libnvdimm: Update persistence domain value for of_pmem and papr_scm device

Currently, kernel shows the below values
	"persistence_domain":"cpu_cache"
	"persistence_domain":"memory_controller"
	"persistence_domain":"unknown"

"cpu_cache" indicates no extra instructions is needed to ensure the persistence
of data in the pmem media on power failure.

"memory_controller" indicates cpu cache flush instructions are required to flush
the data. Platform provides mechanisms to automatically flush outstanding
write data from memory controler to pmem on system power loss.

Based on the above use memory_controller for non volatile regions on ppc64.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Link: https://lore.kernel.org/r/20200324034821.60869-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c
index 0b4467e..922a4fc 100644 (file)
--- a/arch/powerpc/platforms/pseries/papr_scm.c
+++ b/arch/powerpc/platforms/pseries/papr_scm.c
@@ -361,8 +361,10 @@ static int papr_scm_nvdimm_init(struct papr_scm_priv *p)
 
        if (p->is_volatile)
                p->region = nvdimm_volatile_region_create(p->bus, &ndr_desc);
-       else
+       else {
+               set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
                p->region = nvdimm_pmem_region_create(p->bus, &ndr_desc);
+       }
        if (!p->region) {
                dev_err(dev, "Error registering region %pR from %pOF\n",
                                ndr_desc.res, p->dn);

diff --git a/drivers/nvdimm/of_pmem.c b/drivers/nvdimm/of_pmem.c
index 8224d14..6826a27 100644 (file)
--- a/drivers/nvdimm/of_pmem.c
+++ b/drivers/nvdimm/of_pmem.c
@@ -62,8 +62,10 @@ static int of_pmem_region_probe(struct platform_device *pdev)
 
                if (is_volatile)
                        region = nvdimm_volatile_region_create(bus, &ndr_desc);
-               else
+               else {
+                       set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
                        region = nvdimm_pmem_region_create(bus, &ndr_desc);
+               }
 
                if (!region)
                        dev_warn(&pdev->dev, "Unable to register region %pR from %pOF\n",