1 files changed, 75 insertions, 4 deletions

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 33f71983e001..ed3d2d1a7ae9 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -11,6 +11,7 @@
 #define pr_fmt(fmt)	"ACPI: IORT: " fmt
 
 #include <linux/acpi_iort.h>
+#include <linux/bitfield.h>
 #include <linux/iommu.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -298,6 +299,59 @@ out:
 	return status;
 }
 
+struct iort_workaround_oem_info {
+	char oem_id[ACPI_OEM_ID_SIZE + 1];
+	char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1];
+	u32 oem_revision;
+};
+
+static bool apply_id_count_workaround;
+
+static struct iort_workaround_oem_info wa_info[] __initdata = {
+	{
+		.oem_id		= "HISI  ",
+		.oem_table_id	= "HIP07   ",
+		.oem_revision	= 0,
+	}, {
+		.oem_id		= "HISI  ",
+		.oem_table_id	= "HIP08   ",
+		.oem_revision	= 0,
+	}
+};
+
+static void __init
+iort_check_id_count_workaround(struct acpi_table_header *tbl)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(wa_info); i++) {
+		if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) &&
+		    !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) &&
+		    wa_info[i].oem_revision == tbl->oem_revision) {
+			apply_id_count_workaround = true;
+			pr_warn(FW_BUG "ID count for ID mapping entry is wrong, applying workaround\n");
+			break;
+		}
+	}
+}
+
+static inline u32 iort_get_map_max(struct acpi_iort_id_mapping *map)
+{
+	u32 map_max = map->input_base + map->id_count;
+
+	/*
+	 * The IORT specification revision D (Section 3, table 4, page 9) says
+	 * Number of IDs = The number of IDs in the range minus one, but the
+	 * IORT code ignored the "minus one", and some firmware did that too,
+	 * so apply a workaround here to keep compatible with both the spec
+	 * compliant and non-spec compliant firmwares.
+	 */
+	if (apply_id_count_workaround)
+		map_max--;
+
+	return map_max;
+}
+
 static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in,
 		       u32 *rid_out)
 {
@@ -314,8 +368,7 @@ static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in,
 		return -ENXIO;
 	}
 
-	if (rid_in < map->input_base ||
-	    (rid_in >= map->input_base + map->id_count))
+	if (rid_in < map->input_base || rid_in > iort_get_map_max(map))
 		return -ENXIO;
 
 	*rid_out = map->output_base + (rid_in - map->input_base);
@@ -850,9 +903,9 @@ static inline bool iort_iommu_driver_enabled(u8 type)
 {
 	switch (type) {
 	case ACPI_IORT_NODE_SMMU_V3:
-		return IS_BUILTIN(CONFIG_ARM_SMMU_V3);
+		return IS_ENABLED(CONFIG_ARM_SMMU_V3);
 	case ACPI_IORT_NODE_SMMU:
-		return IS_BUILTIN(CONFIG_ARM_SMMU);
+		return IS_ENABLED(CONFIG_ARM_SMMU);
 	default:
 		pr_warn("IORT node type %u does not describe an SMMU\n", type);
 		return false;
@@ -924,6 +977,20 @@ static int iort_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
 	return iort_iommu_xlate(info->dev, parent, streamid);
 }
 
+static void iort_named_component_init(struct device *dev,
+				      struct acpi_iort_node *node)
+{
+	struct acpi_iort_named_component *nc;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
+
+	if (!fwspec)
+		return;
+
+	nc = (struct acpi_iort_named_component *)node->node_data;
+	fwspec->num_pasid_bits = FIELD_GET(ACPI_IORT_NC_PASID_BITS,
+					   nc->node_flags);
+}
+
 /**
  * iort_iommu_configure - Set-up IOMMU configuration for a device.
  *
@@ -978,6 +1045,9 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
 			if (parent)
 				err = iort_iommu_xlate(dev, parent, streamid);
 		} while (parent && !err);
+
+		if (!err)
+			iort_named_component_init(dev, node);
 	}
 
 	/*
@@ -1631,5 +1701,6 @@ void __init acpi_iort_init(void)
 		return;
 	}
 
+	iort_check_id_count_workaround(iort_table);
 	iort_init_platform_devices();
 }