From 0f61ab172d49b2e419208d4d96fca560a98b9915 Mon Sep 17 00:00:00 2001 From: Shaun Ruffell Date: Wed, 21 Mar 2012 16:34:02 +0000 Subject: [PATCH] wct4xxp: Add compile-time option to disable ASPM for PCIe devices. Certain BIOSes appear to enable ASPM even though it is not fully supported by the platform. Also, since the PCIe links for TDM cards are always in use it does not make sense to allow them to transition to the disabled state. Just turn off power management on the PCIe links completely. For more information see http://lwn.net/Articles/449448/. Internal-Issue-ID: DAHLIN-283 Signed-off-by: Shaun Ruffell git-svn-id: http://svn.asterisk.org/svn/dahdi/linux/trunk@10558 a0bf4364-ded3-4de4-8d8a-66a801d63aff --- drivers/dahdi/wct4xxp/base.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/dahdi/wct4xxp/base.c b/drivers/dahdi/wct4xxp/base.c index 8a9edc3..27fbc6a 100644 --- a/drivers/dahdi/wct4xxp/base.c +++ b/drivers/dahdi/wct4xxp/base.c @@ -169,6 +169,15 @@ static inline int t4_queue_work(struct workqueue_struct *wq, struct work_struct /* #define CONFIG_FORCE_EXTENDED_RESET */ /* #define CONFIG_NOEXTENDED_RESET */ +/* + * Uncomment the following definition in order to disable Active-State Power + * Management on the PCIe bridge for PCIe cards. This has been known to work + * around issues where the BIOS enables it on the cards even though the + * platform does not support it. + * + */ +/* #define CONFIG_WCT4XXP_DISABLE_ASPM */ + #if defined(CONFIG_FORCE_EXTENDED_RESET) && defined(CONFIG_NOEXTENDED_RESET) #error "You cannot define both CONFIG_FORCE_EXTENDED_RESET and " \ "CONFIG_NOEXTENDED_RESET." @@ -374,6 +383,11 @@ struct t4 { struct spi_state st; }; +static inline bool is_pcie(const struct t4 *wc) +{ + return (wc->devtype->flags & FLAG_EXPRESS) > 0; +} + static inline bool has_e1_span(const struct t4 *wc) { return (wc->t1e1) != 0; @@ -5043,6 +5057,13 @@ t4_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) spin_lock_init(&wc->reglock); wc->devtype = (const struct devtype *)(ent->driver_data); +#ifdef CONFIG_WCT4XXP_DISABLE_ASPM + if (is_pcie(wc)) { + pci_disable_link_state(pdev->bus->self, PCIE_LINK_STATE_L0S | + PCIE_LINK_STATE_L1 | PCIE_LINK_STATE_CLKPM); + }; +#endif + if (is_octal(wc)) wc->numspans = 8; else if (wc->devtype->flags & FLAG_2PORT)