bcm2835_fb: add framebuffer device for Raspberry Pi

The framebuffer occupies the upper portion of memory (64MiB by
default), but it can only be controlled/configured via a system
mailbox or property channel (to be added by a subsequent patch).

Signed-off-by: Grégory ESTRADE <gregory.estrade@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
Message-id: 1457467526-8840-4-git-send-email-Andrew.Baumann@microsoft.com
[AB: added Windows (BGR) support and cleanup/refactoring for upstream submission]
Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 43 insertions, 2 deletions

diff --git a/hw/arm/bcm2835_peripherals.c b/hw/arm/bcm2835_peripherals.c
index d6453cc5ab..c2fe6b7625 100644
--- a/hw/arm/bcm2835_peripherals.c
+++ b/hw/arm/bcm2835_peripherals.c
@@ -62,6 +62,16 @@ static void bcm2835_peripherals_init(Object *obj)
     object_property_add_const_link(OBJECT(&s->mboxes), "mbox-mr",
                                    OBJECT(&s->mbox_mr), &error_abort);
 
+    /* Framebuffer */
+    object_initialize(&s->fb, sizeof(s->fb), TYPE_BCM2835_FB);
+    object_property_add_child(obj, "fb", OBJECT(&s->fb), NULL);
+    object_property_add_alias(obj, "vcram-size", OBJECT(&s->fb), "vcram-size",
+                              &error_abort);
+    qdev_set_parent_bus(DEVICE(&s->fb), sysbus_get_default());
+
+    object_property_add_const_link(OBJECT(&s->fb), "dma-mr",
+                                   OBJECT(&s->gpu_bus_mr), &error_abort);
+
     /* Property channel */
     object_initialize(&s->property, sizeof(s->property), TYPE_BCM2835_PROPERTY);
     object_property_add_child(obj, "property", OBJECT(&s->property), NULL);
@@ -84,7 +94,7 @@ static void bcm2835_peripherals_realize(DeviceState *dev, Error **errp)
     Object *obj;
     MemoryRegion *ram;
     Error *err = NULL;
-    uint32_t ram_size;
+    uint32_t ram_size, vcram_size;
     CharDriverState *chr;
     int n;
 
@@ -174,6 +184,32 @@ static void bcm2835_peripherals_realize(DeviceState *dev, Error **errp)
         qdev_get_gpio_in_named(DEVICE(&s->ic), BCM2835_IC_ARM_IRQ,
                                INTERRUPT_ARM_MAILBOX));
 
+    /* Framebuffer */
+    vcram_size = (uint32_t)object_property_get_int(OBJECT(s), "vcram-size",
+                                                   &err);
+    if (err) {
+        error_propagate(errp, err);
+        return;
+    }
+
+    object_property_set_int(OBJECT(&s->fb), ram_size - vcram_size,
+                            "vcram-base", &err);
+    if (err) {
+        error_propagate(errp, err);
+        return;
+    }
+
+    object_property_set_bool(OBJECT(&s->fb), true, "realized", &err);
+    if (err) {
+        error_propagate(errp, err);
+        return;
+    }
+
+    memory_region_add_subregion(&s->mbox_mr, MBOX_CHAN_FB << MBOX_AS_CHAN_SHIFT,
+                sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->fb), 0));
+    sysbus_connect_irq(SYS_BUS_DEVICE(&s->fb), 0,
+                       qdev_get_gpio_in(DEVICE(&s->mboxes), MBOX_CHAN_FB));
+
     /* Property channel */
     object_property_set_int(OBJECT(&s->property), ram_size, "ram-size", &err);
     if (err) {
diff --git a/hw/arm/bcm2836.c b/hw/arm/bcm2836.c
index 032143905e..89a6b35b81 100644
--- a/hw/arm/bcm2836.c
+++ b/hw/arm/bcm2836.c
@@ -42,6 +42,8 @@ static void bcm2836_init(Object *obj)
                               &error_abort);
     object_property_add_alias(obj, "board-rev", OBJECT(&s->peripherals),
                               "board-rev", &error_abort);
+    object_property_add_alias(obj, "vcram-size", OBJECT(&s->peripherals),
+                              "vcram-size", &error_abort);
     qdev_set_parent_bus(DEVICE(&s->peripherals), sysbus_get_default());
 }
 
diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c
index 65822792fe..54982095b2 100644
--- a/hw/arm/raspi.c
+++ b/hw/arm/raspi.c
@@ -113,6 +113,7 @@ static void setup_boot(MachineState *machine, int version, size_t ram_size)
 static void raspi2_init(MachineState *machine)
 {
     RasPiState *s = g_new0(RasPiState, 1);
+    uint32_t vcram_size;
     DriveInfo *di;
     BlockBackend *blk;
     BusState *bus;
@@ -149,7 +150,9 @@ static void raspi2_init(MachineState *machine)
     qdev_prop_set_drive(carddev, "drive", blk, &error_fatal);
     object_property_set_bool(OBJECT(carddev), true, "realized", &error_fatal);
 
-    setup_boot(machine, 2, machine->ram_size);
+    vcram_size = object_property_get_int(OBJECT(&s->soc), "vcram-size",
+                                         &error_abort);
+    setup_boot(machine, 2, machine->ram_size - vcram_size);
 }
 
 static void raspi2_machine_init(MachineClass *mc)