Re: [PATCH v2 5/6] drivers/hv/vmbus: Get the irq number from DeviceTree

[Roman Kisel]

On 5/15/2024 2:42 AM, Saurabh Singh Sengar wrote:
> On Tue, May 14, 2024 at 03:43:52PM -0700, Roman Kisel wrote:
> > The vmbus driver uses ACPI for interrupt assignment on
>
> In subject use the prefix "Drivers: hv: vmbus:".
> It is preferred to us "VMbus/VMBus" instead of "vmbus" for all the
> commit message and comments.
I can see "Drivers: hv: vmbus:" as a convention from the data[1], will 
update the commit message per that.

The recent Michael Kelly's patchset where the Hyper-V documentation is 
updated to use "VMBus" instead of the incorrect one (iiuc) "VMbus" 
compels me to use "VMBus" out of the options you have enumerated, in the 
commit description.

[1]
The data mining device was

git log --all --grep='Drivers: hv: vmbus:'

and variations thereof.

> > arm64 hence it won't function in the VTL mode where only
> > DeviceTree can be used.
> >
> > Update the vmbus driver to discover interrupt configuration
> > via DeviceTree.
> >
> > Signed-off-by: Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/hv/vmbus_drv.c | 37 +++++++++++++++++++++++++++++++++++++
> >   1 file changed, 37 insertions(+)
> >
> > diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> > index e25223cee3ab..52f01bd1c947 100644
> > --- a/drivers/hv/vmbus_drv.c
> > +++ b/drivers/hv/vmbus_drv.c
> > @@ -36,6 +36,7 @@
> >   #include <linux/syscore_ops.h>
> >   #include <linux/dma-map-ops.h>
> >   #include <linux/pci.h>
> > +#include <linux/of_irq.h>
> >   #include <clocksource/hyperv_timer.h>
> >   #include <asm/mshyperv.h>
> >   #include "hyperv_vmbus.h"
> > @@ -2316,6 +2317,34 @@ static int vmbus_acpi_add(struct platform_device *pdev)
> >   }
> >   #endif
> >   
> > +static int __maybe_unused vmbus_of_set_irq(struct device_node *np)
> > +{
> > +	struct irq_desc *desc;
> > +	int irq;
> > +
> > +	irq = of_irq_get(np, 0);
> > +	if (irq == 0) {
> > +		pr_err("VMBus interrupt mapping failure\n");
> > +		return -EINVAL;
> > +	}
> > +	if (irq < 0) {
> > +		pr_err("VMBus interrupt data can't be read from DeviceTree, error %d\n", irq);
> > +		return irq;
> > +	}
> > +
> > +	desc = irq_to_desc(irq);
> > +	if (!desc) {
> > +		pr_err("VMBus interrupt description can't be found for virq %d\n", irq);
> > +		return -ENODEV;
> > +	}
> > +
> > +	vmbus_irq = irq;
> > +	vmbus_interrupt = desc->irq_data.hwirq;
> > +	pr_debug("VMBus virq %d, hwirq %d\n", vmbus_irq, vmbus_interrupt);
> > +
> > +	return 0;
> > +}
> > +
> >   static int vmbus_device_add(struct platform_device *pdev)
> >   {
> >   	struct resource **cur_res = &hyperv_mmio;
> > @@ -2324,12 +2353,20 @@ static int vmbus_device_add(struct platform_device *pdev)
> >   	struct device_node *np = pdev->dev.of_node;
> >   	int ret;
> >   
> > +	pr_debug("VMBus is present in DeviceTree\n");
> > +
> >   	hv_dev = &pdev->dev;
> >   
> >   	ret = of_range_parser_init(&parser, np);
> >   	if (ret)
> >   		return ret;
> >   
> > +#ifndef HYPERVISOR_CALLBACK_VECTOR
> > +	ret = vmbus_of_set_irq(np);
> > +	if (ret)
> > +		return ret;
> > +#endif
> > +
> >   	for_each_of_range(&parser, &range) {
> >   		struct resource *res;
> >   
> > --
> > 2.45.0

--
Thank you,
Roman