From 6c5f3aacb2963d49a11d4f8accb1188db6a6404b Mon Sep 17 00:00:00 2001 From: Terry Bowman Date: Wed, 18 Oct 2023 19:17:07 +0200 Subject: [PATCH] cxl/pci: Map RCH downstream AER registers for logging protocol errors The restricted CXL host (RCH) error handler will log protocol errors using AER and RAS status registers. The AER and RAS registers need to be virtually memory mapped before enabling interrupts. Create the initializer function devm_cxl_setup_parent_dport() for this when the endpoint is connected with the dport. The initialization sets up the RCH RAS and AER mappings. Add 'struct cxl_regs' to 'struct cxl_dport' for saving a pointer to the RCH downstream port's AER and RAS registers. Signed-off-by: Terry Bowman Co-developed-by: Robert Richter Signed-off-by: Robert Richter Reviewed-by: Jonathan Cameron Link: https://lore.kernel.org/r/20231018171713.1883517-15-rrichter@amd.com Signed-off-by: Dan Williams --- drivers/cxl/core/pci.c | 36 ++++++++++++++++++++++++++++++++++++ drivers/cxl/cxl.h | 10 ++++++++++ 2 files changed, 46 insertions(+) diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index d101fdafb07c5..3b4bb8d050359 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -730,6 +731,38 @@ static bool cxl_handle_endpoint_ras(struct cxl_dev_state *cxlds) #ifdef CONFIG_PCIEAER_CXL +static void cxl_dport_map_rch_aer(struct cxl_dport *dport) +{ + struct cxl_rcrb_info *ri = &dport->rcrb; + void __iomem *dport_aer = NULL; + resource_size_t aer_phys; + struct device *host; + + if (dport->rch && ri->aer_cap) { + host = dport->reg_map.host; + aer_phys = ri->aer_cap + ri->base; + dport_aer = devm_cxl_iomap_block(host, aer_phys, + sizeof(struct aer_capability_regs)); + } + + dport->regs.dport_aer = dport_aer; +} + +static void cxl_dport_map_regs(struct cxl_dport *dport) +{ + struct cxl_register_map *map = &dport->reg_map; + struct device *dev = dport->dport_dev; + + if (!map->component_map.ras.valid) + dev_dbg(dev, "RAS registers not found\n"); + else if (cxl_map_component_regs(map, &dport->regs.component, + BIT(CXL_CM_CAP_CAP_ID_RAS))) + dev_dbg(dev, "Failed to map RAS capability.\n"); + + if (dport->rch) + cxl_dport_map_rch_aer(dport); +} + void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport) { struct device *dport_dev = dport->dport_dev; @@ -738,6 +771,9 @@ void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport) host_bridge = to_pci_host_bridge(dport_dev); if (host_bridge->native_cxl_error) dport->rcrb.aer_cap = cxl_rcrb_to_aer(dport_dev, dport->rcrb.base); + + dport->reg_map.host = host; + cxl_dport_map_regs(dport); } EXPORT_SYMBOL_NS_GPL(cxl_setup_parent_dport, CXL); diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index cdb2ade6ba29f..3b09286d9d526 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -221,6 +221,14 @@ struct cxl_regs { struct_group_tagged(cxl_pmu_regs, pmu_regs, void __iomem *pmu; ); + + /* + * RCH downstream port specific RAS register + * @aer: CXL 3.0 8.2.1.1 RCH Downstream Port RCRB + */ + struct_group_tagged(cxl_rch_regs, rch_regs, + void __iomem *dport_aer; + ); }; struct cxl_reg_map { @@ -623,6 +631,7 @@ struct cxl_rcrb_info { * @rcrb: Data about the Root Complex Register Block layout * @rch: Indicate whether this dport was enumerated in RCH or VH mode * @port: reference to cxl_port that contains this downstream port + * @regs: Dport parsed register blocks */ struct cxl_dport { struct device *dport_dev; @@ -631,6 +640,7 @@ struct cxl_dport { struct cxl_rcrb_info rcrb; bool rch; struct cxl_port *port; + struct cxl_regs regs; }; /** -- 2.30.2