3 files changed, 43 insertions, 29 deletions

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 114cf48085ab..4baeb853e0c3 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -410,6 +410,7 @@ config ACPI_NFIT
         tristate "ACPI NVDIMM Firmware Interface Table (NFIT)"
         depends on PHYS_ADDR_T_64BIT
         depends on BLK_DEV
+        depends on ARCH_HAS_MMIO_FLUSH
         select LIBNVDIMM
         help
           Infrastructure to probe ACPI 6 compliant platforms for
diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index 7c2638f914a9..56fff0141636 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -1017,7 +1017,7 @@ static u64 read_blk_stat(struct nfit_blk *nfit_blk, unsigned int bw)
         if (mmio->num_lines)
                 offset = to_interleave_offset(offset, mmio);
 
-        return readq(mmio->base + offset);
+        return readq(mmio->addr.base + offset);
 }
 
 static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
@@ -1042,11 +1042,11 @@ static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
         if (mmio->num_lines)
                 offset = to_interleave_offset(offset, mmio);
 
-        writeq(cmd, mmio->base + offset);
+        writeq(cmd, mmio->addr.base + offset);
         wmb_blk(nfit_blk);
 
         if (nfit_blk->dimm_flags & ND_BLK_DCR_LATCH)
-                readq(mmio->base + offset);
+                readq(mmio->addr.base + offset);
 }
 
 static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
@@ -1078,11 +1078,16 @@ static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
                 }
 
                 if (rw)
-                        memcpy_to_pmem(mmio->aperture + offset,
+                        memcpy_to_pmem(mmio->addr.aperture + offset,
                                         iobuf + copied, c);
-                else
+                else {
+                        if (nfit_blk->dimm_flags & ND_BLK_READ_FLUSH)
+                                mmio_flush_range((void __force *)
+                                        mmio->addr.aperture + offset, c);
+
                         memcpy_from_pmem(iobuf + copied,
-                                        mmio->aperture + offset, c);
+                                        mmio->addr.aperture + offset, c);
+                }
 
                 copied += c;
                 len -= c;
@@ -1129,7 +1134,10 @@ static void nfit_spa_mapping_release(struct kref *kref)
 
         WARN_ON(!mutex_is_locked(&acpi_desc->spa_map_mutex));
         dev_dbg(acpi_desc->dev, "%s: SPA%d\n", __func__, spa->range_index);
-        iounmap(spa_map->iomem);
+        if (spa_map->type == SPA_MAP_APERTURE)
+                memunmap((void __force *)spa_map->addr.aperture);
+        else
+                iounmap(spa_map->addr.base);
         release_mem_region(spa->address, spa->length);
         list_del(&spa_map->list);
         kfree(spa_map);
@@ -1175,7 +1183,7 @@ static void __iomem *__nfit_spa_map(struct acpi_nfit_desc *acpi_desc,
         spa_map = find_spa_mapping(acpi_desc, spa);
         if (spa_map) {
                 kref_get(&spa_map->kref);
-                return spa_map->iomem;
+                return spa_map->addr.base;
         }
 
         spa_map = kzalloc(sizeof(*spa_map), GFP_KERNEL);
@@ -1191,20 +1199,19 @@ static void __iomem *__nfit_spa_map(struct acpi_nfit_desc *acpi_desc,
         if (!res)
                 goto err_mem;
 
-        if (type == SPA_MAP_APERTURE) {
-                /*
-                 * TODO: memremap_pmem() support, but that requires cache
-                 * flushing when the aperture is moved.
-                 */
-                spa_map->iomem = ioremap_wc(start, n);
-        } else
-                spa_map->iomem = ioremap_nocache(start, n);
+        spa_map->type = type;
+        if (type == SPA_MAP_APERTURE)
+                spa_map->addr.aperture = (void __pmem *)memremap(start, n,
+                                                        ARCH_MEMREMAP_PMEM);
+        else
+                spa_map->addr.base = ioremap_nocache(start, n);
+
 
-        if (!spa_map->iomem)
+        if (!spa_map->addr.base)
                 goto err_map;
 
         list_add_tail(&spa_map->list, &acpi_desc->spa_maps);
-        return spa_map->iomem;
+        return spa_map->addr.base;
 
  err_map:
         release_mem_region(start, n);
@@ -1267,7 +1274,7 @@ static int acpi_nfit_blk_get_flags(struct nvdimm_bus_descriptor *nd_desc,
                 nfit_blk->dimm_flags = flags.flags;
         else if (rc == -ENOTTY) {
                 /* fall back to a conservative default */
-                nfit_blk->dimm_flags = ND_BLK_DCR_LATCH;
+                nfit_blk->dimm_flags = ND_BLK_DCR_LATCH | ND_BLK_READ_FLUSH;
                 rc = 0;
         } else
                 rc = -ENXIO;
@@ -1307,9 +1314,9 @@ static int acpi_nfit_blk_region_enable(struct nvdimm_bus *nvdimm_bus,
         /* map block aperture memory */
         nfit_blk->bdw_offset = nfit_mem->bdw->offset;
         mmio = &nfit_blk->mmio[BDW];
-        mmio->base = nfit_spa_map(acpi_desc, nfit_mem->spa_bdw,
+        mmio->addr.base = nfit_spa_map(acpi_desc, nfit_mem->spa_bdw,
                         SPA_MAP_APERTURE);
-        if (!mmio->base) {
+        if (!mmio->addr.base) {
                 dev_dbg(dev, "%s: %s failed to map bdw\n", __func__,
                                 nvdimm_name(nvdimm));
                 return -ENOMEM;
@@ -1330,9 +1337,9 @@ static int acpi_nfit_blk_region_enable(struct nvdimm_bus *nvdimm_bus,
         nfit_blk->cmd_offset = nfit_mem->dcr->command_offset;
         nfit_blk->stat_offset = nfit_mem->dcr->status_offset;
         mmio = &nfit_blk->mmio[DCR];
-        mmio->base = nfit_spa_map(acpi_desc, nfit_mem->spa_dcr,
+        mmio->addr.base = nfit_spa_map(acpi_desc, nfit_mem->spa_dcr,
                         SPA_MAP_CONTROL);
-        if (!mmio->base) {
+        if (!mmio->addr.base) {
                 dev_dbg(dev, "%s: %s failed to map dcr\n", __func__,
                                 nvdimm_name(nvdimm));
                 return -ENOMEM;
@@ -1399,7 +1406,7 @@ static void acpi_nfit_blk_region_disable(struct nvdimm_bus *nvdimm_bus,
         for (i = 0; i < 2; i++) {
                 struct nfit_blk_mmio *mmio = &nfit_blk->mmio[i];
 
-                if (mmio->base)
+                if (mmio->addr.base)
                         nfit_spa_unmap(acpi_desc, mmio->spa);
         }
         nd_blk_region_set_provider_data(ndbr, NULL);
diff --git a/drivers/acpi/nfit.h b/drivers/acpi/nfit.h
index f2c2bb751882..7e740156b9c2 100644
--- a/drivers/acpi/nfit.h
+++ b/drivers/acpi/nfit.h
@@ -41,6 +41,7 @@ enum nfit_uuids {
 };
 
 enum {
+        ND_BLK_READ_FLUSH = 1,
         ND_BLK_DCR_LATCH = 2,
 };
 
@@ -117,12 +118,16 @@ enum nd_blk_mmio_selector {
         DCR,
 };
 
+struct nd_blk_addr {
+        union {
+                void __iomem *base;
+                void __pmem  *aperture;
+        };
+};
+
 struct nfit_blk {
         struct nfit_blk_mmio {
-                union {
-                        void __iomem *base;
-                        void __pmem  *aperture;
-                };
+                struct nd_blk_addr addr;
                 u64 size;
                 u64 base_offset;
                 u32 line_size;
@@ -149,7 +154,8 @@ struct nfit_spa_mapping {
         struct acpi_nfit_system_address *spa;
         struct list_head list;
         struct kref kref;
-        void __iomem *iomem;
+        enum spa_map_type type;
+        struct nd_blk_addr addr;
 };
 
 static inline struct nfit_spa_mapping *to_spa_map(struct kref *kref)