pseries: Consolidate construction of /chosen device tree node

For historical reasons, building the /chosen node in the guest device tree
is split across several places and includes both parts which write the DT
sequentially and others which use random access functions.

This patch consolidates construction of the node into one place, using
random access functions throughout.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>

hw/ppc/spapr.c

@@ -273,14 +273,10 @@ static void add_str(GString *s, const gchar *s1)
 
 static void *spapr_create_fdt_skel(sPAPRMachineState *spapr)
 {
-    MachineState *machine = MACHINE(spapr);
     void *fdt;
-    uint32_t start_prop = cpu_to_be32(spapr->initrd_base);
-    uint32_t end_prop = cpu_to_be32(spapr->initrd_base + spapr->initrd_size);
     GString *hypertas = g_string_sized_new(256);
     GString *qemu_hypertas = g_string_sized_new(256);
     uint32_t refpoints[] = {cpu_to_be32(0x4), cpu_to_be32(0x4)};
-    unsigned char vec5[] = {0x0, 0x0, 0x0, 0x0, 0x0, 0x80};
     char *buf;
 
     add_str(hypertas, "hcall-pft");
@@ -337,35 +333,6 @@ static void *spapr_create_fdt_skel(sPAPRMachineState *spapr)
     _FDT((fdt_property_cell(fdt, "#address-cells", 0x2)));
     _FDT((fdt_property_cell(fdt, "#size-cells", 0x2)));
 
-    /* /chosen */
-    _FDT((fdt_begin_node(fdt, "chosen")));
-
-    /* Set Form1_affinity */
-    _FDT((fdt_property(fdt, "ibm,architecture-vec-5", vec5, sizeof(vec5))));
-
-    _FDT((fdt_property_string(fdt, "bootargs", machine->kernel_cmdline)));
-    _FDT((fdt_property(fdt, "linux,initrd-start",
-                       &start_prop, sizeof(start_prop))));
-    _FDT((fdt_property(fdt, "linux,initrd-end",
-                       &end_prop, sizeof(end_prop))));
-    if (spapr->kernel_size) {
-        uint64_t kprop[2] = { cpu_to_be64(KERNEL_LOAD_ADDR),
-                              cpu_to_be64(spapr->kernel_size) };
-
-        _FDT((fdt_property(fdt, "qemu,boot-kernel", &kprop, sizeof(kprop))));
-        if (spapr->kernel_le) {
-            _FDT((fdt_property(fdt, "qemu,boot-kernel-le", NULL, 0)));
-        }
-    }
-    if (boot_menu) {
-        _FDT((fdt_property_cell(fdt, "qemu,boot-menu", boot_menu)));
-    }
-    _FDT((fdt_property_cell(fdt, "qemu,graphic-width", graphic_width)));
-    _FDT((fdt_property_cell(fdt, "qemu,graphic-height", graphic_height)));
-    _FDT((fdt_property_cell(fdt, "qemu,graphic-depth", graphic_depth)));
-
-    _FDT((fdt_end_node(fdt)));
-
     /* RTAS */
     _FDT((fdt_begin_node(fdt, "rtas")));
 
@@ -873,6 +840,68 @@ int spapr_h_cas_compose_response(sPAPRMachineState *spapr,
     return 0;
 }
 
+static void spapr_dt_chosen(sPAPRMachineState *spapr, void *fdt)
+{
+    MachineState *machine = MACHINE(spapr);
+    int chosen;
+    const char *boot_device = machine->boot_order;
+    char *stdout_path = spapr_vio_stdout_path(spapr->vio_bus);
+    size_t cb = 0;
+    char *bootlist = get_boot_devices_list(&cb, true);
+    unsigned char vec5[] = {0x0, 0x0, 0x0, 0x0, 0x0, 0x80};
+
+    _FDT(chosen = fdt_add_subnode(fdt, 0, "chosen"));
+
+    /* Set Form1_affinity */
+    _FDT(fdt_setprop(fdt, chosen, "ibm,architecture-vec-5",
+                     vec5, sizeof(vec5)));
+
+    _FDT(fdt_setprop_string(fdt, chosen, "bootargs", machine->kernel_cmdline));
+    _FDT(fdt_setprop_cell(fdt, chosen, "linux,initrd-start",
+                          spapr->initrd_base));
+    _FDT(fdt_setprop_cell(fdt, chosen, "linux,initrd-end",
+                          spapr->initrd_base + spapr->initrd_size));
+
+    if (spapr->kernel_size) {
+        uint64_t kprop[2] = { cpu_to_be64(KERNEL_LOAD_ADDR),
+                              cpu_to_be64(spapr->kernel_size) };
+
+        _FDT(fdt_setprop(fdt, chosen, "qemu,boot-kernel",
+                         &kprop, sizeof(kprop)));
+        if (spapr->kernel_le) {
+            _FDT(fdt_setprop(fdt, chosen, "qemu,boot-kernel-le", NULL, 0));
+        }
+    }
+    if (boot_menu) {
+        _FDT((fdt_setprop_cell(fdt, chosen, "qemu,boot-menu", boot_menu)));
+    }
+    _FDT(fdt_setprop_cell(fdt, chosen, "qemu,graphic-width", graphic_width));
+    _FDT(fdt_setprop_cell(fdt, chosen, "qemu,graphic-height", graphic_height));
+    _FDT(fdt_setprop_cell(fdt, chosen, "qemu,graphic-depth", graphic_depth));
+
+    if (cb && bootlist) {
+        int i;
+
+        for (i = 0; i < cb; i++) {
+            if (bootlist[i] == '\n') {
+                bootlist[i] = ' ';
+            }
+        }
+        _FDT(fdt_setprop_string(fdt, chosen, "qemu,boot-list", bootlist));
+    }
+
+    if (boot_device && strlen(boot_device)) {
+        _FDT(fdt_setprop_string(fdt, chosen, "qemu,boot-device", boot_device));
+    }
+
+    if (!spapr->has_graphics && stdout_path) {
+        _FDT(fdt_setprop_string(fdt, chosen, "linux,stdout-path", stdout_path));
+    }
+
+    g_free(stdout_path);
+    g_free(bootlist);
+}
+
 static void *spapr_build_fdt(sPAPRMachineState *spapr,
                              hwaddr rtas_addr,
                              hwaddr rtas_size)
@@ -880,10 +909,7 @@ static void *spapr_build_fdt(sPAPRMachineState *spapr,
     MachineState *machine = MACHINE(qdev_get_machine());
     MachineClass *mc = MACHINE_GET_CLASS(machine);
     sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(machine);
-    const char *boot_device = machine->boot_order;
+    int ret;
-    int ret, i;
-    size_t cb = 0;
-    char *bootlist;
     void *fdt;
     sPAPRPHBState *phb;
 
@@ -932,34 +958,6 @@ static void *spapr_build_fdt(sPAPRMachineState *spapr,
     /* cpus */
     spapr_populate_cpus_dt_node(fdt, spapr);
 
-    bootlist = get_boot_devices_list(&cb, true);
-    if (cb && bootlist) {
-        int offset = fdt_path_offset(fdt, "/chosen");
-        if (offset < 0) {
-            exit(1);
-        }
-        for (i = 0; i < cb; i++) {
-            if (bootlist[i] == '\n') {
-                bootlist[i] = ' ';
-            }
-
-        }
-        ret = fdt_setprop_string(fdt, offset, "qemu,boot-list", bootlist);
-    }
-
-    if (boot_device && strlen(boot_device)) {
-        int offset = fdt_path_offset(fdt, "/chosen");
-
-        if (offset < 0) {
-            exit(1);
-        }
-        fdt_setprop_string(fdt, offset, "qemu,boot-device", boot_device);
-    }
-
-    if (!spapr->has_graphics) {
-        spapr_populate_chosen_stdout(fdt, spapr->vio_bus);
-    }
-
     if (smc->dr_lmb_enabled) {
         _FDT(spapr_drc_populate_dt(fdt, 0, NULL, SPAPR_DR_CONNECTOR_TYPE_LMB));
     }
@@ -974,7 +972,8 @@ static void *spapr_build_fdt(sPAPRMachineState *spapr,
         }
     }
 
-    g_free(bootlist);
+    /* /chosen */
+    spapr_dt_chosen(spapr, fdt);
 
     /* Build memory reserve map */
     if (spapr->kernel_size) {

hw/ppc/spapr_vio.c

@@ -665,28 +665,19 @@ out:
     return ret;
 }
 
-int spapr_populate_chosen_stdout(void *fdt, VIOsPAPRBus *bus)
+gchar *spapr_vio_stdout_path(VIOsPAPRBus *bus)
 {
     VIOsPAPRDevice *dev;
     char *name, *path;
-    int ret, offset;
 
     dev = spapr_vty_get_default(bus);
-    if (!dev)
+    if (!dev) {
-        return 0;
+        return NULL;
-
-    offset = fdt_path_offset(fdt, "/chosen");
-    if (offset < 0) {
-        return offset;
     }
 
     name = spapr_vio_get_dev_name(DEVICE(dev));
     path = g_strdup_printf("/vdevice/%s", name);
 
-    ret = fdt_setprop_string(fdt, offset, "linux,stdout-path", path);
-
     g_free(name);
-    g_free(path);
+    return path;
-
-    return ret;
 }

include/hw/ppc/spapr_vio.h

@@ -81,7 +81,7 @@ struct VIOsPAPRBus {
 extern VIOsPAPRBus *spapr_vio_bus_init(void);
 extern VIOsPAPRDevice *spapr_vio_find_by_reg(VIOsPAPRBus *bus, uint32_t reg);
 extern int spapr_populate_vdevice(VIOsPAPRBus *bus, void *fdt);
-extern int spapr_populate_chosen_stdout(void *fdt, VIOsPAPRBus *bus);
+extern gchar *spapr_vio_stdout_path(VIOsPAPRBus *bus);
 
 static inline qemu_irq spapr_vio_qirq(VIOsPAPRDevice *dev)
 {