[PATCH v2 13/13] xen/arm: List static shared memory regions as /memory nodes

[Luca Fancellu <luca.fancellu@arm.com>]

Currently Xen is not exporting the static shared memory regions
to the device tree as /memory node, this commit is fixing this
issue.

The static shared memory banks can be part of the memory range
available for the domain, so if they are overlapping with the
normal memory banks, they need to be merged together in order
to produce a /memory node with non overlapping ranges in 'reg'.

Given that now make_memory_node needs a parameter 'struct kernel_info'
in order to call the new function shm_mem_node_merge_reg_range,
take the occasion to remove the unused struct domain parameter.

Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
---
v2:
 - try to use make_memory_node, don't add overlapping ranges of
   memory, commit message changed.
v1:
 - new patch
---
---
 xen/arch/arm/dom0less-build.c           |  2 +-
 xen/arch/arm/domain_build.c             | 38 ++++++++++++++++++-------
 xen/arch/arm/include/asm/domain_build.h |  2 +-
 xen/arch/arm/include/asm/static-shmem.h | 18 ++++++++++++
 xen/arch/arm/static-shmem.c             | 26 +++++++++++++++++
 5 files changed, 73 insertions(+), 13 deletions(-)

diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c
index 51cf03221d56..74f053c242f4 100644
--- a/xen/arch/arm/dom0less-build.c
+++ b/xen/arch/arm/dom0less-build.c
@@ -642,7 +642,7 @@ static int __init prepare_dtb_domU(struct domain *d, struct kernel_info *kinfo)
     if ( ret )
         goto err;
 
-    ret = make_memory_node(d, kinfo->fdt, addrcells, sizecells,
+    ret = make_memory_node(kinfo, addrcells, sizecells,
                            kernel_info_get_mem(kinfo));
     if ( ret )
         goto err;
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 71eebfcf7e03..f9b749d0a068 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -757,15 +757,14 @@ int __init domain_fdt_begin_node(void *fdt, const char *name, uint64_t unit)
     return fdt_begin_node(fdt, buf);
 }
 
-int __init make_memory_node(const struct domain *d,
-                            void *fdt,
-                            int addrcells, int sizecells,
-                            const struct membanks *mem)
+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[NR_MEM_BANKS * 4 /* Worst case addrcells + sizecells */];
+    __be32 reg[DT_MEM_NODE_REG_RANGE_SIZE];
     __be32 *cells;
 
     if ( mem->nr_banks == 0 )
@@ -798,14 +797,32 @@ int __init make_memory_node(const struct domain *d,
         if ( mem->bank[i].type == MEMBANK_STATIC_DOMAIN )
             continue;
 
-        dt_dprintk("  Bank %d: %#"PRIx64"->%#"PRIx64"\n",
-                   i, start, start + size);
-
         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, merge the banks.
+     */
+    if ( mem == kernel_info_get_mem_const(kinfo) )
+    {
+        res = shm_mem_node_merge_reg_range(kinfo, reg, &nr_cells, addrcells,
+                                           sizecells);
+        if ( res )
+            return res;
+    }
+
+    for ( cells = reg, i = 0; cells < reg + nr_cells; i++, cells += reg_size )
+    {
+        u64 start = dt_read_number(cells, addrcells);
+        u64 size = dt_read_number(cells + addrcells, sizecells);
+
+        dt_dprintk("  Bank %d: %#"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));
@@ -1771,7 +1788,7 @@ static int __init handle_node(struct domain *d, struct kernel_info *kinfo,
         if ( res )
             return res;
 
-        res = make_memory_node(d, kinfo->fdt, addrcells, sizecells,
+        res = make_memory_node(kinfo, addrcells, sizecells,
                                kernel_info_get_mem(kinfo));
         if ( res )
             return res;
@@ -1782,8 +1799,7 @@ static int __init handle_node(struct domain *d, struct kernel_info *kinfo,
          */
         if ( reserved_mem->nr_banks > 0 )
         {
-            res = make_memory_node(d, kinfo->fdt, addrcells, sizecells,
-                                   reserved_mem);
+            res = make_memory_node(kinfo, addrcells, sizecells, reserved_mem);
             if ( res )
                 return res;
         }
diff --git a/xen/arch/arm/include/asm/domain_build.h b/xen/arch/arm/include/asm/domain_build.h
index 026d975da28e..45936212ca21 100644
--- a/xen/arch/arm/include/asm/domain_build.h
+++ b/xen/arch/arm/include/asm/domain_build.h
@@ -14,7 +14,7 @@ int make_chosen_node(const struct kernel_info *kinfo);
 int make_cpus_node(const struct domain *d, void *fdt);
 int make_hypervisor_node(struct domain *d, const struct kernel_info *kinfo,
                          int addrcells, int sizecells);
-int make_memory_node(const struct domain *d, void *fdt, int addrcells,
+int make_memory_node(const struct kernel_info *kinfo, int addrcells,
                      int sizecells, const struct membanks *mem);
 int make_psci_node(void *fdt);
 int make_timer_node(const struct kernel_info *kinfo);
diff --git a/xen/arch/arm/include/asm/static-shmem.h b/xen/arch/arm/include/asm/static-shmem.h
index 7495a91e7a31..bb5624c801af 100644
--- a/xen/arch/arm/include/asm/static-shmem.h
+++ b/xen/arch/arm/include/asm/static-shmem.h
@@ -3,10 +3,15 @@
 #ifndef __ASM_STATIC_SHMEM_H_
 #define __ASM_STATIC_SHMEM_H_
 
+#include <xen/types.h>
 #include <asm/kernel.h>
+#include <asm/setup.h>
 
 #ifdef CONFIG_STATIC_SHM
 
+/* Worst case /memory node reg element: (addrcells + sizecells) */
+#define DT_MEM_NODE_REG_RANGE_SIZE ((NR_MEM_BANKS + NR_SHMEM_BANKS) * 4)
+
 int make_resv_memory_node(const struct kernel_info *kinfo, int addrcells,
                           int sizecells);
 
@@ -37,8 +42,14 @@ int remove_shm_holes_for_domU(const struct kernel_info *kinfo,
 int make_shm_resv_memory_node(const struct kernel_info *kinfo, int addrcells,
                               int sizecells);
 
+int shm_mem_node_merge_reg_range(const struct kernel_info *kinfo, __be32 *reg,
+                                 int *nr_cells, int addrcells, int sizecells);
+
 #else /* !CONFIG_STATIC_SHM */
 
+/* Worst case /memory node reg element: (addrcells + sizecells) */
+#define DT_MEM_NODE_REG_RANGE_SIZE (NR_MEM_BANKS * 4)
+
 static inline int make_resv_memory_node(const struct kernel_info *kinfo,
                                         int addrcells, int sizecells)
 {
@@ -86,6 +97,13 @@ static inline int make_shm_resv_memory_node(const struct kernel_info *kinfo,
     return 0;
 }
 
+static inline int shm_mem_node_merge_reg_range(const struct kernel_info *kinfo,
+                                               __be32 *reg, int *nr_cells,
+                                               int addrcells, int sizecells)
+{
+    return 0;
+}
+
 #endif /* CONFIG_STATIC_SHM */
 
 #endif /* __ASM_STATIC_SHMEM_H_ */
diff --git a/xen/arch/arm/static-shmem.c b/xen/arch/arm/static-shmem.c
index 5ad6f1269c48..61fcbe217c61 100644
--- a/xen/arch/arm/static-shmem.c
+++ b/xen/arch/arm/static-shmem.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
+#include <xen/device_tree.h>
 #include <xen/libfdt/libfdt.h>
 #include <xen/rangeset.h>
 #include <xen/sched.h>
@@ -662,6 +663,31 @@ int __init remove_shm_holes_for_domU(const struct kernel_info *kinfo,
     return res;
 }
 
+int __init shm_mem_node_merge_reg_range(const struct kernel_info *kinfo,
+                                        __be32 *reg, int *nr_cells,
+                                        int addrcells, int sizecells)
+{
+    const struct membanks *mem = &kinfo->shm_mem.common;
+    unsigned int i;
+    __be32 *cells;
+
+    BUG_ON(!nr_cells || !reg);
+
+    cells = &reg[*nr_cells];
+    for ( i = 0; i < mem->nr_banks; i++ )
+    {
+        u64 start = mem->bank[i].start;
+        u64 size = mem->bank[i].size;
+
+        *nr_cells += addrcells + sizecells;
+        BUG_ON(*nr_cells >= DT_MEM_NODE_REG_RANGE_SIZE);
+        dt_child_set_range(&cells, addrcells, sizecells, start, size);
+    }
+
+    return dt_merge_overlapping_addr_size_intervals(reg, nr_cells, addrcells,
+                                                    sizecells);
+}
+
 /*
  * Local variables:
  * mode: C
-- 
2.34.1