diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index 394f99852e6d..a4817a841fae 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -110,6 +110,7 @@ struct controller { struct timer_list poll_timer; int cmd_busy; unsigned int no_cmd_complete:1; + unsigned int link_active_reporting:1; }; #define INT_BUTTON_IGNORE 0 diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c index cce6e5f659e8..d6c5eb297753 100644 --- a/drivers/pci/hotplug/pciehp_ctrl.c +++ b/drivers/pci/hotplug/pciehp_ctrl.c @@ -226,9 +226,6 @@ static int board_added(struct slot *p_slot) if (PWR_LED(ctrl)) p_slot->hpc_ops->green_led_blink(p_slot); - /* Wait for ~1 second */ - msleep(1000); - /* Check link training status */ retval = p_slot->hpc_ops->check_lnk_status(ctrl); if (retval) { diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 4b921226f888..58c72d2cc217 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -125,6 +125,7 @@ static inline int pciehp_writel(struct controller *ctrl, int reg, u32 value) /* Field definitions in Link Capabilities Register */ #define MAX_LNK_SPEED 0x000F #define MAX_LNK_WIDTH 0x03F0 +#define LINK_ACTIVE_REPORTING 0x00100000 /* Link Width Encoding */ #define LNK_X1 0x01 @@ -141,6 +142,7 @@ static inline int pciehp_writel(struct controller *ctrl, int reg, u32 value) #define LNK_TRN_ERR 0x0400 #define LNK_TRN 0x0800 #define SLOT_CLK_CONF 0x1000 +#define LINK_ACTIVE 0x2000 /* Field definitions in Slot Capabilities Register */ #define ATTN_BUTTN_PRSN 0x00000001 @@ -368,11 +370,52 @@ static int pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask) return retval; } +static inline int check_link_active(struct controller *ctrl) +{ + u16 link_status; + + if (pciehp_readw(ctrl, LNKSTATUS, &link_status)) + return 0; + return !!(link_status & LINK_ACTIVE); +} + +static void pcie_wait_link_active(struct controller *ctrl) +{ + int timeout = 1000; + + if (check_link_active(ctrl)) + return; + while (timeout > 0) { + msleep(10); + timeout -= 10; + if (check_link_active(ctrl)) + return; + } + ctrl_dbg(ctrl, "Data Link Layer Link Active not set in 1000 msec\n"); +} + static int hpc_check_lnk_status(struct controller *ctrl) { u16 lnk_status; int retval = 0; + /* + * Data Link Layer Link Active Reporting must be capable for + * hot-plug capable downstream port. But old controller might + * not implement it. In this case, we wait for 1000 ms. + */ + if (ctrl->link_active_reporting){ + /* Wait for Data Link Layer Link Active bit to be set */ + pcie_wait_link_active(ctrl); + /* + * We must wait for 100 ms after the Data Link Layer + * Link Active bit reads 1b before initiating a + * configuration access to the hot added device. + */ + msleep(100); + } else + msleep(1000); + retval = pciehp_readw(ctrl, LNKSTATUS, &lnk_status); if (retval) { ctrl_err(ctrl, "%s: Cannot read LNKSTATUS register\n", @@ -1131,7 +1174,7 @@ static inline void dbg_ctrl(struct controller *ctrl) struct controller *pcie_init(struct pcie_device *dev) { struct controller *ctrl; - u32 slot_cap; + u32 slot_cap, link_cap; struct pci_dev *pdev = dev->port; ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); @@ -1173,6 +1216,16 @@ struct controller *pcie_init(struct pcie_device *dev) !(POWER_CTRL(ctrl) | ATTN_LED(ctrl) | PWR_LED(ctrl) | EMI(ctrl))) ctrl->no_cmd_complete = 1; + /* Check if Data Link Layer Link Active Reporting is implemented */ + if (pciehp_readl(ctrl, LNKCAP, &link_cap)) { + ctrl_err(ctrl, "%s: Cannot read LNKCAP register\n", __func__); + goto abort_ctrl; + } + if (link_cap & LINK_ACTIVE_REPORTING) { + ctrl_dbg(ctrl, "Link Active Reporting supported\n"); + ctrl->link_active_reporting = 1; + } + /* Clear all remaining event bits in Slot Status register */ if (pciehp_writew(ctrl, SLOTSTATUS, 0x1f)) goto abort_ctrl;