RE: [PATCH v5 1/2] PCI: hv: Make the code arch neutral by adding arch specific interfaces

[Michael Kelley <mikelley@microsoft.com>]

From: Sunil Muthuswamy <sunilmut@linux.microsoft.com> Sent: Wednesday, November 10, 2021 11:45 AM
> 
> Encapsulate arch dependencies in Hyper-V vPCI through a set of
> arch-dependent interfaces. Adding these arch specific interfaces will
> allow for an implementation for other architectures, such as arm64.
> 
> There are no functional changes expected from this patch.
> 
> Signed-off-by: Sunil Muthuswamy <sunilmut@microsoft.com>
> ---
> In v2, v3, v4 & v5:
>  Changes are described in the cover letter. No change from v4 -> v5.
> 
>  arch/x86/include/asm/hyperv-tlfs.h  | 33 ++++++++++++
>  arch/x86/include/asm/mshyperv.h     |  7 ---
>  drivers/pci/controller/pci-hyperv.c | 79 ++++++++++++++++++++---------
>  include/asm-generic/hyperv-tlfs.h   | 33 ------------
>  4 files changed, 87 insertions(+), 65 deletions(-)
> 

[snip]

> diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
> index eaec915ffe62..03e07a4f0e3f 100644
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -43,9 +43,6 @@
>  #include <linux/pci-ecam.h>
>  #include <linux/delay.h>
>  #include <linux/semaphore.h>
> -#include <linux/irqdomain.h>
> -#include <asm/irqdomain.h>
> -#include <asm/apic.h>
>  #include <linux/irq.h>
>  #include <linux/msi.h>
>  #include <linux/hyperv.h>
> @@ -583,6 +580,42 @@ struct hv_pci_compl {
> 
>  static void hv_pci_onchannelcallback(void *context);
> 
> +#ifdef CONFIG_X86
> +#define DELIVERY_MODE	APIC_DELIVERY_MODE_FIXED
> +#define FLOW_HANDLER	handle_edge_irq
> +#define FLOW_NAME	"edge"
> +
> +static int hv_pci_irqchip_init(void)
> +{
> +	return 0;
> +}
> +
> +static struct irq_domain *hv_pci_get_root_domain(void)
> +{
> +	return x86_vector_domain;
> +}
> +
> +static unsigned int hv_msi_get_int_vector(struct irq_data *data)
> +{
> +	struct irq_cfg *cfg = irqd_cfg(data);
> +
> +	return cfg->vector;
> +}
> +
> +static void hv_set_msi_entry_from_desc(union hv_msi_entry *msi_entry,
> +				       struct msi_desc *msi_desc)
> +{
> +	msi_entry->address.as_uint32 = msi_desc->msg.address_lo;
> +	msi_entry->data.as_uint32 = msi_desc->msg.data;
> +}
> +
> +static int hv_msi_prepare(struct irq_domain *domain, struct device *dev,
> +			  int nvec, msi_alloc_info_t *info)
> +{
> +	return pci_msi_prepare(domain, dev, nvec, info);
> +}
> +#endif // CONFIG_X86

Nit:  Use "C" style comments. I.e.:

#endif /* CONFIG_X86 */

Michael