irqchip/irq-msi-lib: Optionally set default irq_eoi()/irq_ack()

msi_lib_init_dev_msi_info() sets the default irq_eoi()/irq_ack() callbacks
unconditionally. This is correct for all existing users, but prevents the
IMSIC driver to be moved to the MSI library implementation.

Introduce chip_flags in struct msi_parent_ops, which instruct the library
to selectively set the callbacks depending on the flags, and update all
current users to set them.

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Anup Patel <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/[email protected]

Author: KAGA-KOKO

drivers/irqchip/irq-gic-v2m.c

@@ -255,6 +255,7 @@ static void __init gicv2m_teardown(void)
 static struct msi_parent_ops gicv2m_msi_parent_ops = {
 	.supported_flags	= GICV2M_MSI_FLAGS_SUPPORTED,
 	.required_flags		= GICV2M_MSI_FLAGS_REQUIRED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_token	= DOMAIN_BUS_NEXUS,
 	.bus_select_mask	= MATCH_PCI_MSI | MATCH_PLATFORM_MSI,
 	.prefix			= "GICv2m-",

drivers/irqchip/irq-gic-v3-its-msi-parent.c

@@ -203,6 +203,7 @@ static bool its_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
 const struct msi_parent_ops gic_v3_its_msi_parent_ops = {
 	.supported_flags	= ITS_MSI_FLAGS_SUPPORTED,
 	.required_flags		= ITS_MSI_FLAGS_REQUIRED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_token	= DOMAIN_BUS_NEXUS,
 	.bus_select_mask	= MATCH_PCI_MSI | MATCH_PLATFORM_MSI,
 	.prefix			= "ITS-",

drivers/irqchip/irq-gic-v3-mbi.c

@@ -201,6 +201,7 @@ static bool mbi_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
 static const struct msi_parent_ops gic_v3_mbi_msi_parent_ops = {
 	.supported_flags	= MBI_MSI_FLAGS_SUPPORTED,
 	.required_flags		= MBI_MSI_FLAGS_REQUIRED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_token	= DOMAIN_BUS_NEXUS,
 	.bus_select_mask	= MATCH_PCI_MSI | MATCH_PLATFORM_MSI,
 	.prefix			= "MBI-",

drivers/irqchip/irq-imx-mu-msi.c

@@ -214,6 +214,7 @@ static void imx_mu_msi_irq_handler(struct irq_desc *desc)
 static const struct msi_parent_ops imx_mu_msi_parent_ops = {
 	.supported_flags	= IMX_MU_MSI_FLAGS_SUPPORTED,
 	.required_flags		= IMX_MU_MSI_FLAGS_REQUIRED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_token       = DOMAIN_BUS_NEXUS,
 	.bus_select_mask	= MATCH_PLATFORM_MSI,
 	.prefix			= "MU-MSI-",

drivers/irqchip/irq-loongson-pch-msi.c

@@ -146,6 +146,7 @@ static const struct irq_domain_ops pch_msi_middle_domain_ops = {
 static struct msi_parent_ops pch_msi_parent_ops = {
 	.required_flags		= PCH_MSI_FLAGS_REQUIRED,
 	.supported_flags	= PCH_MSI_FLAGS_SUPPORTED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_mask	= MATCH_PCI_MSI,
 	.bus_select_token	= DOMAIN_BUS_NEXUS,
 	.prefix			= "PCH-",

drivers/irqchip/irq-msi-lib.c

@@ -28,6 +28,7 @@ bool msi_lib_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
 			       struct msi_domain_info *info)
 {
 	const struct msi_parent_ops *pops = real_parent->msi_parent_ops;
+	struct irq_chip *chip = info->chip;
 	u32 required_flags;
 
 	/* Parent ops available? */
@@ -92,10 +93,10 @@ bool msi_lib_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
 	info->flags			|= required_flags;
 
 	/* Chip updates for all child bus types */
-	if (!info->chip->irq_eoi)
-		info->chip->irq_eoi	= irq_chip_eoi_parent;
-	if (!info->chip->irq_ack)
-		info->chip->irq_ack	= irq_chip_ack_parent;
+	if (!chip->irq_eoi && (pops->chip_flags & MSI_CHIP_FLAG_SET_EOI))
+		chip->irq_eoi = irq_chip_eoi_parent;
+	if (!chip->irq_ack && (pops->chip_flags & MSI_CHIP_FLAG_SET_ACK))
+		chip->irq_ack = irq_chip_ack_parent;
 
 	/*
 	 * The device MSI domain can never have a set affinity callback. It
@@ -105,7 +106,7 @@ bool msi_lib_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
 	 * device MSI domain aside of mask/unmask which is provided e.g. by
 	 * PCI/MSI device domains.
 	 */
-	info->chip->irq_set_affinity	= msi_domain_set_affinity;
+	chip->irq_set_affinity = msi_domain_set_affinity;
 	return true;
 }
 EXPORT_SYMBOL_GPL(msi_lib_init_dev_msi_info);

drivers/irqchip/irq-mvebu-gicp.c

@@ -161,6 +161,7 @@ static const struct irq_domain_ops gicp_domain_ops = {
 static const struct msi_parent_ops gicp_msi_parent_ops = {
 	.supported_flags	= GICP_MSI_FLAGS_SUPPORTED,
 	.required_flags		= GICP_MSI_FLAGS_REQUIRED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_token       = DOMAIN_BUS_GENERIC_MSI,
 	.bus_select_mask	= MATCH_PLATFORM_MSI,
 	.prefix			= "GICP-",

drivers/irqchip/irq-mvebu-odmi.c

@@ -157,6 +157,7 @@ static const struct irq_domain_ops odmi_domain_ops = {
 static const struct msi_parent_ops odmi_msi_parent_ops = {
 	.supported_flags	= ODMI_MSI_FLAGS_SUPPORTED,
 	.required_flags		= ODMI_MSI_FLAGS_REQUIRED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_token	= DOMAIN_BUS_GENERIC_MSI,
 	.bus_select_mask	= MATCH_PLATFORM_MSI,
 	.prefix			= "ODMI-",

drivers/irqchip/irq-mvebu-sei.c

@@ -356,6 +356,7 @@ static void mvebu_sei_reset(struct mvebu_sei *sei)
 static const struct msi_parent_ops sei_msi_parent_ops = {
 	.supported_flags	= SEI_MSI_FLAGS_SUPPORTED,
 	.required_flags		= SEI_MSI_FLAGS_REQUIRED,
+	.chip_flags		= MSI_CHIP_FLAG_SET_EOI | MSI_CHIP_FLAG_SET_ACK,
 	.bus_select_mask	= MATCH_PLATFORM_MSI,
 	.bus_select_token	= DOMAIN_BUS_GENERIC_MSI,
 	.prefix			= "SEI-",

include/linux/msi.h

@@ -558,11 +558,21 @@ enum {
 	MSI_FLAG_NO_AFFINITY		= (1 << 21),
 };
 
+/*
+ * Flags for msi_parent_ops::chip_flags
+ */
+enum {
+	MSI_CHIP_FLAG_SET_EOI		= (1 << 0),
+	MSI_CHIP_FLAG_SET_ACK		= (1 << 1),
+};
+
 /**
  * struct msi_parent_ops - MSI parent domain callbacks and configuration info
  *
  * @supported_flags:	Required: The supported MSI flags of the parent domain
  * @required_flags:	Optional: The required MSI flags of the parent MSI domain
+ * @chip_flags:		Optional: Select MSI chip callbacks to update with defaults
+ *			in msi_lib_init_dev_msi_info().
  * @bus_select_token:	Optional: The bus token of the real parent domain for
  *			irq_domain::select()
  * @bus_select_mask:	Optional: A mask of supported BUS_DOMAINs for
@@ -575,6 +585,7 @@ enum {
 struct msi_parent_ops {
 	u32		supported_flags;
 	u32		required_flags;
+	u32		chip_flags;
 	u32		bus_select_token;
 	u32		bus_select_mask;
 	const char	*prefix;