On Fri, Jul 26, 2024 at 03:59:10PM -0700, Roman Kisel wrote:
> The hyperv-pci driver uses ACPI for MSI IRQ domain configuration on
> arm64. It won't be able to do that in the VTL mode where only DeviceTree
> can be used.
>
> Update the hyperv-pci driver to get vPCI MSI IRQ domain in the DeviceTree
> case, too.
>
> Signed-off-by: Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/hv/vmbus_drv.c | 23 +++++++-----
> drivers/pci/controller/pci-hyperv.c | 55 +++++++++++++++++++++++++++--
> include/linux/hyperv.h | 2 ++
> 3 files changed, 69 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index 7eee7caff5f6..038bd9be64b7 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -45,7 +45,8 @@ struct vmbus_dynid {
> struct hv_vmbus_device_id id;
> };
>
> -static struct device *hv_dev;
> +/* VMBus Root Device */
> +static struct device *vmbus_root_device;
You're changing the name of the variable. That should preferably be done
in a separate patch. That's going to make this patch shorter and easier
to review.
>
> static int hyperv_cpuhp_online;
>
> @@ -80,9 +81,15 @@ static struct resource *fb_mmio;
> static struct resource *hyperv_mmio;
> static DEFINE_MUTEX(hyperv_mmio_lock);
>
> +struct device *get_vmbus_root_device(void)
> +{
> + return vmbus_root_device;
> +}
> +EXPORT_SYMBOL_GPL(get_vmbus_root_device);
I would like you to add "hv_" prefix to this exported symbol, or rename
it to "vmbus_get_root_device()".
> +
> static int vmbus_exists(void)
> {
> - if (hv_dev == NULL)
> + if (vmbus_root_device == NULL)
> return -ENODEV;
>
> return 0;
> @@ -861,7 +868,7 @@ static int vmbus_dma_configure(struct device *child_device)
> * On x86/x64 coherence is assumed and these calls have no effect.
> */
> hv_setup_dma_ops(child_device,
> - device_get_dma_attr(hv_dev) == DEV_DMA_COHERENT);
> + device_get_dma_attr(vmbus_root_device) == DEV_DMA_COHERENT);
> return 0;
> }
>
> @@ -1892,7 +1899,7 @@ int vmbus_device_register(struct hv_device *child_device_obj)
> &child_device_obj->channel->offermsg.offer.if_instance);
>
> child_device_obj->device.bus = &hv_bus;
> - child_device_obj->device.parent = hv_dev;
> + child_device_obj->device.parent = vmbus_root_device;
> child_device_obj->device.release = vmbus_device_release;
>
> child_device_obj->device.dma_parms = &child_device_obj->dma_parms;
> @@ -2253,7 +2260,7 @@ static int vmbus_acpi_add(struct platform_device *pdev)
> struct acpi_device *ancestor;
> struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
>
> - hv_dev = &device->dev;
> + vmbus_root_device = &device->dev;
>
> /*
> * Older versions of Hyper-V for ARM64 fail to include the _CCA
> @@ -2342,7 +2349,7 @@ static int vmbus_device_add(struct platform_device *pdev)
> struct device_node *np = pdev->dev.of_node;
> int ret;
>
> - hv_dev = &pdev->dev;
> + vmbus_root_device = &pdev->dev;
>
> ret = of_range_parser_init(&parser, np);
> if (ret)
> @@ -2675,7 +2682,7 @@ static int __init hv_acpi_init(void)
> if (ret)
> return ret;
>
> - if (!hv_dev) {
> + if (!vmbus_root_device) {
> ret = -ENODEV;
> goto cleanup;
> }
> @@ -2706,7 +2713,7 @@ static int __init hv_acpi_init(void)
>
> cleanup:
> platform_driver_unregister(&vmbus_platform_driver);
> - hv_dev = NULL;
> + vmbus_root_device = NULL;
> return ret;
> }
>
> diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
> index 5992280e8110..cdecefd1f9bd 100644
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -50,6 +50,7 @@
> #include <linux/irqdomain.h>
> #include <linux/acpi.h>
> #include <linux/sizes.h>
> +#include <linux/of_irq.h>
> #include <asm/mshyperv.h>
>
> /*
> @@ -887,6 +888,35 @@ static const struct irq_domain_ops hv_pci_domain_ops = {
> .activate = hv_pci_vec_irq_domain_activate,
> };
>
> +#ifdef CONFIG_OF
> +
> +static struct irq_domain *hv_pci_of_irq_domain_parent(void)
> +{
> + struct device_node *parent;
> + struct irq_domain *domain;
> +
> + parent = of_irq_find_parent(to_platform_device(get_vmbus_root_device())->dev.of_node);
> + domain = NULL;
> + if (parent) {
> + domain = irq_find_host(parent);
> + of_node_put(parent);
> + }
> +
I cannot really comment on the ARM side of things around how this system
is set up. I will leave that to someone who's more familiar with the
matter to review.
Thanks,
Wei.
