According to CXL 3.1 specification, 8.1.3.8 DVSEC CXL Range Registers "A
CXL.mem-capable device is permitted to report zero memory size."
This patch will allow a CXL type3 device to be initialized with zero memory
size, when there is no memory device property provided ( neither volatile,
persistent, nor dynamic region).
Signed-off-by: Hongjian Fan <hongjian....@seagate.com>
---
hw/mem/cxl_type3.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index 5cf754b38f..35caa186ca 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -159,7 +159,12 @@ static int ct3_build_cdat_table(CDATSubHeader
***cdat_table, void *priv)
int len = 0;
if (!ct3d->hostpmem && !ct3d->hostvmem && !ct3d->dc.num_regions) {
- return 0;
+ // zero memory size device. Build one entry with size 0
+ table = g_malloc0(CT3_CDAT_NUM_ENTRIES * sizeof(*table));
+ ct3_build_cdat_entries_for_mr(&(table[0]), dsmad_handle++,
+ 0, false, false, 0);
+ *cdat_table = g_steal_pointer(&table);
+ return CT3_CDAT_NUM_ENTRIES;
}
if (ct3d->hostvmem) {
@@ -712,8 +717,11 @@ static bool cxl_setup_memory(CXLType3Dev *ct3d, Error
**errp)
if (!ct3d->hostmem && !ct3d->hostvmem && !ct3d->hostpmem
&& !ct3d->dc.num_regions) {
- error_setg(errp, "at least one memdev property must be set");
- return false;
+ // no memdev property provided. Default to zero memory size device
+ ct3d->cxl_dstate.pmem_size = 0;
+ ct3d->cxl_dstate.vmem_size = 0;
+ ct3d->cxl_dstate.static_mem_size = 0;
+ return true;
} else if (ct3d->hostmem && ct3d->hostpmem) {
error_setg(errp, "[memdev] cannot be used with new "
"[persistent-memdev] property");
--
2.25.1
