Date:   Tue, 14 Feb 2023 18:32:05 +0100
From:   Maciej Fijalkowski <maciej.fijalkowski@intel.com>
To:     Veerasenareddy Burru <vburru@marvell.com>
CC:     <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <aayarekar@marvell.com>, <sedara@marvell.com>,
        <sburla@marvell.com>, <linux-doc@vger.kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        "Eric Dumazet" <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>
Subject: Re: [PATCH net-next v3 1/7] octeon_ep: defer probe if firmware not
 ready
Message-ID: <Y+vFlfakHj33DEkt@boxer>
References: <20230214051422.13705-1-vburru@marvell.com>
 <20230214051422.13705-2-vburru@marvell.com>
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <20230214051422.13705-2-vburru@marvell.com>
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?iDDXEzqioIqixVtbJJeI01TMrnjdIlP6Cb22O2Tz66xJkiOg2dZOb89Lr2Gx?=
 =?us-ascii?Q?XqVP9ZatHTAoQLT0mMx64Ok+FDgePBpqyRCuJ9azN7/y7rD5LmcsG5+4vjVl?=
 =?us-ascii?Q?5fE46jB+jj2X1A3v7fmph/p6ZjQlmrSHzf7ZdWS4Qb+VCLGCUi8lNtZrJyLY?=
 =?us-ascii?Q?IGoj+xvYbMSLl5kw151niVvedvvS0wtvW3RlTvOooS1UyM0kpVVlfdBIvZsp?=
 =?us-ascii?Q?S44WcNSb1O6T4LBpbK3mqD1dezlq4837nnDq2VcHJCPmCPsjqums7Bk+I7Xv?=
 =?us-ascii?Q?7Uo0FnuII0d/mCvfyg879zTYKvPccn2PxqoxjuhuNbP1LKjDt5J4uXPTFCFq?=
 =?us-ascii?Q?oSuDvAGnZkK3pVcMt4EhPI2YXqeOHz40BefHfhOa4lhLvtqnW9Ql3dB02b3s?=
 =?us-ascii?Q?Z4/Bna9TQV9AJkaTHF8IgVMyysqHv7uq4EKg+lNc+A+EZInLY1y1upycCa8Z?=
 =?us-ascii?Q?pAZqfLaNjQFRjIPP/VRaCG1PkXm+aC4czUi7pBm+q6Dzlx7YipiGOjhGI31k?=
 =?us-ascii?Q?VUbQwVhwWmsFrzp3qV4Y0Yd2ps+tm23+3wIvydAESOVmYF4pTz/y3BdXwcgS?=
 =?us-ascii?Q?qPM5W3JkcUHcZCkViqxAUU6NwKlQpnEC5xM1oPHfywwOrCTg2CGaWqYzxhGl?=
 =?us-ascii?Q?iWKb6sw0JdCTDqYHFyRMvO6pTApIakAZh+xCuIGJtwn6ISp6BlEj5nT6szi8?=
 =?us-ascii?Q?uouEBIlypiCK2vu22TpkUVMx/AGtLnsmhhm1qfuIiY9+j5uYES+Rk6LaduvR?=
 =?us-ascii?Q?L/SXWfxTAIXeJide0LMEiDBSpLpZ/779RWK17ucWqD45liPOE3Ro2lbngoyO?=
 =?us-ascii?Q?Lg1q1E1Vjt5T6Y457xJOLN3rzKH+bTjl71N5W/5Aa+p3mOWXcWBAZzyvD1uM?=
 =?us-ascii?Q?PpW/3eBb9sftTfYoPhTcxRZrWQHF7bhGzBA1W31cwY74a8G4eEW0lQgataag?=
 =?us-ascii?Q?TUnuYL1Bgvw7T2ECm/g/1bkniiSg233s2PBhlYe0btUPK7aZv3h5T/d8x/wC?=
 =?us-ascii?Q?A/ZwYHvP3QoUHLilM0zUjmZ3FUfKE/zyfwAciUjZOL8VTfeERqax/R/qYiGH?=
 =?us-ascii?Q?7yfnddNVrsbZ4i2Wz32M9lk8bkd7gqTaWtfnsCCy7kkXykShlsSbPrBnFVMU?=
 =?us-ascii?Q?zUQWBs091TDmkspR+b/9QozJDMNH+DPra4KYTxWYCnwxQpTKHvnoZ92f9LVS?=
 =?us-ascii?Q?jCkIkNzeMNLlGC7pJf+z2Z5s/K2eGSPpbpinGwyEW29mgqklvth2yj/B+IfS?=
 =?us-ascii?Q?EdgSUdajcH2AlT4PoFJhB351tsiZylvaxjq6kaRFm8VSDO0YJxLD/cLPUjxT?=
 =?us-ascii?Q?8BmJJL+/c7Wri/oi4ayQAgrLpZiWs7zsLLTXV76PLmXRxtIfXYpYkLSl/DYu?=
 =?us-ascii?Q?AASyFLsZJi/PpZeo+T7RogKV+T+xqAlxWcdw8vwT7FxUvJvjWKqXxvuO5C6S?=
 =?us-ascii?Q?Xf89FiWYNJIEPVEhcqQ7wRX90qXhM7zH28j2Pbrx6YRMgTlMIRWgmwtjaTYy?=
 =?us-ascii?Q?YORxmJfzC2+wmPSmrVGzvrgF5GOaDaHXd3tKIrMJsbk4kc7DmTjJsn/X0Hkl?=
 =?us-ascii?Q?4jEqk7n/kezThtBqH1bUHlVpFlF68BwR6NTh7mt06Kwu4LRbKn1AIpvxRCoN?=
 =?us-ascii?Q?0WmSvTAqjhdTKYPsDP4WqRA=3D?=
X-MS-Exchange-CrossTenant-Network-Message-Id: f1d29ff7-c4ac-432d-3413-08db0eb1870b
X-MS-Exchange-CrossTenant-AuthSource: DM4PR11MB6117.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Feb 2023 17:33:04.2590
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: /TQRASIGiW2jKhX9QjCMVP66TRNTwtXtNVPVLW5U42uYqkuPD7ioLp/ZiBpyadaWucYQl5vUG29u6yhxs1Gv7licZRfnNTSYxoEkv+kI6A8=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR11MB5584
X-OriginatorOrg: intel.com
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

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@marvell.com>
> Signed-off-by: Abhijit Ayarekar <aayarekar@marvell.com>
> Signed-off-by: Satananda Burla <sburla@marvell.com>
> ---
> v2 -> v3:
>  * fix review comments
>    https://lore.kernel.org/all/Y4chWyR6qTlptkTE@unreal/
>    - 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;

?

> +	}
> +	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
>