From d76ca16ab79612b43eb1ef830a296656f0d75485 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Fri, 29 Jul 2011 15:59:08 +0200 Subject: [PATCH] ath9k: skip ->config_pci_powersave() if PCIe port has ASPM disabled We receive many bug reports about system hang during suspend/resume when ath9k driver is in use. Adrian Chadd remarked that this problem happens on systems that have ASPM disabled. To do not hit the bug, skip doing ->config_pci_powersave magic if PCIe downstream port device, which ath9k device is connected to, has ASPM disabled. Bug was introduced by: commit 43acc41b26ec6068b6f3cbf11c3e741628e49aa1 Author: Vivek Natarajan Date: Mon Apr 5 14:48:04 2010 +0530 ath9k: Add support for newer AR9285 chipsets. Patch should address: https://bugzilla.kernel.org/show_bug.cgi?id=37462 https://bugzilla.kernel.org/show_bug.cgi?id=37082 https://bugzilla.redhat.com/show_bug.cgi?id=697157 however I did not receive confirmation about that, except from Camilo Mesias, whose system stops hang regularly with this patch (but still hangs from time to time, but this is probably some other bug). Tested-by: Camilo Mesias Cc: stable@kernel.org # 2.6.35+ Signed-off-by: Stanislaw Gruszka Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/ar9002_hw.c | 6 +---- drivers/net/wireless/ath/ath9k/ar9003_hw.c | 6 +---- drivers/net/wireless/ath/ath9k/hw.c | 11 +++++++-- drivers/net/wireless/ath/ath9k/hw.h | 3 ++- drivers/net/wireless/ath/ath9k/pci.c | 27 ++++++++++++++++++++++ 5 files changed, 40 insertions(+), 13 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/ar9002_hw.c b/drivers/net/wireless/ath/ath9k/ar9002_hw.c index 9ff7c30573b8d..44d9d8d56490c 100644 --- a/drivers/net/wireless/ath/ath9k/ar9002_hw.c +++ b/drivers/net/wireless/ath/ath9k/ar9002_hw.c @@ -309,11 +309,7 @@ static void ar9002_hw_configpcipowersave(struct ath_hw *ah, u8 i; u32 val; - if (ah->is_pciexpress != true) - return; - - /* Do not touch SerDes registers */ - if (ah->config.pcie_powersave_enable == 2) + if (ah->is_pciexpress != true || ah->aspm_enabled != true) return; /* Nothing to do on restore for 11N */ diff --git a/drivers/net/wireless/ath/ath9k/ar9003_hw.c b/drivers/net/wireless/ath/ath9k/ar9003_hw.c index 8efdec247c022..ad2bb2bf4e8a8 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_hw.c +++ b/drivers/net/wireless/ath/ath9k/ar9003_hw.c @@ -519,11 +519,7 @@ static void ar9003_hw_configpcipowersave(struct ath_hw *ah, int restore, int power_off) { - if (ah->is_pciexpress != true) - return; - - /* Do not touch SerDes registers */ - if (ah->config.pcie_powersave_enable == 2) + if (ah->is_pciexpress != true || ah->aspm_enabled != true) return; /* Nothing to do on restore for 11N */ diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index 8006ce0c73577..8dcefe74f4c39 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -318,6 +318,14 @@ static void ath9k_hw_disablepcie(struct ath_hw *ah) REG_WRITE(ah, AR_PCIE_SERDES2, 0x00000000); } +static void ath9k_hw_aspm_init(struct ath_hw *ah) +{ + struct ath_common *common = ath9k_hw_common(ah); + + if (common->bus_ops->aspm_init) + common->bus_ops->aspm_init(common); +} + /* This should work for all families including legacy */ static bool ath9k_hw_chip_test(struct ath_hw *ah) { @@ -378,7 +386,6 @@ static void ath9k_hw_init_config(struct ath_hw *ah) ah->config.additional_swba_backoff = 0; ah->config.ack_6mb = 0x0; ah->config.cwm_ignore_extcca = 0; - ah->config.pcie_powersave_enable = 0; ah->config.pcie_clock_req = 0; ah->config.pcie_waen = 0; ah->config.analog_shiftreg = 1; @@ -598,7 +605,7 @@ static int __ath9k_hw_init(struct ath_hw *ah) if (ah->is_pciexpress) - ath9k_hw_configpcipowersave(ah, 0, 0); + ath9k_hw_aspm_init(ah); else ath9k_hw_disablepcie(ah); diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h index 6acd0f975ae1e..c79889036ec40 100644 --- a/drivers/net/wireless/ath/ath9k/hw.h +++ b/drivers/net/wireless/ath/ath9k/hw.h @@ -219,7 +219,6 @@ struct ath9k_ops_config { int additional_swba_backoff; int ack_6mb; u32 cwm_ignore_extcca; - u8 pcie_powersave_enable; bool pcieSerDesWrite; u8 pcie_clock_req; u32 pcie_waen; @@ -673,6 +672,7 @@ struct ath_hw { bool sw_mgmt_crypto; bool is_pciexpress; + bool aspm_enabled; bool is_monitoring; bool need_an_top2_fixup; u16 tx_trig_level; @@ -874,6 +874,7 @@ struct ath_bus_ops { bool (*eeprom_read)(struct ath_common *common, u32 off, u16 *data); void (*bt_coex_prep)(struct ath_common *common); void (*extn_synch_en)(struct ath_common *common); + void (*aspm_init)(struct ath_common *common); }; static inline struct ath_common *ath9k_hw_common(struct ath_hw *ah) diff --git a/drivers/net/wireless/ath/ath9k/pci.c b/drivers/net/wireless/ath/ath9k/pci.c index 3bad0b2cf9a3f..be4ea13298134 100644 --- a/drivers/net/wireless/ath/ath9k/pci.c +++ b/drivers/net/wireless/ath/ath9k/pci.c @@ -16,6 +16,7 @@ #include #include +#include #include #include "ath9k.h" @@ -115,12 +116,38 @@ static void ath_pci_extn_synch_enable(struct ath_common *common) pci_write_config_byte(pdev, sc->sc_ah->caps.pcie_lcr_offset, lnkctl); } +static void ath_pci_aspm_init(struct ath_common *common) +{ + struct ath_softc *sc = (struct ath_softc *) common->priv; + struct ath_hw *ah = sc->sc_ah; + struct pci_dev *pdev = to_pci_dev(sc->dev); + struct pci_dev *parent; + int pos; + u8 aspm; + + if (!pci_is_pcie(pdev)) + return; + + parent = pdev->bus->self; + if (WARN_ON(!parent)) + return; + + pos = pci_pcie_cap(parent); + pci_read_config_byte(parent, pos + PCI_EXP_LNKCTL, &aspm); + if (aspm & (PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1)) { + ah->aspm_enabled = true; + /* Initialize PCIe PM and SERDES registers. */ + ath9k_hw_configpcipowersave(ah, 0, 0); + } +} + static const struct ath_bus_ops ath_pci_bus_ops = { .ath_bus_type = ATH_PCI, .read_cachesize = ath_pci_read_cachesize, .eeprom_read = ath_pci_eeprom_read, .bt_coex_prep = ath_pci_bt_coex_prep, .extn_synch_en = ath_pci_extn_synch_enable, + .aspm_init = ath_pci_aspm_init, }; static int ath_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) -- 2.39.5