[Qemu-devel] [RFC v4 12/13] hw/vfio/platform: add default dt generation for vfio device

[Eric Auger]

implement a default dt generation for VFIO platform device. This
enables dynamic instantiation. If the device tree generation does
not match the expectation it is possible to derive a component
and write one's own fdt_add_device_node method.

Signed-off-by: Alvise Rigo <address@hidden>
Signed-off-by: Eric Auger <address@hidden>
---
 hw/vfio/platform.c              | 143 ++++++++++++++++++++++++++++++++++++++++
 include/hw/vfio/vfio-platform.h |   1 +
 2 files changed, 144 insertions(+)

diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
index fb0f7c9..447ce50 100644
--- a/hw/vfio/platform.c
+++ b/hw/vfio/platform.c
@@ -22,6 +22,7 @@
 #include "qemu/range.h"
 #include "sysemu/sysemu.h"
 #include "hw/vfio/vfio-platform.h"
+#include "hw/misc/platform_devices.h"
 
 extern const MemoryRegionOps vfio_region_ops;
 extern const MemoryListener vfio_memory_listener;
@@ -573,6 +574,142 @@ static void vfio_platform_realize(DeviceState *dev, Error 
**errp)
     }
 }
 
+static char *format_compat(char * compat)
+{
+    char *str_ptr, *corrected_compat;
+    /*
+     * process compatibility property string passed by end-user
+     * replaces / by , and ; by NUL character
+     */
+    corrected_compat = g_strdup(compat);
+    /*
+     * the total length of the string has to include also the last
+     * NUL char.
+     */
+
+    str_ptr = corrected_compat;
+    while ((str_ptr = strchr(str_ptr, '/')) != NULL) {
+        *str_ptr = ',';
+    }
+
+    /* substitute ";" with the NUL char */
+    str_ptr = corrected_compat;
+    while ((str_ptr = strchr(str_ptr, ';')) != NULL) {
+        *str_ptr = '\0';
+    }
+
+    return corrected_compat;
+}
+
+static void wrap_fdt_add_node(SysBusDevice *sbdev, void *opaque)
+{
+    PlatformDevtreeData *data = opaque;
+    VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
+    VFIOPlatformDeviceClass *vdevc = VFIO_PLATFORM_DEVICE_GET_CLASS(sbdev);
+    VFIODevice *vbasedev = &vdev->vbasedev;
+    gchar irq_number_prop[8];
+    Object *obj = OBJECT(sbdev);
+    char *corrected_compat;
+    uint64_t irq_number;
+    int compat_str_len = strlen(vdev->compat)+1;
+    int i;
+
+    corrected_compat = format_compat(vdev->compat);
+    snprintf(vdev->compat, compat_str_len, "%s", corrected_compat);
+    g_free(corrected_compat);
+
+    vdevc->fdt_add_device_node(sbdev, opaque);
+
+    for (i = 0; i < vbasedev->num_irqs; i++) {
+        snprintf(irq_number_prop, sizeof(irq_number_prop), "irq[%d]", i);
+        irq_number = object_property_get_int(obj, irq_number_prop, NULL)
+                                                 + data->irq_start;
+        /*
+         * this is a hack: this does not relate to dt creation
+         * for setting up irqfd we must give the virtual IRQ number
+         * which is the sum of irq_start and actual platform bus irq
+         * index. at realize point we do not have this info.
+         * in case of static instantiation, the irq connect is not yet
+         * done. In case of dynamic instantiation it was done but we
+         * miss irq_start which is not stored in the sysbus device.
+         */
+        if (vdev->irqfd_allowed) {
+            vfio_setup_irqfd(sbdev, i, irq_number);
+        }
+    }
+}
+
+static void default_fdt_add_device_node(SysBusDevice *sbdev, void *opaque)
+{
+    PlatformDevtreeData *data = opaque;
+    void *fdt = data->fdt;
+    const char *parent_node = data->node;
+    uint64_t platform_bus_base = data->platform_bus_base;
+    int compat_str_len;
+    char *nodename;
+    int i, ret;
+    uint32_t *irq_attr;
+    uint64_t *reg_attr;
+    uint64_t mmio_base;
+    uint64_t irq_number;
+    gchar mmio_base_prop[8];
+    gchar irq_number_prop[8];
+    VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
+    VFIODevice *vbasedev = &vdev->vbasedev;
+    Object *obj = OBJECT(sbdev);
+
+    mmio_base = object_property_get_int(obj, "mmio[0]", NULL);
+
+    nodename = g_strdup_printf("%s/address@hidden" PRIx64, parent_node,
+                               vbasedev->name,
+                               mmio_base + platform_bus_base);
+
+    qemu_fdt_add_subnode(fdt, nodename);
+
+    compat_str_len = strlen(vdev->compat) + 1;
+    qemu_fdt_setprop(fdt, nodename, "compatible",
+                            vdev->compat, compat_str_len);
+
+    reg_attr = g_new(uint64_t, vbasedev->num_regions*4);
+
+    for (i = 0; i < vbasedev->num_regions; i++) {
+        snprintf(mmio_base_prop, sizeof(mmio_base_prop), "mmio[%d]", i);
+        mmio_base = object_property_get_int(obj, mmio_base_prop, NULL);
+        reg_attr[4*i] = 2;
+        reg_attr[4*i+1] = mmio_base + platform_bus_base;
+        reg_attr[4*i+2] = 2;
+        reg_attr[4*i+3] = memory_region_size(&vdev->regions[i]->mem);
+    }
+
+    ret = qemu_fdt_setprop_sized_cells_from_array(fdt, nodename, "reg",
+                     vbasedev->num_regions*2, reg_attr);
+    if (ret < 0) {
+        error_report("could not set reg property of node %s", nodename);
+    }
+
+    irq_attr = g_new(uint32_t, vbasedev->num_irqs*3);
+
+    for (i = 0; i < vbasedev->num_irqs; i++) {
+        snprintf(irq_number_prop, sizeof(irq_number_prop), "irq[%d]", i);
+        irq_number = object_property_get_int(obj, irq_number_prop, NULL)
+                                                 + data->irq_start;
+        irq_attr[3*i] = cpu_to_be32(0);
+        irq_attr[3*i+1] = cpu_to_be32(irq_number);
+        irq_attr[3*i+2] = cpu_to_be32(0x4);
+    }
+
+   ret = qemu_fdt_setprop(fdt, nodename, "interrupts",
+                     irq_attr, vbasedev->num_irqs*3*sizeof(uint32_t));
+    if (ret < 0) {
+        error_report("could not set interrupts property of node %s",
+                     nodename);
+    }
+
+    g_free(nodename);
+    g_free(irq_attr);
+    g_free(reg_attr);
+}
+
 static const VMStateDescription vfio_platform_vmstate = {
     .name = TYPE_VFIO_PLATFORM,
     .version_id = 3,
@@ -599,6 +736,12 @@ static Property vfio_platform_dev_properties[] = {
 static void vfio_platform_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    SysBusDeviceClass *sbdevc = SYS_BUS_DEVICE_CLASS(klass);
+    VFIOPlatformDeviceClass *vdc = VFIO_PLATFORM_DEVICE_CLASS(klass);
+
+    /* substitute wrap_fdt_add_node to parent fdt_add_node */
+    sbdevc->fdt_add_node = wrap_fdt_add_node;
+    vdc->fdt_add_device_node = default_fdt_add_device_node;
 
     dc->realize = vfio_platform_realize;
     dc->props = vfio_platform_dev_properties;
diff --git a/include/hw/vfio/vfio-platform.h b/include/hw/vfio/vfio-platform.h
index 134fc1e..1e9a5f4 100644
--- a/include/hw/vfio/vfio-platform.h
+++ b/include/hw/vfio/vfio-platform.h
@@ -59,6 +59,7 @@ typedef struct VFIOPlatformDeviceClass {
     /*< private >*/
     SysBusDeviceClass parent_class;
     /*< public >*/
+    void (*fdt_add_device_node)(SysBusDevice *sbdev, void *opaque);
 } VFIOPlatformDeviceClass;
 
 #define VFIO_PLATFORM_DEVICE(obj) \
-- 
1.8.3.2