[PATCH 34/37] xen/arm: enable device tree based NUMA in system init

[Wei Chen <wei.chen@xxxxxxx>]

In this patch, we can start to create NUMA system that is
based on device tree.

Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
---
 xen/arch/arm/numa.c        | 55 ++++++++++++++++++++++++++++++++++++++
 xen/arch/arm/setup.c       |  7 +++++
 xen/include/asm-arm/numa.h |  6 +++++
 3 files changed, 68 insertions(+)

diff --git a/xen/arch/arm/numa.c b/xen/arch/arm/numa.c
index 7f05299b76..d7a3d32d4b 100644
--- a/xen/arch/arm/numa.c
+++ b/xen/arch/arm/numa.c
@@ -18,8 +18,10 @@
  *
  */
 #include <xen/init.h>
+#include <xen/device_tree.h>
 #include <xen/nodemask.h>
 #include <xen/numa.h>
+#include <xen/pfn.h>
 
 static uint8_t __read_mostly
 node_distance_map[MAX_NUMNODES][MAX_NUMNODES] = {
@@ -85,6 +87,59 @@ uint8_t __node_distance(nodeid_t from, nodeid_t to)
 }
 EXPORT_SYMBOL(__node_distance);
 
+void __init numa_init(bool acpi_off)
+{
+    uint32_t idx;
+    paddr_t ram_start = ~0;
+    paddr_t ram_size = 0;
+    paddr_t ram_end = 0;
+
+    /* NUMA has been turned off through Xen parameters */
+    if ( numa_off )
+        goto mem_init;
+
+    /* Initialize NUMA from device tree when system is not ACPI booted */
+    if ( acpi_off )
+    {
+        int ret = numa_device_tree_init(device_tree_flattened);
+        if ( ret )
+        {
+            printk(XENLOG_WARNING
+                   "Init NUMA from device tree failed, ret=%d\n", ret);
+            numa_off = true;
+        }
+    }
+    else
+    {
+        /* We don't support NUMA for ACPI boot currently */
+        printk(XENLOG_WARNING
+               "ACPI NUMA has not been supported yet, NUMA off!\n");
+        numa_off = true;
+    }
+
+mem_init:
+    /*
+     * Find the minimal and maximum address of RAM, NUMA will
+     * build a memory to node mapping table for the whole range.
+     */
+    ram_start = bootinfo.mem.bank[0].start;
+    ram_size  = bootinfo.mem.bank[0].size;
+    ram_end   = ram_start + ram_size;
+    for ( idx = 1 ; idx < bootinfo.mem.nr_banks; idx++ )
+    {
+        paddr_t bank_start = bootinfo.mem.bank[idx].start;
+        paddr_t bank_size = bootinfo.mem.bank[idx].size;
+        paddr_t bank_end = bank_start + bank_size;
+
+        ram_size  = ram_size + bank_size;
+        ram_start = min(ram_start, bank_start);
+        ram_end   = max(ram_end, bank_end);
+    }
+
+    numa_initmem_init(PFN_UP(ram_start), PFN_DOWN(ram_end));
+    return;
+}
+
 uint32_t __init arch_meminfo_get_nr_bank(void)
 {
        return bootinfo.mem.nr_banks;
diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 1f0fbc95b5..6097850682 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -905,6 +905,13 @@ void __init start_xen(unsigned long boot_phys_offset,
     /* Parse the ACPI tables for possible boot-time configuration */
     acpi_boot_table_init();
 
+    /*
+     * Try to initialize NUMA system, if failed, the system will
+     * fallback to uniform system which means system has only 1
+     * NUMA node.
+     */
+    numa_init(acpi_disabled);
+
     end_boot_allocator();
 
     /*
diff --git a/xen/include/asm-arm/numa.h b/xen/include/asm-arm/numa.h
index f46e8e2935..5b03dde87f 100644
--- a/xen/include/asm-arm/numa.h
+++ b/xen/include/asm-arm/numa.h
@@ -24,6 +24,7 @@ typedef u8 nodeid_t;
 
 extern void numa_set_distance(nodeid_t from, nodeid_t to, uint32_t distance);
 extern int numa_device_tree_init(const void *fdt);
+extern void numa_init(bool acpi_off);
 
 #else
 
@@ -47,6 +48,11 @@ extern mfn_t first_valid_mfn;
 #define node_start_pfn(nid) (mfn_x(first_valid_mfn))
 #define __node_distance(a, b) (20)
 
+static inline void numa_init(bool acpi_off)
+{
+
+}
+
 static inline void numa_add_cpu(int cpu)
 {
 
-- 
2.25.1