From ce06bf570390fb8b41d581e5d594727b51367179 Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Fri, 24 Jun 2022 17:39:46 +0300 Subject: PCI: dwc: Check iATU in/outbound range setup status Make the DWC PCIe RC/EP safer and more verbose for invalid or failed inbound and outbound iATU window setups. Silently ignoring iATU regions setup errors may cause unpredictable errors. For instance if a cfg or IO window fails to be activated, then any CFG/IO requested won't reach target PCIe devices and the corresponding accessors will return platform-specific random values. [bhelgaas: trim commit log] Link: https://lore.kernel.org/r/20220624143947.8991-15-Sergey.Semin@baikalelectronics.ru Signed-off-by: Serge Semin Signed-off-by: Bjorn Helgaas Reviewed-by: Rob Herring Reviewed-by: Manivannan Sadhasivam --- drivers/pci/controller/dwc/pcie-designware-host.c | 153 ++++++++++++++-------- 1 file changed, 100 insertions(+), 53 deletions(-) (limited to 'drivers/pci/controller/dwc/pcie-designware-host.c') diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index aaf1914388b2..6993ce9e856d 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -412,7 +412,9 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp) dw_pcie_iatu_detect(pci); - dw_pcie_setup_rc(pp); + ret = dw_pcie_setup_rc(pp); + if (ret) + goto err_free_msi; if (!dw_pcie_link_up(pci)) { ret = dw_pcie_start_link(pci); @@ -466,10 +468,10 @@ EXPORT_SYMBOL_GPL(dw_pcie_host_deinit); static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus, unsigned int devfn, int where) { - int type; - u32 busdev; struct dw_pcie_rp *pp = bus->sysdata; struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + int type, ret; + u32 busdev; /* * Checking whether the link is up here is a last line of defense @@ -490,8 +492,10 @@ static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus, else type = PCIE_ATU_TYPE_CFG1; - - dw_pcie_prog_outbound_atu(pci, 0, type, pp->cfg0_base, busdev, pp->cfg0_size); + ret = dw_pcie_prog_outbound_atu(pci, 0, type, pp->cfg0_base, busdev, + pp->cfg0_size); + if (ret) + return NULL; return pp->va_cfg0_base + where; } @@ -499,33 +503,45 @@ static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus, static int dw_pcie_rd_other_conf(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) { - int ret; struct dw_pcie_rp *pp = bus->sysdata; struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + int ret; ret = pci_generic_config_read(bus, devfn, where, size, val); + if (ret != PCIBIOS_SUCCESSFUL) + return ret; - if (!ret && pp->cfg0_io_shared) - dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO, pp->io_base, - pp->io_bus_addr, pp->io_size); + if (pp->cfg0_io_shared) { + ret = dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO, + pp->io_base, pp->io_bus_addr, + pp->io_size); + if (ret) + return PCIBIOS_SET_FAILED; + } - return ret; + return PCIBIOS_SUCCESSFUL; } static int dw_pcie_wr_other_conf(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) { - int ret; struct dw_pcie_rp *pp = bus->sysdata; struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + int ret; ret = pci_generic_config_write(bus, devfn, where, size, val); + if (ret != PCIBIOS_SUCCESSFUL) + return ret; - if (!ret && pp->cfg0_io_shared) - dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO, pp->io_base, - pp->io_bus_addr, pp->io_size); + if (pp->cfg0_io_shared) { + ret = dw_pcie_prog_outbound_atu(pci, 0, PCIE_ATU_TYPE_IO, + pp->io_base, pp->io_bus_addr, + pp->io_size); + if (ret) + return PCIBIOS_SET_FAILED; + } - return ret; + return PCIBIOS_SUCCESSFUL; } static struct pci_ops dw_child_pcie_ops = { @@ -552,10 +568,72 @@ static struct pci_ops dw_pcie_ops = { .write = pci_generic_config_write, }; -void dw_pcie_setup_rc(struct dw_pcie_rp *pp) +static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp) { - u32 val, ctrl, num_ctrls; struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct resource_entry *entry; + int i, ret; + + /* Note the very first outbound ATU is used for CFG IOs */ + if (!pci->num_ob_windows) { + dev_err(pci->dev, "No outbound iATU found\n"); + return -EINVAL; + } + + /* + * Ensure all outbound windows are disabled before proceeding with + * the MEM/IO ranges setups. + */ + for (i = 0; i < pci->num_ob_windows; i++) + dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_OB, i); + + i = 0; + resource_list_for_each_entry(entry, &pp->bridge->windows) { + if (resource_type(entry->res) != IORESOURCE_MEM) + continue; + + if (pci->num_ob_windows <= ++i) + break; + + ret = dw_pcie_prog_outbound_atu(pci, i, PCIE_ATU_TYPE_MEM, + entry->res->start, + entry->res->start - entry->offset, + resource_size(entry->res)); + if (ret) { + dev_err(pci->dev, "Failed to set MEM range %pr\n", + entry->res); + return ret; + } + } + + if (pp->io_size) { + if (pci->num_ob_windows > ++i) { + ret = dw_pcie_prog_outbound_atu(pci, i, PCIE_ATU_TYPE_IO, + pp->io_base, + pp->io_bus_addr, + pp->io_size); + if (ret) { + dev_err(pci->dev, "Failed to set IO range %pr\n", + entry->res); + return ret; + } + } else { + pp->cfg0_io_shared = true; + } + } + + if (pci->num_ob_windows <= i) + dev_warn(pci->dev, "Resources exceed number of ATU entries (%d)\n", + pci->num_ob_windows); + + return 0; +} + +int dw_pcie_setup_rc(struct dw_pcie_rp *pp) +{ + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + u32 val, ctrl, num_ctrls; + int ret; /* * Enable DBI read-only registers for writing/updating configuration. @@ -610,42 +688,9 @@ void dw_pcie_setup_rc(struct dw_pcie_rp *pp) * ATU, so we should not program the ATU here. */ if (pp->bridge->child_ops == &dw_child_pcie_ops) { - int i, atu_idx = 0; - struct resource_entry *entry; - - /* - * Disable all outbound windows to make sure a transaction - * can't match multiple windows. - */ - for (i = 0; i < pci->num_ob_windows; i++) - dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_OB, i); - - /* Get last memory resource entry */ - resource_list_for_each_entry(entry, &pp->bridge->windows) { - if (resource_type(entry->res) != IORESOURCE_MEM) - continue; - - if (pci->num_ob_windows <= ++atu_idx) - break; - - dw_pcie_prog_outbound_atu(pci, atu_idx, - PCIE_ATU_TYPE_MEM, entry->res->start, - entry->res->start - entry->offset, - resource_size(entry->res)); - } - - if (pp->io_size) { - if (pci->num_ob_windows > ++atu_idx) - dw_pcie_prog_outbound_atu(pci, atu_idx, - PCIE_ATU_TYPE_IO, pp->io_base, - pp->io_bus_addr, pp->io_size); - else - pp->cfg0_io_shared = true; - } - - if (pci->num_ob_windows <= atu_idx) - dev_warn(pci->dev, "Resources exceed number of ATU entries (%d)\n", - pci->num_ob_windows); + ret = dw_pcie_iatu_setup(pp); + if (ret) + return ret; } dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 0); @@ -658,5 +703,7 @@ void dw_pcie_setup_rc(struct dw_pcie_rp *pp) dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val); dw_pcie_dbi_ro_wr_dis(pci); + + return 0; } EXPORT_SYMBOL_GPL(dw_pcie_setup_rc); -- cgit v1.2.3-59-g8ed1b