diff mbox series

[v3] rtw88: Disable PCIe ASPM while doing NAPI poll on 8821CE

Message ID 20211215065508.313330-1-kai.heng.feng@canonical.com (mailing list archive)
State Changes Requested
Delegated to: Kalle Valo
Headers show
Series [v3] rtw88: Disable PCIe ASPM while doing NAPI poll on 8821CE | expand

Commit Message

Kai-Heng Feng Dec. 15, 2021, 6:55 a.m. UTC
Many Intel based platforms face system random freeze after commit
9e2fd29864c5 ("rtw88: add napi support").

The commit itself shouldn't be the culprit. My guess is that the 8821CE
only leaves ASPM L1 for a short period when IRQ is raised. Since IRQ is
masked during NAPI polling, the PCIe link stays at L1 and makes RX DMA
extremely slow. Eventually the RX ring becomes messed up:
[ 1133.194697] rtw_8821ce 0000:02:00.0: pci bus timeout, check dma status

Since the 8821CE hardware may fail to leave ASPM L1, manually do it in
the driver to resolve the issue.

Fixes: 9e2fd29864c5 ("rtw88: add napi support")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215131
BugLink: https://bugs.launchpad.net/bugs/1927808
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
v3:
 - Move the module parameter to be part of private struct.
 - Ensure link_usage never goes below zero.

v2:
 - Add default value for module parameter.

 drivers/net/wireless/realtek/rtw88/pci.c | 61 ++++++++----------------
 drivers/net/wireless/realtek/rtw88/pci.h |  2 +
 2 files changed, 21 insertions(+), 42 deletions(-)

Comments

Jian-Hong Pan Dec. 15, 2021, 7:15 a.m. UTC | #1
Tried to apply this patch for testing.  But it seems conflicting to
commit c81edb8dddaa "rtw88: add quirk to disable pci caps on HP 250 G7
Notebook PC" in wireless-drivers-next repo.

Jian-Hong Pan

Kai-Heng Feng <kai.heng.feng@canonical.com> 於 2021年12月15日 週三 下午2:55寫道:
>
> Many Intel based platforms face system random freeze after commit
> 9e2fd29864c5 ("rtw88: add napi support").
>
> The commit itself shouldn't be the culprit. My guess is that the 8821CE
> only leaves ASPM L1 for a short period when IRQ is raised. Since IRQ is
> masked during NAPI polling, the PCIe link stays at L1 and makes RX DMA
> extremely slow. Eventually the RX ring becomes messed up:
> [ 1133.194697] rtw_8821ce 0000:02:00.0: pci bus timeout, check dma status
>
> Since the 8821CE hardware may fail to leave ASPM L1, manually do it in
> the driver to resolve the issue.
>
> Fixes: 9e2fd29864c5 ("rtw88: add napi support")
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215131
> BugLink: https://bugs.launchpad.net/bugs/1927808
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> ---
> v3:
>  - Move the module parameter to be part of private struct.
>  - Ensure link_usage never goes below zero.
>
> v2:
>  - Add default value for module parameter.
>
>  drivers/net/wireless/realtek/rtw88/pci.c | 61 ++++++++----------------
>  drivers/net/wireless/realtek/rtw88/pci.h |  2 +
>  2 files changed, 21 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/net/wireless/realtek/rtw88/pci.c b/drivers/net/wireless/realtek/rtw88/pci.c
> index a7a6ebfaa203c..08cf66141889b 100644
> --- a/drivers/net/wireless/realtek/rtw88/pci.c
> +++ b/drivers/net/wireless/realtek/rtw88/pci.c
> @@ -2,7 +2,6 @@
>  /* Copyright(c) 2018-2019  Realtek Corporation
>   */
>
> -#include <linux/dmi.h>
>  #include <linux/module.h>
>  #include <linux/pci.h>
>  #include "main.h"
> @@ -1409,7 +1408,11 @@ static void rtw_pci_link_ps(struct rtw_dev *rtwdev, bool enter)
>          * throughput. This is probably because the ASPM behavior slightly
>          * varies from different SOC.
>          */
> -       if (rtwpci->link_ctrl & PCI_EXP_LNKCTL_ASPM_L1)
> +       if (!(rtwpci->link_ctrl & PCI_EXP_LNKCTL_ASPM_L1))
> +               return;
> +
> +       if ((enter && atomic_dec_if_positive(&rtwpci->link_usage) == 0) ||
> +           (!enter && atomic_inc_return(&rtwpci->link_usage) == 1))
>                 rtw_pci_aspm_set(rtwdev, enter);
>  }
>
> @@ -1658,6 +1661,9 @@ static int rtw_pci_napi_poll(struct napi_struct *napi, int budget)
>                                               priv);
>         int work_done = 0;
>
> +       if (rtwpci->rx_no_aspm)
> +               rtw_pci_link_ps(rtwdev, false);
> +
>         while (work_done < budget) {
>                 u32 work_done_once;
>
> @@ -1681,6 +1687,8 @@ static int rtw_pci_napi_poll(struct napi_struct *napi, int budget)
>                 if (rtw_pci_get_hw_rx_ring_nr(rtwdev, rtwpci))
>                         napi_schedule(napi);
>         }
> +       if (rtwpci->rx_no_aspm)
> +               rtw_pci_link_ps(rtwdev, true);
>
>         return work_done;
>  }
> @@ -1702,50 +1710,13 @@ static void rtw_pci_napi_deinit(struct rtw_dev *rtwdev)
>         netif_napi_del(&rtwpci->napi);
>  }
>
> -enum rtw88_quirk_dis_pci_caps {
> -       QUIRK_DIS_PCI_CAP_MSI,
> -       QUIRK_DIS_PCI_CAP_ASPM,
> -};
> -
> -static int disable_pci_caps(const struct dmi_system_id *dmi)
> -{
> -       uintptr_t dis_caps = (uintptr_t)dmi->driver_data;
> -
> -       if (dis_caps & BIT(QUIRK_DIS_PCI_CAP_MSI))
> -               rtw_disable_msi = true;
> -       if (dis_caps & BIT(QUIRK_DIS_PCI_CAP_ASPM))
> -               rtw_pci_disable_aspm = true;
> -
> -       return 1;
> -}
> -
> -static const struct dmi_system_id rtw88_pci_quirks[] = {
> -       {
> -               .callback = disable_pci_caps,
> -               .ident = "Protempo Ltd L116HTN6SPW",
> -               .matches = {
> -                       DMI_MATCH(DMI_SYS_VENDOR, "Protempo Ltd"),
> -                       DMI_MATCH(DMI_PRODUCT_NAME, "L116HTN6SPW"),
> -               },
> -               .driver_data = (void *)BIT(QUIRK_DIS_PCI_CAP_ASPM),
> -       },
> -       {
> -               .callback = disable_pci_caps,
> -               .ident = "HP HP Pavilion Laptop 14-ce0xxx",
> -               .matches = {
> -                       DMI_MATCH(DMI_SYS_VENDOR, "HP"),
> -                       DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Laptop 14-ce0xxx"),
> -               },
> -               .driver_data = (void *)BIT(QUIRK_DIS_PCI_CAP_ASPM),
> -       },
> -       {}
> -};
> -
>  int rtw_pci_probe(struct pci_dev *pdev,
>                   const struct pci_device_id *id)
>  {
> +       struct pci_dev *bridge = pci_upstream_bridge(pdev);
>         struct ieee80211_hw *hw;
>         struct rtw_dev *rtwdev;
> +       struct rtw_pci *rtwpci;
>         int drv_data_size;
>         int ret;
>
> @@ -1763,6 +1734,9 @@ int rtw_pci_probe(struct pci_dev *pdev,
>         rtwdev->hci.ops = &rtw_pci_ops;
>         rtwdev->hci.type = RTW_HCI_TYPE_PCIE;
>
> +       rtwpci = (struct rtw_pci *)rtwdev->priv;
> +       atomic_set(&rtwpci->link_usage, 1);
> +
>         ret = rtw_core_init(rtwdev);
>         if (ret)
>                 goto err_release_hw;
> @@ -1791,7 +1765,10 @@ int rtw_pci_probe(struct pci_dev *pdev,
>                 goto err_destroy_pci;
>         }
>
> -       dmi_check_system(rtw88_pci_quirks);
> +       /* Disable PCIe ASPM L1 while doing NAPI poll for 8821CE */
> +       if (pdev->device == 0xc821 && bridge->vendor == PCI_VENDOR_ID_INTEL)
> +               rtwpci->rx_no_aspm = true;
> +
>         rtw_pci_phy_cfg(rtwdev);
>
>         ret = rtw_register_hw(rtwdev, hw);
> diff --git a/drivers/net/wireless/realtek/rtw88/pci.h b/drivers/net/wireless/realtek/rtw88/pci.h
> index 66f78eb7757c5..0c37efd8c66fa 100644
> --- a/drivers/net/wireless/realtek/rtw88/pci.h
> +++ b/drivers/net/wireless/realtek/rtw88/pci.h
> @@ -223,6 +223,8 @@ struct rtw_pci {
>         struct rtw_pci_tx_ring tx_rings[RTK_MAX_TX_QUEUE_NUM];
>         struct rtw_pci_rx_ring rx_rings[RTK_MAX_RX_QUEUE_NUM];
>         u16 link_ctrl;
> +       atomic_t link_usage;
> +       bool rx_no_aspm;
>         DECLARE_BITMAP(flags, NUM_OF_RTW_PCI_FLAGS);
>
>         void __iomem *mmap;
> --
> 2.33.1
>
Ping-Ke Shih Dec. 15, 2021, 8:03 a.m. UTC | #2
> -----Original Message-----
> From: Jian-Hong Pan <jhp@endlessos.org>
> Sent: Wednesday, December 15, 2021 3:16 PM
> 
> Tried to apply this patch for testing.  But it seems conflicting to
> commit c81edb8dddaa "rtw88: add quirk to disable pci caps on HP 250 G7
> Notebook PC" in wireless-drivers-next repo.
> 

I fix the conflict manually, and the ASPM setting is expected.

--
Ping-Ke
Jian-Hong Pan Dec. 15, 2021, 10:06 a.m. UTC | #3
Pkshih <pkshih@realtek.com> 於 2021年12月15日 週三 下午4:03寫道:
>
>
> > -----Original Message-----
> > From: Jian-Hong Pan <jhp@endlessos.org>
> > Sent: Wednesday, December 15, 2021 3:16 PM
> >
> > Tried to apply this patch for testing.  But it seems conflicting to
> > commit c81edb8dddaa "rtw88: add quirk to disable pci caps on HP 250 G7
> > Notebook PC" in wireless-drivers-next repo.
> >
>
> I fix the conflict manually, and the ASPM setting is expected.

Yes!  Same from my side.

Jian-Hong Pan
Kai-Heng Feng Dec. 15, 2021, 11:45 a.m. UTC | #4
On Wed, Dec 15, 2021 at 6:07 PM Jian-Hong Pan <jhp@endlessos.org> wrote:
>
> Pkshih <pkshih@realtek.com> 於 2021年12月15日 週三 下午4:03寫道:
> >
> >
> > > -----Original Message-----
> > > From: Jian-Hong Pan <jhp@endlessos.org>
> > > Sent: Wednesday, December 15, 2021 3:16 PM
> > >
> > > Tried to apply this patch for testing.  But it seems conflicting to
> > > commit c81edb8dddaa "rtw88: add quirk to disable pci caps on HP 250 G7
> > > Notebook PC" in wireless-drivers-next repo.
> > >
> >
> > I fix the conflict manually, and the ASPM setting is expected.
>
> Yes!  Same from my side.

Sorry for that, I used the wrong tree.
Will send a new one.

Kai-Heng

>
> Jian-Hong Pan
diff mbox series

Patch

diff --git a/drivers/net/wireless/realtek/rtw88/pci.c b/drivers/net/wireless/realtek/rtw88/pci.c
index a7a6ebfaa203c..08cf66141889b 100644
--- a/drivers/net/wireless/realtek/rtw88/pci.c
+++ b/drivers/net/wireless/realtek/rtw88/pci.c
@@ -2,7 +2,6 @@ 
 /* Copyright(c) 2018-2019  Realtek Corporation
  */
 
-#include <linux/dmi.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include "main.h"
@@ -1409,7 +1408,11 @@  static void rtw_pci_link_ps(struct rtw_dev *rtwdev, bool enter)
 	 * throughput. This is probably because the ASPM behavior slightly
 	 * varies from different SOC.
 	 */
-	if (rtwpci->link_ctrl & PCI_EXP_LNKCTL_ASPM_L1)
+	if (!(rtwpci->link_ctrl & PCI_EXP_LNKCTL_ASPM_L1))
+		return;
+
+	if ((enter && atomic_dec_if_positive(&rtwpci->link_usage) == 0) ||
+	    (!enter && atomic_inc_return(&rtwpci->link_usage) == 1))
 		rtw_pci_aspm_set(rtwdev, enter);
 }
 
@@ -1658,6 +1661,9 @@  static int rtw_pci_napi_poll(struct napi_struct *napi, int budget)
 					      priv);
 	int work_done = 0;
 
+	if (rtwpci->rx_no_aspm)
+		rtw_pci_link_ps(rtwdev, false);
+
 	while (work_done < budget) {
 		u32 work_done_once;
 
@@ -1681,6 +1687,8 @@  static int rtw_pci_napi_poll(struct napi_struct *napi, int budget)
 		if (rtw_pci_get_hw_rx_ring_nr(rtwdev, rtwpci))
 			napi_schedule(napi);
 	}
+	if (rtwpci->rx_no_aspm)
+		rtw_pci_link_ps(rtwdev, true);
 
 	return work_done;
 }
@@ -1702,50 +1710,13 @@  static void rtw_pci_napi_deinit(struct rtw_dev *rtwdev)
 	netif_napi_del(&rtwpci->napi);
 }
 
-enum rtw88_quirk_dis_pci_caps {
-	QUIRK_DIS_PCI_CAP_MSI,
-	QUIRK_DIS_PCI_CAP_ASPM,
-};
-
-static int disable_pci_caps(const struct dmi_system_id *dmi)
-{
-	uintptr_t dis_caps = (uintptr_t)dmi->driver_data;
-
-	if (dis_caps & BIT(QUIRK_DIS_PCI_CAP_MSI))
-		rtw_disable_msi = true;
-	if (dis_caps & BIT(QUIRK_DIS_PCI_CAP_ASPM))
-		rtw_pci_disable_aspm = true;
-
-	return 1;
-}
-
-static const struct dmi_system_id rtw88_pci_quirks[] = {
-	{
-		.callback = disable_pci_caps,
-		.ident = "Protempo Ltd L116HTN6SPW",
-		.matches = {
-			DMI_MATCH(DMI_SYS_VENDOR, "Protempo Ltd"),
-			DMI_MATCH(DMI_PRODUCT_NAME, "L116HTN6SPW"),
-		},
-		.driver_data = (void *)BIT(QUIRK_DIS_PCI_CAP_ASPM),
-	},
-	{
-		.callback = disable_pci_caps,
-		.ident = "HP HP Pavilion Laptop 14-ce0xxx",
-		.matches = {
-			DMI_MATCH(DMI_SYS_VENDOR, "HP"),
-			DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Laptop 14-ce0xxx"),
-		},
-		.driver_data = (void *)BIT(QUIRK_DIS_PCI_CAP_ASPM),
-	},
-	{}
-};
-
 int rtw_pci_probe(struct pci_dev *pdev,
 		  const struct pci_device_id *id)
 {
+	struct pci_dev *bridge = pci_upstream_bridge(pdev);
 	struct ieee80211_hw *hw;
 	struct rtw_dev *rtwdev;
+	struct rtw_pci *rtwpci;
 	int drv_data_size;
 	int ret;
 
@@ -1763,6 +1734,9 @@  int rtw_pci_probe(struct pci_dev *pdev,
 	rtwdev->hci.ops = &rtw_pci_ops;
 	rtwdev->hci.type = RTW_HCI_TYPE_PCIE;
 
+	rtwpci = (struct rtw_pci *)rtwdev->priv;
+	atomic_set(&rtwpci->link_usage, 1);
+
 	ret = rtw_core_init(rtwdev);
 	if (ret)
 		goto err_release_hw;
@@ -1791,7 +1765,10 @@  int rtw_pci_probe(struct pci_dev *pdev,
 		goto err_destroy_pci;
 	}
 
-	dmi_check_system(rtw88_pci_quirks);
+	/* Disable PCIe ASPM L1 while doing NAPI poll for 8821CE */
+	if (pdev->device == 0xc821 && bridge->vendor == PCI_VENDOR_ID_INTEL)
+		rtwpci->rx_no_aspm = true;
+
 	rtw_pci_phy_cfg(rtwdev);
 
 	ret = rtw_register_hw(rtwdev, hw);
diff --git a/drivers/net/wireless/realtek/rtw88/pci.h b/drivers/net/wireless/realtek/rtw88/pci.h
index 66f78eb7757c5..0c37efd8c66fa 100644
--- a/drivers/net/wireless/realtek/rtw88/pci.h
+++ b/drivers/net/wireless/realtek/rtw88/pci.h
@@ -223,6 +223,8 @@  struct rtw_pci {
 	struct rtw_pci_tx_ring tx_rings[RTK_MAX_TX_QUEUE_NUM];
 	struct rtw_pci_rx_ring rx_rings[RTK_MAX_RX_QUEUE_NUM];
 	u16 link_ctrl;
+	atomic_t link_usage;
+	bool rx_no_aspm;
 	DECLARE_BITMAP(flags, NUM_OF_RTW_PCI_FLAGS);
 
 	void __iomem *mmap;