msm: msi: add support for Synopsys MSI

Propagate Synopsys MSI support from msm-4.14 for PCIe controller and PCIe MSI driver. Changes support: 1) QGIC MSI/MSI-X 2) Synopsys MSI/MSI-X 3) PCIe controller low power modes with MSI Change-Id: If7a2e1980233e032325ffec597284b9164162407 Signed-off-by: Tony Truong <truong@codeaurora.org>
2026-10-08 04:42:04 -04:00 · 2020-05-06 13:39:14 -07:00 · 2020-05-06 13:39:14 -07:00 · de69ee66f3
commit de69ee66f3
parent 9644a106b1
3 changed files with 381 additions and 68 deletions
--- a/drivers/pci/controller/pci-msm-msi.c
+++ b/drivers/pci/controller/pci-msm-msi.c
@ -7,28 +7,68 @@
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
 #include <linux/msi.h>
+#include <linux/msm_pcie.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/of_pci.h>
 #include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#define PCIE_MSI_CTRL_BASE (0x820)
+#define PCIE_MSI_CTRL_ADDR_OFFS (PCIE_MSI_CTRL_BASE)
+#define PCIE_MSI_CTRL_UPPER_ADDR_OFFS (PCIE_MSI_CTRL_BASE + 0x4)
+#define PCIE_MSI_CTRL_INT_N_EN_OFFS(n) (PCIE_MSI_CTRL_BASE + 0x8 + 0xc * (n))
+#define PCIE_MSI_CTRL_INT_N_MASK_OFFS(n) (PCIE_MSI_CTRL_BASE + 0xc + 0xc * (n))
+#define PCIE_MSI_CTRL_INT_N_STATUS_OFFS(n) \
+	(PCIE_MSI_CTRL_BASE + 0x10 + 0xc * (n))
+
+#define MSI_IRQ_PER_GRP (32)
+
+enum msi_type {
+	MSM_MSI_TYPE_QCOM,
+	MSM_MSI_TYPE_SNPS,
+};

 struct msm_msi_irq {
+	struct msm_msi_client *client;
+	struct msm_msi_grp *grp; /* group the irq belongs to */
+	u32 grp_index; /* index in the group */
 	unsigned int hwirq; /* MSI controller hwirq */
 	unsigned int virq; /* MSI controller virq */
+	u32 pos; /* position in MSI bitmap */
+};
+
+struct msm_msi_grp {
+	/* registers for SNPS only */
+	void __iomem *int_en_reg;
+	void __iomem *int_mask_reg;
+	void __iomem *int_status_reg;
+	u32 mask; /* tracks masked/unmasked MSI */
+
+	struct msm_msi_irq irqs[MSI_IRQ_PER_GRP];
 };

 struct msm_msi {
 	struct list_head clients;
 	struct device *dev;
 	struct device_node *of_node;
-	int nr_irqs;
-	struct msm_msi_irq *irqs;
+	int nr_hwirqs;
+	int nr_virqs;
+	int nr_grps;
+	struct msm_msi_grp *grps;
 	unsigned long *bitmap; /* tracks used/unused MSI */
 	struct mutex mutex; /* mutex for modifying MSI client list and bitmap */
 	struct irq_domain *inner_domain; /* parent domain; gen irq related */
 	struct irq_domain *msi_domain; /* child domain; pci related */
 	phys_addr_t msi_addr;
 	u32 msi_addr_size;
+	enum msi_type type;
+	spinlock_t cfg_lock; /* lock for configuring Synopsys MSI registers */
+	bool cfg_access; /* control access to MSI registers */
+	void __iomem *pcie_cfg;
+
+	void (*mask_irq)(struct irq_data *data);
+	void (*unmask_irq)(struct irq_data *data);
 };

 /* structure for each client of MSI controller */
@ -40,7 +80,35 @@ struct msm_msi_client {
 	dma_addr_t msi_addr;
 };

-static void msm_msi_handler(struct irq_desc *desc)
+static void msm_msi_snps_handler(struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct msm_msi_grp *msi_grp;
+	int i;
+	u32 status, mask;
+
+	chained_irq_enter(chip, desc);
+
+	msi_grp = irq_desc_get_handler_data(desc);
+
+	status = readl_relaxed(msi_grp->int_status_reg);
+
+	/* always update the mask set in msm_msi_snps_mask_irq */
+	mask = msi_grp->mask;
+	writel_relaxed(mask, msi_grp->int_mask_reg);
+
+	/* process only interrupts which are not masked */
+	status ^= (status & mask);
+	writel_relaxed(status, msi_grp->int_status_reg);
+
+	for (i = 0; status; i++, status >>= 1)
+		if (status & 0x1)
+			generic_handle_irq(msi_grp->irqs[i].virq);
+
+	chained_irq_exit(chip, desc);
+}
+
+static void msm_msi_qgic_handler(struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_desc_get_chip(desc);
 	struct msm_msi *msi;
@ -56,34 +124,98 @@ static void msm_msi_handler(struct irq_desc *desc)
 	chained_irq_exit(chip, desc);
 }

-static void msm_msi_mask_irq(struct irq_data *data)
+static void msm_msi_snps_mask_irq(struct irq_data *data)
+{
+	struct msm_msi_irq *msi_irq = irq_data_get_irq_chip_data(data);
+	struct msm_msi_grp *msi_grp = msi_irq->grp;
+	struct msm_msi *msi = msi_irq->client->msi;
+	unsigned long flags;
+
+	spin_lock_irqsave(&msi->cfg_lock, flags);
+	msi_grp->mask |= BIT(msi_irq->grp_index);
+	spin_unlock_irqrestore(&msi->cfg_lock, flags);
+}
+
+static void msm_msi_qgic_mask_irq(struct irq_data *data)
 {
 	struct irq_data *parent_data;

-	if (!data->parent_data)
-		return;
-
-	parent_data = irq_get_irq_data(data->parent_data->hwirq);
+	parent_data = irq_get_irq_data(irqd_to_hwirq(data));
 	if (!parent_data || !parent_data->chip)
 		return;

-	pci_msi_mask_irq(data);
 	parent_data->chip->irq_mask(parent_data);
 }

+static void msm_msi_mask_irq(struct irq_data *data)
+{
+	struct irq_data *parent_data;
+	struct msm_msi_irq *msi_irq;
+	struct msm_msi *msi;
+	unsigned long flags;
+
+	parent_data = data->parent_data;
+	if (!parent_data)
+		return;
+
+	msi_irq = irq_data_get_irq_chip_data(parent_data);
+	msi = msi_irq->client->msi;
+
+	spin_lock_irqsave(&msi->cfg_lock, flags);
+	if (msi->cfg_access)
+		pci_msi_mask_irq(data);
+	spin_unlock_irqrestore(&msi->cfg_lock, flags);
+
+	msi->mask_irq(parent_data);
+}
+
+static void msm_msi_snps_unmask_irq(struct irq_data *data)
+{
+	struct msm_msi_irq *msi_irq = irq_data_get_irq_chip_data(data);
+	struct msm_msi_grp *msi_grp = msi_irq->grp;
+	struct msm_msi *msi = msi_irq->client->msi;
+	unsigned long flags;
+
+	spin_lock_irqsave(&msi->cfg_lock, flags);
+
+	msi_grp->mask &= ~BIT(msi_irq->grp_index);
+	if (msi->cfg_access)
+		writel_relaxed(msi_grp->mask, msi_grp->int_mask_reg);
+
+	spin_unlock_irqrestore(&msi->cfg_lock, flags);
+}
+
+static void msm_msi_qgic_unmask_irq(struct irq_data *data)
+{
+	struct irq_data *parent_data;
+
+	parent_data = irq_get_irq_data(irqd_to_hwirq(data));
+	if (!parent_data || !parent_data->chip)
+		return;
+
+	parent_data->chip->irq_unmask(parent_data);
+}
+
 static void msm_msi_unmask_irq(struct irq_data *data)
 {
 	struct irq_data *parent_data;
+	struct msm_msi_irq *msi_irq;
+	struct msm_msi *msi;
+	unsigned long flags;

-	if (!data->parent_data)
+	parent_data = data->parent_data;
+	if (!parent_data)
 		return;

-	parent_data = irq_get_irq_data(data->parent_data->hwirq);
-	if (!parent_data || !parent_data->chip)
-		return;
+	msi_irq = irq_data_get_irq_chip_data(parent_data);
+	msi = msi_irq->client->msi;

-	parent_data->chip->irq_unmask(parent_data);
-	pci_msi_unmask_irq(data);
+	msi->unmask_irq(parent_data);
+
+	spin_lock_irqsave(&msi->cfg_lock, flags);
+	if (msi->cfg_access)
+		pci_msi_unmask_irq(data);
+	spin_unlock_irqrestore(&msi->cfg_lock, flags);
 }

 static struct irq_chip msm_msi_irq_chip = {
@ -106,12 +238,21 @@ static int msm_msi_domain_prepare(struct irq_domain *domain, struct device *dev,

 	client->msi = msi;
 	client->dev = dev;
-	client->msi_addr = dma_map_resource(client->dev, msi->msi_addr,
-				msi->msi_addr_size, DMA_FROM_DEVICE, 0);
-	if (dma_mapping_error(client->dev, client->msi_addr)) {
-		dev_err(msi->dev, "MSI: failed to map msi address\n");
-		client->msi_addr = 0;
-		return -ENOMEM;
+	client->msi_addr = msi->msi_addr;
+
+	/*
+	 * Accesses to QGIC MSI doorbell register goes through PCIe SMMU and
+	 * needs to be mapped. Synopsys MSI doorbell is within the PCIe core
+	 * and does not need to be mapped.
+	 */
+	if (msi->type == MSM_MSI_TYPE_QCOM) {
+		client->msi_addr = dma_map_resource(client->dev, msi->msi_addr,
+					msi->msi_addr_size, DMA_FROM_DEVICE, 0);
+		if (dma_mapping_error(client->dev, client->msi_addr)) {
+			dev_err(msi->dev, "MSI: failed to map msi address\n");
+			client->msi_addr = 0;
+			return -ENOMEM;
+		}
 	}

 	mutex_lock(&msi->mutex);
@ -147,7 +288,7 @@ static void msm_msi_domain_finish(msi_alloc_info_t *arg, int retval)
 		if (!client)
 			return;

-		if (client->msi_addr)
+		if ((msi->type == MSM_MSI_TYPE_QCOM) && client->msi_addr)
 			dma_unmap_resource(client->dev, client->msi_addr,
 					PAGE_SIZE, DMA_FROM_DEVICE, 0);

@ -188,8 +329,10 @@ static int msm_msi_irq_set_affinity(struct irq_data *data,
 static void msm_msi_irq_compose_msi_msg(struct irq_data *data,
 					  struct msi_msg *msg)
 {
-	struct msm_msi_client *client = irq_data_get_irq_chip_data(data);
+	struct msm_msi_irq *msi_irq = irq_data_get_irq_chip_data(data);
 	struct irq_data *parent_data = irq_get_irq_data(irqd_to_hwirq(data));
+	struct msm_msi_client *client = msi_irq->client;
+	struct msm_msi *msi = client->msi;

 	if (!parent_data)
 		return;
@ -197,8 +340,8 @@ static void msm_msi_irq_compose_msi_msg(struct irq_data *data,
 	msg->address_lo = lower_32_bits(client->msi_addr);
 	msg->address_hi = upper_32_bits(client->msi_addr);

-	/* GIC HW IRQ */
-	msg->data = irqd_to_hwirq(parent_data);
+	msg->data = (msi->type == MSM_MSI_TYPE_QCOM) ?
+			irqd_to_hwirq(parent_data) : msi_irq->pos;
 }

 static struct irq_chip msm_msi_bottom_irq_chip = {
@ -231,9 +374,9 @@ static int msm_msi_irq_domain_alloc(struct irq_domain *domain,
 		goto out;
 	}

-	pos = bitmap_find_next_zero_area(msi->bitmap, msi->nr_irqs, 0,
-					nr_irqs, 0);
-	if (pos < msi->nr_irqs) {
+	pos = bitmap_find_next_zero_area(msi->bitmap, msi->nr_virqs, 0,
+					nr_irqs, nr_irqs - 1);
+	if (pos < msi->nr_virqs) {
 		bitmap_set(msi->bitmap, pos, nr_irqs);
 	} else {
 		ret = -ENOSPC;
@ -241,10 +384,15 @@ static int msm_msi_irq_domain_alloc(struct irq_domain *domain,
 	}

 	for (i = 0; i < nr_irqs; i++) {
-		msi->irqs[pos].virq = virq + i;
-		irq_domain_set_info(domain, msi->irqs[pos].virq,
-				msi->irqs[pos].hwirq,
-				&msm_msi_bottom_irq_chip, client,
+		u32 grp = pos / MSI_IRQ_PER_GRP;
+		u32 index = pos % MSI_IRQ_PER_GRP;
+		struct msm_msi_irq *msi_irq = &msi->grps[grp].irqs[index];
+
+		msi_irq->virq = virq + i;
+		msi_irq->client = client;
+		irq_domain_set_info(domain, msi_irq->virq,
+				msi_irq->hwirq,
+				&msm_msi_bottom_irq_chip, msi_irq,
 				handle_simple_irq, NULL, NULL);
 		client->nr_irqs++;
 		pos++;
@ -259,27 +407,26 @@ static void msm_msi_irq_domain_free(struct irq_domain *domain,
 				      unsigned int virq, unsigned int nr_irqs)
 {
 	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
+	struct msm_msi_irq *msi_irq;
 	struct msm_msi_client *client;
 	struct msm_msi *msi;
-	int i;

 	if (!data)
 		return;

-	client = irq_data_get_irq_chip_data(data);
+	msi_irq = irq_data_get_irq_chip_data(data);
+	client  = msi_irq->client;
 	msi = client->msi;

 	mutex_lock(&msi->mutex);
-	for (i = 0; i < nr_irqs; i++)
-		if (msi->irqs[i].virq == virq)
-			break;

-	bitmap_clear(msi->bitmap, i, nr_irqs);
+	bitmap_clear(msi->bitmap, msi_irq->pos, nr_irqs);
 	client->nr_irqs -= nr_irqs;

 	if (!client->nr_irqs) {
-		dma_unmap_resource(client->dev, client->msi_addr, PAGE_SIZE,
-				DMA_FROM_DEVICE, 0);
+		if (msi->type == MSM_MSI_TYPE_QCOM)
+			dma_unmap_resource(client->dev, client->msi_addr,
+					PAGE_SIZE, DMA_FROM_DEVICE, 0);
 		list_del(&client->node);
 		devm_kfree(msi->dev, client);
 	}
@ -296,7 +443,7 @@ static const struct irq_domain_ops msi_domain_ops = {

 static int msm_msi_alloc_domains(struct msm_msi *msi)
 {
-	msi->inner_domain = irq_domain_add_linear(NULL, msi->nr_irqs,
+	msi->inner_domain = irq_domain_add_linear(NULL, msi->nr_virqs,
 						  &msi_domain_ops, msi);
 	if (!msi->inner_domain) {
 		dev_err(msi->dev, "MSI: failed to create IRQ domain\n");
@ -316,14 +463,152 @@ static int msm_msi_alloc_domains(struct msm_msi *msi)
 	return 0;
 }

-int msm_msi_init(struct device *dev)
+static int msm_msi_snps_irq_setup(struct msm_msi *msi)
+{
+	int i, index, ret;
+	struct msm_msi_grp *msi_grp;
+	struct msm_msi_irq *msi_irq;
+	unsigned int irq = 0;
+
+	/* setup each MSI group. nr_hwirqs == nr_grps */
+	for (i = 0; i < msi->nr_hwirqs; i++) {
+		irq = irq_of_parse_and_map(msi->of_node, i);
+		if (!irq) {
+			dev_err(msi->dev,
+				"MSI: failed to parse/map interrupt\n");
+			ret = -ENODEV;
+			goto free_irqs;
+		}
+
+		msi_grp = &msi->grps[i];
+		msi_grp->int_en_reg = msi->pcie_cfg +
+				PCIE_MSI_CTRL_INT_N_EN_OFFS(i);
+		msi_grp->int_mask_reg = msi->pcie_cfg +
+				PCIE_MSI_CTRL_INT_N_MASK_OFFS(i);
+		msi_grp->int_status_reg = msi->pcie_cfg +
+				PCIE_MSI_CTRL_INT_N_STATUS_OFFS(i);
+
+		for (index = 0; index < MSI_IRQ_PER_GRP; index++) {
+			msi_irq = &msi_grp->irqs[index];
+
+			msi_irq->grp = msi_grp;
+			msi_irq->grp_index = index;
+			msi_irq->pos = (i * MSI_IRQ_PER_GRP) + index;
+			msi_irq->hwirq = irq;
+		}
+
+		irq_set_chained_handler_and_data(irq, msm_msi_snps_handler,
+						msi_grp);
+	}
+
+	return 0;
+
+free_irqs:
+	for (--i; i >= 0; i--) {
+		irq = msi->grps[i].irqs[0].hwirq;
+
+		irq_set_chained_handler_and_data(irq, NULL, NULL);
+		irq_dispose_mapping(irq);
+	}
+
+	return ret;
+}
+
+static int msm_msi_qgic_irq_setup(struct msm_msi *msi)
 {
 	int i, ret;
+	u32 index, grp;
+	struct msm_msi_grp *msi_grp;
+	struct msm_msi_irq *msi_irq;
+	unsigned int irq = 0;
+
+	for (i = 0; i < msi->nr_hwirqs; i++) {
+		irq = irq_of_parse_and_map(msi->of_node, i);
+		if (!irq) {
+			dev_err(msi->dev,
+				"MSI: failed to parse/map interrupt\n");
+			ret = -ENODEV;
+			goto free_irqs;
+		}
+
+		grp = i / MSI_IRQ_PER_GRP;
+		index = i % MSI_IRQ_PER_GRP;
+		msi_grp = &msi->grps[grp];
+		msi_irq = &msi_grp->irqs[index];
+
+		msi_irq->grp = msi_grp;
+		msi_irq->grp_index = index;
+		msi_irq->pos = i;
+		msi_irq->hwirq = irq;
+
+		irq_set_chained_handler_and_data(irq, msm_msi_qgic_handler,
+						msi);
+	}
+
+	return 0;
+
+free_irqs:
+	for (--i; i >= 0; i--) {
+		grp = i / MSI_IRQ_PER_GRP;
+		index = i % MSI_IRQ_PER_GRP;
+		irq = msi->grps[grp].irqs[index].hwirq;
+
+		irq_set_chained_handler_and_data(irq, NULL, NULL);
+		irq_dispose_mapping(irq);
+	}
+
+	return ret;
+}
+
+/* control access to PCIe MSI registers */
+void msm_msi_config_access(struct irq_domain *domain, bool allow)
+{
+	struct msm_msi *msi = domain->parent->host_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&msi->cfg_lock, flags);
+	msi->cfg_access = allow;
+	spin_unlock_irqrestore(&msi->cfg_lock, flags);
+}
+EXPORT_SYMBOL(msm_msi_config_access);
+
+void msm_msi_config(struct irq_domain *domain)
+{
+	struct msm_msi *msi;
+	int i;
+
+	msi = domain->parent->host_data;
+
+	/* PCIe core driver sets to false during LPM */
+	msm_msi_config_access(domain, true);
+
+	if (msi->type == MSM_MSI_TYPE_QCOM)
+		return;
+
+	/* program Synopsys MSI termination address */
+	writel_relaxed(msi->msi_addr, msi->pcie_cfg + PCIE_MSI_CTRL_ADDR_OFFS);
+	writel_relaxed(0, msi->pcie_cfg + PCIE_MSI_CTRL_UPPER_ADDR_OFFS);
+
+	/* restore mask and enable all interrupts for each group */
+	for (i = 0; i < msi->nr_grps; i++) {
+		struct msm_msi_grp *msi_grp = &msi->grps[i];
+
+		writel_relaxed(msi_grp->mask, msi_grp->int_mask_reg);
+		writel_relaxed(~0, msi_grp->int_en_reg);
+	}
+}
+EXPORT_SYMBOL(msm_msi_config);
+
+int msm_msi_init(struct device *dev)
+{
+	int ret;
 	struct msm_msi *msi;
 	struct device_node *of_node;
 	const __be32 *prop_val;
 	struct of_phandle_args irq;
 	u32 size_exp = 0;
+	struct resource *res;
+	int (*msi_irq_setup)(struct msm_msi *msi);

 	if (!dev->of_node) {
 		dev_err(dev, "MSI: missing DT node\n");
@ -356,6 +641,7 @@ int msm_msi_init(struct device *dev)
 	msi->dev = dev;
 	msi->of_node = of_node;
 	mutex_init(&msi->mutex);
+	spin_lock_init(&msi->cfg_lock);
 	INIT_LIST_HEAD(&msi->clients);

 	prop_val = of_get_address(msi->of_node, 0, NULL, NULL);
@ -378,23 +664,58 @@ int msm_msi_init(struct device *dev)

 	msi->msi_addr_size = 1 << size_exp;

-	while (of_irq_parse_one(msi->of_node, msi->nr_irqs, &irq) == 0)
-		msi->nr_irqs++;
+	msi->type = of_property_read_bool(msi->of_node, "qcom,snps") ?
+			MSM_MSI_TYPE_SNPS : MSM_MSI_TYPE_QCOM;
+	dev_info(msi->dev, "MSI: %s controller is present\n",
+		msi->type == MSM_MSI_TYPE_SNPS ? "synopsys" : "qgic");

-	if (!msi->nr_irqs) {
+	while (of_irq_parse_one(msi->of_node, msi->nr_hwirqs, &irq) == 0)
+		msi->nr_hwirqs++;
+
+	if (!msi->nr_hwirqs) {
 		dev_err(msi->dev, "MSI: found no MSI interrupts\n");
 		ret = -ENODEV;
 		goto err;
 	}

-	msi->irqs = devm_kcalloc(msi->dev, msi->nr_irqs,
-				sizeof(*msi->irqs), GFP_KERNEL);
-	if (!msi->irqs) {
+	if (msi->type == MSM_MSI_TYPE_SNPS) {
+		res = platform_get_resource_byname(to_platform_device(dev),
+						IORESOURCE_MEM, "dm_core");
+		if (!res) {
+			dev_err(msi->dev,
+				"MSI: failed to get PCIe register base\n");
+			ret = -ENODEV;
+			goto err;
+		}
+
+		msi->pcie_cfg = devm_ioremap(msi->dev, res->start,
+						resource_size(res));
+		if (!msi->pcie_cfg) {
+			ret = -ENOMEM;
+			goto err;
+		}
+
+		msi->nr_virqs = msi->nr_hwirqs * MSI_IRQ_PER_GRP;
+		msi->nr_grps = msi->nr_hwirqs;
+		msi->mask_irq = msm_msi_snps_mask_irq;
+		msi->unmask_irq = msm_msi_snps_unmask_irq;
+		msi_irq_setup = msm_msi_snps_irq_setup;
+	} else {
+		msi->nr_virqs = msi->nr_hwirqs;
+		msi->nr_grps = 1;
+		msi->mask_irq = msm_msi_qgic_mask_irq;
+		msi->unmask_irq = msm_msi_qgic_unmask_irq;
+		msi_irq_setup = msm_msi_qgic_irq_setup;
+	}
+
+	msi->grps = devm_kcalloc(msi->dev, msi->nr_grps,
+				sizeof(*msi->grps), GFP_KERNEL);
+	if (!msi->grps) {
 		ret = -ENOMEM;
 		goto err;
 	}

-	msi->bitmap = devm_kcalloc(msi->dev, BITS_TO_LONGS(msi->nr_irqs),
+	msi->bitmap = devm_kcalloc(msi->dev, BITS_TO_LONGS(msi->nr_virqs),
 				   sizeof(*msi->bitmap), GFP_KERNEL);
 	if (!msi->bitmap) {
 		ret = -ENOMEM;
@ -407,30 +728,15 @@ int msm_msi_init(struct device *dev)
 		goto err;
 	}

-	for (i = 0; i < msi->nr_irqs; i++) {
-		unsigned int irq = irq_of_parse_and_map(msi->of_node, i);
+	ret = msi_irq_setup(msi);
+	if (ret)
+		goto remove_domains;

-		if (!irq) {
-			dev_err(msi->dev,
-				"MSI: failed to parse/map interrupt\n");
-			ret = -ENODEV;
-			goto free_irqs;
-		}
-
-		msi->irqs[i].hwirq = irq;
-		irq_set_chained_handler_and_data(msi->irqs[i].hwirq,
-						msm_msi_handler, msi);
-	}
+	msm_msi_config(msi->msi_domain);

 	return 0;

-free_irqs:
-	for (--i; i >= 0; i--) {
-		irq_set_chained_handler_and_data(msi->irqs[i].hwirq,
-						NULL, NULL);
-		irq_dispose_mapping(msi->irqs[i].hwirq);
-	}
-
+remove_domains:
 	irq_domain_remove(msi->msi_domain);
 	irq_domain_remove(msi->inner_domain);
 err:
--- a/drivers/pci/controller/pci-msm.c
+++ b/drivers/pci/controller/pci-msm.c
@ -3876,8 +3876,10 @@ static int msm_pcie_enable(struct msm_pcie_dev_t *dev)
 		goto link_fail;
 	}

-	if (dev->enumerated)
+	if (dev->enumerated) {
+		msm_msi_config(dev_get_msi_domain(&dev->dev->dev));
 		msm_pcie_config_link_pm(dev, true);
+	}

 	goto out;

@ -3918,6 +3920,9 @@ static void msm_pcie_disable(struct msm_pcie_dev_t *dev)
 		return;
 	}

+	/* suspend access to MSI register. resume access in msm_msi_config */
+	msm_msi_config_access(dev_get_msi_domain(&dev->dev->dev), false);
+
 	dev->link_status = MSM_PCIE_LINK_DISABLED;
 	dev->power_on = false;
 	dev->link_turned_off_counter++;
--- a/include/linux/msm_pcie.h
+++ b/include/linux/msm_pcie.h
@ -55,6 +55,8 @@ struct msm_pcie_register_event {
 	u32 options;
 };

+void msm_msi_config_access(struct irq_domain *domain, bool allow);
+void msm_msi_config(struct irq_domain *domain);
 int msm_msi_init(struct device *dev);

 #if IS_ENABLED(CONFIG_PCI_MSM)