From f37f05503575c59020dacd36e999f4e8b3dbc115 Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Sun, 27 Oct 2019 20:53:08 +0100 Subject: [PATCH] mt76: mt76x2e: disable pcie_aspm by default On same device (e.g. U7612E-H1) PCIE_ASPM causes continuous mcu hangs and instability. Since mt76x2 series does not manage PCIE PS states, first we try to disable ASPM using pci_disable_link_state. If it fails, we will disable PCIE PS configuring PCI registers. This patch has been successfully tested on U7612E-H1 mini-pice card Tested-by: Oleksandr Natalenko Signed-off-by: Felix Fietkau Signed-off-by: Lorenzo Bianconi Signed-off-by: Kalle Valo --- drivers/net/wireless/mediatek/mt76/Makefile | 2 + drivers/net/wireless/mediatek/mt76/mt76.h | 1 + .../net/wireless/mediatek/mt76/mt76x2/pci.c | 2 + drivers/net/wireless/mediatek/mt76/pci.c | 46 +++++++++++++++++++ 4 files changed, 51 insertions(+) create mode 100644 drivers/net/wireless/mediatek/mt76/pci.c diff --git a/drivers/net/wireless/mediatek/mt76/Makefile b/drivers/net/wireless/mediatek/mt76/Makefile index 4d03596e891f..d7a1ddc9e407 100644 --- a/drivers/net/wireless/mediatek/mt76/Makefile +++ b/drivers/net/wireless/mediatek/mt76/Makefile @@ -8,6 +8,8 @@ mt76-y := \ mmio.o util.o trace.o dma.o mac80211.o debugfs.o eeprom.o \ tx.o agg-rx.o mcu.o +mt76-$(CONFIG_PCI) += pci.o + mt76-usb-y := usb.o usb_trace.o CFLAGS_trace.o := -I$(src) diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h index 570c159515a0..dc468ed9434a 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76.h +++ b/drivers/net/wireless/mediatek/mt76/mt76.h @@ -578,6 +578,7 @@ bool __mt76_poll_msec(struct mt76_dev *dev, u32 offset, u32 mask, u32 val, #define mt76_poll_msec(dev, ...) __mt76_poll_msec(&((dev)->mt76), __VA_ARGS__) void mt76_mmio_init(struct mt76_dev *dev, void __iomem *regs); +void mt76_pci_disable_aspm(struct pci_dev *pdev); static inline u16 mt76_chip(struct mt76_dev *dev) { diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2/pci.c b/drivers/net/wireless/mediatek/mt76/mt76x2/pci.c index 73c3104f8858..cf611d1b817c 100644 --- a/drivers/net/wireless/mediatek/mt76/mt76x2/pci.c +++ b/drivers/net/wireless/mediatek/mt76/mt76x2/pci.c @@ -81,6 +81,8 @@ mt76pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) /* RG_SSUSB_CDR_BR_PE1D = 0x3 */ mt76_rmw_field(dev, 0x15c58, 0x3 << 6, 0x3); + mt76_pci_disable_aspm(pdev); + return 0; error: diff --git a/drivers/net/wireless/mediatek/mt76/pci.c b/drivers/net/wireless/mediatek/mt76/pci.c new file mode 100644 index 000000000000..04c5a692bc85 --- /dev/null +++ b/drivers/net/wireless/mediatek/mt76/pci.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: ISC +/* + * Copyright (C) 2019 Lorenzo Bianconi + */ + +#include + +void mt76_pci_disable_aspm(struct pci_dev *pdev) +{ + struct pci_dev *parent = pdev->bus->self; + u16 aspm_conf, parent_aspm_conf = 0; + + pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &aspm_conf); + aspm_conf &= PCI_EXP_LNKCTL_ASPMC; + if (parent) { + pcie_capability_read_word(parent, PCI_EXP_LNKCTL, + &parent_aspm_conf); + parent_aspm_conf &= PCI_EXP_LNKCTL_ASPMC; + } + + if (!aspm_conf && (!parent || !parent_aspm_conf)) { + /* aspm already disabled */ + return; + } + + dev_info(&pdev->dev, "disabling ASPM %s %s\n", + (aspm_conf & PCI_EXP_LNKCTL_ASPM_L0S) ? "L0s" : "", + (aspm_conf & PCI_EXP_LNKCTL_ASPM_L1) ? "L1" : ""); + + if (IS_ENABLED(CONFIG_PCIEASPM)) { + int err; + + err = pci_disable_link_state(pdev, aspm_conf); + if (!err) + return; + } + + /* both device and parent should have the same ASPM setting. + * disable ASPM in downstream component first and then upstream. + */ + pcie_capability_clear_word(pdev, PCI_EXP_LNKCTL, aspm_conf); + if (parent) + pcie_capability_clear_word(parent, PCI_EXP_LNKCTL, + aspm_conf); +} +EXPORT_SYMBOL_GPL(mt76_pci_disable_aspm); -- GitLab