diff --git a/Documentation/devicetree/bindings/pci/pci-msi.txt b/Documentation/devicetree/bindings/pci/pci-msi.txt new file mode 100644 index 000000000000..9b3cc817d181 --- /dev/null +++ b/Documentation/devicetree/bindings/pci/pci-msi.txt @@ -0,0 +1,220 @@ +This document describes the generic device tree binding for describing the +relationship between PCI devices and MSI controllers. + +Each PCI device under a root complex is uniquely identified by its Requester ID +(AKA RID). A Requester ID is a triplet of a Bus number, Device number, and +Function number. + +For the purpose of this document, when treated as a numeric value, a RID is +formatted such that: + +* Bits [15:8] are the Bus number. +* Bits [7:3] are the Device number. +* Bits [2:0] are the Function number. +* Any other bits required for padding must be zero. + +MSIs may be distinguished in part through the use of sideband data accompanying +writes. In the case of PCI devices, this sideband data may be derived from the +Requester ID. A mechanism is required to associate a device with both the MSI +controllers it can address, and the sideband data that will be associated with +its writes to those controllers. + +For generic MSI bindings, see +Documentation/devicetree/bindings/interrupt-controller/msi.txt. + + +PCI root complex +================ + +Optional properties +------------------- + +- msi-map: Maps a Requester ID to an MSI controller and associated + msi-specifier data. The property is an arbitrary number of tuples of + (rid-base,msi-controller,msi-base,length), where: + + * rid-base is a single cell describing the first RID matched by the entry. + + * msi-controller is a single phandle to an MSI controller + + * msi-base is an msi-specifier describing the msi-specifier produced for the + first RID matched by the entry. + + * length is a single cell describing how many consecutive RIDs are matched + following the rid-base. + + Any RID r in the interval [rid-base, rid-base + length) is associated with + the listed msi-controller, with the msi-specifier (r - rid-base + msi-base). + +- msi-map-mask: A mask to be applied to each Requester ID prior to being mapped + to an msi-specifier per the msi-map property. + +- msi-parent: Describes the MSI parent of the root complex itself. Where + the root complex and MSI controller do not pass sideband data with MSI + writes, this property may be used to describe the MSI controller(s) + used by PCI devices under the root complex, if defined as such in the + binding for the root complex. + + +Example (1) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, identity-mapped. + */ + msi-map = <0x0 &msi_a 0x0 0x10000>, + }; +}; + + +Example (2) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, masked to only the device and function bits. + */ + msi-map = <0x0 &msi_a 0x0 0x100>, + msi-map-mask = <0xff> + }; +}; + + +Example (3) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, but the high bit of the bus number is + * ignored. + */ + msi-map = <0x0000 &msi 0x0000 0x8000>, + <0x8000 &msi 0x0000 0x8000>; + }; +}; + + +Example (4) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@f { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to the MSI controller is + * the RID, but the high bit of the bus number is + * negated. + */ + msi-map = <0x0000 &msi 0x8000 0x8000>, + <0x8000 &msi 0x0000 0x8000>; + }; +}; + + +Example (5) +=========== + +/ { + #address-cells = <1>; + #size-cells = <1>; + + msi_a: msi-controller@a { + reg = <0xa 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + msi_b: msi-controller@b { + reg = <0xb 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + msi_c: msi-controller@c { + reg = <0xc 0x1>; + compatible = "vendor,some-controller"; + msi-controller; + #msi-cells = <1>; + }; + + pci: pci@c { + reg = <0xf 0x1>; + compatible = "vendor,pcie-root-complex"; + device_type = "pci"; + + /* + * The sideband data provided to MSI controller a is the + * RID, but the high bit of the bus number is negated. + * The sideband data provided to MSI controller b is the + * RID, identity-mapped. + * MSI controller c is not addressable. + */ + msi-map = <0x0000 &msi_a 0x8000 0x08000>, + <0x8000 &msi_a 0x0000 0x08000>, + <0x0000 &msi_b 0x0000 0x10000>; + }; +}; diff --git a/drivers/irqchip/irq-gic-v3-its-pci-msi.c b/drivers/irqchip/irq-gic-v3-its-pci-msi.c index 693c2f9ae898..aee60ed025dc 100644 --- a/drivers/irqchip/irq-gic-v3-its-pci-msi.c +++ b/drivers/irqchip/irq-gic-v3-its-pci-msi.c @@ -42,7 +42,6 @@ static struct irq_chip its_msi_irq_chip = { struct its_pci_alias { struct pci_dev *pdev; - u32 dev_id; u32 count; }; @@ -60,7 +59,6 @@ static int its_get_pci_alias(struct pci_dev *pdev, u16 alias, void *data) { struct its_pci_alias *dev_alias = data; - dev_alias->dev_id = alias; if (pdev != dev_alias->pdev) dev_alias->count += its_pci_msi_vec_count(pdev); @@ -86,7 +84,7 @@ static int its_pci_msi_prepare(struct irq_domain *domain, struct device *dev, pci_for_each_dma_alias(pdev, its_get_pci_alias, &dev_alias); /* ITS specific DeviceID, as the core ITS ignores dev. */ - info->scratchpad[0].ul = dev_alias.dev_id; + info->scratchpad[0].ul = pci_msi_domain_get_msi_rid(domain, pdev); return msi_info->ops->msi_prepare(domain->parent, dev, dev_alias.count, info); diff --git a/drivers/irqchip/irq-gic-v3-its-platform-msi.c b/drivers/irqchip/irq-gic-v3-its-platform-msi.c index 960a8166a6c0..470b4aa7d62c 100644 --- a/drivers/irqchip/irq-gic-v3-its-platform-msi.c +++ b/drivers/irqchip/irq-gic-v3-its-platform-msi.c @@ -29,13 +29,25 @@ static int its_pmsi_prepare(struct irq_domain *domain, struct device *dev, { struct msi_domain_info *msi_info; u32 dev_id; - int ret; + int ret, index = 0; msi_info = msi_get_domain_info(domain->parent); /* Suck the DeviceID out of the msi-parent property */ - ret = of_property_read_u32_index(dev->of_node, "msi-parent", - 1, &dev_id); + do { + struct of_phandle_args args; + + ret = of_parse_phandle_with_args(dev->of_node, + "msi-parent", "#msi-cells", + index, &args); + if (args.np == irq_domain_get_of_node(domain)) { + if (WARN_ON(args.args_count != 1)) + return -EINVAL; + dev_id = args.args[0]; + break; + } + } while (!ret); + if (ret) return ret; diff --git a/drivers/of/irq.c b/drivers/of/irq.c index 55317fa9c9dc..0baf626da56a 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -579,6 +579,180 @@ err: } } +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); + + 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; + 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 + 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; +} + +/** + * of_msi_map_rid - Map a MSI requester ID for a device. + * @dev: device for which the mapping is to be done. + * @msi_np: device node of the expected msi controller. + * @rid_in: unmapped MSI requester ID for the device. + * + * Walk up the device hierarchy looking for devices with a "msi-map" + * property. If found, apply the mapping to @rid_in. + * + * Returns the mapped MSI requester ID. + */ +u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in) +{ + return __of_msi_map_rid(dev, &msi_np, rid_in); +} + +static struct irq_domain *__of_get_msi_domain(struct device_node *np, + enum irq_domain_bus_token token) +{ + struct irq_domain *d; + + d = irq_find_matching_host(np, token); + if (!d) + d = irq_find_host(np); + + return d; +} + +/** + * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain + * @dev: device for which the mapping is to be done. + * @rid: Requester ID for the device. + * + * Walk up the device hierarchy looking for devices with a "msi-map" + * property. + * + * Returns: the MSI domain for this device (or NULL on failure) + */ +struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 rid) +{ + struct device_node *np = NULL; + + __of_msi_map_rid(dev, &np, rid); + return __of_get_msi_domain(np, DOMAIN_BUS_PCI_MSI); +} + +/** + * of_msi_get_domain - Use msi-parent to find the relevant MSI domain + * @dev: device for which the domain is requested + * @np: device node for @dev + * @token: bus type for this domain + * + * Parse the msi-parent property (both the simple and the complex + * versions), and returns the corresponding MSI domain. + * + * Returns: the MSI domain for this device (or NULL on failure). + */ +struct irq_domain *of_msi_get_domain(struct device *dev, + struct device_node *np, + enum irq_domain_bus_token token) +{ + struct device_node *msi_np; + struct irq_domain *d; + + /* Check for a single msi-parent property */ + msi_np = of_parse_phandle(np, "msi-parent", 0); + if (msi_np && !of_property_read_bool(msi_np, "#msi-cells")) { + d = __of_get_msi_domain(msi_np, token); + if (!d) + of_node_put(msi_np); + return d; + } + + if (token == DOMAIN_BUS_PLATFORM_MSI) { + /* Check for the complex msi-parent version */ + struct of_phandle_args args; + int index = 0; + + while (!of_parse_phandle_with_args(np, "msi-parent", + "#msi-cells", + index, &args)) { + d = __of_get_msi_domain(args.np, token); + if (d) + return d; + + of_node_put(args.np); + index++; + } + } + + return NULL; +} + /** * of_msi_configure - Set the msi_domain field of a device * @dev: device structure to associate with an MSI irq domain @@ -586,15 +760,6 @@ err: */ void of_msi_configure(struct device *dev, struct device_node *np) { - struct device_node *msi_np; - struct irq_domain *d; - - msi_np = of_parse_phandle(np, "msi-parent", 0); - if (!msi_np) - return; - - d = irq_find_matching_host(msi_np, DOMAIN_BUS_PLATFORM_MSI); - if (!d) - d = irq_find_host(msi_np); - dev_set_msi_domain(dev, d); + dev_set_msi_domain(dev, + of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI)); } diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index ddd59fe786f8..4cd6f3abcecf 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "pci.h" @@ -1327,4 +1328,52 @@ struct irq_domain *pci_msi_create_default_irq_domain(struct fwnode_handle *fwnod return domain; } + +static int get_msi_id_cb(struct pci_dev *pdev, u16 alias, void *data) +{ + u32 *pa = data; + + *pa = alias; + return 0; +} +/** + * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID) + * @domain: The interrupt domain + * @pdev: The PCI device. + * + * The RID for a device is formed from the alias, with a firmware + * supplied mapping applied + * + * Returns: The RID. + */ +u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev) +{ + struct device_node *of_node; + u32 rid = 0; + + pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); + + of_node = irq_domain_get_of_node(domain); + if (of_node) + rid = of_msi_map_rid(&pdev->dev, of_node, rid); + + return rid; +} + +/** + * pci_msi_get_device_domain - Get the MSI domain for a given PCI device + * @pdev: The PCI device + * + * Use the firmware data to find a device-specific MSI domain + * (i.e. not one that is ste as a default). + * + * Returns: The coresponding MSI domain or NULL if none has been found. + */ +struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) +{ + u32 rid = 0; + + pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid); + return of_msi_map_get_device_domain(&pdev->dev, rid); +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ diff --git a/drivers/pci/of.c b/drivers/pci/of.c index 2e99a500cb83..e112da11630e 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include "pci.h" @@ -64,27 +65,25 @@ struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus) struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus) { #ifdef CONFIG_IRQ_DOMAIN - struct device_node *np; struct irq_domain *d; if (!bus->dev.of_node) return NULL; /* Start looking for a phandle to an MSI controller. */ - np = of_parse_phandle(bus->dev.of_node, "msi-parent", 0); + d = of_msi_get_domain(&bus->dev, bus->dev.of_node, DOMAIN_BUS_PCI_MSI); + if (d) + return d; /* * If we don't have an msi-parent property, look for a domain * directly attached to the host bridge. */ - if (!np) - np = bus->dev.of_node; - - d = irq_find_matching_host(np, DOMAIN_BUS_PCI_MSI); + d = irq_find_matching_host(bus->dev.of_node, DOMAIN_BUS_PCI_MSI); if (d) return d; - return irq_find_host(np); + return irq_find_host(bus->dev.of_node); #else return NULL; #endif diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 8361d27e5eca..f14a970b61fa 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1622,15 +1622,48 @@ static void pci_init_capabilities(struct pci_dev *dev) pci_enable_acs(dev); } +/* + * This is the equivalent of pci_host_bridge_msi_domain that acts on + * devices. Firmware interfaces that can select the MSI domain on a + * per-device basis should be called from here. + */ +static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev) +{ + struct irq_domain *d; + + /* + * If a domain has been set through the pcibios_add_device + * callback, then this is the one (platform code knows best). + */ + d = dev_get_msi_domain(&dev->dev); + if (d) + return d; + + /* + * Let's see if we have a firmware interface able to provide + * the domain. + */ + d = pci_msi_get_device_domain(dev); + if (d) + return d; + + return NULL; +} + static void pci_set_msi_domain(struct pci_dev *dev) { + struct irq_domain *d; + /* - * If no domain has been set through the pcibios_add_device - * callback, inherit the default from the bus device. + * If the platform or firmware interfaces cannot supply a + * device-specific MSI domain, then inherit the default domain + * from the host bridge itself. */ - if (!dev_get_msi_domain(&dev->dev)) - dev_set_msi_domain(&dev->dev, - dev_get_msi_domain(&dev->bus->dev)); + d = pci_dev_msi_domain(dev); + if (!d) + d = dev_get_msi_domain(&dev->bus->dev); + + dev_set_msi_domain(&dev->dev, d); } void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) diff --git a/include/linux/msi.h b/include/linux/msi.h index 32a24b9a9556..0b4460374020 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -294,6 +294,13 @@ irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev, struct msi_desc *desc); int pci_msi_domain_check_cap(struct irq_domain *domain, struct msi_domain_info *info, struct device *dev); +u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev); +struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev); +#else +static inline struct irq_domain *pci_msi_get_device_domain(struct pci_dev *pdev) +{ + return NULL; +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ #endif /* LINUX_MSI_H */ diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h index 4bcbd586a672..65d969246a4d 100644 --- a/include/linux/of_irq.h +++ b/include/linux/of_irq.h @@ -46,6 +46,11 @@ extern int of_irq_get(struct device_node *dev, int index); extern int of_irq_get_byname(struct device_node *dev, const char *name); extern int of_irq_to_resource_table(struct device_node *dev, struct resource *res, int nr_irqs); +extern struct irq_domain *of_msi_get_domain(struct device *dev, + struct device_node *np, + enum irq_domain_bus_token token); +extern struct irq_domain *of_msi_map_get_device_domain(struct device *dev, + u32 rid); #else static inline int of_irq_count(struct device_node *dev) { @@ -64,6 +69,17 @@ static inline int of_irq_to_resource_table(struct device_node *dev, { return 0; } +static inline struct irq_domain *of_msi_get_domain(struct device *dev, + struct device_node *np, + enum irq_domain_bus_token token) +{ + return NULL; +} +static inline struct irq_domain *of_msi_map_get_device_domain(struct device *dev, + u32 rid) +{ + return NULL; +} #endif #if defined(CONFIG_OF) @@ -75,6 +91,7 @@ static inline int of_irq_to_resource_table(struct device_node *dev, extern unsigned int irq_of_parse_and_map(struct device_node *node, int index); extern struct device_node *of_irq_find_parent(struct device_node *child); extern void of_msi_configure(struct device *dev, struct device_node *np); +u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in); #else /* !CONFIG_OF */ static inline unsigned int irq_of_parse_and_map(struct device_node *dev, @@ -87,6 +104,12 @@ static inline void *of_irq_find_parent(struct device_node *child) { return NULL; } + +static inline u32 of_msi_map_rid(struct device *dev, + struct device_node *msi_np, u32 rid_in) +{ + return rid_in; +} #endif /* !CONFIG_OF */ #endif /* __OF_IRQ_H */