Re: [PATCH net-next v2 1/9] octeon_ep: defer probe if firmware not ready

From: Leon Romanovsky
Date: Wed Nov 30 2022 - 04:24:56 EST


On Tue, Nov 29, 2022 at 05:09:24AM -0800, Veerasenareddy Burru wrote:
> Defer probe if firmware is not ready for device usage.
>
> Signed-off-by: Veerasenareddy Burru <vburru@xxxxxxxxxxx>
> Signed-off-by: Abhijit Ayarekar <aayarekar@xxxxxxxxxxx>
> Signed-off-by: Satananda Burla <sburla@xxxxxxxxxxx>
> ---
> v1 -> v2:
> * was scheduling workqueue task to wait for firmware ready,
> to probe/initialize the device.
> * now, removed the workqueue task; the probe returns EPROBE_DEFER,
> if firmware is not ready.
> * removed device status oct->status, as it is not required with the
> modified implementation.
>
> .../ethernet/marvell/octeon_ep/octep_main.c | 26 +++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
> index 5a898fb88e37..aa7d0ced9807 100644
> --- a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
> +++ b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
> @@ -1017,6 +1017,25 @@ static void octep_device_cleanup(struct octep_device *oct)
> oct->conf = NULL;
> }
>
> +static u8 get_fw_ready_status(struct pci_dev *pdev)

Please change this function to return bool, you are not interested in
status.

> +{
> + u32 pos = 0;
> + u16 vsec_id;
> + u8 status;
> +
> + while ((pos = pci_find_next_ext_capability(pdev, pos,
> + PCI_EXT_CAP_ID_VNDR))) {
> + pci_read_config_word(pdev, pos + 4, &vsec_id);
> +#define FW_STATUS_VSEC_ID 0xA3
> + if (vsec_id == FW_STATUS_VSEC_ID) {

Success oriented flow, plase
if (vsec_id != FW_STATUS_VSEC_ID)
cotitnue;

....

> + pci_read_config_byte(pdev, (pos + 8), &status);
> + dev_info(&pdev->dev, "Firmware ready %u\n", status);
> + return status;
> + }
> + }
> + return 0;
> +}
> +
> /**
> * octep_probe() - Octeon PCI device probe handler.
> *
> @@ -1053,6 +1072,13 @@ static int octep_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> pci_enable_pcie_error_reporting(pdev);
> pci_set_master(pdev);
>
> +#define FW_STATUS_READY 1
> + if (get_fw_ready_status(pdev) != FW_STATUS_READY) {

No need to this new define if you change get_fw_ready_status() to return
true/false.

And I think that you can put this check earlier in octep_probe().

Thanks

> + dev_notice(&pdev->dev, "Firmware not ready; defer probe.\n");
> + err = -EPROBE_DEFER;
> + goto err_alloc_netdev;
> + }
> +
> netdev = alloc_etherdev_mq(sizeof(struct octep_device),
> OCTEP_MAX_QUEUES);
> if (!netdev) {
> --
> 2.36.0
>