[PATCH][SRU][OEM-5.10] UBUNTU: SAUCE: r8169: introduce polling method for link change

[Krzysztof Kozlowski]

On 03/06/2021 06:20, Koba Ko wrote:
> BugLink: https://bugs.launchpad.net/bugs/1930645
> 
> For RTL8106E, it's a Fast-ethernet chip.
> If ASPM is enabled, the link chang interrupt wouldn't be triggered
> immediately and must wait a very long time to get link change interrupt.
> Even the link change interrupt isn't triggered, the phy link is already
> established.
> 
> Introduce a polling method to watch the status of phy link and disable
> the link change interrupt.
> Also add a quirk for those realtek devices have the same issue.
> 
> Signed-off-by: Koba Ko <koba.ko at canonical.com>
> ---
>  drivers/net/ethernet/realtek/r8169.h      |   2 +
>  drivers/net/ethernet/realtek/r8169_main.c | 112 ++++++++++++++++++----
>  2 files changed, 98 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/net/ethernet/realtek/r8169.h b/drivers/net/ethernet/realtek/r8169.h
> index 2728df46ec41..a8c71adb1b57 100644
> --- a/drivers/net/ethernet/realtek/r8169.h
> +++ b/drivers/net/ethernet/realtek/r8169.h
> @@ -11,6 +11,8 @@
>  #include <linux/types.h>
>  #include <linux/phy.h>
>  
> +#define RTL8169_LINK_TIMEOUT (1 * HZ)
> +
>  enum mac_version {
>  	/* support for ancient RTL_GIGA_MAC_VER_01 has been removed */
>  	RTL_GIGA_MAC_VER_02,
> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index 2c89cde7da1e..70aacc83d641 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c
> @@ -178,6 +178,11 @@ static const struct pci_device_id rtl8169_pci_tbl[] = {
>  
>  MODULE_DEVICE_TABLE(pci, rtl8169_pci_tbl);
>  
> +static const struct pci_device_id rtl8169_linkChg_polling_enabled[] = {

This looks unused - what piece references it?

Best regards,
Krzysztof

> +	{ PCI_VDEVICE(REALTEK, 0x8136), RTL_CFG_NO_GBIT },
> +	{ 0 }
> +};
> +
>  enum rtl_registers {
>  	MAC0		= 0,	/* Ethernet hardware address. */
>  	MAC4		= 4,
> @@ -618,6 +623,7 @@ struct rtl8169_private {
>  	u16 cp_cmd;
>  	u32 irq_mask;
>  	struct clk *clk;
> +	struct timer_list link_timer;
>  
>  	struct {
>  		DECLARE_BITMAP(flags, RTL_FLAG_MAX);
> @@ -1179,6 +1185,16 @@ static void rtl8168ep_stop_cmac(struct rtl8169_private *tp)
>  	RTL_W8(tp, IBCR0, RTL_R8(tp, IBCR0) & ~0x01);
>  }
>  
> +static int rtl_link_chng_polling_quirk(struct rtl8169_private *tp)
> +{
> +	struct pci_dev *pdev = tp->pci_dev;
> +
> +	if (pdev->vendor == 0x10ec && pdev->device == 0x8136 && !tp->supports_gmii)
> +		return 1;
> +
> +	return 0;
> +}
> +
>  static void rtl8168dp_driver_start(struct rtl8169_private *tp)
>  {
>  	r8168dp_oob_notify(tp, OOB_CMD_DRIVER_START);
> @@ -4608,6 +4624,75 @@ static void rtl_task(struct work_struct *work)
>  	rtnl_unlock();
>  }
>  
> +static void r8169_phylink_handler(struct net_device *ndev)
> +{
> +	struct rtl8169_private *tp = netdev_priv(ndev);
> +
> +	if (netif_carrier_ok(ndev)) {
> +		rtl_link_chg_patch(tp);
> +		pm_request_resume(&tp->pci_dev->dev);
> +	} else {
> +		pm_runtime_idle(&tp->pci_dev->dev);
> +	}
> +
> +	if (net_ratelimit())
> +		phy_print_status(tp->phydev);
> +}
> +
> +static unsigned int
> +rtl8169_xmii_link_ok(struct net_device *dev)
> +{
> +	struct rtl8169_private *tp = netdev_priv(dev);
> +	unsigned int retval;
> +
> +	retval = (RTL_R8(tp, PHYstatus) & LinkStatus) ? 1 : 0;
> +
> +	return retval;
> +}
> +
> +static void
> +rtl8169_check_link_status(struct net_device *dev)
> +{
> +	struct rtl8169_private *tp = netdev_priv(dev);
> +	int link_status_on;
> +
> +	link_status_on = rtl8169_xmii_link_ok(dev);
> +
> +	if (netif_carrier_ok(dev) == link_status_on)
> +		return;
> +
> +	phy_mac_interrupt(tp->phydev);
> +
> +	r8169_phylink_handler (dev);
> +}
> +
> +static void rtl8169_link_timer(struct timer_list *t)
> +{
> +	struct rtl8169_private *tp = from_timer(tp, t, link_timer);
> +	struct net_device *dev = tp->dev;
> +	struct timer_list *timer = t;
> +	unsigned long flags;
> +
> +	rtl8169_check_link_status(dev);
> +
> +	if (timer_pending(&tp->link_timer))
> +		return;
> +
> +	mod_timer(timer, jiffies + RTL8169_LINK_TIMEOUT);
> +}
> +
> +static inline void rtl8169_delete_link_timer(struct net_device *dev, struct timer_list *timer)
> +{
> +	del_timer_sync(timer);
> +}
> +
> +static inline void rtl8169_request_link_timer(struct net_device *dev)
> +{
> +	struct rtl8169_private *tp = netdev_priv(dev);
> +
> +	timer_setup(&tp->link_timer, rtl8169_link_timer, TIMER_INIT_FLAGS);
> +}
> +
>  static int rtl8169_poll(struct napi_struct *napi, int budget)
>  {
>  	struct rtl8169_private *tp = container_of(napi, struct rtl8169_private, napi);
> @@ -4624,21 +4709,6 @@ static int rtl8169_poll(struct napi_struct *napi, int budget)
>  	return work_done;
>  }
>  
> -static void r8169_phylink_handler(struct net_device *ndev)
> -{
> -	struct rtl8169_private *tp = netdev_priv(ndev);
> -
> -	if (netif_carrier_ok(ndev)) {
> -		rtl_link_chg_patch(tp);
> -		pm_request_resume(&tp->pci_dev->dev);
> -	} else {
> -		pm_runtime_idle(&tp->pci_dev->dev);
> -	}
> -
> -	if (net_ratelimit())
> -		phy_print_status(tp->phydev);
> -}
> -
>  static int r8169_phy_connect(struct rtl8169_private *tp)
>  {
>  	struct phy_device *phydev = tp->phydev;
> @@ -4769,6 +4839,10 @@ static int rtl_open(struct net_device *dev)
>  		goto err_free_irq;
>  
>  	rtl8169_up(tp);
> +
> +	if (rtl_link_chng_polling_quirk(tp))
> +		mod_timer(&tp->link_timer, jiffies + RTL8169_LINK_TIMEOUT);
> +
>  	rtl8169_init_counter_offsets(tp);
>  	netif_start_queue(dev);
>  out:
> @@ -4991,7 +5065,10 @@ static const struct net_device_ops rtl_netdev_ops = {
>  
>  static void rtl_set_irq_mask(struct rtl8169_private *tp)
>  {
> -	tp->irq_mask = RxOK | RxErr | TxOK | TxErr | LinkChg;
> +	tp->irq_mask = RxOK | RxErr | TxOK | TxErr;
> +
> +	if (!rtl_link_chng_polling_quirk(tp))
> +		tp->irq_mask |= LinkChg;
>  
>  	if (tp->mac_version <= RTL_GIGA_MAC_VER_06)
>  		tp->irq_mask |= SYSErr | RxOverflow | RxFIFOOver;
> @@ -5436,6 +5513,9 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	if (pci_dev_run_wake(pdev))
>  		pm_runtime_put_sync(&pdev->dev);
>  
> +	if (rtl_link_chng_polling_quirk(tp))
> +		rtl8169_request_link_timer(dev);
> +
>  	return 0;
>  }
>