[PATCH v12 13/25] genirq/msi: Provide MSI_FLAG_PARENT_PM_DEV

From: Anup Patel
Date: Sat Jan 27 2024 - 11:22:31 EST


From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Some platform-MSI implementations require that power management is
redirected to the underlying interrupt chip device. To make this work
with per device MSI domains provide a new feature flag and let the
core code handle the setup of dev->pm_dev when set during device MSI
domain creation.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
---
include/linux/msi.h | 2 ++
kernel/irq/msi.c | 5 ++++-
2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/linux/msi.h b/include/linux/msi.h
index ac73f678da7d..b21581ca8e9a 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -554,6 +554,8 @@ enum {
MSI_FLAG_FREE_MSI_DESCS = (1 << 6),
/* Use dev->fwnode for MSI device domain creation */
MSI_FLAG_USE_DEV_FWNODE = (1 << 7),
+ /* Set parent->dev into domain->pm_dev on device domain creation */
+ MSI_FLAG_PARENT_PM_DEV = (1 << 8),

/* Mask for the generic functionality */
MSI_GENERIC_FLAGS_MASK = GENMASK(15, 0),
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 07e9daaf0657..f90952ebc494 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -845,8 +845,11 @@ static struct irq_domain *__msi_create_irq_domain(struct fwnode_handle *fwnode,
domain = irq_domain_create_hierarchy(parent, flags | IRQ_DOMAIN_FLAG_MSI, 0,
fwnode, &msi_domain_ops, info);

- if (domain)
+ if (domain) {
irq_domain_update_bus_token(domain, info->bus_token);
+ if (info->flags & MSI_FLAG_PARENT_PM_DEV)
+ domain->pm_dev = parent->pm_dev;
+ }

return domain;
}
--
2.34.1