From 987068fcbdb7a085bb11151b91dc6f4c956c4a1b Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Mon, 12 Sep 2016 17:13:40 +0100 Subject: [PATCH] of/irq: Break out msi-map lookup (again) The PCI msi-map code is already doing double-duty translating IDs and retrieving MSI parents, which unsurprisingly is the same functionality we need for the identically-formatted PCI iommu-map property. Drag the core parsing routine up yet another layer into the general OF-PCI code, and further generalise it for either kind of lookup in either flavour of map property. Acked-by: Rob Herring Acked-by: Marc Zyngier Tested-by: Lorenzo Pieralisi Signed-off-by: Robin Murphy Signed-off-by: Will Deacon --- drivers/of/irq.c | 78 ++----------------------------- drivers/of/of_pci.c | 102 +++++++++++++++++++++++++++++++++++++++++ include/linux/of_pci.h | 10 ++++ 3 files changed, 116 insertions(+), 74 deletions(-) diff --git a/drivers/of/irq.c b/drivers/of/irq.c index a2e68f740eda..393fea85eb4e 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -592,87 +593,16 @@ static u32 __of_msi_map_rid(struct device *dev, struct device_node **np, u32 rid_in) { struct device *parent_dev; - struct device_node *msi_controller_node; - struct device_node *msi_np = *np; - u32 map_mask, masked_rid, rid_base, msi_base, rid_len, phandle; - int msi_map_len; - bool matched; u32 rid_out = rid_in; - const __be32 *msi_map = NULL; /* * Walk up the device parent links looking for one with a * "msi-map" property. */ - for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) { - if (!parent_dev->of_node) - continue; - - msi_map = of_get_property(parent_dev->of_node, - "msi-map", &msi_map_len); - if (!msi_map) - continue; - - if (msi_map_len % (4 * sizeof(__be32))) { - dev_err(parent_dev, "Error: Bad msi-map length: %d\n", - msi_map_len); - return rid_out; - } - /* We have a good parent_dev and msi_map, let's use them. */ - break; - } - if (!msi_map) - return rid_out; - - /* The default is to select all bits. */ - map_mask = 0xffffffff; - - /* - * Can be overridden by "msi-map-mask" property. If - * of_property_read_u32() fails, the default is used. - */ - of_property_read_u32(parent_dev->of_node, "msi-map-mask", &map_mask); - - masked_rid = map_mask & rid_in; - matched = false; - while (!matched && msi_map_len >= 4 * sizeof(__be32)) { - rid_base = be32_to_cpup(msi_map + 0); - phandle = be32_to_cpup(msi_map + 1); - msi_base = be32_to_cpup(msi_map + 2); - rid_len = be32_to_cpup(msi_map + 3); - - if (rid_base & ~map_mask) { - dev_err(parent_dev, - "Invalid msi-map translation - msi-map-mask (0x%x) ignores rid-base (0x%x)\n", - map_mask, rid_base); - return rid_out; - } - - msi_controller_node = of_find_node_by_phandle(phandle); - - matched = (masked_rid >= rid_base && - masked_rid < rid_base + rid_len); - if (msi_np) - matched &= msi_np == msi_controller_node; - - if (matched && !msi_np) { - *np = msi_np = msi_controller_node; + for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) + if (!of_pci_map_rid(parent_dev->of_node, rid_in, "msi-map", + "msi-map-mask", np, &rid_out)) break; - } - - of_node_put(msi_controller_node); - msi_map_len -= 4 * sizeof(__be32); - msi_map += 4; - } - if (!matched) - return rid_out; - - rid_out = masked_rid - rid_base + msi_base; - dev_dbg(dev, - "msi-map at: %s, using mask %08x, rid-base: %08x, msi-base: %08x, length: %08x, rid: %08x -> %08x\n", - dev_name(parent_dev), map_mask, rid_base, msi_base, - rid_len, rid_in, rid_out); - return rid_out; } diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 589b30c68e14..b58be12ab277 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -308,3 +308,105 @@ struct msi_controller *of_pci_find_msi_chip_by_node(struct device_node *of_node) EXPORT_SYMBOL_GPL(of_pci_find_msi_chip_by_node); #endif /* CONFIG_PCI_MSI */ + +/** + * of_pci_map_rid - Translate a requester ID through a downstream mapping. + * @np: root complex device node. + * @rid: PCI requester ID to map. + * @map_name: property name of the map to use. + * @map_mask_name: optional property name of the mask to use. + * @target: optional pointer to a target device node. + * @id_out: optional pointer to receive the translated ID. + * + * Given a PCI requester ID, look up the appropriate implementation-defined + * platform ID and/or the target device which receives transactions on that + * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or + * @id_out may be NULL if only the other is required. If @target points to + * a non-NULL device node pointer, only entries targeting that node will be + * matched; if it points to a NULL value, it will receive the device node of + * the first matching target phandle, with a reference held. + * + * Return: 0 on success or a standard error code on failure. + */ +int of_pci_map_rid(struct device_node *np, u32 rid, + const char *map_name, const char *map_mask_name, + struct device_node **target, u32 *id_out) +{ + u32 map_mask, masked_rid; + int map_len; + const __be32 *map = NULL; + + if (!np || !map_name || (!target && !id_out)) + return -EINVAL; + + map = of_get_property(np, map_name, &map_len); + if (!map) { + if (target) + return -ENODEV; + /* Otherwise, no map implies no translation */ + *id_out = rid; + return 0; + } + + if (!map_len || map_len % (4 * sizeof(*map))) { + pr_err("%s: Error: Bad %s length: %d\n", np->full_name, + map_name, map_len); + return -EINVAL; + } + + /* The default is to select all bits. */ + map_mask = 0xffffffff; + + /* + * Can be overridden by "{iommu,msi}-map-mask" property. + * If of_property_read_u32() fails, the default is used. + */ + if (map_mask_name) + of_property_read_u32(np, map_mask_name, &map_mask); + + masked_rid = map_mask & rid; + for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) { + struct device_node *phandle_node; + u32 rid_base = be32_to_cpup(map + 0); + u32 phandle = be32_to_cpup(map + 1); + u32 out_base = be32_to_cpup(map + 2); + u32 rid_len = be32_to_cpup(map + 3); + + if (rid_base & ~map_mask) { + pr_err("%s: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n", + np->full_name, map_name, map_name, + map_mask, rid_base); + return -EFAULT; + } + + if (masked_rid < rid_base || masked_rid >= rid_base + rid_len) + continue; + + phandle_node = of_find_node_by_phandle(phandle); + if (!phandle_node) + return -ENODEV; + + if (target) { + if (*target) + of_node_put(phandle_node); + else + *target = phandle_node; + + if (*target != phandle_node) + continue; + } + + if (id_out) + *id_out = masked_rid - rid_base + out_base; + + pr_debug("%s: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n", + np->full_name, map_name, map_mask, rid_base, out_base, + rid_len, rid, *id_out); + return 0; + } + + pr_err("%s: Invalid %s translation - no match for rid 0x%x on %s\n", + np->full_name, map_name, rid, + target && *target ? (*target)->full_name : "any target"); + return -EFAULT; +} diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index b969e9443962..7fd5cfce9140 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -17,6 +17,9 @@ int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); int of_get_pci_domain_nr(struct device_node *node); void of_pci_check_probe_only(void); +int of_pci_map_rid(struct device_node *np, u32 rid, + const char *map_name, const char *map_mask_name, + struct device_node **target, u32 *id_out); #else static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) { @@ -52,6 +55,13 @@ of_get_pci_domain_nr(struct device_node *node) return -1; } +static inline int of_pci_map_rid(struct device_node *np, u32 rid, + const char *map_name, const char *map_mask_name, + struct device_node **target, u32 *id_out) +{ + return -EINVAL; +} + static inline void of_pci_check_probe_only(void) { } #endif -- 2.20.1