From: Luca Coelho <luciano.coelho@xxxxxxxxx>
If we fail to to grab NIC access because the device is not responding
(i.e. CSR_GP_CNTRL returns 0xFFFFFFFF), remove the device from the PCI
bus, to avoid any further damage, and to let the user space rescan.
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
---
drivers/net/wireless/intel/iwlwifi/iwl-drv.c | 6 ++
.../wireless/intel/iwlwifi/iwl-modparams.h | 2 +
.../wireless/intel/iwlwifi/pcie/internal.h | 5 ++
.../net/wireless/intel/iwlwifi/pcie/trans.c | 74 ++++++++++++++++++-
4 files changed, 84 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
index 4f451a6f20b9..c59ce4f8a5ed 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
@@ -1850,3 +1850,9 @@ MODULE_PARM_DESC(d0i3_timeout, "Timeout to D0i3 entry when idle (ms)");
module_param_named(disable_11ac, iwlwifi_mod_params.disable_11ac, bool, 0444);
MODULE_PARM_DESC(disable_11ac, "Disable VHT capabilities (default: false)");
+
+module_param_named(remove_when_gone,
+ iwlwifi_mod_params.remove_when_gone, bool,
+ 0444);
+MODULE_PARM_DESC(remove_when_gone,
+ "Remove dev from PCIe bus if it is deemed inaccessible (default: false)");
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h b/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h
index a41c46e63eb1..a7dd8a8cddf9 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-modparams.h
@@ -122,6 +122,7 @@ enum iwl_uapsd_disable {
* @lar_disable: disable LAR (regulatory), default = 0
* @fw_monitor: allow to use firmware monitor
* @disable_11ac: disable VHT capabilities, default = false.
+ * @remove_when_gone: remove an inaccessible device from the PCIe bus.
*/
struct iwl_mod_params {
int swcrypto;
@@ -143,6 +144,7 @@ struct iwl_mod_params {
bool lar_disable;
bool fw_monitor;
bool disable_11ac;
+ bool remove_when_gone;
};
#endif /* #__iwl_modparams_h__ */
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
index cda66340d357..45ea32796cda 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
@@ -383,6 +383,8 @@ struct iwl_self_init_dram {
* @hw_init_mask: initial unmasked hw causes
* @fh_mask: current unmasked fh causes
* @hw_mask: current unmasked hw causes
+ * @in_rescan: true if we have triggered a device rescan
+ * @scheduled_for_removal: true if we have scheduled a device removal
*/
struct iwl_trans_pcie {
struct iwl_rxq *rxq;
@@ -464,6 +466,9 @@ struct iwl_trans_pcie {
u32 fh_mask;
u32 hw_mask;
cpumask_t affinity_mask[IWL_MAX_RX_HW_QUEUES];
+ u16 tx_cmd_queue_size;
+ bool in_rescan;
+ bool scheduled_for_removal;
};
static inline struct iwl_trans_pcie *
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
index 623476603cd4..6e9a9ecfb11c 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
@@ -75,6 +75,7 @@
#include <linux/gfp.h>
#include <linux/vmalloc.h>
#include <linux/pm_runtime.h>
+#include <linux/module.h>
#include "iwl-drv.h"
#include "iwl-trans.h"
@@ -1935,6 +1936,29 @@ static void iwl_trans_pcie_set_pmi(struct iwl_trans *trans, bool state)
clear_bit(STATUS_TPOWER_PMI, &trans->status);
}
+struct iwl_trans_pcie_removal {
+ struct pci_dev *pdev;
+ struct work_struct work;
+};
+
+static void iwl_trans_pcie_removal_wk(struct work_struct *wk)
+{
+ struct iwl_trans_pcie_removal *removal =
+ container_of(wk, struct iwl_trans_pcie_removal, work);
+ struct pci_dev *pdev = removal->pdev;
+ char *prop[] = {"EVENT=INACCESSIBLE", NULL};
+
+ dev_err(&pdev->dev, "Device gone - attempting removal\n");
+ kobject_uevent_env(&pdev->dev.kobj, KOBJ_CHANGE, prop);
+ pci_lock_rescan_remove();
+ pci_dev_put(pdev);
+ pci_stop_and_remove_bus_device(pdev);
+ pci_unlock_rescan_remove();
+
+ kfree(removal);
+ module_put(THIS_MODULE);
+}
+
static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans,
unsigned long *flags)
{
@@ -1977,11 +2001,55 @@ static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans,
(BIT(trans->cfg->csr->flag_mac_clock_ready) |
CSR_GP_CNTRL_REG_FLAG_GOING_TO_SLEEP), 15000);
if (unlikely(ret < 0)) {
- iwl_trans_pcie_dump_regs(trans);
- iwl_write32(trans, CSR_RESET, CSR_RESET_REG_FLAG_FORCE_NMI);
+ u32 cntrl = iwl_read32(trans, CSR_GP_CNTRL);
+
WARN_ONCE(1,
"Timeout waiting for hardware access (CSR_GP_CNTRL 0x%08x)\n",
- iwl_read32(trans, CSR_GP_CNTRL));
+ cntrl);
+
+ iwl_trans_pcie_dump_regs(trans);
+
+ if (iwlwifi_mod_params.remove_when_gone && cntrl == ~0U) {
+ struct iwl_trans_pcie_removal *removal;
+
+ if (trans_pcie->scheduled_for_removal)
+ goto err;
+
+ IWL_ERR(trans, "Device gone - scheduling removal!\n");
+
+ /*
+ * get a module reference to avoid doing this
+ * while unloading anyway and to avoid
+ * scheduling a work with code that's being
+ * removed.
+ */
+ if (!try_module_get(THIS_MODULE)) {
+ IWL_ERR(trans,
+ "Module is being unloaded - abort\n");
+ goto err;
+ }
+
+ removal = kzalloc(sizeof(*removal), GFP_ATOMIC);
+ if (!removal) {
+ module_put(THIS_MODULE);
+ goto err;
+ }
+ /*
+ * we don't need to clear this flag, because
+ * the trans will be freed and reallocated.
+ */
+ trans_pcie->scheduled_for_removal = true;
+
+ removal->pdev = to_pci_dev(trans->dev);
+ INIT_WORK(&removal->work, iwl_trans_pcie_removal_wk);
+ pci_dev_get(removal->pdev);
+ schedule_work(&removal->work);
+ } else {
+ iwl_write32(trans, CSR_RESET,
+ CSR_RESET_REG_FLAG_FORCE_NMI);
+ }
+
+err:
spin_unlock_irqrestore(&trans_pcie->reg_lock, *flags);
return false;
}
--
2.17.0
