Re: [PATCH 4/4] PCI: pci-epf-test: Add support to defer core initialization

[Kishon Vijay Abraham I]

Hi,

On 13/11/19 2:38 PM, Vidya Sagar wrote:
> Add support to defer core initialization and to receive a notifier
> when core is ready to accommodate platforms where core is not for
> initialization untile reference clock from host is available.
> 
> Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
> ---
>  drivers/pci/endpoint/functions/pci-epf-test.c | 114 ++++++++++++------
>  1 file changed, 77 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index bddff15052cc..068024fab544 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -360,18 +360,6 @@ static void pci_epf_test_cmd_handler(struct work_struct *work)
>  			   msecs_to_jiffies(1));
>  }
>  
> -static int pci_epf_test_notifier(struct notifier_block *nb, unsigned long val,
> -				 void *data)
> -{
> -	struct pci_epf *epf = container_of(nb, struct pci_epf, nb);
> -	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
> -
> -	queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
> -			   msecs_to_jiffies(1));
> -
> -	return NOTIFY_OK;
> -}
> -
>  static void pci_epf_test_unbind(struct pci_epf *epf)
>  {
>  	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
> @@ -428,6 +416,78 @@ static int pci_epf_test_set_bar(struct pci_epf *epf)
>  	return 0;
>  }
>  
> +static int pci_epf_test_core_init(struct pci_epf *epf)
> +{
> +	struct pci_epf_header *header = epf->header;
> +	const struct pci_epc_features *epc_features;
> +	struct pci_epc *epc = epf->epc;
> +	struct device *dev = &epf->dev;
> +	bool msix_capable = false;
> +	bool msi_capable = true;
> +	int ret;
> +
> +	epc_features = pci_epc_get_features(epc, epf->func_no);
> +	if (epc_features) {
> +		msix_capable = epc_features->msix_capable;
> +		msi_capable = epc_features->msi_capable;
> +	}
> +
> +	ret = pci_epc_write_header(epc, epf->func_no, header);
> +	if (ret) {
> +		dev_err(dev, "Configuration header write failed\n");
> +		return ret;
> +	}
> +
> +	ret = pci_epf_test_set_bar(epf);
> +	if (ret)
> +		return ret;
> +
> +	if (msi_capable) {
> +		ret = pci_epc_set_msi(epc, epf->func_no, epf->msi_interrupts);
> +		if (ret) {
> +			dev_err(dev, "MSI configuration failed\n");
> +			return ret;
> +		}
> +	}
> +
> +	if (msix_capable) {
> +		ret = pci_epc_set_msix(epc, epf->func_no, epf->msix_interrupts);
> +		if (ret) {
> +			dev_err(dev, "MSI-X configuration failed\n");
> +			return ret;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int pci_epf_test_notifier(struct notifier_block *nb, unsigned long val,
> +				 void *data)
> +{
> +	struct pci_epf *epf = container_of(nb, struct pci_epf, nb);
> +	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
> +	int ret;
> +
> +	switch (val) {
> +	case CORE_INIT:
> +		ret = pci_epf_test_core_init(epf);
> +		if (ret)
> +			return NOTIFY_BAD;
> +		break;
> +
> +	case LINK_UP:
> +		queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
> +				   msecs_to_jiffies(1));
> +		break;
> +
> +	default:
> +		dev_err(&epf->dev, "Invalid EPF test notifier event\n");
> +		return NOTIFY_BAD;
> +	}
> +
> +	return NOTIFY_OK;
> +}
> +
>  static int pci_epf_test_alloc_space(struct pci_epf *epf)
>  {
>  	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
> @@ -496,12 +556,11 @@ static int pci_epf_test_bind(struct pci_epf *epf)
>  {
>  	int ret;
>  	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
> -	struct pci_epf_header *header = epf->header;
>  	const struct pci_epc_features *epc_features;
>  	enum pci_barno test_reg_bar = BAR_0;
>  	struct pci_epc *epc = epf->epc;
> -	struct device *dev = &epf->dev;
>  	bool linkup_notifier = false;
> +	bool skip_core_init = false;
>  	bool msix_capable = false;
>  	bool msi_capable = true;
>  
> @@ -511,6 +570,7 @@ static int pci_epf_test_bind(struct pci_epf *epf)
>  	epc_features = pci_epc_get_features(epc, epf->func_no);
>  	if (epc_features) {
>  		linkup_notifier = epc_features->linkup_notifier;
> +		skip_core_init = epc_features->skip_core_init;
>  		msix_capable = epc_features->msix_capable;
>  		msi_capable = epc_features->msi_capable;

Are these used anywhere in this function?
>  		test_reg_bar = pci_epc_get_first_free_bar(epc_features);
> @@ -520,34 +580,14 @@ static int pci_epf_test_bind(struct pci_epf *epf)
>  	epf_test->test_reg_bar = test_reg_bar;
>  	epf_test->epc_features = epc_features;
>  
> -	ret = pci_epc_write_header(epc, epf->func_no, header);
> -	if (ret) {
> -		dev_err(dev, "Configuration header write failed\n");
> -		return ret;
> -	}
> -
>  	ret = pci_epf_test_alloc_space(epf);
>  	if (ret)
>  		return ret;
>  
> -	ret = pci_epf_test_set_bar(epf);
> -	if (ret)
> -		return ret;
> -
> -	if (msi_capable) {
> -		ret = pci_epc_set_msi(epc, epf->func_no, epf->msi_interrupts);
> -		if (ret) {
> -			dev_err(dev, "MSI configuration failed\n");
> -			return ret;
> -		}
> -	}
> -
> -	if (msix_capable) {
> -		ret = pci_epc_set_msix(epc, epf->func_no, epf->msix_interrupts);
> -		if (ret) {
> -			dev_err(dev, "MSI-X configuration failed\n");
> +	if (!skip_core_init) {
> +		ret = pci_epf_test_core_init(epf);
> +		if (ret)
>  			return ret;
> -		}
>  	}
>  
>  	if (linkup_notifier) {

This could as well be moved to pci_epf_test_core_init().

Thanks
Kishon