RE: [EXT] Re: [PATCH net-next v3 1/7] octeon_ep: defer probe if firmware not ready

[Veerasenareddy Burru]

> -----Original Message-----
> From: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx>
> Sent: Tuesday, February 14, 2023 9:32 AM
> To: Veerasenareddy Burru <vburru@xxxxxxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Abhijit Ayarekar
> <aayarekar@xxxxxxxxxxx>; Sathesh B Edara <sedara@xxxxxxxxxxx>;
> Satananda Burla <sburla@xxxxxxxxxxx>; linux-doc@xxxxxxxxxxxxxxx; David S.
> Miller <davem@xxxxxxxxxxxxx>; Eric Dumazet <edumazet@xxxxxxxxxx>;
> Jakub Kicinski <kuba@xxxxxxxxxx>; Paolo Abeni <pabeni@xxxxxxxxxx>
> Subject: [EXT] Re: [PATCH net-next v3 1/7] octeon_ep: defer probe if
> firmware not ready
> 
> External Email
> 
> ----------------------------------------------------------------------
> On Mon, Feb 13, 2023 at 09:14:16PM -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>
> > ---
> > v2 -> v3:
> >  * fix review comments
> >    https://urldefense.proofpoint.com/v2/url?u=https-
> 3A__lore.kernel.org_all_Y4chWyR6qTlptkTE-
> 40unreal_&d=DwIBAg&c=nKjWec2b6R0mOyPaz7xtfQ&r=XkP_75lnbPIeeucsP
> X36ZgjiMqEKttwZfwNyWMCLjT0&m=4b7d0RrdHBeSeuVxcgazZ-
> kuSb9u5rGArB5Mio0glbruzVrVD25vZP2M2f1jPteh&s=JhMZ44LA1ICu-
> gf3_8cI2F_pN7OFsWMNHp2Od7u26Gk&e=
> >    - change get_fw_ready_status() to return bool
> >    - fix the success oriented flow while looking for
> >      PCI extended capability
> >
> > 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..5620df4c6d55 100644
> > --- a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
> > +++ b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
> > @@ -1017,6 +1017,26 @@ static void octep_device_cleanup(struct
> octep_device *oct)
> >  	oct->conf = NULL;
> >  }
> >
> > +static bool get_fw_ready_status(struct pci_dev *pdev) {
> > +	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)
> > +			continue;
> > +
> > +		pci_read_config_byte(pdev, (pos + 8), &status);
> > +		dev_info(&pdev->dev, "Firmware ready status = %u\n",
> status);
> > +		return status ? true : false;
> 
> nit:
> 
> return !!status;
> 
> ?
> 

Thank you for the feedback. Will update in next revision.

> > +	}
> > +	return false;
> > +}
> > +
> >  /**
> >   * octep_probe() - Octeon PCI device probe handler.
> >   *
> > @@ -1053,6 +1073,12 @@ static int octep_probe(struct pci_dev *pdev,
> const struct pci_device_id *ent)
> >  	pci_enable_pcie_error_reporting(pdev);
> >  	pci_set_master(pdev);
> >
> > +	if (!get_fw_ready_status(pdev)) {
> > +		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
> >