Re: [PATCH v3 1/6] PCI: dwc: Add msi_host_isr() callback

From: Marc Zyngier
Date: Wed Jun 03 2020 - 07:15:08 EST


On 2020-06-03 09:54, Kunihiko Hayashi wrote:
This adds msi_host_isr() callback function support to describe
SoC-dependent service triggered by MSI.

For example, when AER interrupt is triggered by MSI, the callback function
reads SoC-dependent registers and detects that the interrupt is from AER,
and invoke AER interrupts related to MSI.

Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Jingoo Han <jingoohan1@xxxxxxxxx>
Cc: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-designware-host.c | 8 ++++----
drivers/pci/controller/dwc/pcie-designware.h | 1 +
2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c
b/drivers/pci/controller/dwc/pcie-designware-host.c
index 0a4a5aa..9b628a2 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -112,13 +112,13 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp)
static void dw_chained_msi_isr(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
- struct pcie_port *pp;
+ struct pcie_port *pp = irq_desc_get_handler_data(desc);

- chained_irq_enter(chip, desc);
+ if (pp->ops->msi_host_isr)
+ pp->ops->msi_host_isr(pp);

Why is this call outside of the enter/exit guards?
Do you still need to execute the standard handler?


- pp = irq_desc_get_handler_data(desc);
+ chained_irq_enter(chip, desc);
dw_handle_msi_irq(pp);
-
chained_irq_exit(chip, desc);
}

diff --git a/drivers/pci/controller/dwc/pcie-designware.h
b/drivers/pci/controller/dwc/pcie-designware.h
index 656e00f..e741967 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -170,6 +170,7 @@ struct dw_pcie_host_ops {
void (*scan_bus)(struct pcie_port *pp);
void (*set_num_vectors)(struct pcie_port *pp);
int (*msi_host_init)(struct pcie_port *pp);
+ void (*msi_host_isr)(struct pcie_port *pp);
};

struct pcie_port {

Thanks,

M.
--
Jazz is not dead. It just smells funny...