diff options
author | Bjorn Helgaas <bhelgaas@google.com> | 2024-05-17 02:14:09 +0300 |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2024-05-17 02:14:09 +0300 |
commit | 83711a1ab210cf59d30a3e65f72268f5404c1870 (patch) | |
tree | 65f9202cc2aa46c84b87f4c4f71d76eb3f388f01 /drivers | |
parent | a6faf3f450ecdb084128751e8fda0e515283da39 (diff) | |
parent | 934edcd436dca0447e0d3691a908394ba16d06c3 (diff) | |
download | linux-83711a1ab210cf59d30a3e65f72268f5404c1870.tar.xz |
Merge branch 'pci/cxl'
- Lock the upstream bridge while using it to perform a Secondary Bus Reset
(Dave Jiang)
- Return failure when attempting Secondary Bus Reset below a CXL Port that
has SBR masked (Dave Jiang)
- Add a "cxl_bus" reset method that temporarily unmasks SBR (Dave Jiang)
- Add a warning if we reset a CXL type 3 memory device that was in use
while being reset (Dave Jiang)
* pci/cxl:
cxl: Add post-reset warning if reset results in loss of previously committed HDM decoders
PCI/CXL: Add 'cxl_bus' reset method for devices below CXL Ports
PCI/CXL: Fail bus reset if upstream CXL Port has SBR masked
PCI: Lock upstream bridge for pci_reset_function()
PCI/CXL: Move CXL Vendor ID to pci_ids.h
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/cxl/core/pci.c | 35 | ||||
-rw-r--r-- | drivers/cxl/core/regs.c | 2 | ||||
-rw-r--r-- | drivers/cxl/cxl.h | 2 | ||||
-rw-r--r-- | drivers/cxl/cxlpci.h | 1 | ||||
-rw-r--r-- | drivers/cxl/pci.c | 24 | ||||
-rw-r--r-- | drivers/pci/access.c | 4 | ||||
-rw-r--r-- | drivers/pci/pci.c | 94 | ||||
-rw-r--r-- | drivers/pci/probe.c | 3 | ||||
-rw-r--r-- | drivers/perf/cxl_pmu.c | 2 |
9 files changed, 160 insertions, 7 deletions
diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index 0df09bd79408..8567dd11eaac 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -525,7 +525,7 @@ static int cxl_cdat_get_length(struct device *dev, __le32 response[2]; int rc; - rc = pci_doe(doe_mb, PCI_DVSEC_VENDOR_ID_CXL, + rc = pci_doe(doe_mb, PCI_VENDOR_ID_CXL, CXL_DOE_PROTOCOL_TABLE_ACCESS, &request, sizeof(request), &response, sizeof(response)); @@ -555,7 +555,7 @@ static int cxl_cdat_read_table(struct device *dev, __le32 request = CDAT_DOE_REQ(entry_handle); int rc; - rc = pci_doe(doe_mb, PCI_DVSEC_VENDOR_ID_CXL, + rc = pci_doe(doe_mb, PCI_VENDOR_ID_CXL, CXL_DOE_PROTOCOL_TABLE_ACCESS, &request, sizeof(request), rsp, sizeof(*rsp) + remaining); @@ -640,7 +640,7 @@ void read_cdat_data(struct cxl_port *port) if (!pdev) return; - doe_mb = pci_find_doe_mailbox(pdev, PCI_DVSEC_VENDOR_ID_CXL, + doe_mb = pci_find_doe_mailbox(pdev, PCI_VENDOR_ID_CXL, CXL_DOE_PROTOCOL_TABLE_ACCESS); if (!doe_mb) { dev_dbg(dev, "No CDAT mailbox\n"); @@ -1045,3 +1045,32 @@ long cxl_pci_get_latency(struct pci_dev *pdev) return cxl_flit_size(pdev) * MEGA / bw; } + +static int __cxl_endpoint_decoder_reset_detected(struct device *dev, void *data) +{ + struct cxl_port *port = data; + struct cxl_decoder *cxld; + struct cxl_hdm *cxlhdm; + void __iomem *hdm; + u32 ctrl; + + if (!is_endpoint_decoder(dev)) + return 0; + + cxld = to_cxl_decoder(dev); + if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0) + return 0; + + cxlhdm = dev_get_drvdata(&port->dev); + hdm = cxlhdm->regs.hdm_decoder; + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); + + return !FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl); +} + +bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port) +{ + return device_for_each_child(&port->dev, port, + __cxl_endpoint_decoder_reset_detected); +} +EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_reset_detected, CXL); diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c index 372786f80955..da52fc9e234b 100644 --- a/drivers/cxl/core/regs.c +++ b/drivers/cxl/core/regs.c @@ -313,7 +313,7 @@ int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type, .resource = CXL_RESOURCE_NONE, }; - regloc = pci_find_dvsec_capability(pdev, PCI_DVSEC_VENDOR_ID_CXL, + regloc = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL, CXL_DVSEC_REG_LOCATOR); if (!regloc) return -ENXIO; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 534e25e2f0a4..e3c237c50b59 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -895,6 +895,8 @@ void cxl_coordinates_combine(struct access_coordinate *out, struct access_coordinate *c1, struct access_coordinate *c2); +bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port); + /* * Unit test builds overrides this to __weak, find the 'strong' version * of these symbols in tools/testing/cxl/. diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h index 93992a1c8eec..4da07727ab9c 100644 --- a/drivers/cxl/cxlpci.h +++ b/drivers/cxl/cxlpci.h @@ -13,7 +13,6 @@ * "DVSEC" redundancies removed. When obvious, abbreviations may be used. */ #define PCI_DVSEC_HEADER1_LENGTH_MASK GENMASK(31, 20) -#define PCI_DVSEC_VENDOR_ID_CXL 0x1E98 /* CXL 2.0 8.1.3: PCIe DVSEC for CXL Device */ #define CXL_DVSEC_PCIE_DEVICE 0 diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 2ff361e756d6..f9d65f72601b 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -817,7 +817,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) cxlds->rcd = is_cxl_restricted(pdev); cxlds->serial = pci_get_dsn(pdev); cxlds->cxl_dvsec = pci_find_dvsec_capability( - pdev, PCI_DVSEC_VENDOR_ID_CXL, CXL_DVSEC_PCIE_DEVICE); + pdev, PCI_VENDOR_ID_CXL, CXL_DVSEC_PCIE_DEVICE); if (!cxlds->cxl_dvsec) dev_warn(&pdev->dev, "Device DVSEC not present, skip CXL.mem init\n"); @@ -957,11 +957,33 @@ static void cxl_error_resume(struct pci_dev *pdev) dev->driver ? "successful" : "failed"); } +static void cxl_reset_done(struct pci_dev *pdev) +{ + struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); + struct cxl_memdev *cxlmd = cxlds->cxlmd; + struct device *dev = &pdev->dev; + + /* + * FLR does not expect to touch the HDM decoders and related + * registers. SBR, however, will wipe all device configurations. + * Issue a warning if there was an active decoder before the reset + * that no longer exists. + */ + guard(device)(&cxlmd->dev); + if (cxlmd->endpoint && + cxl_endpoint_decoder_reset_detected(cxlmd->endpoint)) { + dev_crit(dev, "SBR happened without memory regions removal.\n"); + dev_crit(dev, "System may be unstable if regions hosted system memory.\n"); + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + } +} + static const struct pci_error_handlers cxl_error_handlers = { .error_detected = cxl_error_detected, .slot_reset = cxl_slot_reset, .resume = cxl_error_resume, .cor_error_detected = cxl_cor_error_detected, + .reset_done = cxl_reset_done, }; static struct pci_driver cxl_pci_driver = { diff --git a/drivers/pci/access.c b/drivers/pci/access.c index 6449056b57dd..36f10c7f9ef5 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -275,6 +275,8 @@ void pci_cfg_access_lock(struct pci_dev *dev) { might_sleep(); + lock_map_acquire(&dev->cfg_access_lock); + raw_spin_lock_irq(&pci_lock); if (dev->block_cfg_access) pci_wait_cfg(dev); @@ -329,6 +331,8 @@ void pci_cfg_access_unlock(struct pci_dev *dev) raw_spin_unlock_irqrestore(&pci_lock, flags); wake_up_all(&pci_cfg_wait); + + lock_map_release(&dev->cfg_access_lock); } EXPORT_SYMBOL_GPL(pci_cfg_access_unlock); diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e5f243dd4288..13605261a881 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4879,6 +4879,7 @@ void __weak pcibios_reset_secondary_bus(struct pci_dev *dev) */ int pci_bridge_secondary_bus_reset(struct pci_dev *dev) { + lock_map_assert_held(&dev->cfg_access_lock); pcibios_reset_secondary_bus(dev); return pci_bridge_wait_for_secondary_bus(dev, "bus reset"); @@ -4927,16 +4928,96 @@ static int pci_dev_reset_slot_function(struct pci_dev *dev, bool probe) return pci_reset_hotplug_slot(dev->slot->hotplug, probe); } +static u16 cxl_port_dvsec(struct pci_dev *dev) +{ + return pci_find_dvsec_capability(dev, PCI_VENDOR_ID_CXL, + PCI_DVSEC_CXL_PORT); +} + +static bool cxl_sbr_masked(struct pci_dev *dev) +{ + u16 dvsec, reg; + int rc; + + dvsec = cxl_port_dvsec(dev); + if (!dvsec) + return false; + + rc = pci_read_config_word(dev, dvsec + PCI_DVSEC_CXL_PORT_CTL, ®); + if (rc || PCI_POSSIBLE_ERROR(reg)) + return false; + + /* + * Per CXL spec r3.1, sec 8.1.5.2, when "Unmask SBR" is 0, the SBR + * bit in Bridge Control has no effect. When 1, the Port generates + * hot reset when the SBR bit is set to 1. + */ + if (reg & PCI_DVSEC_CXL_PORT_CTL_UNMASK_SBR) + return false; + + return true; +} + static int pci_reset_bus_function(struct pci_dev *dev, bool probe) { + struct pci_dev *bridge = pci_upstream_bridge(dev); int rc; + /* + * If "dev" is below a CXL port that has SBR control masked, SBR + * won't do anything, so return error. + */ + if (bridge && cxl_sbr_masked(bridge)) { + if (probe) + return 0; + + return -ENOTTY; + } + rc = pci_dev_reset_slot_function(dev, probe); if (rc != -ENOTTY) return rc; return pci_parent_bus_reset(dev, probe); } +static int cxl_reset_bus_function(struct pci_dev *dev, bool probe) +{ + struct pci_dev *bridge; + u16 dvsec, reg, val; + int rc; + + bridge = pci_upstream_bridge(dev); + if (!bridge) + return -ENOTTY; + + dvsec = cxl_port_dvsec(bridge); + if (!dvsec) + return -ENOTTY; + + if (probe) + return 0; + + rc = pci_read_config_word(bridge, dvsec + PCI_DVSEC_CXL_PORT_CTL, ®); + if (rc) + return -ENOTTY; + + if (reg & PCI_DVSEC_CXL_PORT_CTL_UNMASK_SBR) { + val = reg; + } else { + val = reg | PCI_DVSEC_CXL_PORT_CTL_UNMASK_SBR; + pci_write_config_word(bridge, dvsec + PCI_DVSEC_CXL_PORT_CTL, + val); + } + + rc = pci_reset_bus_function(dev, probe); + + if (reg != val) + pci_write_config_word(bridge, dvsec + PCI_DVSEC_CXL_PORT_CTL, + reg); + + return rc; +} + void pci_dev_lock(struct pci_dev *dev) { /* block PM suspend, driver probe, etc. */ @@ -5021,6 +5102,7 @@ static const struct pci_reset_fn_method pci_reset_fn_methods[] = { { pci_af_flr, .name = "af_flr" }, { pci_pm_reset, .name = "pm" }, { pci_reset_bus_function, .name = "bus" }, + { cxl_reset_bus_function, .name = "cxl_bus" }, }; static ssize_t reset_method_show(struct device *dev, @@ -5245,11 +5327,20 @@ void pci_init_reset_methods(struct pci_dev *dev) */ int pci_reset_function(struct pci_dev *dev) { + struct pci_dev *bridge; int rc; if (!pci_reset_supported(dev)) return -ENOTTY; + /* + * If there's no upstream bridge, no locking is needed since there is + * no upstream bridge configuration to hold consistent. + */ + bridge = pci_upstream_bridge(dev); + if (bridge) + pci_dev_lock(bridge); + pci_dev_lock(dev); pci_dev_save_and_disable(dev); @@ -5258,6 +5349,9 @@ int pci_reset_function(struct pci_dev *dev) pci_dev_restore(dev); pci_dev_unlock(dev); + if (bridge) + pci_dev_unlock(bridge); + return rc; } EXPORT_SYMBOL_GPL(pci_reset_function); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 1325fbae2f28..a3da776bf986 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2543,6 +2543,9 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) dev->dev.dma_mask = &dev->dma_mask; dev->dev.dma_parms = &dev->dma_parms; dev->dev.coherent_dma_mask = 0xffffffffull; + lockdep_register_key(&dev->cfg_access_key); + lockdep_init_map(&dev->cfg_access_lock, dev_name(&dev->dev), + &dev->cfg_access_key, 0); dma_set_max_seg_size(&dev->dev, 65536); dma_set_seg_boundary(&dev->dev, 0xffffffff); diff --git a/drivers/perf/cxl_pmu.c b/drivers/perf/cxl_pmu.c index 308c9969642e..a1b742b1a735 100644 --- a/drivers/perf/cxl_pmu.c +++ b/drivers/perf/cxl_pmu.c @@ -345,7 +345,7 @@ static ssize_t cxl_pmu_event_sysfs_show(struct device *dev, /* For CXL spec defined events */ #define CXL_PMU_EVENT_CXL_ATTR(_name, _gid, _msk) \ - CXL_PMU_EVENT_ATTR(_name, PCI_DVSEC_VENDOR_ID_CXL, _gid, _msk) + CXL_PMU_EVENT_ATTR(_name, PCI_VENDOR_ID_CXL, _gid, _msk) static struct attribute *cxl_pmu_event_attrs[] = { CXL_PMU_EVENT_CXL_ATTR(clock_ticks, CXL_PMU_GID_CLOCK_TICKS, BIT(0)), |