ppc/spapr: init lrdr-capapcity phys with ram size if maxmem not provided

lrdr-capacity contains phys field which communicates the maximum address
in bytes and therefore, the most memory that can be allocated to this
partition. This is usually populated when maxmem is provided alongwith
memory size on qemu command line. However since maxmem is an optional
param, this leads to bits being set to 0 in absence of maxmem param.
Fix this by initializing the respective bits as per total mem size in
such case.

Reported-by: Gaurav Batra <gbatra@us.ibm.com>
Tested-by: David Christensen <drc@linux.ibm.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Link: https://lore.kernel.org/r/20250506042903.76250-1-harshpb@linux.ibm.com
Message-ID: <20250506042903.76250-1-harshpb@linux.ibm.com>

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index eb22333404d37b41597374c41c23552da865edf2..82fb23beaa8d608ec5bc070b4a12263f5182a933 100644 (file)
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -907,6 +907,7 @@ static void spapr_dt_rtas(SpaprMachineState *spapr, void *fdt)
     int rtas;
     GString *hypertas = g_string_sized_new(256);
     GString *qemu_hypertas = g_string_sized_new(256);
+    uint64_t max_device_addr = 0;
     uint32_t lrdr_capacity[] = {
         0,
         0,
@@ -917,13 +918,15 @@ static void spapr_dt_rtas(SpaprMachineState *spapr, void *fdt)
 
     /* Do we have device memory? */
     if (MACHINE(spapr)->device_memory) {
-        uint64_t max_device_addr = MACHINE(spapr)->device_memory->base +
+        max_device_addr = MACHINE(spapr)->device_memory->base +
             memory_region_size(&MACHINE(spapr)->device_memory->mr);
-
-        lrdr_capacity[0] = cpu_to_be32(max_device_addr >> 32);
-        lrdr_capacity[1] = cpu_to_be32(max_device_addr & 0xffffffff);
+    } else if (ms->ram_size == ms->maxram_size) {
+        max_device_addr = ms->ram_size;
     }
 
+    lrdr_capacity[0] = cpu_to_be32(max_device_addr >> 32);
+    lrdr_capacity[1] = cpu_to_be32(max_device_addr & 0xffffffff);
+
     _FDT(rtas = fdt_add_subnode(fdt, 0, "rtas"));
 
     /* hypertas */