diff options
Diffstat (limited to 'drivers/pci/pcie/dpc.c')
| -rw-r--r-- | drivers/pci/pcie/dpc.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c new file mode 100644 index 000000000000..8c57d607e603 --- /dev/null +++ b/drivers/pci/pcie/dpc.c @@ -0,0 +1,307 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCI Express Downstream Port Containment services driver + * Author: Keith Busch <keith.busch@intel.com> + * + * Copyright (C) 2016 Intel Corp. + */ + +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/pci.h> + +#include "portdrv.h" +#include "../pci.h" +#include "aer/aerdrv.h" + +struct dpc_dev { + struct pcie_device *dev; + struct work_struct work; + u16 cap_pos; + bool rp_extensions; + u32 rp_pio_status; + u8 rp_log_size; +}; + +static const char * const rp_pio_error_string[] = { + "Configuration Request received UR Completion", /* Bit Position 0 */ + "Configuration Request received CA Completion", /* Bit Position 1 */ + "Configuration Request Completion Timeout", /* Bit Position 2 */ + NULL, + NULL, + NULL, + NULL, + NULL, + "I/O Request received UR Completion", /* Bit Position 8 */ + "I/O Request received CA Completion", /* Bit Position 9 */ + "I/O Request Completion Timeout", /* Bit Position 10 */ + NULL, + NULL, + NULL, + NULL, + NULL, + "Memory Request received UR Completion", /* Bit Position 16 */ + "Memory Request received CA Completion", /* Bit Position 17 */ + "Memory Request Completion Timeout", /* Bit Position 18 */ +}; + +static int dpc_wait_rp_inactive(struct dpc_dev *dpc) +{ + unsigned long timeout = jiffies + HZ; + struct pci_dev *pdev = dpc->dev->port; + struct device *dev = &dpc->dev->device; + u16 cap = dpc->cap_pos, status; + + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); + while (status & PCI_EXP_DPC_RP_BUSY && + !time_after(jiffies, timeout)) { + msleep(10); + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); + } + if (status & PCI_EXP_DPC_RP_BUSY) { + dev_warn(dev, "DPC root port still busy\n"); + return -EBUSY; + } + return 0; +} + +static void dpc_wait_link_inactive(struct dpc_dev *dpc) +{ + unsigned long timeout = jiffies + HZ; + struct pci_dev *pdev = dpc->dev->port; + struct device *dev = &dpc->dev->device; + u16 lnk_status; + + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); + while (lnk_status & PCI_EXP_LNKSTA_DLLLA && + !time_after(jiffies, timeout)) { + msleep(10); + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); + } + if (lnk_status & PCI_EXP_LNKSTA_DLLLA) + dev_warn(dev, "Link state not disabled for DPC event\n"); +} + +static void dpc_work(struct work_struct *work) +{ + struct dpc_dev *dpc = container_of(work, struct dpc_dev, work); + struct pci_dev *dev, *temp, *pdev = dpc->dev->port; + struct pci_bus *parent = pdev->subordinate; + u16 cap = dpc->cap_pos, ctl; + + pci_lock_rescan_remove(); + list_for_each_entry_safe_reverse(dev, temp, &parent->devices, + bus_list) { + pci_dev_get(dev); + pci_dev_set_disconnected(dev, NULL); + if (pci_has_subordinate(dev)) + pci_walk_bus(dev->subordinate, + pci_dev_set_disconnected, NULL); + pci_stop_and_remove_bus_device(dev); + pci_dev_put(dev); + } + pci_unlock_rescan_remove(); + + dpc_wait_link_inactive(dpc); + if (dpc->rp_extensions && dpc_wait_rp_inactive(dpc)) + return; + if (dpc->rp_extensions && dpc->rp_pio_status) { + pci_write_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, + dpc->rp_pio_status); + dpc->rp_pio_status = 0; + } + + pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, + PCI_EXP_DPC_STATUS_TRIGGER | PCI_EXP_DPC_STATUS_INTERRUPT); + + pci_read_config_word(pdev, cap + PCI_EXP_DPC_CTL, &ctl); + pci_write_config_word(pdev, cap + PCI_EXP_DPC_CTL, + ctl | PCI_EXP_DPC_CTL_INT_EN); +} + +static void dpc_process_rp_pio_error(struct dpc_dev *dpc) +{ + struct device *dev = &dpc->dev->device; + struct pci_dev *pdev = dpc->dev->port; + u16 cap = dpc->cap_pos, dpc_status, first_error; + u32 status, mask, sev, syserr, exc, dw0, dw1, dw2, dw3, log, prefix; + int i; + + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_STATUS, &status); + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_MASK, &mask); + dev_err(dev, "rp_pio_status: %#010x, rp_pio_mask: %#010x\n", + status, mask); + + dpc->rp_pio_status = status; + + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SEVERITY, &sev); + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_SYSERROR, &syserr); + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_EXCEPTION, &exc); + dev_err(dev, "RP PIO severity=%#010x, syserror=%#010x, exception=%#010x\n", + sev, syserr, exc); + + /* Get First Error Pointer */ + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &dpc_status); + first_error = (dpc_status & 0x1f00) >> 8; + + status &= ~mask; + for (i = 0; i < ARRAY_SIZE(rp_pio_error_string); i++) { + if (status & (1 << i)) + dev_err(dev, "[%2d] %s%s\n", i, rp_pio_error_string[i], + first_error == i ? " (First)" : ""); + } + + if (dpc->rp_log_size < 4) + return; + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG, + &dw0); + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 4, + &dw1); + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 8, + &dw2); + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_HEADER_LOG + 12, + &dw3); + dev_err(dev, "TLP Header: %#010x %#010x %#010x %#010x\n", + dw0, dw1, dw2, dw3); + + if (dpc->rp_log_size < 5) + return; + pci_read_config_dword(pdev, cap + PCI_EXP_DPC_RP_PIO_IMPSPEC_LOG, &log); + dev_err(dev, "RP PIO ImpSpec Log %#010x\n", log); + + for (i = 0; i < dpc->rp_log_size - 5; i++) { + pci_read_config_dword(pdev, + cap + PCI_EXP_DPC_RP_PIO_TLPPREFIX_LOG, &prefix); + dev_err(dev, "TLP Prefix Header: dw%d, %#010x\n", i, prefix); + } +} + +static irqreturn_t dpc_irq(int irq, void *context) +{ + struct dpc_dev *dpc = (struct dpc_dev *)context; + struct pci_dev *pdev = dpc->dev->port; + struct device *dev = &dpc->dev->device; + u16 cap = dpc->cap_pos, ctl, status, source, reason, ext_reason; + + pci_read_config_word(pdev, cap + PCI_EXP_DPC_CTL, &ctl); + + if (!(ctl & PCI_EXP_DPC_CTL_INT_EN) || ctl == (u16)(~0)) + return IRQ_NONE; + + pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); + + if (!(status & PCI_EXP_DPC_STATUS_INTERRUPT)) + return IRQ_NONE; + + if (!(status & PCI_EXP_DPC_STATUS_TRIGGER)) { + pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, + PCI_EXP_DPC_STATUS_INTERRUPT); + return IRQ_HANDLED; + } + + pci_write_config_word(pdev, cap + PCI_EXP_DPC_CTL, + ctl & ~PCI_EXP_DPC_CTL_INT_EN); + + pci_read_config_word(pdev, cap + PCI_EXP_DPC_SOURCE_ID, + &source); + + dev_info(dev, "DPC containment event, status:%#06x source:%#06x\n", + status, source); + + reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN) >> 1; + ext_reason = (status & PCI_EXP_DPC_STATUS_TRIGGER_RSN_EXT) >> 5; + + dev_warn(dev, "DPC %s detected, remove downstream devices\n", + (reason == 0) ? "unmasked uncorrectable error" : + (reason == 1) ? "ERR_NONFATAL" : + (reason == 2) ? "ERR_FATAL" : + (ext_reason == 0) ? "RP PIO error" : + (ext_reason == 1) ? "software trigger" : + "reserved error"); + /* show RP PIO error detail information */ + if (dpc->rp_extensions && reason == 3 && ext_reason == 0) + dpc_process_rp_pio_error(dpc); + + schedule_work(&dpc->work); + + return IRQ_HANDLED; +} + +#define FLAG(x, y) (((x) & (y)) ? '+' : '-') +static int dpc_probe(struct pcie_device *dev) +{ + struct dpc_dev *dpc; + struct pci_dev *pdev = dev->port; + struct device *device = &dev->device; + int status; + u16 ctl, cap; + + if (pcie_aer_get_firmware_first(pdev)) + return -ENOTSUPP; + + dpc = devm_kzalloc(device, sizeof(*dpc), GFP_KERNEL); + if (!dpc) + return -ENOMEM; + + dpc->cap_pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DPC); + dpc->dev = dev; + INIT_WORK(&dpc->work, dpc_work); + set_service_data(dev, dpc); + + status = devm_request_irq(device, dev->irq, dpc_irq, IRQF_SHARED, + "pcie-dpc", dpc); + if (status) { + dev_warn(device, "request IRQ%d failed: %d\n", dev->irq, + status); + return status; + } + + pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CAP, &cap); + pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl); + + dpc->rp_extensions = (cap & PCI_EXP_DPC_CAP_RP_EXT); + if (dpc->rp_extensions) { + dpc->rp_log_size = (cap & PCI_EXP_DPC_RP_PIO_LOG_SIZE) >> 8; + if (dpc->rp_log_size < 4 || dpc->rp_log_size > 9) { + dev_err(device, "RP PIO log size %u is invalid\n", + dpc->rp_log_size); + dpc->rp_log_size = 0; + } + } + + ctl = (ctl & 0xfff4) | PCI_EXP_DPC_CTL_EN_NONFATAL | PCI_EXP_DPC_CTL_INT_EN; + pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl); + + dev_info(device, "DPC error containment capabilities: Int Msg #%d, RPExt%c PoisonedTLP%c SwTrigger%c RP PIO Log %d, DL_ActiveErr%c\n", + cap & PCI_EXP_DPC_IRQ, FLAG(cap, PCI_EXP_DPC_CAP_RP_EXT), + FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP), + FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), dpc->rp_log_size, + FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE)); + return status; +} + +static void dpc_remove(struct pcie_device *dev) +{ + struct dpc_dev *dpc = get_service_data(dev); + struct pci_dev *pdev = dev->port; + u16 ctl; + + pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl); + ctl &= ~(PCI_EXP_DPC_CTL_EN_NONFATAL | PCI_EXP_DPC_CTL_INT_EN); + pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl); +} + +static struct pcie_port_service_driver dpcdriver = { + .name = "dpc", + .port_type = PCIE_ANY_PORT, + .service = PCIE_PORT_SERVICE_DPC, + .probe = dpc_probe, + .remove = dpc_remove, +}; + +static int __init dpc_service_init(void) +{ + return pcie_port_service_register(&dpcdriver); +} +device_initcall(dpc_service_init); |