From 337891ffea7c9e65b456663e080028371401f3be Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pali=20Roh=C3=A1r?= Date: Wed, 31 Mar 2021 15:12:50 +0200 Subject: [PATCH 43/53] PCI: pciehp: Enable DLLSC interrupt only if supported MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Don't enable Data Link Layer State Changed interrupt if it isn't supported. Data Link Layer Link Active Reporting Capable bit in Link Capabilities register indicates if Data Link Layer State Changed Enable is supported. Signed-off-by: Pali Rohár Signed-off-by: Marek Behún --- drivers/pci/hotplug/pciehp_hpc.c | 32 ++++++++++++++++++++++++-------- drivers/pci/hotplug/pnv_php.c | 13 +++++++++---- 2 files changed, 33 insertions(+), 12 deletions(-) diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 040ae076ec0e..ef807c79b1b1 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -788,6 +788,7 @@ static int pciehp_poll(void *data) static void pcie_enable_notification(struct controller *ctrl) { u16 cmd, mask; + u32 link_cap; /* * TBD: Power fault detected software notification support. @@ -800,12 +801,17 @@ static void pcie_enable_notification(struct controller *ctrl) * next power fault detected interrupt was notified again. */ + pcie_capability_read_dword(ctrl_dev(ctrl), PCI_EXP_LNKCAP, &link_cap); + /* - * Always enable link events: thus link-up and link-down shall - * always be treated as hotplug and unplug respectively. Enable - * presence detect only if Attention Button is not present. - */ - cmd = PCI_EXP_SLTCTL_DLLSCE; + * Enable link events if their support is indicated in Link Capability + * register: thus link-up and link-down shall always be treated as + * hotplug and unplug respectively. Enable presence detect only if + * Attention Button is not present. + */ + cmd = 0; + if (link_cap & PCI_EXP_LNKCAP_DLLLARC) + cmd |= PCI_EXP_SLTCTL_DLLSCE; if (ATTN_BUTTN(ctrl)) cmd |= PCI_EXP_SLTCTL_ABPE; else @@ -845,8 +851,13 @@ void pcie_clear_hotplug_events(struct controller *ctrl) void pcie_enable_interrupt(struct controller *ctrl) { u16 mask; + u32 link_cap; - mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE; + pcie_capability_read_dword(ctrl_dev(ctrl), PCI_EXP_LNKCAP, &link_cap); + + mask = PCI_EXP_SLTCTL_HPIE; + if (link_cap & PCI_EXP_LNKCAP_DLLLARC) + mask |= PCI_EXP_SLTCTL_DLLSCE; pcie_write_cmd(ctrl, mask, mask); } @@ -904,19 +915,24 @@ int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, bool probe) struct controller *ctrl = to_ctrl(hotplug_slot); struct pci_dev *pdev = ctrl_dev(ctrl); u16 stat_mask = 0, ctrl_mask = 0; + u32 link_cap; int rc; if (probe) return 0; + pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap); + down_write_nested(&ctrl->reset_lock, ctrl->depth); if (!ATTN_BUTTN(ctrl)) { ctrl_mask |= PCI_EXP_SLTCTL_PDCE; stat_mask |= PCI_EXP_SLTSTA_PDC; } - ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE; - stat_mask |= PCI_EXP_SLTSTA_DLLSC; + if (link_cap & PCI_EXP_LNKCAP_DLLLARC) { + ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE; + stat_mask |= PCI_EXP_SLTSTA_DLLSC; + } pcie_write_cmd(ctrl, 0, ctrl_mask); ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c index 881d420637bf..5c700d3a9009 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -840,6 +840,7 @@ static void pnv_php_init_irq(struct pnv_php_slot *php_slot, int irq) { struct pci_dev *pdev = php_slot->pdev; u32 broken_pdc = 0; + u32 link_cap; u16 sts, ctrl; int ret; @@ -874,17 +875,21 @@ static void pnv_php_init_irq(struct pnv_php_slot *php_slot, int irq) return; } + pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap); + /* Enable the interrupts */ pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl); if (php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) { ctrl &= ~PCI_EXP_SLTCTL_PDCE; - ctrl |= (PCI_EXP_SLTCTL_HPIE | - PCI_EXP_SLTCTL_DLLSCE); + ctrl |= PCI_EXP_SLTCTL_HPIE; } else { ctrl |= (PCI_EXP_SLTCTL_HPIE | - PCI_EXP_SLTCTL_PDCE | - PCI_EXP_SLTCTL_DLLSCE); + PCI_EXP_SLTCTL_PDCE); } + if (link_cap & PCI_EXP_LNKCAP_DLLLARC) + ctrl |= PCI_EXP_SLTCTL_DLLSCE; + else + ctrl &= ~PCI_EXP_SLTCTL_DLLSCE; pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, ctrl); /* The interrupt is initialized successfully when @irq is valid */ -- 2.37.3