1 files changed, 247 insertions, 74 deletions

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 62e54f1a248b..e05673bcd52b 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -6,6 +6,7 @@
 
 #include <linux/acpi.h>
 #include <linux/acpi_iort.h>
+#include <linux/bitfield.h>
 #include <linux/bitmap.h>
 #include <linux/cpu.h>
 #include <linux/crash_dump.h>
@@ -102,20 +103,21 @@ struct its_node {
 	struct its_collection	*collections;
 	struct fwnode_handle	*fwnode_handle;
 	u64			(*get_msi_base)(struct its_device *its_dev);
+	u64			typer;
 	u64			cbaser_save;
 	u32			ctlr_save;
 	struct list_head	its_device_list;
 	u64			flags;
 	unsigned long		list_nr;
-	u32			ite_size;
-	u32			device_ids;
 	int			numa_node;
 	unsigned int		msi_domain_flags;
 	u32			pre_its_base; /* for Socionext Synquacer */
-	bool			is_v4;
 	int			vlpi_redist_offset;
 };
 
+#define is_v4(its)		(!!((its)->typer & GITS_TYPER_VLPIS))
+#define device_ids(its)		(FIELD_GET(GITS_TYPER_DEVBITS, (its)->typer) + 1)
+
 #define ITS_ITT_ALIGN		SZ_256
 
 /* The maximum number of VPEID bits supported by VLPI commands */
@@ -130,7 +132,7 @@ struct event_lpi_map {
 	u16			*col_map;
 	irq_hw_number_t		lpi_base;
 	int			nr_lpis;
-	struct mutex		vlpi_lock;
+	raw_spinlock_t		vlpi_lock;
 	struct its_vm		*vm;
 	struct its_vlpi_map	*vlpi_maps;
 	int			nr_vlpis;
@@ -175,6 +177,28 @@ static DEFINE_IDA(its_vpeid_ida);
 #define gic_data_rdist_rd_base()	(gic_data_rdist()->rd_base)
 #define gic_data_rdist_vlpi_base()	(gic_data_rdist_rd_base() + SZ_128K)
 
+static u16 get_its_list(struct its_vm *vm)
+{
+	struct its_node *its;
+	unsigned long its_list = 0;
+
+	list_for_each_entry(its, &its_nodes, entry) {
+		if (!is_v4(its))
+			continue;
+
+		if (vm->vlpi_count[its->list_nr])
+			__set_bit(its->list_nr, &its_list);
+	}
+
+	return (u16)its_list;
+}
+
+static inline u32 its_get_event_id(struct irq_data *d)
+{
+	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+	return d->hwirq - its_dev->event_map.lpi_base;
+}
+
 static struct its_collection *dev_event_to_col(struct its_device *its_dev,
 					       u32 event)
 {
@@ -183,6 +207,22 @@ static struct its_collection *dev_event_to_col(struct its_device *its_dev,
 	return its->collections + its_dev->event_map.col_map[event];
 }
 
+static struct its_vlpi_map *dev_event_to_vlpi_map(struct its_device *its_dev,
+					       u32 event)
+{
+	if (WARN_ON_ONCE(event >= its_dev->event_map.nr_lpis))
+		return NULL;
+
+	return &its_dev->event_map.vlpi_maps[event];
+}
+
+static struct its_collection *irq_to_col(struct irq_data *d)
+{
+	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+
+	return dev_event_to_col(its_dev, its_get_event_id(d));
+}
+
 static struct its_collection *valid_col(struct its_collection *col)
 {
 	if (WARN_ON_ONCE(col->target_address & GENMASK_ULL(15, 0)))
@@ -289,7 +329,10 @@ struct its_cmd_desc {
  * The ITS command block, which is what the ITS actually parses.
  */
 struct its_cmd_block {
-	u64	raw_cmd[4];
+	union {
+		u64	raw_cmd[4];
+		__le64	raw_cmd_le[4];
+	};
 };
 
 #define ITS_CMD_QUEUE_SZ		SZ_64K
@@ -398,10 +441,10 @@ static void its_encode_vpt_size(struct its_cmd_block *cmd, u8 vpt_size)
 static inline void its_fixup_cmd(struct its_cmd_block *cmd)
 {
 	/* Let's fixup BE commands */
-	cmd->raw_cmd[0] = cpu_to_le64(cmd->raw_cmd[0]);
-	cmd->raw_cmd[1] = cpu_to_le64(cmd->raw_cmd[1]);
-	cmd->raw_cmd[2] = cpu_to_le64(cmd->raw_cmd[2]);
-	cmd->raw_cmd[3] = cpu_to_le64(cmd->raw_cmd[3]);
+	cmd->raw_cmd_le[0] = cpu_to_le64(cmd->raw_cmd[0]);
+	cmd->raw_cmd_le[1] = cpu_to_le64(cmd->raw_cmd[1]);
+	cmd->raw_cmd_le[2] = cpu_to_le64(cmd->raw_cmd[2]);
+	cmd->raw_cmd_le[3] = cpu_to_le64(cmd->raw_cmd[3]);
 }
 
 static struct its_collection *its_build_mapd_cmd(struct its_node *its,
@@ -660,6 +703,60 @@ static struct its_vpe *its_build_vmovp_cmd(struct its_node *its,
 	return valid_vpe(its, desc->its_vmovp_cmd.vpe);
 }
 
+static struct its_vpe *its_build_vinv_cmd(struct its_node *its,
+					  struct its_cmd_block *cmd,
+					  struct its_cmd_desc *desc)
+{
+	struct its_vlpi_map *map;
+
+	map = dev_event_to_vlpi_map(desc->its_inv_cmd.dev,
+				    desc->its_inv_cmd.event_id);
+
+	its_encode_cmd(cmd, GITS_CMD_INV);
+	its_encode_devid(cmd, desc->its_inv_cmd.dev->device_id);
+	its_encode_event_id(cmd, desc->its_inv_cmd.event_id);
+
+	its_fixup_cmd(cmd);
+
+	return valid_vpe(its, map->vpe);
+}
+
+static struct its_vpe *its_build_vint_cmd(struct its_node *its,
+					  struct its_cmd_block *cmd,
+					  struct its_cmd_desc *desc)
+{
+	struct its_vlpi_map *map;
+
+	map = dev_event_to_vlpi_map(desc->its_int_cmd.dev,
+				    desc->its_int_cmd.event_id);
+
+	its_encode_cmd(cmd, GITS_CMD_INT);
+	its_encode_devid(cmd, desc->its_int_cmd.dev->device_id);
+	its_encode_event_id(cmd, desc->its_int_cmd.event_id);
+
+	its_fixup_cmd(cmd);
+
+	return valid_vpe(its, map->vpe);
+}
+
+static struct its_vpe *its_build_vclear_cmd(struct its_node *its,
+					    struct its_cmd_block *cmd,
+					    struct its_cmd_desc *desc)
+{
+	struct its_vlpi_map *map;
+
+	map = dev_event_to_vlpi_map(desc->its_clear_cmd.dev,
+				    desc->its_clear_cmd.event_id);
+
+	its_encode_cmd(cmd, GITS_CMD_CLEAR);
+	its_encode_devid(cmd, desc->its_clear_cmd.dev->device_id);
+	its_encode_event_id(cmd, desc->its_clear_cmd.event_id);
+
+	its_fixup_cmd(cmd);
+
+	return valid_vpe(its, map->vpe);
+}
+
 static u64 its_cmd_ptr_to_offset(struct its_node *its,
 				 struct its_cmd_block *ptr)
 {
@@ -937,7 +1034,7 @@ static void its_send_invall(struct its_node *its, struct its_collection *col)
 
 static void its_send_vmapti(struct its_device *dev, u32 id)
 {
-	struct its_vlpi_map *map = &dev->event_map.vlpi_maps[id];
+	struct its_vlpi_map *map = dev_event_to_vlpi_map(dev, id);
 	struct its_cmd_desc desc;
 
 	desc.its_vmapti_cmd.vpe = map->vpe;
@@ -951,7 +1048,7 @@ static void its_send_vmapti(struct its_device *dev, u32 id)
 
 static void its_send_vmovi(struct its_device *dev, u32 id)
 {
-	struct its_vlpi_map *map = &dev->event_map.vlpi_maps[id];
+	struct its_vlpi_map *map = dev_event_to_vlpi_map(dev, id);
 	struct its_cmd_desc desc;
 
 	desc.its_vmovi_cmd.vpe = map->vpe;
@@ -976,17 +1073,15 @@ static void its_send_vmapp(struct its_node *its,
 
 static void its_send_vmovp(struct its_vpe *vpe)
 {
-	struct its_cmd_desc desc;
+	struct its_cmd_desc desc = {};
 	struct its_node *its;
 	unsigned long flags;
 	int col_id = vpe->col_idx;
 
 	desc.its_vmovp_cmd.vpe = vpe;
-	desc.its_vmovp_cmd.its_list = (u16)its_list_map;
 
 	if (!its_list_map) {
 		its = list_first_entry(&its_nodes, struct its_node, entry);
-		desc.its_vmovp_cmd.seq_num = 0;
 		desc.its_vmovp_cmd.col = &its->collections[col_id];
 		its_send_single_vcommand(its, its_build_vmovp_cmd, &desc);
 		return;
@@ -1003,10 +1098,11 @@ static void its_send_vmovp(struct its_vpe *vpe)
 	raw_spin_lock_irqsave(&vmovp_lock, flags);
 
 	desc.its_vmovp_cmd.seq_num = vmovp_seq_num++;
+	desc.its_vmovp_cmd.its_list = get_its_list(vpe->its_vm);
 
 	/* Emit VMOVPs */
 	list_for_each_entry(its, &its_nodes, entry) {
-		if (!its->is_v4)
+		if (!is_v4(its))
 			continue;
 
 		if (!vpe->its_vm->vlpi_count[its->list_nr])
@@ -1027,29 +1123,71 @@ static void its_send_vinvall(struct its_node *its, struct its_vpe *vpe)
 	its_send_single_vcommand(its, its_build_vinvall_cmd, &desc);
 }
 
+static void its_send_vinv(struct its_device *dev, u32 event_id)
+{
+	struct its_cmd_desc desc;
+
+	/*
+	 * There is no real VINV command. This is just a normal INV,
+	 * with a VSYNC instead of a SYNC.
+	 */
+	desc.its_inv_cmd.dev = dev;
+	desc.its_inv_cmd.event_id = event_id;
+
+	its_send_single_vcommand(dev->its, its_build_vinv_cmd, &desc);
+}
+
+static void its_send_vint(struct its_device *dev, u32 event_id)
+{
+	struct its_cmd_desc desc;
+
+	/*
+	 * There is no real VINT command. This is just a normal INT,
+	 * with a VSYNC instead of a SYNC.
+	 */
+	desc.its_int_cmd.dev = dev;
+	desc.its_int_cmd.event_id = event_id;
+
+	its_send_single_vcommand(dev->its, its_build_vint_cmd, &desc);
+}
+
+static void its_send_vclear(struct its_device *dev, u32 event_id)
+{
+	struct its_cmd_desc desc;
+
+	/*
+	 * There is no real VCLEAR command. This is just a normal CLEAR,
+	 * with a VSYNC instead of a SYNC.
+	 */
+	desc.its_clear_cmd.dev = dev;
+	desc.its_clear_cmd.event_id = event_id;
+
+	its_send_single_vcommand(dev->its, its_build_vclear_cmd, &desc);
+}
+
 /*
  * irqchip functions - assumes MSI, mostly.
  */
-
-static inline u32 its_get_event_id(struct irq_data *d)
+static struct its_vlpi_map *get_vlpi_map(struct irq_data *d)
 {
 	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
-	return d->hwirq - its_dev->event_map.lpi_base;
+	u32 event = its_get_event_id(d);
+
+	if (!irqd_is_forwarded_to_vcpu(d))
+		return NULL;
+
+	return dev_event_to_vlpi_map(its_dev, event);
 }
 
 static void lpi_write_config(struct irq_data *d, u8 clr, u8 set)
 {
+	struct its_vlpi_map *map = get_vlpi_map(d);
 	irq_hw_number_t hwirq;
 	void *va;
 	u8 *cfg;
 
-	if (irqd_is_forwarded_to_vcpu(d)) {
-		struct its_device *its_dev = irq_data_get_irq_chip_data(d);
-		u32 event = its_get_event_id(d);
-		struct its_vlpi_map *map;
-
-		va = page_address(its_dev->event_map.vm->vprop_page);
-		map = &its_dev->event_map.vlpi_maps[event];
+	if (map) {
+		va = page_address(map->vm->vprop_page);
 		hwirq = map->vintid;
 
 		/* Remember the updated property */
@@ -1075,23 +1213,50 @@ static void lpi_write_config(struct irq_data *d, u8 clr, u8 set)
 		dsb(ishst);
 }
 
+static void wait_for_syncr(void __iomem *rdbase)
+{
+	while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
+		cpu_relax();
+}
+
+static void direct_lpi_inv(struct irq_data *d)
+{
+	struct its_collection *col;
+	void __iomem *rdbase;
+
+	/* Target the redistributor this LPI is currently routed to */
+	col = irq_to_col(d);
+	rdbase = per_cpu_ptr(gic_rdists->rdist, col->col_id)->rd_base;
+	gic_write_lpir(d->hwirq, rdbase + GICR_INVLPIR);
+
+	wait_for_syncr(rdbase);
+}
+
 static void lpi_update_config(struct irq_data *d, u8 clr, u8 set)
 {
 	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
 
 	lpi_write_config(d, clr, set);
-	its_send_inv(its_dev, its_get_event_id(d));
+	if (gic_rdists->has_direct_lpi && !irqd_is_forwarded_to_vcpu(d))
+		direct_lpi_inv(d);
+	else if (!irqd_is_forwarded_to_vcpu(d))
+		its_send_inv(its_dev, its_get_event_id(d));
+	else
+		its_send_vinv(its_dev, its_get_event_id(d));
 }
 
 static void its_vlpi_set_doorbell(struct irq_data *d, bool enable)
 {
 	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
 	u32 event = its_get_event_id(d);
+	struct its_vlpi_map *map;
 
-	if (its_dev->event_map.vlpi_maps[event].db_enabled == enable)
+	map = dev_event_to_vlpi_map(its_dev, event);
+
+	if (map->db_enabled == enable)
 		return;
 
-	its_dev->event_map.vlpi_maps[event].db_enabled = enable;
+	map->db_enabled = enable;
 
 	/*
 	 * More fun with the architecture:
@@ -1193,10 +1358,17 @@ static int its_irq_set_irqchip_state(struct irq_data *d,
 	if (which != IRQCHIP_STATE_PENDING)
 		return -EINVAL;
 
-	if (state)
-		its_send_int(its_dev, event);
-	else
-		its_send_clear(its_dev, event);
+	if (irqd_is_forwarded_to_vcpu(d)) {
+		if (state)
+			its_send_vint(its_dev, event);
+		else
+			its_send_vclear(its_dev, event);
+	} else {
+		if (state)
+			its_send_int(its_dev, event);
+		else
+			its_send_clear(its_dev, event);
+	}
 
 	return 0;
 }
@@ -1264,13 +1436,13 @@ static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info)
 	if (!info->map)
 		return -EINVAL;
 
-	mutex_lock(&its_dev->event_map.vlpi_lock);
+	raw_spin_lock(&its_dev->event_map.vlpi_lock);
 
 	if (!its_dev->event_map.vm) {
 		struct its_vlpi_map *maps;
 
 		maps = kcalloc(its_dev->event_map.nr_lpis, sizeof(*maps),
-			       GFP_KERNEL);
+			       GFP_ATOMIC);
 		if (!maps) {
 			ret = -ENOMEM;
 			goto out;
@@ -1313,29 +1485,30 @@ static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info)
 	}
 
 out:
-	mutex_unlock(&its_dev->event_map.vlpi_lock);
+	raw_spin_unlock(&its_dev->event_map.vlpi_lock);
 	return ret;
 }
 
 static int its_vlpi_get(struct irq_data *d, struct its_cmd_info *info)
 {
 	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
-	u32 event = its_get_event_id(d);
+	struct its_vlpi_map *map;
 	int ret = 0;
 
-	mutex_lock(&its_dev->event_map.vlpi_lock);
+	raw_spin_lock(&its_dev->event_map.vlpi_lock);
 
-	if (!its_dev->event_map.vm ||
-	    !its_dev->event_map.vlpi_maps[event].vm) {
+	map = get_vlpi_map(d);
+
+	if (!its_dev->event_map.vm || !map) {
 		ret = -EINVAL;
 		goto out;
 	}
 
 	/* Copy our mapping information to the incoming request */
-	*info->map = its_dev->event_map.vlpi_maps[event];
+	*info->map = *map;
 
 out:
-	mutex_unlock(&its_dev->event_map.vlpi_lock);
+	raw_spin_unlock(&its_dev->event_map.vlpi_lock);
 	return ret;
 }
 
@@ -1345,7 +1518,7 @@ static int its_vlpi_unmap(struct irq_data *d)
 	u32 event = its_get_event_id(d);
 	int ret = 0;
 
-	mutex_lock(&its_dev->event_map.vlpi_lock);
+	raw_spin_lock(&its_dev->event_map.vlpi_lock);
 
 	if (!its_dev->event_map.vm || !irqd_is_forwarded_to_vcpu(d)) {
 		ret = -EINVAL;
@@ -1375,7 +1548,7 @@ static int its_vlpi_unmap(struct irq_data *d)
 	}
 
 out:
-	mutex_unlock(&its_dev->event_map.vlpi_lock);
+	raw_spin_unlock(&its_dev->event_map.vlpi_lock);
 	return ret;
 }
 
@@ -1401,7 +1574,7 @@ static int its_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
 	struct its_cmd_info *info = vcpu_info;
 
 	/* Need a v4 ITS */
-	if (!its_dev->its->is_v4)
+	if (!is_v4(its_dev->its))
 		return -EINVAL;
 
 	/* Unmap request? */
@@ -1907,9 +2080,9 @@ static bool its_parse_indirect_baser(struct its_node *its,
 	if (new_order >= MAX_ORDER) {
 		new_order = MAX_ORDER - 1;
 		ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz);
-		pr_warn("ITS@%pa: %s Table too large, reduce ids %u->%u\n",
+		pr_warn("ITS@%pa: %s Table too large, reduce ids %llu->%u\n",
 			&its->phys_base, its_base_type_string[type],
-			its->device_ids, ids);
+			device_ids(its), ids);
 	}
 
 	*order = new_order;
@@ -1955,7 +2128,7 @@ static int its_alloc_tables(struct its_node *its)
 		case GITS_BASER_TYPE_DEVICE:
 			indirect = its_parse_indirect_baser(its, baser,
 							    psz, &order,
-							    its->device_ids);
+							    device_ids(its));
 			break;
 
 		case GITS_BASER_TYPE_VCPU:
@@ -2346,7 +2519,7 @@ static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
 
 	/* Don't allow device id that exceeds ITS hardware limit */
 	if (!baser)
-		return (ilog2(dev_id) < its->device_ids);
+		return (ilog2(dev_id) < device_ids(its));
 
 	return its_alloc_table_entry(its, baser, dev_id);
 }
@@ -2365,7 +2538,7 @@ static bool its_alloc_vpe_table(u32 vpe_id)
 	list_for_each_entry(its, &its_nodes, entry) {
 		struct its_baser *baser;
 
-		if (!its->is_v4)
+		if (!is_v4(its))
 			continue;
 
 		baser = its_get_baser(its, GITS_BASER_TYPE_VCPU);
@@ -2404,7 +2577,7 @@ static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
 	 * sized as a power of two (and you need at least one bit...).
 	 */
 	nr_ites = max(2, nvecs);
-	sz = nr_ites * its->ite_size;
+	sz = nr_ites * (FIELD_GET(GITS_TYPER_ITT_ENTRY_SIZE, its->typer) + 1);
 	sz = max(sz, ITS_ITT_ALIGN) + ITS_ITT_ALIGN - 1;
 	itt = kzalloc_node(sz, GFP_KERNEL, its->numa_node);
 	if (alloc_lpis) {
@@ -2435,7 +2608,7 @@ static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
 	dev->event_map.col_map = col_map;
 	dev->event_map.lpi_base = lpi_base;
 	dev->event_map.nr_lpis = nr_lpis;
-	mutex_init(&dev->event_map.vlpi_lock);
+	raw_spin_lock_init(&dev->event_map.vlpi_lock);
 	dev->device_id = dev_id;
 	INIT_LIST_HEAD(&dev->entry);
 
@@ -2456,6 +2629,7 @@ static void its_free_device(struct its_device *its_dev)
 	raw_spin_lock_irqsave(&its_dev->its->lock, flags);
 	list_del(&its_dev->entry);
 	raw_spin_unlock_irqrestore(&its_dev->its->lock, flags);
+	kfree(its_dev->event_map.col_map);
 	kfree(its_dev->itt);
 	kfree(its_dev);
 }
@@ -2664,7 +2838,6 @@ static void its_irq_domain_free(struct irq_domain *domain, unsigned int virq,
 		its_lpi_free(its_dev->event_map.lpi_map,
 			     its_dev->event_map.lpi_base,
 			     its_dev->event_map.nr_lpis);
-		kfree(its_dev->event_map.col_map);
 
 		/* Unmap device/itt */
 		its_send_mapd(its_dev, 0);
@@ -2757,8 +2930,7 @@ static void its_vpe_db_proxy_move(struct its_vpe *vpe, int from, int to)
 
 		rdbase = per_cpu_ptr(gic_rdists->rdist, from)->rd_base;
 		gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_CLRLPIR);
-		while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
-			cpu_relax();
+		wait_for_syncr(rdbase);
 
 		return;
 	}
@@ -2854,7 +3026,7 @@ static void its_vpe_invall(struct its_vpe *vpe)
 	struct its_node *its;
 
 	list_for_each_entry(its, &its_nodes, entry) {
-		if (!its->is_v4)
+		if (!is_v4(its))
 			continue;
 
 		if (its_list_map && !vpe->its_vm->vlpi_count[its->list_nr])
@@ -2912,10 +3084,10 @@ static void its_vpe_send_inv(struct irq_data *d)
 	if (gic_rdists->has_direct_lpi) {
 		void __iomem *rdbase;
 
+		/* Target the redistributor this VPE is currently known on */
 		rdbase = per_cpu_ptr(gic_rdists->rdist, vpe->col_idx)->rd_base;
-		gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_INVLPIR);
-		while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
-			cpu_relax();
+		gic_write_lpir(d->parent_data->hwirq, rdbase + GICR_INVLPIR);
+		wait_for_syncr(rdbase);
 	} else {
 		its_vpe_send_cmd(vpe, its_send_inv);
 	}
@@ -2957,8 +3129,7 @@ static int its_vpe_set_irqchip_state(struct irq_data *d,
 			gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_SETLPIR);
 		} else {
 			gic_write_lpir(vpe->vpe_db_lpi, rdbase + GICR_CLRLPIR);
-			while (gic_read_lpir(rdbase + GICR_SYNCR) & 1)
-				cpu_relax();
+			wait_for_syncr(rdbase);
 		}
 	} else {
 		if (state)
@@ -3123,7 +3294,7 @@ static int its_vpe_irq_domain_activate(struct irq_domain *domain,
 	vpe->col_idx = cpumask_first(cpu_online_mask);
 
 	list_for_each_entry(its, &its_nodes, entry) {
-		if (!its->is_v4)
+		if (!is_v4(its))
 			continue;
 
 		its_send_vmapp(its, vpe, true);
@@ -3149,7 +3320,7 @@ static void its_vpe_irq_domain_deactivate(struct irq_domain *domain,
 		return;
 
 	list_for_each_entry(its, &its_nodes, entry) {
-		if (!its->is_v4)
+		if (!is_v4(its))
 			continue;
 
 		its_send_vmapp(its, vpe, false);
@@ -3200,8 +3371,9 @@ static bool __maybe_unused its_enable_quirk_cavium_22375(void *data)
 {
 	struct its_node *its = data;
 
-	/* erratum 22375: only alloc 8MB table size */
-	its->device_ids = 0x14;		/* 20 bits, 8MB */
+	/* erratum 22375: only alloc 8MB table size (20 bits) */
+	its->typer &= ~GITS_TYPER_DEVBITS;
+	its->typer |= FIELD_PREP(GITS_TYPER_DEVBITS, 20 - 1);
 	its->flags |= ITS_FLAGS_WORKAROUND_CAVIUM_22375;
 
 	return true;
@@ -3221,7 +3393,8 @@ static bool __maybe_unused its_enable_quirk_qdf2400_e0065(void *data)
 	struct its_node *its = data;
 
 	/* On QDF2400, the size of the ITE is 16Bytes */
-	its->ite_size = 16;
+	its->typer &= ~GITS_TYPER_ITT_ENTRY_SIZE;
+	its->typer |= FIELD_PREP(GITS_TYPER_ITT_ENTRY_SIZE, 16 - 1);
 
 	return true;
 }
@@ -3255,8 +3428,10 @@ static bool __maybe_unused its_enable_quirk_socionext_synquacer(void *data)
 		its->get_msi_base = its_irq_get_msi_base_pre_its;
 
 		ids = ilog2(pre_its_window[1]) - 2;
-		if (its->device_ids > ids)
-			its->device_ids = ids;
+		if (device_ids(its) > ids) {
+			its->typer &= ~GITS_TYPER_DEVBITS;
+			its->typer |= FIELD_PREP(GITS_TYPER_DEVBITS, ids - 1);
+		}
 
 		/* the pre-ITS breaks isolation, so disable MSI remapping */
 		its->msi_domain_flags &= ~IRQ_DOMAIN_FLAG_MSI_REMAP;
@@ -3489,7 +3664,7 @@ static int its_init_vpe_domain(void)
 	}
 
 	/* Use the last possible DevID */
-	devid = GENMASK(its->device_ids - 1, 0);
+	devid = GENMASK(device_ids(its) - 1, 0);
 	vpe_proxy.dev = its_create_device(its, devid, entries, false);
 	if (!vpe_proxy.dev) {
 		kfree(vpe_proxy.vpes);
@@ -3587,12 +3762,10 @@ static int __init its_probe_one(struct resource *res,
 	INIT_LIST_HEAD(&its->entry);
 	INIT_LIST_HEAD(&its->its_device_list);
 	typer = gic_read_typer(its_base + GITS_TYPER);
+	its->typer = typer;
 	its->base = its_base;
 	its->phys_base = res->start;
-	its->ite_size = GITS_TYPER_ITT_ENTRY_SIZE(typer);
-	its->device_ids = GITS_TYPER_DEVBITS(typer);
-	its->is_v4 = !!(typer & GITS_TYPER_VLPIS);
-	if (its->is_v4) {
+	if (is_v4(its)) {
 		if (!(typer & GITS_TYPER_VMOVP)) {
 			err = its_compute_its_list_map(res, its_base);
 			if (err < 0)
@@ -3659,7 +3832,7 @@ static int __init its_probe_one(struct resource *res,
 	gits_write_cwriter(0, its->base + GITS_CWRITER);
 	ctlr = readl_relaxed(its->base + GITS_CTLR);
 	ctlr |= GITS_CTLR_ENABLE;
-	if (its->is_v4)
+	if (is_v4(its))
 		ctlr |= GITS_CTLR_ImDe;
 	writel_relaxed(ctlr, its->base + GITS_CTLR);
 
@@ -3984,7 +4157,7 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
 		return err;
 
 	list_for_each_entry(its, &its_nodes, entry)
-		has_v4 |= its->is_v4;
+		has_v4 |= is_v4(its);
 
 	if (has_v4 & rdists->has_vlpis) {
 		if (its_init_vpe_domain() ||