[PATCH net 0/2] r8169: revert two changes that caused regressions

[PATCH net 0/2] r8169: revert two changes that caused regressions

[Heiner Kallweit]

This reverts two changes that caused regressions.

Heiner Kallweit (2):
  r8169: revert 2ab19de62d67 ("r8169: remove ASPM restrictions now that
    ASPM is disabled during NAPI poll")
  Revert "r8169: disable ASPM during NAPI poll"

 drivers/net/ethernet/realtek/r8169_main.c | 38 ++++++++++++++++-------
 1 file changed, 27 insertions(+), 11 deletions(-)

-- 
2.41.0

[PATCH net 1/2] r8169: revert 2ab19de62d67 ("r8169: remove ASPM restrictions now that ASPM is disabled during NAPI poll")

[Heiner Kallweit]

There have been reports that on a number of systems this change breaks
network connectivity. Therefore effectively revert it. Mainly affected
seem to be systems where BIOS denies ASPM access to OS.
Due to later changes we can't do a direct revert.

Fixes: 2ab19de62d67 ("r8169: remove ASPM restrictions now that ASPM is disabled during NAPI poll")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/netdev/e47bac0d-e802-65e1-b311-6acb26d5cf10@freenet.de/T/
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217596
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 27 ++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index fce4a2b90..8a8b7d8a5 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -623,6 +623,7 @@ struct rtl8169_private {
 	int cfg9346_usage_count;
 
 	unsigned supports_gmii:1;
+	unsigned aspm_manageable:1;
 	dma_addr_t counters_phys_addr;
 	struct rtl8169_counters *counters;
 	struct rtl8169_tc_offsets tc_offset;
@@ -2746,7 +2747,8 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
 	if (tp->mac_version < RTL_GIGA_MAC_VER_32)
 		return;
 
-	if (enable) {
+	/* Don't enable ASPM in the chip if OS can't control ASPM */
+	if (enable && tp->aspm_manageable) {
 		/* On these chip versions ASPM can even harm
 		 * bus communication of other PCI devices.
 		 */
@@ -5165,6 +5167,16 @@ static void rtl_init_mac_address(struct rtl8169_private *tp)
 	rtl_rar_set(tp, mac_addr);
 }
 
+/* register is set if system vendor successfully tested ASPM 1.2 */
+static bool rtl_aspm_is_safe(struct rtl8169_private *tp)
+{
+	if (tp->mac_version >= RTL_GIGA_MAC_VER_61 &&
+	    r8168_mac_ocp_read(tp, 0xc0b2) & 0xf)
+		return true;
+
+	return false;
+}
+
 static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	struct rtl8169_private *tp;
@@ -5234,6 +5246,19 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 				     xid);
 	tp->mac_version = chipset;
 
+	/* Disable ASPM L1 as that cause random device stop working
+	 * problems as well as full system hangs for some PCIe devices users.
+	 * Chips from RTL8168h partially have issues with L1.2, but seem
+	 * to work fine with L1 and L1.1.
+	 */
+	if (rtl_aspm_is_safe(tp))
+		rc = 0;
+	else if (tp->mac_version >= RTL_GIGA_MAC_VER_46)
+		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1_2);
+	else
+		rc = pci_disable_link_state(pdev, PCIE_LINK_STATE_L1);
+	tp->aspm_manageable = !rc;
+
 	tp->dash_type = rtl_check_dash(tp);
 
 	tp->cp_cmd = RTL_R16(tp, CPlusCmd) & CPCMD_MASK;
-- 
2.41.0

[PATCH net 2/2] Revert "r8169: disable ASPM during NAPI poll"

[Heiner Kallweit]

This reverts commit e1ed3e4d91112027b90c7ee61479141b3f948e6a.

Turned out the change causes a performance regression.

Link: https://lore.kernel.org/netdev/20230713124914.GA12924@green245/T/
Cc: stable@vger.kernel.org
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 8a8b7d8a5..5eb50b265 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -4523,10 +4523,6 @@ static irqreturn_t rtl8169_interrupt(int irq, void *dev_instance)
 	}
 
 	if (napi_schedule_prep(&tp->napi)) {
-		rtl_unlock_config_regs(tp);
-		rtl_hw_aspm_clkreq_enable(tp, false);
-		rtl_lock_config_regs(tp);
-
 		rtl_irq_disable(tp);
 		__napi_schedule(&tp->napi);
 	}
@@ -4586,14 +4582,9 @@ static int rtl8169_poll(struct napi_struct *napi, int budget)
 
 	work_done = rtl_rx(dev, tp, budget);
 
-	if (work_done < budget && napi_complete_done(napi, work_done)) {
+	if (work_done < budget && napi_complete_done(napi, work_done))
 		rtl_irq_enable(tp);
 
-		rtl_unlock_config_regs(tp);
-		rtl_hw_aspm_clkreq_enable(tp, true);
-		rtl_lock_config_regs(tp);
-	}
-
 	return work_done;
 }
 
-- 
2.41.0

Re: [PATCH net 0/2] r8169: revert two changes that caused regressions

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Tue, 18 Jul 2023 13:07:53 +0200 you wrote:
> This reverts two changes that caused regressions.
> 
> Heiner Kallweit (2):
>   r8169: revert 2ab19de62d67 ("r8169: remove ASPM restrictions now that
>     ASPM is disabled during NAPI poll")
>   Revert "r8169: disable ASPM during NAPI poll"
> 
> [...]

Here is the summary with links:
  - [net,1/2] r8169: revert 2ab19de62d67 ("r8169: remove ASPM restrictions now that ASPM is disabled during NAPI poll")
    https://git.kernel.org/netdev/net/c/cf2ffdea0839
  - [net,2/2] Revert "r8169: disable ASPM during NAPI poll"
    https://git.kernel.org/netdev/net/c/e31a9fedc7d8

You are awesome, thank you!
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