+static u64 to_interleave_offset(u64 offset, struct nfit_blk_mmio *mmio)
+{
+ struct acpi_nfit_interleave *idt = mmio->idt;
+ u32 sub_line_offset, line_index, line_offset;
+ u64 line_no, table_skip_count, table_offset;
+
+ line_no = div_u64_rem(offset, mmio->line_size, &sub_line_offset);
+ table_skip_count = div_u64_rem(line_no, mmio->num_lines, &line_index);
+ line_offset = idt->line_offset[line_index]
+ * mmio->line_size;
+ table_offset = table_skip_count * mmio->table_size;
+
+ return mmio->base_offset + line_offset + table_offset + sub_line_offset;
+}
+
+static u64 read_blk_stat(struct nfit_blk *nfit_blk, unsigned int bw)
+{
+ struct nfit_blk_mmio *mmio = &nfit_blk->mmio[DCR];
+ u64 offset = nfit_blk->stat_offset + mmio->size * bw;
+
+ if (mmio->num_lines)
+ offset = to_interleave_offset(offset, mmio);
+
+ return readq(mmio->base + offset);
+}
+
+static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
+ resource_size_t dpa, unsigned int len, unsigned int write)
+{
+ u64 cmd, offset;
+ struct nfit_blk_mmio *mmio = &nfit_blk->mmio[DCR];
+
+ enum {
+ BCW_OFFSET_MASK = (1ULL << 48)-1,
+ BCW_LEN_SHIFT = 48,
+ BCW_LEN_MASK = (1ULL << 8) - 1,
+ BCW_CMD_SHIFT = 56,
+ };
+
+ cmd = (dpa >> L1_CACHE_SHIFT) & BCW_OFFSET_MASK;
+ len = len >> L1_CACHE_SHIFT;
+ cmd |= ((u64) len & BCW_LEN_MASK) << BCW_LEN_SHIFT;
+ cmd |= ((u64) write) << BCW_CMD_SHIFT;
+
+ offset = nfit_blk->cmd_offset + mmio->size * bw;
+ if (mmio->num_lines)
+ offset = to_interleave_offset(offset, mmio);
+
+ writeq(cmd, mmio->base + offset);
+ /* FIXME: conditionally perform read-back if mandated by firmware */
+}
+
+static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
+ resource_size_t dpa, void *iobuf, size_t len, int rw,
+ unsigned int lane)
+{
+ struct nfit_blk_mmio *mmio = &nfit_blk->mmio[BDW];
+ unsigned int copied = 0;
+ u64 base_offset;
+ int rc;
+
+ base_offset = nfit_blk->bdw_offset + dpa % L1_CACHE_BYTES
+ + lane * mmio->size;
+ /* TODO: non-temporal access, flush hints, cache management etc... */
+ write_blk_ctl(nfit_blk, lane, dpa, len, rw);
+ while (len) {
+ unsigned int c;
+ u64 offset;
+
+ if (mmio->num_lines) {
+ u32 line_offset;
+
+ offset = to_interleave_offset(base_offset + copied,
+ mmio);
+ div_u64_rem(offset, mmio->line_size, &line_offset);
+ c = min_t(size_t, len, mmio->line_size - line_offset);
+ } else {
+ offset = base_offset + nfit_blk->bdw_offset;
+ c = len;
+ }
+
+ if (rw)
+ memcpy(mmio->aperture + offset, iobuf + copied, c);
+ else
+ memcpy(iobuf + copied, mmio->aperture + offset, c);
+
+ copied += c;
+ len -= c;
+ }
+ rc = read_blk_stat(nfit_blk, lane) ? -EIO : 0;
+ return rc;
+}
+
+static int acpi_nfit_blk_region_do_io(struct nd_blk_region *ndbr,
+ resource_size_t dpa, void *iobuf, u64 len, int rw)
+{
+ struct nfit_blk *nfit_blk = nd_blk_region_provider_data(ndbr);
+ struct nfit_blk_mmio *mmio = &nfit_blk->mmio[BDW];
+ struct nd_region *nd_region = nfit_blk->nd_region;
+ unsigned int lane, copied = 0;
+ int rc = 0;
+
+ lane = nd_region_acquire_lane(nd_region);
+ while (len) {
+ u64 c = min(len, mmio->size);
+
+ rc = acpi_nfit_blk_single_io(nfit_blk, dpa + copied,
+ iobuf + copied, c, rw, lane);
+ if (rc)
+ break;
+
+ copied += c;
+ len -= c;
+ }
+ nd_region_release_lane(nd_region, lane);
+
+ return rc;
+}
+
+static void nfit_spa_mapping_release(struct kref *kref)
+{
+ struct nfit_spa_mapping *spa_map = to_spa_map(kref);
+ struct acpi_nfit_system_address *spa = spa_map->spa;
+ struct acpi_nfit_desc *acpi_desc = spa_map->acpi_desc;
+
+ 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);
+ release_mem_region(spa->address, spa->length);
+ list_del(&spa_map->list);
+ kfree(spa_map);
+}
+
+static struct nfit_spa_mapping *find_spa_mapping(
+ struct acpi_nfit_desc *acpi_desc,
+ struct acpi_nfit_system_address *spa)
+{
+ struct nfit_spa_mapping *spa_map;
+
+ WARN_ON(!mutex_is_locked(&acpi_desc->spa_map_mutex));
+ list_for_each_entry(spa_map, &acpi_desc->spa_maps, list)
+ if (spa_map->spa == spa)
+ return spa_map;
+
+ return NULL;
+}
+
+static void nfit_spa_unmap(struct acpi_nfit_desc *acpi_desc,
+ struct acpi_nfit_system_address *spa)
+{
+ struct nfit_spa_mapping *spa_map;
+
+ mutex_lock(&acpi_desc->spa_map_mutex);
+ spa_map = find_spa_mapping(acpi_desc, spa);
+
+ if (spa_map)
+ kref_put(&spa_map->kref, nfit_spa_mapping_release);
+ mutex_unlock(&acpi_desc->spa_map_mutex);
+}
+
+static void __iomem *__nfit_spa_map(struct acpi_nfit_desc *acpi_desc,
+ struct acpi_nfit_system_address *spa)
+{
+ resource_size_t start = spa->address;
+ resource_size_t n = spa->length;
+ struct nfit_spa_mapping *spa_map;
+ struct resource *res;
+
+ WARN_ON(!mutex_is_locked(&acpi_desc->spa_map_mutex));
+
+ spa_map = find_spa_mapping(acpi_desc, spa);
+ if (spa_map) {
+ kref_get(&spa_map->kref);
+ return spa_map->iomem;
+ }
+
+ spa_map = kzalloc(sizeof(*spa_map), GFP_KERNEL);
+ if (!spa_map)
+ return NULL;
+
+ INIT_LIST_HEAD(&spa_map->list);
+ spa_map->spa = spa;
+ kref_init(&spa_map->kref);
+ spa_map->acpi_desc = acpi_desc;
+
+ res = request_mem_region(start, n, dev_name(acpi_desc->dev));
+ if (!res)
+ goto err_mem;
+
+ /* TODO: cacheability based on the spa type */
+ spa_map->iomem = ioremap_nocache(start, n);
+ if (!spa_map->iomem)
+ goto err_map;
+
+ list_add_tail(&spa_map->list, &acpi_desc->spa_maps);
+ return spa_map->iomem;
+
+ err_map:
+ release_mem_region(start, n);
+ err_mem:
+ kfree(spa_map);
+ return NULL;
+}
+
+/**
+ * nfit_spa_map - interleave-aware managed-mappings of acpi_nfit_system_address ranges
+ * @nvdimm_bus: NFIT-bus that provided the spa table entry
+ * @nfit_spa: spa table to map
+ *
+ * In the case where block-data-window apertures and
+ * dimm-control-regions are interleaved they will end up sharing a
+ * single request_mem_region() + ioremap() for the address range. In
+ * the style of devm nfit_spa_map() mappings are automatically dropped
+ * when all region devices referencing the same mapping are disabled /
+ * unbound.
+ */
+static void __iomem *nfit_spa_map(struct acpi_nfit_desc *acpi_desc,
+ struct acpi_nfit_system_address *spa)
+{
+ void __iomem *iomem;
+
+ mutex_lock(&acpi_desc->spa_map_mutex);
+ iomem = __nfit_spa_map(acpi_desc, spa);
+ mutex_unlock(&acpi_desc->spa_map_mutex);
+
+ return iomem;
+}
+
+static int nfit_blk_init_interleave(struct nfit_blk_mmio *mmio,
+ struct acpi_nfit_interleave *idt, u16 interleave_ways)
+{
+ if (idt) {
+ mmio->num_lines = idt->line_count;
+ mmio->line_size = idt->line_size;
+ if (interleave_ways == 0)
+ return -ENXIO;
+ mmio->table_size = mmio->num_lines * interleave_ways
+ * mmio->line_size;
+ }
+
+ return 0;
+}
+
+static int acpi_nfit_blk_region_enable(struct nvdimm_bus *nvdimm_bus,
+ struct device *dev)
+{
+ struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
+ struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
+ struct nd_blk_region *ndbr = to_nd_blk_region(dev);
+ struct nfit_blk_mmio *mmio;
+ struct nfit_blk *nfit_blk;
+ struct nfit_mem *nfit_mem;
+ struct nvdimm *nvdimm;
+ int rc;
+
+ nvdimm = nd_blk_region_to_dimm(ndbr);
+ nfit_mem = nvdimm_provider_data(nvdimm);
+ if (!nfit_mem || !nfit_mem->dcr || !nfit_mem->bdw) {
+ dev_dbg(dev, "%s: missing%s%s%s\n", __func__,
+ nfit_mem ? "" : " nfit_mem",
+ nfit_mem->dcr ? "" : " dcr",
+ nfit_mem->bdw ? "" : " bdw");
+ return -ENXIO;
+ }
+
+ nfit_blk = devm_kzalloc(dev, sizeof(*nfit_blk), GFP_KERNEL);
+ if (!nfit_blk)
+ return -ENOMEM;
+ nd_blk_region_set_provider_data(ndbr, nfit_blk);
+ nfit_blk->nd_region = to_nd_region(dev);
+
+ /* 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);
+ if (!mmio->base) {
+ dev_dbg(dev, "%s: %s failed to map bdw\n", __func__,
+ nvdimm_name(nvdimm));
+ return -ENOMEM;
+ }
+ mmio->size = nfit_mem->bdw->size;
+ mmio->base_offset = nfit_mem->memdev_bdw->region_offset;
+ mmio->idt = nfit_mem->idt_bdw;
+ mmio->spa = nfit_mem->spa_bdw;
+ rc = nfit_blk_init_interleave(mmio, nfit_mem->idt_bdw,
+ nfit_mem->memdev_bdw->interleave_ways);
+ if (rc) {
+ dev_dbg(dev, "%s: %s failed to init bdw interleave\n",
+ __func__, nvdimm_name(nvdimm));
+ return rc;
+ }
+
+ /* map block control memory */
+ 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);
+ if (!mmio->base) {
+ dev_dbg(dev, "%s: %s failed to map dcr\n", __func__,
+ nvdimm_name(nvdimm));
+ return -ENOMEM;
+ }
+ mmio->size = nfit_mem->dcr->window_size;
+ mmio->base_offset = nfit_mem->memdev_dcr->region_offset;
+ mmio->idt = nfit_mem->idt_dcr;
+ mmio->spa = nfit_mem->spa_dcr;
+ rc = nfit_blk_init_interleave(mmio, nfit_mem->idt_dcr,
+ nfit_mem->memdev_dcr->interleave_ways);
+ if (rc) {
+ dev_dbg(dev, "%s: %s failed to init dcr interleave\n",
+ __func__, nvdimm_name(nvdimm));
+ return rc;
+ }
+
+ if (mmio->line_size == 0)
+ return 0;
+
+ if ((u32) nfit_blk->cmd_offset % mmio->line_size
+ + 8 > mmio->line_size) {
+ dev_dbg(dev, "cmd_offset crosses interleave boundary\n");
+ return -ENXIO;
+ } else if ((u32) nfit_blk->stat_offset % mmio->line_size
+ + 8 > mmio->line_size) {
+ dev_dbg(dev, "stat_offset crosses interleave boundary\n");
+ return -ENXIO;
+ }
+
+ return 0;
+}
+
+static void acpi_nfit_blk_region_disable(struct nvdimm_bus *nvdimm_bus,
+ struct device *dev)
+{
+ struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
+ struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
+ struct nd_blk_region *ndbr = to_nd_blk_region(dev);
+ struct nfit_blk *nfit_blk = nd_blk_region_provider_data(ndbr);
+ int i;
+
+ if (!nfit_blk)
+ return; /* never enabled */
+
+ /* auto-free BLK spa mappings */
+ for (i = 0; i < 2; i++) {
+ struct nfit_blk_mmio *mmio = &nfit_blk->mmio[i];
+
+ if (mmio->base)
+ nfit_spa_unmap(acpi_desc, mmio->spa);
+ }
+ nd_blk_region_set_provider_data(ndbr, NULL);
+ /* devm will free nfit_blk */
+}
+