This adds the system mailboxes which are used to communicate with a
number of GPU peripherals on Pi/Pi2.
Reviewed-by: Peter Crosthwaite <crosthwaite.pe...@gmail.com>
Signed-off-by: Andrew Baumann <andrew.baum...@microsoft.com>
---
Notes:
v5:
* minor style tweaks only
v3:
* #define register offsets
* rename mbox_init -> mbox_reset
* s/_/-/ in property and type names
* avoid hw_error
* minor style tweaks
v2:
* renamed bcm2835_sbm to bcm2835_mbox
* dropped bcm2835_arm_control.h (needed defs moved to bcm2835_mbox.c)
* documented use of private address space through defines in
bcm2835_mbox_defs.h
* remove unused fields from BCM2835Mbox
* s/int/bool/ where appropriate
* cleaned up logic in _update and _mbox_update_status for
clarity/simplicity
* added vmstate
* misc cleanup
default-configs/arm-softmmu.mak | 1 +
hw/misc/Makefile.objs | 1 +
hw/misc/bcm2835_mbox.c | 333 ++++++++++++++++++++++++++++++++++++
include/hw/misc/bcm2835_mbox.h | 38 ++++
include/hw/misc/bcm2835_mbox_defs.h | 27 +++
5 files changed, 400 insertions(+)
create mode 100644 hw/misc/bcm2835_mbox.c
create mode 100644 include/hw/misc/bcm2835_mbox.h
create mode 100644 include/hw/misc/bcm2835_mbox_defs.h
diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
index d9b90a5..a9f82a1 100644
--- a/default-configs/arm-softmmu.mak
+++ b/default-configs/arm-softmmu.mak
@@ -79,6 +79,7 @@ CONFIG_TUSB6010=y
CONFIG_IMX=y
CONFIG_MAINSTONE=y
CONFIG_NSERIES=y
+CONFIG_RASPI=y
CONFIG_REALVIEW=y
CONFIG_ZAURUS=y
CONFIG_ZYNQ=y
diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
index d4765c2..d0ea105 100644
--- a/hw/misc/Makefile.objs
+++ b/hw/misc/Makefile.objs
@@ -36,6 +36,7 @@ obj-$(CONFIG_OMAP) += omap_gpmc.o
obj-$(CONFIG_OMAP) += omap_l4.o
obj-$(CONFIG_OMAP) += omap_sdrc.o
obj-$(CONFIG_OMAP) += omap_tap.o
+obj-$(CONFIG_RASPI) += bcm2835_mbox.o
obj-$(CONFIG_SLAVIO) += slavio_misc.o
obj-$(CONFIG_ZYNQ) += zynq_slcr.o
obj-$(CONFIG_ZYNQ) += zynq-xadc.o
diff --git a/hw/misc/bcm2835_mbox.c b/hw/misc/bcm2835_mbox.c
new file mode 100644
index 0000000..df1d6e6
--- /dev/null
+++ b/hw/misc/bcm2835_mbox.c
@@ -0,0 +1,333 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ *
+ * This file models the system mailboxes, which are used for
+ * communication with low-bandwidth GPU peripherals. Refs:
+ * https://github.com/raspberrypi/firmware/wiki/Mailboxes
+ * https://github.com/raspberrypi/firmware/wiki/Accessing-mailboxes
+ */
+
+#include "hw/misc/bcm2835_mbox.h"
+
+#define MAIL0_PEEK 0x90
+#define MAIL0_SENDER 0x94
+#define MAIL1_STATUS 0xb8
+
+/* Mailbox status register */
+#define MAIL0_STATUS 0x98
+#define ARM_MS_FULL 0x80000000
+#define ARM_MS_EMPTY 0x40000000
+#define ARM_MS_LEVEL 0x400000FF /* Max. value depends on mailbox depth */
+
+/* MAILBOX config/status register */
+#define MAIL0_CONFIG 0x9c
+/* ANY write to this register clears the error bits! */
+#define ARM_MC_IHAVEDATAIRQEN 0x00000001 /* mbox irq enable: has data */
+#define ARM_MC_IHAVESPACEIRQEN 0x00000002 /* mbox irq enable: has space */
+#define ARM_MC_OPPISEMPTYIRQEN 0x00000004 /* mbox irq enable: Opp is empty */
+#define ARM_MC_MAIL_CLEAR 0x00000008 /* mbox clear write 1, then 0 */
+#define ARM_MC_IHAVEDATAIRQPEND 0x00000010 /* mbox irq pending: has space */
+#define ARM_MC_IHAVESPACEIRQPEND 0x00000020 /* mbox irq pending: Opp is empty
*/
+#define ARM_MC_OPPISEMPTYIRQPEND 0x00000040 /* mbox irq pending */
+/* Bit 7 is unused */
+#define ARM_MC_ERRNOOWN 0x00000100 /* error : none owner read from mailbox */
+#define ARM_MC_ERROVERFLW 0x00000200 /* error : write to fill mailbox */
+#define ARM_MC_ERRUNDRFLW 0x00000400 /* error : read from empty mailbox */
+
+static void mbox_update_status(BCM2835Mbox *mb)
+{
+ mb->status &= ~(ARM_MS_EMPTY | ARM_MS_FULL);
+ if (mb->count == 0) {
+ mb->status |= ARM_MS_EMPTY;
+ } else if (mb->count == MBOX_SIZE) {
+ mb->status |= ARM_MS_FULL;
+ }
+}
+
+static void mbox_reset(BCM2835Mbox *mb)
+{
+ int n;
+
+ mb->count = 0;
+ mb->config = 0;
+ for (n = 0; n < MBOX_SIZE; n++) {
+ mb->reg[n] = MBOX_INVALID_DATA;
+ }
+ mbox_update_status(mb);
+}
+
+static uint32_t mbox_pull(BCM2835Mbox *mb, int index)
+{
+ int n;
+ uint32_t val;
+
+ assert(mb->count > 0);
+ assert(index < mb->count);
+
+ val = mb->reg[index];
+ for (n = index + 1; n < mb->count; n++) {
+ mb->reg[n - 1] = mb->reg[n];
+ }
+ mb->count--;
+ mb->reg[mb->count] = MBOX_INVALID_DATA;
+
+ mbox_update_status(mb);
+
+ return val;
+}
+
+static void mbox_push(BCM2835Mbox *mb, uint32_t val)
+{
+ assert(mb->count < MBOX_SIZE);
+ mb->reg[mb->count++] = val;
+ mbox_update_status(mb);
+}
+
+static void bcm2835_mbox_update(BCM2835MboxState *s)
+{
+ uint32_t value;
+ bool set;
+ int n;
+
+ s->mbox_irq_disabled = true;
+
+ /* Get pending responses and put them in the vc->arm mbox,
+ * as long as it's not full
+ */
+ for (n = 0; n < MBOX_CHAN_COUNT; n++) {
+ while (s->available[n] && !(s->mbox[0].status & ARM_MS_FULL)) {
+ value = ldl_phys(&s->mbox_as, n << MBOX_AS_CHAN_SHIFT);
+ assert(value != MBOX_INVALID_DATA); /* Pending interrupt but no
data */
+ mbox_push(&s->mbox[0], value);
+ }
+ }
+
+ /* TODO (?): Try to push pending requests from the arm->vc mbox */
+
+ /* Re-enable calls from the IRQ routine */
+ s->mbox_irq_disabled = false;
+
+ /* Update ARM IRQ status */
+ set = false;
+ s->mbox[0].config &= ~ARM_MC_IHAVEDATAIRQPEND;
+ if (!(s->mbox[0].status & ARM_MS_EMPTY)) {
+ s->mbox[0].config |= ARM_MC_IHAVEDATAIRQPEND;
+ if (s->mbox[0].config & ARM_MC_IHAVEDATAIRQEN) {
+ set = true;
+ }
+ }
+ qemu_set_irq(s->arm_irq, set);
+}
+
+static void bcm2835_mbox_set_irq(void *opaque, int irq, int level)
+{
+ BCM2835MboxState *s = opaque;
+
+ s->available[irq] = level;
+
+ /* avoid recursively calling bcm2835_mbox_update when the interrupt
+ * status changes due to the ldl_phys call within that function
+ */
+ if (!s->mbox_irq_disabled) {
+ bcm2835_mbox_update(s);
+ }
+}
+
+static uint64_t bcm2835_mbox_read(void *opaque, hwaddr offset, unsigned size)
+{
+ BCM2835MboxState *s = opaque;
+ uint32_t res = 0;
+
+ offset &= 0xff;
+
+ switch (offset) {
+ case 0x80 ... 0x8c: /* MAIL0_READ */
+ if (s->mbox[0].status & ARM_MS_EMPTY) {
+ res = MBOX_INVALID_DATA;
+ } else {
+ res = mbox_pull(&s->mbox[0], 0);
+ }
+ break;
+
+ case MAIL0_PEEK:
+ res = s->mbox[0].reg[0];
+ break;
+
+ case MAIL0_SENDER:
+ break;
+
+ case MAIL0_STATUS:
+ res = s->mbox[0].status;
+ break;
+
+ case MAIL0_CONFIG:
+ res = s->mbox[0].config;
+ break;
+
+ case MAIL1_STATUS:
+ res = s->mbox[1].status;
+ break;
+
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+ __func__, offset);
+ return 0;
+ }
+
+ bcm2835_mbox_update(s);
+
+ return res;
+}
+
+static void bcm2835_mbox_write(void *opaque, hwaddr offset,
+ uint64_t value, unsigned size)
+{
+ BCM2835MboxState *s = opaque;
+ hwaddr childaddr;
+ uint8_t ch;
+
+ offset &= 0xff;
+
+ switch (offset) {
+ case MAIL0_SENDER:
+ break;
+
+ case MAIL0_CONFIG:
+ s->mbox[0].config &= ~ARM_MC_IHAVEDATAIRQEN;
+ s->mbox[0].config |= value & ARM_MC_IHAVEDATAIRQEN;
+ break;
+
+ case 0xa0 ... 0xac: /* MAIL1_WRITE */
+ if (s->mbox[1].status & ARM_MS_FULL) {
+ /* Mailbox full */
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: mailbox full\n", __func__);
+ } else {
+ ch = value & 0xf;
+ if (ch < MBOX_CHAN_COUNT) {
+ childaddr = ch << MBOX_AS_CHAN_SHIFT;
+ if (ldl_phys(&s->mbox_as, childaddr + MBOX_AS_PENDING)) {
+ /* Child busy, push delayed. Push it in the arm->vc mbox */
+ mbox_push(&s->mbox[1], value);
+ } else {
+ /* Push it directly to the child device */
+ stl_phys(&s->mbox_as, childaddr, value);
+ }
+ } else {
+ /* Invalid channel number */
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid channel %u\n",
+ __func__, ch);
+ }
+ }
+ break;
+
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+ __func__, offset);
+ return;
+ }
+
+ bcm2835_mbox_update(s);
+}
+
+static const MemoryRegionOps bcm2835_mbox_ops = {
+ .read = bcm2835_mbox_read,
+ .write = bcm2835_mbox_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+ .valid.min_access_size = 4,
+ .valid.max_access_size = 4,
+};
+
+/* vmstate of a single mailbox */
+static const VMStateDescription vmstate_bcm2835_mbox_box = {
+ .name = TYPE_BCM2835_MBOX "_box",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32_ARRAY(reg, BCM2835Mbox, MBOX_SIZE),
+ VMSTATE_UINT32(count, BCM2835Mbox),
+ VMSTATE_UINT32(status, BCM2835Mbox),
+ VMSTATE_UINT32(config, BCM2835Mbox),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+/* vmstate of the entire device */
+static const VMStateDescription vmstate_bcm2835_mbox = {
+ .name = TYPE_BCM2835_MBOX,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .minimum_version_id_old = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_BOOL_ARRAY(available, BCM2835MboxState, MBOX_CHAN_COUNT),
+ VMSTATE_STRUCT_ARRAY(mbox, BCM2835MboxState, 2, 1,
+ vmstate_bcm2835_mbox_box, BCM2835Mbox),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void bcm2835_mbox_init(Object *obj)
+{
+ BCM2835MboxState *s = BCM2835_MBOX(obj);
+
+ memory_region_init_io(&s->iomem, obj, &bcm2835_mbox_ops, s,
+ TYPE_BCM2835_MBOX, 0x400);
+ sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
+ sysbus_init_irq(SYS_BUS_DEVICE(s), &s->arm_irq);
+ qdev_init_gpio_in(DEVICE(s), bcm2835_mbox_set_irq, MBOX_CHAN_COUNT);
+}
+
+static void bcm2835_mbox_reset(DeviceState *dev)
+{
+ BCM2835MboxState *s = BCM2835_MBOX(dev);
+ int n;
+
+ mbox_reset(&s->mbox[0]);
+ mbox_reset(&s->mbox[1]);
+ s->mbox_irq_disabled = false;
+ for (n = 0; n < MBOX_CHAN_COUNT; n++) {
+ s->available[n] = false;
+ }
+}
+
+static void bcm2835_mbox_realize(DeviceState *dev, Error **errp)
+{
+ BCM2835MboxState *s = BCM2835_MBOX(dev);
+ Object *obj;
+ Error *err = NULL;
+
+ obj = object_property_get_link(OBJECT(dev), "mbox-mr", &err);
+ if (obj == NULL) {
+ error_setg(errp, "%s: required mbox-mr link not found: %s",
+ __func__, error_get_pretty(err));
+ return;
+ }
+
+ s->mbox_mr = MEMORY_REGION(obj);
+ address_space_init(&s->mbox_as, s->mbox_mr, NULL);
+ bcm2835_mbox_reset(dev);
+}
+
+static void bcm2835_mbox_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = bcm2835_mbox_realize;
+ dc->reset = bcm2835_mbox_reset;
+ dc->vmsd = &vmstate_bcm2835_mbox;
+}
+
+static TypeInfo bcm2835_mbox_info = {
+ .name = TYPE_BCM2835_MBOX,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(BCM2835MboxState),
+ .class_init = bcm2835_mbox_class_init,
+ .instance_init = bcm2835_mbox_init,
+};
+
+static void bcm2835_mbox_register_types(void)
+{
+ type_register_static(&bcm2835_mbox_info);
+}
+
+type_init(bcm2835_mbox_register_types)
diff --git a/include/hw/misc/bcm2835_mbox.h b/include/hw/misc/bcm2835_mbox.h
new file mode 100644
index 0000000..f4e9ff9
--- /dev/null
+++ b/include/hw/misc/bcm2835_mbox.h
@@ -0,0 +1,38 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ */
+
+#ifndef BCM2835_MBOX_H
+#define BCM2835_MBOX_H
+
+#include "bcm2835_mbox_defs.h"
+#include "hw/sysbus.h"
+#include "exec/address-spaces.h"
+
+#define TYPE_BCM2835_MBOX "bcm2835-mbox"
+#define BCM2835_MBOX(obj) \
+ OBJECT_CHECK(BCM2835MboxState, (obj), TYPE_BCM2835_MBOX)
+
+typedef struct {
+ uint32_t reg[MBOX_SIZE];
+ uint32_t count;
+ uint32_t status;
+ uint32_t config;
+} BCM2835Mbox;
+
+typedef struct {
+ /*< private >*/
+ SysBusDevice busdev;
+ /*< public >*/
+ MemoryRegion *mbox_mr;
+ AddressSpace mbox_as;
+ MemoryRegion iomem;
+ qemu_irq arm_irq;
+
+ bool mbox_irq_disabled;
+ bool available[MBOX_CHAN_COUNT];
+ BCM2835Mbox mbox[2];
+} BCM2835MboxState;
+
+#endif
diff --git a/include/hw/misc/bcm2835_mbox_defs.h
b/include/hw/misc/bcm2835_mbox_defs.h
new file mode 100644
index 0000000..a18e520
--- /dev/null
+++ b/include/hw/misc/bcm2835_mbox_defs.h
@@ -0,0 +1,27 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ */
+
+#ifndef BCM2835_MBOX_DEFS_H
+#define BCM2835_MBOX_DEFS_H
+
+/* Constants shared with the ARM identifying separate mailbox channels */
+#define MBOX_CHAN_POWER 0 /* for use by the power management interface */
+#define MBOX_CHAN_FB 1 /* for use by the frame buffer */
+#define MBOX_CHAN_VCHIQ 3 /* for use by the VCHIQ interface */
+#define MBOX_CHAN_PROPERTY 8 /* for use by the property channel */
+#define MBOX_CHAN_COUNT 9
+
+#define MBOX_SIZE 32
+#define MBOX_INVALID_DATA 0x0f
+
+/* Layout of the private address space used for communication between
+ * the mbox device emulation, and child devices: each channel occupies
+ * 16 bytes of address space, but only two registers are presently defined.
+ */
+#define MBOX_AS_CHAN_SHIFT 4
+#define MBOX_AS_DATA 0 /* request / response data (RW at offset 0) */
+#define MBOX_AS_PENDING 4 /* pending response status (RO at offset 4) */
+
+#endif /* BCM2835_MBOX_DEFS_H */
--
2.5.3
