma_bh = qemu_bh_new(DMA_run_bh, NULL);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 19:21:39 +0000