From: Grégory ESTRADE <gregory.estr...@gmail.com>
At present, all DMA transfers complete inline (so a looping descriptor
queue will lock up the device). We also do not model pause/abort,
arbitrarion/priority, or debug features.
Signed-off-by: Grégory ESTRADE <gregory.estr...@gmail.com>
[AB: implement 2D mode, cleanup/refactoring for upstream submission]
Signed-off-by: Andrew Baumann <andrew.baum...@microsoft.com>
Reviewed-by: Peter Maydell <peter.mayd...@linaro.org>
---
Notes:
v2:
* avoid ldl_phys/stl_phys
* compute address of channel structure only after asserting its validity
* correctly implement per-channel reset and abort bits
* set channel paused bit when completing DMA
hw/arm/bcm2835_peripherals.c | 26 +++
hw/dma/Makefile.objs | 1 +
hw/dma/bcm2835_dma.c | 408 +++++++++++++++++++++++++++++++++++
include/hw/arm/bcm2835_peripherals.h | 2 +
include/hw/dma/bcm2835_dma.h | 47 ++++
5 files changed, 484 insertions(+)
create mode 100644 hw/dma/bcm2835_dma.c
create mode 100644 include/hw/dma/bcm2835_dma.h
diff --git a/hw/arm/bcm2835_peripherals.c b/hw/arm/bcm2835_peripherals.c
index 4d74a18..8099a8a 100644
--- a/hw/arm/bcm2835_peripherals.c
+++ b/hw/arm/bcm2835_peripherals.c
@@ -88,6 +88,14 @@ static void bcm2835_peripherals_init(Object *obj)
object_initialize(&s->sdhci, sizeof(s->sdhci), TYPE_SYSBUS_SDHCI);
object_property_add_child(obj, "sdhci", OBJECT(&s->sdhci), NULL);
qdev_set_parent_bus(DEVICE(&s->sdhci), sysbus_get_default());
+
+ /* DMA Channels */
+ object_initialize(&s->dma, sizeof(s->dma), TYPE_BCM2835_DMA);
+ object_property_add_child(obj, "dma", OBJECT(&s->dma), NULL);
+ qdev_set_parent_bus(DEVICE(&s->dma), sysbus_get_default());
+
+ object_property_add_const_link(OBJECT(&s->dma), "dma-mr",
+ OBJECT(&s->gpu_bus_mr), &error_abort);
}
static void bcm2835_peripherals_realize(DeviceState *dev, Error **errp)
@@ -258,6 +266,24 @@ static void bcm2835_peripherals_realize(DeviceState *dev,
Error **errp)
return;
}
+ /* DMA Channels */
+ object_property_set_bool(OBJECT(&s->dma), true, "realized", &err);
+ if (err) {
+ error_propagate(errp, err);
+ return;
+ }
+
+ memory_region_add_subregion(&s->peri_mr, DMA_OFFSET,
+ sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->dma), 0));
+ memory_region_add_subregion(&s->peri_mr, DMA15_OFFSET,
+ sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->dma), 1));
+
+ for (n = 0; n <= 12; n++) {
+ sysbus_connect_irq(SYS_BUS_DEVICE(&s->dma), n,
+ qdev_get_gpio_in_named(DEVICE(&s->ic),
+ BCM2835_IC_GPU_IRQ,
+ INTERRUPT_DMA0 + n));
+ }
}
static void bcm2835_peripherals_class_init(ObjectClass *oc, void *data)
diff --git a/hw/dma/Makefile.objs b/hw/dma/Makefile.objs
index 0e65ed0..a1abbcf 100644
--- a/hw/dma/Makefile.objs
+++ b/hw/dma/Makefile.objs
@@ -11,3 +11,4 @@ common-obj-$(CONFIG_SUN4M) += sun4m_iommu.o
obj-$(CONFIG_OMAP) += omap_dma.o soc_dma.o
obj-$(CONFIG_PXA2XX) += pxa2xx_dma.o
+obj-$(CONFIG_RASPI) += bcm2835_dma.o
diff --git a/hw/dma/bcm2835_dma.c b/hw/dma/bcm2835_dma.c
new file mode 100644
index 0000000..c7ce4e4
--- /dev/null
+++ b/hw/dma/bcm2835_dma.c
@@ -0,0 +1,408 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/dma/bcm2835_dma.h"
+
+/* DMA CS Control and Status bits */
+#define BCM2708_DMA_ACTIVE (1 << 0)
+#define BCM2708_DMA_END (1 << 1) /* GE */
+#define BCM2708_DMA_INT (1 << 2)
+#define BCM2708_DMA_ISPAUSED (1 << 4) /* Pause requested or not active */
+#define BCM2708_DMA_ISHELD (1 << 5) /* Is held by DREQ flow control */
+#define BCM2708_DMA_ERR (1 << 8)
+#define BCM2708_DMA_ABORT (1 << 30) /* stop current CB, go to next, WO */
+#define BCM2708_DMA_RESET (1 << 31) /* WO, self clearing */
+
+/* DMA control block "info" field bits */
+#define BCM2708_DMA_INT_EN (1 << 0)
+#define BCM2708_DMA_TDMODE (1 << 1)
+#define BCM2708_DMA_WAIT_RESP (1 << 3)
+#define BCM2708_DMA_D_INC (1 << 4)
+#define BCM2708_DMA_D_WIDTH (1 << 5)
+#define BCM2708_DMA_D_DREQ (1 << 6)
+#define BCM2708_DMA_D_IGNORE (1 << 7)
+#define BCM2708_DMA_S_INC (1 << 8)
+#define BCM2708_DMA_S_WIDTH (1 << 9)
+#define BCM2708_DMA_S_DREQ (1 << 10)
+#define BCM2708_DMA_S_IGNORE (1 << 11)
+
+/* Register offsets */
+#define BCM2708_DMA_CS 0x00 /* Control and Status */
+#define BCM2708_DMA_ADDR 0x04 /* Control block address */
+/* the current control block appears in the following registers - read only */
+#define BCM2708_DMA_INFO 0x08
+#define BCM2708_DMA_SOURCE_AD 0x0c
+#define BCM2708_DMA_DEST_AD 0x10
+#define BCM2708_DMA_TXFR_LEN 0x14
+#define BCM2708_DMA_STRIDE 0x18
+#define BCM2708_DMA_NEXTCB 0x1C
+#define BCM2708_DMA_DEBUG 0x20
+
+#define BCM2708_DMA_INT_STATUS 0xfe0 /* Interrupt status of each channel */
+#define BCM2708_DMA_ENABLE 0xff0 /* Global enable bits for each channel */
+
+#define BCM2708_DMA_CS_RW_MASK 0x30ff0001 /* All RW bits in DMA_CS */
+
+static void bcm2835_dma_update(BCM2835DMAState *s, unsigned c)
+{
+ BCM2835DMAChan *ch = &s->chan[c];
+ uint32_t data, xlen, ylen;
+ int16_t dst_stride, src_stride;
+
+ if (!(s->enable & (1 << c))) {
+ return;
+ }
+
+ while ((s->enable & (1 << c)) && (ch->conblk_ad != 0)) {
+ /* CB fetch */
+ ch->ti = ldl_le_phys(&s->dma_as, ch->conblk_ad);
+ ch->source_ad = ldl_le_phys(&s->dma_as, ch->conblk_ad + 4);
+ ch->dest_ad = ldl_le_phys(&s->dma_as, ch->conblk_ad + 8);
+ ch->txfr_len = ldl_le_phys(&s->dma_as, ch->conblk_ad + 12);
+ ch->stride = ldl_le_phys(&s->dma_as, ch->conblk_ad + 16);
+ ch->nextconbk = ldl_le_phys(&s->dma_as, ch->conblk_ad + 20);
+
+ if (ch->ti & BCM2708_DMA_TDMODE) {
+ /* 2D transfer mode */
+ ylen = (ch->txfr_len >> 16) & 0x3fff;
+ xlen = ch->txfr_len & 0xffff;
+ dst_stride = ch->stride >> 16;
+ src_stride = ch->stride & 0xffff;
+ } else {
+ ylen = 1;
+ xlen = ch->txfr_len;
+ dst_stride = 0;
+ src_stride = 0;
+ }
+
+ while (ylen != 0) {
+ /* Normal transfer mode */
+ while (xlen != 0) {
+ if (ch->ti & BCM2708_DMA_S_IGNORE) {
+ /* Ignore reads */
+ data = 0;
+ } else {
+ data = ldl_le_phys(&s->dma_as, ch->source_ad);
+ }
+ if (ch->ti & BCM2708_DMA_S_INC) {
+ ch->source_ad += 4;
+ }
+
+ if (ch->ti & BCM2708_DMA_D_IGNORE) {
+ /* Ignore writes */
+ } else {
+ stl_le_phys(&s->dma_as, ch->dest_ad, data);
+ }
+ if (ch->ti & BCM2708_DMA_D_INC) {
+ ch->dest_ad += 4;
+ }
+
+ /* update remaining transfer length */
+ xlen -= 4;
+ if (ch->ti & BCM2708_DMA_TDMODE) {
+ ch->txfr_len = (ylen << 16) | xlen;
+ } else {
+ ch->txfr_len = xlen;
+ }
+ }
+
+ if (--ylen != 0) {
+ ch->source_ad += src_stride;
+ ch->dest_ad += dst_stride;
+ }
+ }
+ ch->cs |= BCM2708_DMA_END;
+ if (ch->ti & BCM2708_DMA_INT_EN) {
+ ch->cs |= BCM2708_DMA_INT;
+ s->int_status |= (1 << c);
+ qemu_set_irq(ch->irq, 1);
+ }
+
+ /* Process next CB */
+ ch->conblk_ad = ch->nextconbk;
+ }
+
+ ch->cs &= ~BCM2708_DMA_ACTIVE;
+ ch->cs |= BCM2708_DMA_ISPAUSED;
+}
+
+static void bcm2835_dma_chan_reset(BCM2835DMAChan *ch)
+{
+ ch->cs = 0;
+ ch->conblk_ad = 0;
+}
+
+static uint64_t bcm2835_dma_read(BCM2835DMAState *s, hwaddr offset,
+ unsigned size, unsigned c)
+{
+ BCM2835DMAChan *ch;
+ uint32_t res = 0;
+
+ assert(size == 4);
+ assert(c < BCM2835_DMA_NCHANS);
+
+ ch = &s->chan[c];
+
+ switch (offset) {
+ case BCM2708_DMA_CS:
+ res = ch->cs;
+ break;
+ case BCM2708_DMA_ADDR:
+ res = ch->conblk_ad;
+ break;
+ case BCM2708_DMA_INFO:
+ res = ch->ti;
+ break;
+ case BCM2708_DMA_SOURCE_AD:
+ res = ch->source_ad;
+ break;
+ case BCM2708_DMA_DEST_AD:
+ res = ch->dest_ad;
+ break;
+ case BCM2708_DMA_TXFR_LEN:
+ res = ch->txfr_len;
+ break;
+ case BCM2708_DMA_STRIDE:
+ res = ch->stride;
+ break;
+ case BCM2708_DMA_NEXTCB:
+ res = ch->nextconbk;
+ break;
+ case BCM2708_DMA_DEBUG:
+ res = ch->debug;
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+ __func__, offset);
+ break;
+ }
+ return res;
+}
+
+static void bcm2835_dma_write(BCM2835DMAState *s, hwaddr offset,
+ uint64_t value, unsigned size, unsigned c)
+{
+ BCM2835DMAChan *ch;
+ uint32_t oldcs;
+
+ assert(size == 4);
+ assert(c < BCM2835_DMA_NCHANS);
+
+ ch = &s->chan[c];
+
+ switch (offset) {
+ case BCM2708_DMA_CS:
+ oldcs = ch->cs;
+ if (value & BCM2708_DMA_RESET) {
+ bcm2835_dma_chan_reset(ch);
+ }
+ if (value & BCM2708_DMA_ABORT) {
+ /* abort is a no-op, since we always run to completion */
+ }
+ if (value & BCM2708_DMA_END) {
+ ch->cs &= ~BCM2708_DMA_END;
+ }
+ if (value & BCM2708_DMA_INT) {
+ ch->cs &= ~BCM2708_DMA_INT;
+ s->int_status &= ~(1 << c);
+ qemu_set_irq(ch->irq, 0);
+ }
+ ch->cs &= ~BCM2708_DMA_CS_RW_MASK;
+ ch->cs |= (value & BCM2708_DMA_CS_RW_MASK);
+ if (!(oldcs & BCM2708_DMA_ACTIVE) && (ch->cs & BCM2708_DMA_ACTIVE)) {
+ bcm2835_dma_update(s, c);
+ }
+ break;
+ case BCM2708_DMA_ADDR:
+ ch->conblk_ad = value;
+ break;
+ case BCM2708_DMA_DEBUG:
+ ch->debug = value;
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+ __func__, offset);
+ break;
+ }
+}
+
+static uint64_t bcm2835_dma0_read(void *opaque, hwaddr offset, unsigned size)
+{
+ BCM2835DMAState *s = opaque;
+
+ if (offset < 0xf00) {
+ return bcm2835_dma_read(s, (offset & 0xff), size, (offset >> 8) & 0xf);
+ } else {
+ switch (offset) {
+ case BCM2708_DMA_INT_STATUS:
+ return s->int_status;
+ case BCM2708_DMA_ENABLE:
+ return s->enable;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+ __func__, offset);
+ return 0;
+ }
+ }
+}
+
+static uint64_t bcm2835_dma15_read(void *opaque, hwaddr offset, unsigned size)
+{
+ return bcm2835_dma_read(opaque, (offset & 0xff), size, 15);
+}
+
+static void bcm2835_dma0_write(void *opaque, hwaddr offset, uint64_t value,
+ unsigned size)
+{
+ BCM2835DMAState *s = opaque;
+
+ if (offset < 0xf00) {
+ bcm2835_dma_write(s, (offset & 0xff), value, size, (offset >> 8) &
0xf);
+ } else {
+ switch (offset) {
+ case BCM2708_DMA_INT_STATUS:
+ break;
+ case BCM2708_DMA_ENABLE:
+ s->enable = (value & 0xffff);
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+ __func__, offset);
+ }
+ }
+
+}
+
+static void bcm2835_dma15_write(void *opaque, hwaddr offset, uint64_t value,
+ unsigned size)
+{
+ bcm2835_dma_write(opaque, (offset & 0xff), value, size, 15);
+}
+
+static const MemoryRegionOps bcm2835_dma0_ops = {
+ .read = bcm2835_dma0_read,
+ .write = bcm2835_dma0_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid.min_access_size = 4,
+ .valid.max_access_size = 4,
+};
+
+static const MemoryRegionOps bcm2835_dma15_ops = {
+ .read = bcm2835_dma15_read,
+ .write = bcm2835_dma15_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid.min_access_size = 4,
+ .valid.max_access_size = 4,
+};
+
+static const VMStateDescription vmstate_bcm2835_dma_chan = {
+ .name = TYPE_BCM2835_DMA "-chan",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(cs, BCM2835DMAChan),
+ VMSTATE_UINT32(conblk_ad, BCM2835DMAChan),
+ VMSTATE_UINT32(ti, BCM2835DMAChan),
+ VMSTATE_UINT32(source_ad, BCM2835DMAChan),
+ VMSTATE_UINT32(dest_ad, BCM2835DMAChan),
+ VMSTATE_UINT32(txfr_len, BCM2835DMAChan),
+ VMSTATE_UINT32(stride, BCM2835DMAChan),
+ VMSTATE_UINT32(nextconbk, BCM2835DMAChan),
+ VMSTATE_UINT32(debug, BCM2835DMAChan),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static const VMStateDescription vmstate_bcm2835_dma = {
+ .name = TYPE_BCM2835_DMA,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_STRUCT_ARRAY(chan, BCM2835DMAState, BCM2835_DMA_NCHANS, 1,
+ vmstate_bcm2835_dma_chan, BCM2835DMAChan),
+ VMSTATE_UINT32(int_status, BCM2835DMAState),
+ VMSTATE_UINT32(enable, BCM2835DMAState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void bcm2835_dma_init(Object *obj)
+{
+ BCM2835DMAState *s = BCM2835_DMA(obj);
+ int n;
+
+ /* DMA channels 0-14 occupy a contiguous block of IO memory, along
+ * with the global enable and interrupt status bits. Channel 15
+ * has the same register map, but is mapped at a discontiguous
+ * address in a separate IO block.
+ */
+ memory_region_init_io(&s->iomem0, OBJECT(s), &bcm2835_dma0_ops, s,
+ TYPE_BCM2835_DMA, 0x1000);
+ sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem0);
+
+ memory_region_init_io(&s->iomem15, OBJECT(s), &bcm2835_dma15_ops, s,
+ TYPE_BCM2835_DMA "-chan15", 0x100);
+ sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem15);
+
+ for (n = 0; n < 16; n++) {
+ sysbus_init_irq(SYS_BUS_DEVICE(s), &s->chan[n].irq);
+ }
+}
+
+static void bcm2835_dma_reset(DeviceState *dev)
+{
+ BCM2835DMAState *s = BCM2835_DMA(dev);
+ int n;
+
+ s->enable = 0xffff;
+ s->int_status = 0;
+ for (n = 0; n < BCM2835_DMA_NCHANS; n++) {
+ bcm2835_dma_chan_reset(&s->chan[n]);
+ }
+}
+
+static void bcm2835_dma_realize(DeviceState *dev, Error **errp)
+{
+ BCM2835DMAState *s = BCM2835_DMA(dev);
+ Error *err = NULL;
+ Object *obj;
+
+ obj = object_property_get_link(OBJECT(dev), "dma-mr", &err);
+ if (obj == NULL) {
+ error_setg(errp, "%s: required dma-mr link not found: %s",
+ __func__, error_get_pretty(err));
+ return;
+ }
+
+ s->dma_mr = MEMORY_REGION(obj);
+ address_space_init(&s->dma_as, s->dma_mr, NULL);
+
+ bcm2835_dma_reset(dev);
+}
+
+static void bcm2835_dma_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = bcm2835_dma_realize;
+ dc->reset = bcm2835_dma_reset;
+ dc->vmsd = &vmstate_bcm2835_dma;
+}
+
+static TypeInfo bcm2835_dma_info = {
+ .name = TYPE_BCM2835_DMA,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(BCM2835DMAState),
+ .class_init = bcm2835_dma_class_init,
+ .instance_init = bcm2835_dma_init,
+};
+
+static void bcm2835_dma_register_types(void)
+{
+ type_register_static(&bcm2835_dma_info);
+}
+
+type_init(bcm2835_dma_register_types)
diff --git a/include/hw/arm/bcm2835_peripherals.h
b/include/hw/arm/bcm2835_peripherals.h
index e19d360..e12ae37 100644
--- a/include/hw/arm/bcm2835_peripherals.h
+++ b/include/hw/arm/bcm2835_peripherals.h
@@ -16,6 +16,7 @@
#include "hw/sysbus.h"
#include "hw/char/bcm2835_aux.h"
#include "hw/display/bcm2835_fb.h"
+#include "hw/dma/bcm2835_dma.h"
#include "hw/intc/bcm2835_ic.h"
#include "hw/misc/bcm2835_property.h"
#include "hw/misc/bcm2835_mbox.h"
@@ -37,6 +38,7 @@ typedef struct BCM2835PeripheralState {
SysBusDevice *uart0;
BCM2835AuxState aux;
BCM2835FBState fb;
+ BCM2835DMAState dma;
BCM2835ICState ic;
BCM2835PropertyState property;
BCM2835MboxState mboxes;
diff --git a/include/hw/dma/bcm2835_dma.h b/include/hw/dma/bcm2835_dma.h
new file mode 100644
index 0000000..75312e2
--- /dev/null
+++ b/include/hw/dma/bcm2835_dma.h
@@ -0,0 +1,47 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ */
+
+#ifndef BCM2835_DMA_H
+#define BCM2835_DMA_H
+
+#include "qemu-common.h"
+#include "exec/address-spaces.h"
+#include "hw/sysbus.h"
+
+typedef struct {
+ uint32_t cs;
+ uint32_t conblk_ad;
+ uint32_t ti;
+ uint32_t source_ad;
+ uint32_t dest_ad;
+ uint32_t txfr_len;
+ uint32_t stride;
+ uint32_t nextconbk;
+ uint32_t debug;
+
+ qemu_irq irq;
+} BCM2835DMAChan;
+
+#define TYPE_BCM2835_DMA "bcm2835-dma"
+#define BCM2835_DMA(obj) \
+ OBJECT_CHECK(BCM2835DMAState, (obj), TYPE_BCM2835_DMA)
+
+#define BCM2835_DMA_NCHANS 16
+
+typedef struct {
+ /*< private >*/
+ SysBusDevice busdev;
+ /*< public >*/
+
+ MemoryRegion iomem0, iomem15;
+ MemoryRegion *dma_mr;
+ AddressSpace dma_as;
+
+ BCM2835DMAChan chan[BCM2835_DMA_NCHANS];
+ uint32_t int_status;
+ uint32_t enable;
+} BCM2835DMAState;
+
+#endif
--
2.7.0
