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-rw-r--r--hw/dma/sifive_pdma.c313
1 files changed, 313 insertions, 0 deletions
diff --git a/hw/dma/sifive_pdma.c b/hw/dma/sifive_pdma.c
new file mode 100644
index 0000000000..e1f6fedbda
--- /dev/null
+++ b/hw/dma/sifive_pdma.c
@@ -0,0 +1,313 @@
+/*
+ * SiFive Platform DMA emulation
+ *
+ * Copyright (c) 2020 Wind River Systems, Inc.
+ *
+ * Author:
+ * Bin Meng <bin.meng@windriver.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 or
+ * (at your option) version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/bitops.h"
+#include "qemu/log.h"
+#include "qapi/error.h"
+#include "hw/hw.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/sysbus.h"
+#include "migration/vmstate.h"
+#include "sysemu/dma.h"
+#include "hw/dma/sifive_pdma.h"
+
+#define DMA_CONTROL 0x000
+#define CONTROL_CLAIM BIT(0)
+#define CONTROL_RUN BIT(1)
+#define CONTROL_DONE_IE BIT(14)
+#define CONTROL_ERR_IE BIT(15)
+#define CONTROL_DONE BIT(30)
+#define CONTROL_ERR BIT(31)
+
+#define DMA_NEXT_CONFIG 0x004
+#define CONFIG_REPEAT BIT(2)
+#define CONFIG_ORDER BIT(3)
+#define CONFIG_WRSZ_SHIFT 24
+#define CONFIG_RDSZ_SHIFT 28
+#define CONFIG_SZ_MASK 0xf
+
+#define DMA_NEXT_BYTES 0x008
+#define DMA_NEXT_DST 0x010
+#define DMA_NEXT_SRC 0x018
+#define DMA_EXEC_CONFIG 0x104
+#define DMA_EXEC_BYTES 0x108
+#define DMA_EXEC_DST 0x110
+#define DMA_EXEC_SRC 0x118
+
+enum dma_chan_state {
+ DMA_CHAN_STATE_IDLE,
+ DMA_CHAN_STATE_STARTED,
+ DMA_CHAN_STATE_ERROR,
+ DMA_CHAN_STATE_DONE
+};
+
+static void sifive_pdma_run(SiFivePDMAState *s, int ch)
+{
+ uint64_t bytes = s->chan[ch].next_bytes;
+ uint64_t dst = s->chan[ch].next_dst;
+ uint64_t src = s->chan[ch].next_src;
+ uint32_t config = s->chan[ch].next_config;
+ int wsize, rsize, size;
+ uint8_t buf[64];
+ int n;
+
+ /* do nothing if bytes to transfer is zero */
+ if (!bytes) {
+ goto error;
+ }
+
+ /*
+ * The manual does not describe how the hardware behaviors when
+ * config.wsize and config.rsize are given different values.
+ * A common case is memory to memory DMA, and in this case they
+ * are normally the same. Abort if this expectation fails.
+ */
+ wsize = (config >> CONFIG_WRSZ_SHIFT) & CONFIG_SZ_MASK;
+ rsize = (config >> CONFIG_RDSZ_SHIFT) & CONFIG_SZ_MASK;
+ if (wsize != rsize) {
+ goto error;
+ }
+
+ /*
+ * Calculate the transaction size
+ *
+ * size field is base 2 logarithm of DMA transaction size,
+ * but there is an upper limit of 64 bytes per transaction.
+ */
+ size = wsize;
+ if (size > 6) {
+ size = 6;
+ }
+ size = 1 << size;
+
+ /* the bytes to transfer should be multiple of transaction size */
+ if (bytes % size) {
+ goto error;
+ }
+
+ /* indicate a DMA transfer is started */
+ s->chan[ch].state = DMA_CHAN_STATE_STARTED;
+ s->chan[ch].control &= ~CONTROL_DONE;
+ s->chan[ch].control &= ~CONTROL_ERR;
+
+ /* load the next_ registers into their exec_ counterparts */
+ s->chan[ch].exec_config = config;
+ s->chan[ch].exec_bytes = bytes;
+ s->chan[ch].exec_dst = dst;
+ s->chan[ch].exec_src = src;
+
+ for (n = 0; n < bytes / size; n++) {
+ cpu_physical_memory_read(s->chan[ch].exec_src, buf, size);
+ cpu_physical_memory_write(s->chan[ch].exec_dst, buf, size);
+ s->chan[ch].exec_src += size;
+ s->chan[ch].exec_dst += size;
+ s->chan[ch].exec_bytes -= size;
+ }
+
+ /* indicate a DMA transfer is done */
+ s->chan[ch].state = DMA_CHAN_STATE_DONE;
+ s->chan[ch].control &= ~CONTROL_RUN;
+ s->chan[ch].control |= CONTROL_DONE;
+
+ /* reload exec_ registers if repeat is required */
+ if (s->chan[ch].next_config & CONFIG_REPEAT) {
+ s->chan[ch].exec_bytes = bytes;
+ s->chan[ch].exec_dst = dst;
+ s->chan[ch].exec_src = src;
+ }
+
+ return;
+
+error:
+ s->chan[ch].state = DMA_CHAN_STATE_ERROR;
+ s->chan[ch].control |= CONTROL_ERR;
+ return;
+}
+
+static inline void sifive_pdma_update_irq(SiFivePDMAState *s, int ch)
+{
+ bool done_ie, err_ie;
+
+ done_ie = !!(s->chan[ch].control & CONTROL_DONE_IE);
+ err_ie = !!(s->chan[ch].control & CONTROL_ERR_IE);
+
+ if (done_ie && (s->chan[ch].control & CONTROL_DONE)) {
+ qemu_irq_raise(s->irq[ch * 2]);
+ } else {
+ qemu_irq_lower(s->irq[ch * 2]);
+ }
+
+ if (err_ie && (s->chan[ch].control & CONTROL_ERR)) {
+ qemu_irq_raise(s->irq[ch * 2 + 1]);
+ } else {
+ qemu_irq_lower(s->irq[ch * 2 + 1]);
+ }
+
+ s->chan[ch].state = DMA_CHAN_STATE_IDLE;
+}
+
+static uint64_t sifive_pdma_read(void *opaque, hwaddr offset, unsigned size)
+{
+ SiFivePDMAState *s = opaque;
+ int ch = SIFIVE_PDMA_CHAN_NO(offset);
+ uint64_t val = 0;
+
+ if (ch >= SIFIVE_PDMA_CHANS) {
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Invalid channel no %d\n",
+ __func__, ch);
+ return 0;
+ }
+
+ offset &= 0xfff;
+ switch (offset) {
+ case DMA_CONTROL:
+ val = s->chan[ch].control;
+ break;
+ case DMA_NEXT_CONFIG:
+ val = s->chan[ch].next_config;
+ break;
+ case DMA_NEXT_BYTES:
+ val = s->chan[ch].next_bytes;
+ break;
+ case DMA_NEXT_DST:
+ val = s->chan[ch].next_dst;
+ break;
+ case DMA_NEXT_SRC:
+ val = s->chan[ch].next_src;
+ break;
+ case DMA_EXEC_CONFIG:
+ val = s->chan[ch].exec_config;
+ break;
+ case DMA_EXEC_BYTES:
+ val = s->chan[ch].exec_bytes;
+ break;
+ case DMA_EXEC_DST:
+ val = s->chan[ch].exec_dst;
+ break;
+ case DMA_EXEC_SRC:
+ val = s->chan[ch].exec_src;
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIX "\n",
+ __func__, offset);
+ break;
+ }
+
+ return val;
+}
+
+static void sifive_pdma_write(void *opaque, hwaddr offset,
+ uint64_t value, unsigned size)
+{
+ SiFivePDMAState *s = opaque;
+ int ch = SIFIVE_PDMA_CHAN_NO(offset);
+
+ if (ch >= SIFIVE_PDMA_CHANS) {
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Invalid channel no %d\n",
+ __func__, ch);
+ return;
+ }
+
+ offset &= 0xfff;
+ switch (offset) {
+ case DMA_CONTROL:
+ s->chan[ch].control = value;
+
+ if (value & CONTROL_RUN) {
+ sifive_pdma_run(s, ch);
+ }
+
+ sifive_pdma_update_irq(s, ch);
+ break;
+ case DMA_NEXT_CONFIG:
+ s->chan[ch].next_config = value;
+ break;
+ case DMA_NEXT_BYTES:
+ s->chan[ch].next_bytes = value;
+ break;
+ case DMA_NEXT_DST:
+ s->chan[ch].next_dst = value;
+ break;
+ case DMA_NEXT_SRC:
+ s->chan[ch].next_src = value;
+ break;
+ case DMA_EXEC_CONFIG:
+ case DMA_EXEC_BYTES:
+ case DMA_EXEC_DST:
+ case DMA_EXEC_SRC:
+ /* these are read-only registers */
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIX "\n",
+ __func__, offset);
+ break;
+ }
+}
+
+static const MemoryRegionOps sifive_pdma_ops = {
+ .read = sifive_pdma_read,
+ .write = sifive_pdma_write,
+ .endianness = DEVICE_LITTLE_ENDIAN,
+ /* there are 32-bit and 64-bit wide registers */
+ .impl = {
+ .min_access_size = 4,
+ .max_access_size = 8,
+ }
+};
+
+static void sifive_pdma_realize(DeviceState *dev, Error **errp)
+{
+ SiFivePDMAState *s = SIFIVE_PDMA(dev);
+ int i;
+
+ memory_region_init_io(&s->iomem, OBJECT(dev), &sifive_pdma_ops, s,
+ TYPE_SIFIVE_PDMA, SIFIVE_PDMA_REG_SIZE);
+ sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->iomem);
+
+ for (i = 0; i < SIFIVE_PDMA_IRQS; i++) {
+ sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[i]);
+ }
+}
+
+static void sifive_pdma_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->desc = "SiFive Platform DMA controller";
+ dc->realize = sifive_pdma_realize;
+}
+
+static const TypeInfo sifive_pdma_info = {
+ .name = TYPE_SIFIVE_PDMA,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(SiFivePDMAState),
+ .class_init = sifive_pdma_class_init,
+};
+
+static void sifive_pdma_register_types(void)
+{
+ type_register_static(&sifive_pdma_info);
+}
+
+type_init(sifive_pdma_register_types)
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