Merge branch 'r8169-revert-two-changes-that-caused-regressions'

Heiner Kallweit says:

====================
r8169: revert two changes that caused regressions

This reverts two changes that caused regressions.
====================

Link: https://lore.kernel.org/r/ddadceae-19c9-81b8-47b5-a4ff85e2563a@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: kuba-moo

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.
 		 */
@@ -4521,10 +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);
 	}
@@ -4584,14 +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;
 }
 
@@ -5165,6 +5158,16 @@ 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 +5237,19 @@ 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;