make_memory_node() does not rely on any Arm-specific functionality and is
fully reused by RISC-V, making it a good candidate to move into common code.

Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
---
Changes in v2:
 - New patch
---
 xen/arch/arm/domain_build.c           | 74 --------------------------
 xen/common/device-tree/domain-build.c | 75 +++++++++++++++++++++++++++
 2 files changed, 75 insertions(+), 74 deletions(-)

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 6d1c9583b1..986a456f17 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -646,80 +646,6 @@ static int __init fdt_property_interrupts(const struct kernel_info *kinfo,
     return res;
 }
 
-int __init make_memory_node(const struct kernel_info *kinfo, int addrcells,
-                            int sizecells, const struct membanks *mem)
-{
-    void *fdt = kinfo->fdt;
-    unsigned int i;
-    int res, reg_size = addrcells + sizecells;
-    int nr_cells = 0;
-    __be32 reg[DT_MEM_NODE_REG_RANGE_SIZE];
-    __be32 *cells;
-
-    if ( mem->nr_banks == 0 )
-        return -ENOENT;
-
-    /* find the first memory range that is reserved for device (or firmware) */
-    for ( i = 0; i < mem->nr_banks &&
-                 (mem->bank[i].type != MEMBANK_DEFAULT); i++ )
-        ;
-
-    if ( i == mem->nr_banks )
-        return 0;
-
-    dt_dprintk("Create memory node\n");
-
-    res = domain_fdt_begin_node(fdt, "memory", mem->bank[i].start);
-    if ( res )
-        return res;
-
-    res = fdt_property_string(fdt, "device_type", "memory");
-    if ( res )
-        return res;
-
-    cells = &reg[0];
-    for ( ; i < mem->nr_banks; i++ )
-    {
-        u64 start = mem->bank[i].start;
-        u64 size = mem->bank[i].size;
-
-        if ( (mem->bank[i].type == MEMBANK_STATIC_DOMAIN) ||
-             (mem->bank[i].type == MEMBANK_FDT_RESVMEM) )
-            continue;
-
-        nr_cells += reg_size;
-        BUG_ON(nr_cells >= ARRAY_SIZE(reg));
-        dt_child_set_range(&cells, addrcells, sizecells, start, size);
-    }
-
-    /*
-     * static shared memory banks need to be listed as /memory node, so when
-     * this function is handling the normal memory, add the banks.
-     */
-    if ( mem == kernel_info_get_mem_const(kinfo) )
-        shm_mem_node_fill_reg_range(kinfo, reg, &nr_cells, addrcells,
-                                    sizecells);
-
-    for ( cells = reg, i = 0; cells < reg + nr_cells; i++, cells += reg_size )
-    {
-        uint64_t start = dt_read_number(cells, addrcells);
-        uint64_t size = dt_read_number(cells + addrcells, sizecells);
-
-        dt_dprintk("  Bank %u: %#"PRIx64"->%#"PRIx64"\n",
-                   i, start, start + size);
-    }
-
-    dt_dprintk("(reg size %d, nr cells %d)\n", reg_size, nr_cells);
-
-    res = fdt_property(fdt, "reg", reg, nr_cells * sizeof(*reg));
-    if ( res )
-        return res;
-
-    res = fdt_end_node(fdt);
-
-    return res;
-}
-
 int __init add_ext_regions(unsigned long s_gfn, unsigned long e_gfn,
                            void *data)
 {
diff --git a/xen/common/device-tree/domain-build.c b/xen/common/device-tree/domain-build.c
index 774790aab3..6708c9dd66 100644
--- a/xen/common/device-tree/domain-build.c
+++ b/xen/common/device-tree/domain-build.c
@@ -8,6 +8,7 @@
 #include <xen/mm.h>
 #include <xen/sched.h>
 #include <xen/sizes.h>
+#include <xen/static-shmem.h>
 #include <xen/types.h>
 #include <xen/vmap.h>
 
@@ -451,6 +452,80 @@ int __init make_chosen_node(const struct kernel_info *kinfo)
     return res;
 }
 
+int __init make_memory_node(const struct kernel_info *kinfo, int addrcells,
+                            int sizecells, const struct membanks *mem)
+{
+    void *fdt = kinfo->fdt;
+    unsigned int i;
+    int res, reg_size = addrcells + sizecells;
+    int nr_cells = 0;
+    __be32 reg[DT_MEM_NODE_REG_RANGE_SIZE];
+    __be32 *cells;
+
+    if ( mem->nr_banks == 0 )
+        return -ENOENT;
+
+    /* find the first memory range that is reserved for device (or firmware) */
+    for ( i = 0; i < mem->nr_banks &&
+                 (mem->bank[i].type != MEMBANK_DEFAULT); i++ )
+        ;
+
+    if ( i == mem->nr_banks )
+        return 0;
+
+    dt_dprintk("Create memory node\n");
+
+    res = domain_fdt_begin_node(fdt, "memory", mem->bank[i].start);
+    if ( res )
+        return res;
+
+    res = fdt_property_string(fdt, "device_type", "memory");
+    if ( res )
+        return res;
+
+    cells = &reg[0];
+    for ( ; i < mem->nr_banks; i++ )
+    {
+        u64 start = mem->bank[i].start;
+        u64 size = mem->bank[i].size;
+
+        if ( (mem->bank[i].type == MEMBANK_STATIC_DOMAIN) ||
+             (mem->bank[i].type == MEMBANK_FDT_RESVMEM) )
+            continue;
+
+        nr_cells += reg_size;
+        BUG_ON(nr_cells >= ARRAY_SIZE(reg));
+        dt_child_set_range(&cells, addrcells, sizecells, start, size);
+    }
+
+    /*
+     * static shared memory banks need to be listed as /memory node, so when
+     * this function is handling the normal memory, add the banks.
+     */
+    if ( mem == kernel_info_get_mem_const(kinfo) )
+        shm_mem_node_fill_reg_range(kinfo, reg, &nr_cells, addrcells,
+                                    sizecells);
+
+    for ( cells = reg, i = 0; cells < reg + nr_cells; i++, cells += reg_size )
+    {
+        uint64_t start = dt_read_number(cells, addrcells);
+        uint64_t size = dt_read_number(cells + addrcells, sizecells);
+
+        dt_dprintk("  Bank %u: %#"PRIx64"->%#"PRIx64"\n",
+                   i, start, start + size);
+    }
+
+    dt_dprintk("(reg size %d, nr cells %d)\n", reg_size, nr_cells);
+
+    res = fdt_property(fdt, "reg", reg, nr_cells * sizeof(*reg));
+    if ( res )
+        return res;
+
+    res = fdt_end_node(fdt);
+
+    return res;
+}
+
 /*
  * Local variables:
  * mode: C
-- 
2.52.0

Hi Oleksii,
> 
> diff --git a/xen/common/device-tree/domain-build.c b/xen/common/device-tree/domain-build.c
> index 774790aab3..6708c9dd66 100644
> --- a/xen/common/device-tree/domain-build.c
> +++ b/xen/common/device-tree/domain-build.c
> @@ -8,6 +8,7 @@
> #include <xen/mm.h>
> #include <xen/sched.h>
> #include <xen/sizes.h>
> +#include <xen/static-shmem.h>
> #include <xen/types.h>
> #include <xen/vmap.h>
> 
> @@ -451,6 +452,80 @@ int __init make_chosen_node(const struct kernel_info *kinfo)
>    return res;
> }
> 
> +int __init make_memory_node(const struct kernel_info *kinfo, int addrcells,
> +                            int sizecells, const struct membanks *mem)
> +{
> +    void *fdt = kinfo->fdt;
> +    unsigned int i;
> +    int res, reg_size = addrcells + sizecells;
> +    int nr_cells = 0;
> +    __be32 reg[DT_MEM_NODE_REG_RANGE_SIZE];
> +    __be32 *cells;
> +
> +    if ( mem->nr_banks == 0 )
> +        return -ENOENT;
> +
> +    /* find the first memory range that is reserved for device (or firmware) */
> +    for ( i = 0; i < mem->nr_banks &&
> +                 (mem->bank[i].type != MEMBANK_DEFAULT); i++ )
> +        ;

NIT: maybe we can fix the code style here, maintainers can give their opinion.

Changes looks good to me, I’ve also tested running on arm64 and arm32 FVP:

Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Tested-by: Luca Fancellu <luca.fancellu@arm.com>

Cheers,
Luca

On 28/11/2025 10:06, Luca Fancellu wrote:
> Hi Oleksii,
>>
>> diff --git a/xen/common/device-tree/domain-build.c b/xen/common/device-tree/domain-build.c
>> index 774790aab3..6708c9dd66 100644
>> --- a/xen/common/device-tree/domain-build.c
>> +++ b/xen/common/device-tree/domain-build.c
>> @@ -8,6 +8,7 @@
>> #include <xen/mm.h>
>> #include <xen/sched.h>
>> #include <xen/sizes.h>
>> +#include <xen/static-shmem.h>
>> #include <xen/types.h>
>> #include <xen/vmap.h>
>>
>> @@ -451,6 +452,80 @@ int __init make_chosen_node(const struct kernel_info *kinfo)
>>    return res;
>> }
>>
>> +int __init make_memory_node(const struct kernel_info *kinfo, int addrcells,
>> +                            int sizecells, const struct membanks *mem)
>> +{
>> +    void *fdt = kinfo->fdt;
>> +    unsigned int i;
>> +    int res, reg_size = addrcells + sizecells;
>> +    int nr_cells = 0;
>> +    __be32 reg[DT_MEM_NODE_REG_RANGE_SIZE];
>> +    __be32 *cells;
>> +
>> +    if ( mem->nr_banks == 0 )
>> +        return -ENOENT;
>> +
>> +    /* find the first memory range that is reserved for device (or firmware) */
>> +    for ( i = 0; i < mem->nr_banks &&
>> +                 (mem->bank[i].type != MEMBANK_DEFAULT); i++ )
>> +        ;
> 
> NIT: maybe we can fix the code style here, maintainers can give their opinion.
I'd prefer to keep the movement clean.

Acked-by: Michal Orzel <michal.orzel@amd.com>

~Michal