[PATCH V3 02/10] xen/arm: introduce new helper device_tree_get_meminfo

[Penny Zheng <penny.zheng@xxxxxxx>]

A few functions iterate over the device tree property to get memory info,
like "reg" or "xen,static-mem", so this commit creates a new helper
device_tree_get_meminfo to extract the
common codes.

Signed-off-by: Penny Zheng <penny.zheng@xxxxxxx>
---
 xen/arch/arm/bootfdt.c | 104 +++++++++++++++++------------------------
 1 file changed, 42 insertions(+), 62 deletions(-)

diff --git a/xen/arch/arm/bootfdt.c b/xen/arch/arm/bootfdt.c
index d2714446e1..04210684c9 100644
--- a/xen/arch/arm/bootfdt.c
+++ b/xen/arch/arm/bootfdt.c
@@ -63,6 +63,44 @@ void __init device_tree_get_reg(const __be32 **cell, u32 
address_cells,
     *size = dt_next_cell(size_cells, cell);
 }
 
+static int __init device_tree_get_meminfo(const void *fdt, int node,
+                                          const char *prop_name,
+                                          u32 address_cells, u32 size_cells,
+                                          void *data)
+{
+    const struct fdt_property *prop;
+    unsigned int i, banks;
+    const __be32 *cell;
+    u32 reg_cells = address_cells + size_cells;
+    paddr_t start, size;
+    struct meminfo *mem = data;
+
+    prop = fdt_get_property(fdt, node, prop_name, NULL);
+    if ( !prop )
+        return -ENOENT;
+
+    cell = (const __be32 *)prop->data;
+    banks = fdt32_to_cpu(prop->len) / (reg_cells * sizeof (u32));
+
+    for ( i = 0; i < banks && mem->nr_banks < NR_MEM_BANKS; i++ )
+    {
+        device_tree_get_reg(&cell, address_cells, size_cells, &start, &size);
+        /* Some DT may describe empty bank, ignore them */
+        if ( !size )
+            continue;
+        mem->bank[mem->nr_banks].start = start;
+        mem->bank[mem->nr_banks].size = size;
+        mem->nr_banks++;
+    }
+
+    if ( i < banks )
+    {
+        printk("Warning: Max number of supported memory regions reached.\n");
+        return -ENOSPC;
+    }
+    return 0;
+}
+
 u32 __init device_tree_get_u32(const void *fdt, int node,
                                const char *prop_name, u32 dflt)
 {
@@ -139,14 +177,6 @@ static int __init process_memory_node(const void *fdt, int 
node,
                                       u32 address_cells, u32 size_cells,
                                       void *data)
 {
-    const struct fdt_property *prop;
-    int i;
-    int banks;
-    const __be32 *cell;
-    paddr_t start, size;
-    u32 reg_cells = address_cells + size_cells;
-    struct meminfo *mem = data;
-
     if ( address_cells < 1 || size_cells < 1 )
     {
         printk("fdt: node `%s': invalid #address-cells or #size-cells",
@@ -154,27 +184,7 @@ static int __init process_memory_node(const void *fdt, int 
node,
         return -EINVAL;
     }
 
-    prop = fdt_get_property(fdt, node, "reg", NULL);
-    if ( !prop )
-        return -ENOENT;
-
-    cell = (const __be32 *)prop->data;
-    banks = fdt32_to_cpu(prop->len) / (reg_cells * sizeof (u32));
-
-    for ( i = 0; i < banks && mem->nr_banks < NR_MEM_BANKS; i++ )
-    {
-        device_tree_get_reg(&cell, address_cells, size_cells, &start, &size);
-        /* Some DT may describe empty bank, ignore them */
-        if ( !size )
-            continue;
-        mem->bank[mem->nr_banks].start = start;
-        mem->bank[mem->nr_banks].size = size;
-        mem->nr_banks++;
-    }
-
-    if ( i < banks )
-        return -ENOSPC;
-    return 0;
+    return device_tree_get_meminfo(fdt, node, "reg", address_cells, 
size_cells, data);
 }
 
 static int __init process_reserved_memory_node(const void *fdt, int node,
@@ -195,13 +205,7 @@ static int __init process_reserved_memory_node(const void 
*fdt, int node,
 
 static int __init process_static_memory(const void *fdt, int node, void *data)
 {
-    int i = 0, banks;
-    const __be32 *cell;
-    paddr_t start, size;
-    u32 address_cells, size_cells, reg_cells;
-    struct meminfo *mem = data;
-    const struct fdt_property *prop;
-
+    u32 address_cells, size_cells;
 
     address_cells = device_tree_get_u32(fdt, node,
                                         "#xen,static-mem-address-cells", 0);
@@ -213,33 +217,9 @@ static int __init process_static_memory(const void *fdt, 
int node, void *data)
                  "\"#xen,static-mem-address-cell\".\n");
          return -EINVAL;
     }
-    reg_cells = address_cells + size_cells;
-
-    prop = fdt_get_property(fdt, node, "xen,static-mem", NULL);
-    /*
-     * Static memory shall belong to a specific domain, that is,
-     * its node `domUx` has compatible string "xen,domain".
-     */
-    if ( fdt_node_check_compatible(fdt, node, "xen,domain") != 0 )
-    {
-        printk("xen,static-mem property can only be located under /domUx 
node.\n");
-        return -EINVAL;
-    }
-
-    cell = (const __be32 *)prop->data;
-    banks = fdt32_to_cpu(prop->len) / (reg_cells * sizeof (u32));
-
-    for ( ; i < banks && mem->nr_banks < NR_MEM_BANKS; i++ )
-    {
-        device_tree_get_reg(&cell, address_cells, size_cells, &start, &size);
-        mem->bank[mem->nr_banks].start = start;
-        mem->bank[mem->nr_banks].size = size;
-        mem->nr_banks++;
-    }
 
-    if ( i < banks )
-        return -ENOSPC;
-    return 0;
+    return device_tree_get_meminfo(fdt, node, "xen,static-mem", address_cells,
+                                   size_cells, data);
 }
 
 static int __init process_reserved_memory(const void *fdt, int node,
-- 
2.25.1