Hi Stefano,
> On 23 Sep 2021, at 1:03 am, Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> On Wed, 22 Sep 2021, Rahul Singh wrote:
>> pci_init(..) will be called during xen startup to initialize and probe
>> the PCI host-bridge driver.
>>
>> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
>> ---
>> Change in v2:
>> - ACPI init function to return int
>> - pci_segments_init() called before dt/acpi init
>> ---
>> xen/arch/arm/pci/pci.c | 54 ++++++++++++++++++++++++++++++++++++
>> xen/include/asm-arm/device.h | 1 +
>> 2 files changed, 55 insertions(+)
>>
>> diff --git a/xen/arch/arm/pci/pci.c b/xen/arch/arm/pci/pci.c
>> index a7a7bc3213..71fa532842 100644
>> --- a/xen/arch/arm/pci/pci.c
>> +++ b/xen/arch/arm/pci/pci.c
>> @@ -12,6 +12,10 @@
>> * along with this program. If not, see <http://www.gnu.org/licenses/>.
>> */
>>
>> +#include <xen/acpi.h>
>> +#include <xen/device_tree.h>
>> +#include <xen/errno.h>
>> +#include <xen/init.h>
>> #include <xen/pci.h>
>>
>> /*
>> @@ -22,6 +26,56 @@ int arch_pci_clean_pirqs(struct domain *d)
>> return 0;
>> }
>>
>> +static int __init dt_pci_init(void)
>> +{
>> + struct dt_device_node *np;
>> + int rc;
>> +
>> + dt_for_each_device_node(dt_host, np)
>> + {
>> + rc = device_init(np, DEVICE_PCI, NULL);
>> + if( !rc )
>> + continue;
>
> This is a NIT, so feel free to code it as you prefer, but I would write
> it as follows for simplicity:
>
>
> /* comment about EBADF and ENODEV */
> if ( !rc || rc == -EBADF || rc == -ENODEV )
> continue;
> return rc;
Ack.
>
>
>> + /*
>> + * Ignore the following error codes:
>> + * - EBADF: Indicate the current is not an pci
> ^ device ^a ^ device
Ac.
>
>
>> + * - ENODEV: The pci device is not present or cannot be used by
>> + * Xen.
>> + */
>> + else if ( rc != -EBADF && rc != -ENODEV )
>> + {
>> + printk(XENLOG_ERR "No driver found in XEN or driver init error.\n");
>> + return rc;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +#ifdef CONFIG_ACPI
>> +static int __init acpi_pci_init(void)
>> +{
>> + printk(XENLOG_ERR "ACPI pci init not supported \n");
>> + return 0;
>
> Should return ENOSYS or EOPNOTSUPP?
I think EOPNOTSUPP is right choice.
Regards,
Rahul
>
>
>> +}
>> +#else
>> +static inline int __init acpi_pci_init(void)
>
> Not sure I would inline it but OK either way
>
>
>> +{
>> + return -EINVAL;
>> +}
>> +#endif
>> +
>> +static int __init pci_init(void)
>> +{
>> + pci_segments_init();
>> +
>> + if ( acpi_disabled )
>> + return dt_pci_init();
>> + else
>> + return acpi_pci_init();
>> +}
>> +__initcall(pci_init);
>> +
>> /*
>> * Local variables:
>> * mode: C
>> diff --git a/xen/include/asm-arm/device.h b/xen/include/asm-arm/device.h
>> index ee7cff2d44..5ecd5e7bd1 100644
>> --- a/xen/include/asm-arm/device.h
>> +++ b/xen/include/asm-arm/device.h
>> @@ -34,6 +34,7 @@ enum device_class
>> DEVICE_SERIAL,
>> DEVICE_IOMMU,
>> DEVICE_GIC,
>> + DEVICE_PCI,
>> /* Use for error */
>> DEVICE_UNKNOWN,
>> };
>> --
>> 2.17.1