Re: [PATCH] PCI: vmd: Reset VMD config register between soft reboots

[Jonathan Derrick <jonathan.derrick@linux.dev>]

On 3/15/23 3:51 PM, Patel, Nirmal wrote:
> On 2/24/2023 1:28 PM, Nirmal Patel wrote:
>> VMD driver can disable or enable MSI remapping by changing
>> VMCONFIG_MSI_REMAP register. This register needs to be set to the
>> default value during soft reboots. Drives failed to enumerate
>> when Windows boots after performing a soft reboot from Linux.
>> Windows doesn't support MSI remapping disable feature and stale
>> register value hinders Windows VMD driver initialization process.
>> Adding vmd_shutdown function to make sure to set the VMCONFIG
>> register to the default value.
>>
>> Signed-off-by: Nirmal Patel <nirmal.patel@linux.intel.com>
>> Fixes: ee81ee84f873 ("PCI: vmd: Disable MSI-X remapping when possible")
>> ---
>>   drivers/pci/controller/vmd.c | 8 ++++++++
>>   1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
>> index 769eedeb8802..50a187a29a1d 100644
>> --- a/drivers/pci/controller/vmd.c
>> +++ b/drivers/pci/controller/vmd.c
>> @@ -979,6 +979,13 @@ static void vmd_remove(struct pci_dev *dev)
>>   	ida_simple_remove(&vmd_instance_ida, vmd->instance);
>>   }
>>   
>> +static void vmd_shutdown(struct pci_dev *dev)
>> +{
>> +        struct vmd_dev *vmd = pci_get_drvdata(dev);
>> +
>> +        vmd_remove_irq_domain(vmd);
>> +}
>> +
>>   #ifdef CONFIG_PM_SLEEP
>>   static int vmd_suspend(struct device *dev)
>>   {
>> @@ -1056,6 +1063,7 @@ static struct pci_driver vmd_drv = {
>>   	.id_table	= vmd_ids,
>>   	.probe		= vmd_probe,
>>   	.remove		= vmd_remove,
>> +	.shutdown	= vmd_shutdown,
>>   	.driver		= {
>>   		.pm	= &vmd_dev_pm_ops,
>>   	},
> 
> Gentle ping.
> 
> Thanks
> 

LGTM
Reviewed-by: Jon Derrick <jonathan.derrick@linux.dev>