VisionFive2 Linux kernel

diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index e11c00b2dc1e..0eccc29f5573 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -375,6 +375,7 @@ static DEFINE_SPINLOCK(direct_window_list_lock);
 /* protects initializing window twice for same device */
 static DEFINE_MUTEX(direct_window_init_mutex);
 #define DIRECT64_PROPNAME "linux,direct64-ddr-window-info"
+#define DMA64_PROPNAME "linux,dma64-ddr-window-info"
 
 static int tce_clearrange_multi_pSeriesLP(unsigned long start_pfn,
 					unsigned long num_pfn, const void *arg)
@@ -940,6 +941,7 @@ static int find_existing_ddw_windows(void)
 		return 0;
 
 	find_existing_ddw_windows_named(DIRECT64_PROPNAME);
+	find_existing_ddw_windows_named(DMA64_PROPNAME);
 
 	return 0;
 }
@@ -1226,14 +1228,17 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
 	struct ddw_create_response create;
 	int page_shift;
 	u64 win_addr;
+	const char *win_name;
 	struct device_node *dn;
 	u32 ddw_avail[DDW_APPLICABLE_SIZE];
 	struct direct_window *window;
 	struct property *win64;
 	bool ddw_enabled = false;
 	struct failed_ddw_pdn *fpdn;
-	bool default_win_removed = false;
+	bool default_win_removed = false, direct_mapping = false;
 	bool pmem_present;
+	struct pci_dn *pci = PCI_DN(pdn);
+	struct iommu_table *tbl = pci->table_group->tables[0];
 
 	dn = of_find_node_by_type(NULL, "ibm,pmemory");
 	pmem_present = dn != NULL;
@@ -1242,6 +1247,7 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
 	mutex_lock(&direct_window_init_mutex);
 
 	if (find_existing_ddw(pdn, &dev->dev.archdata.dma_offset, &len)) {
+		direct_mapping = (len >= max_ram_len);
 		ddw_enabled = true;
 		goto out_unlock;
 	}
@@ -1322,8 +1328,8 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
 			  query.page_size);
 		goto out_failed;
 	}
-	/* verify the window * number of ptes will map the partition */
-	/* check largest block * page size > max memory hotplug addr */
+
+
 	/*
 	 * The "ibm,pmemory" can appear anywhere in the address space.
 	 * Assuming it is still backed by page structs, try MAX_PHYSMEM_BITS
@@ -1339,13 +1345,25 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
 			dev_info(&dev->dev, "Skipping ibm,pmemory");
 	}
 
+	/* check if the available block * number of ptes will map everything */
 	if (query.largest_available_block < (1ULL << (len - page_shift))) {
 		dev_dbg(&dev->dev,
 			"can't map partition max 0x%llx with %llu %llu-sized pages\n",
 			1ULL << len,
 			query.largest_available_block,
 			1ULL << page_shift);
-		goto out_failed;
+
+		/* DDW + IOMMU on single window may fail if there is any allocation */
+		if (default_win_removed && iommu_table_in_use(tbl)) {
+			dev_dbg(&dev->dev, "current IOMMU table in use, can't be replaced.\n");
+			goto out_failed;
+		}
+
+		len = order_base_2(query.largest_available_block << page_shift);
+		win_name = DMA64_PROPNAME;
+	} else {
+		direct_mapping = true;
+		win_name = DIRECT64_PROPNAME;
 	}
 
 	ret = create_ddw(dev, ddw_avail, &create, page_shift, len);
@@ -1356,8 +1374,8 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
 		  create.liobn, dn);
 
 	win_addr = ((u64)create.addr_hi << 32) | create.addr_lo;
-	win64 = ddw_property_create(DIRECT64_PROPNAME, create.liobn, win_addr,
-				    page_shift, len);
+	win64 = ddw_property_create(win_name, create.liobn, win_addr, page_shift, len);
+
 	if (!win64) {
 		dev_info(&dev->dev,
 			 "couldn't allocate property, property name, or value\n");
@@ -1375,15 +1393,54 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn)
 	if (!window)
 		goto out_del_prop;
 
-	ret = walk_system_ram_range(0, memblock_end_of_DRAM() >> PAGE_SHIFT,
-			win64->value, tce_setrange_multi_pSeriesLP_walk);
-	if (ret) {
-		dev_info(&dev->dev, "failed to map direct window for %pOF: %d\n",
-			 dn, ret);
+	if (direct_mapping) {
+		/* DDW maps the whole partition, so enable direct DMA mapping */
+		ret = walk_system_ram_range(0, memblock_end_of_DRAM() >> PAGE_SHIFT,
+					    win64->value, tce_setrange_multi_pSeriesLP_walk);
+		if (ret) {
+			dev_info(&dev->dev, "failed to map direct window for %pOF: %d\n",
+				 dn, ret);
 
 		/* Make sure to clean DDW if any TCE was set*/
 		clean_dma_window(pdn, win64->value);
-		goto out_del_list;
+			goto out_del_list;
+		}
+	} else {
+		struct iommu_table *newtbl;
+		int i;
+
+		for (i = 0; i < ARRAY_SIZE(pci->phb->mem_resources); i++) {
+			const unsigned long mask = IORESOURCE_MEM_64 | IORESOURCE_MEM;
+
+			/* Look for MMIO32 */
+			if ((pci->phb->mem_resources[i].flags & mask) == IORESOURCE_MEM)
+				break;
+		}
+
+		if (i == ARRAY_SIZE(pci->phb->mem_resources))
+			goto out_del_list;
+
+		/* New table for using DDW instead of the default DMA window */
+		newtbl = iommu_pseries_alloc_table(pci->phb->node);
+		if (!newtbl) {
+			dev_dbg(&dev->dev, "couldn't create new IOMMU table\n");
+			goto out_del_list;
+		}
+
+		iommu_table_setparms_common(newtbl, pci->phb->bus->number, create.liobn, win_addr,
+					    1UL << len, page_shift, NULL, &iommu_table_lpar_multi_ops);
+		iommu_init_table(newtbl, pci->phb->node, pci->phb->mem_resources[i].start,
+				 pci->phb->mem_resources[i].end);
+
+		pci->table_group->tables[1] = newtbl;
+
+		/* Keep default DMA window stuct if removed */
+		if (default_win_removed) {
+			tbl->it_size = 0;
+			kfree(tbl->it_map);
+		}
+
+		set_iommu_table_base(&dev->dev, newtbl);
 	}
 
 	spin_lock(&direct_window_list_lock);
@@ -1427,10 +1484,10 @@ out_unlock:
 	 * as RAM, then we failed to create a window to cover persistent
 	 * memory and need to set the DMA limit.
 	 */
-	if (pmem_present && ddw_enabled && (len == max_ram_len))
+	if (pmem_present && ddw_enabled && direct_mapping && len == max_ram_len)
 		dev->dev.bus_dma_limit = dev->dev.archdata.dma_offset + (1ULL << len);
 
-	return ddw_enabled;
+    return ddw_enabled && direct_mapping;
 }
 
 static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev)
@@ -1572,7 +1629,9 @@ static int iommu_reconfig_notifier(struct notifier_block *nb, unsigned long acti
 		 * we have to remove the property when releasing
 		 * the device node.
 		 */
-		remove_ddw(np, false, DIRECT64_PROPNAME);
+		if (remove_ddw(np, false, DIRECT64_PROPNAME))
+			remove_ddw(np, false, DMA64_PROPNAME);
+
 		if (pci && pci->table_group)
 			iommu_pseries_free_group(pci->table_group,
 					np->full_name);