From b531566e4dced7566dfa2e4925ec8b6a8cb7806b Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 8 Oct 2015 15:10:47 -0700 Subject: Docs: dt: Add PCI MSI map bindings Currently msi-parent is used by a few bindings to describe the relationship between a PCI root complex and a single MSI controller, but this property does not have a generic binding document. Additionally, msi-parent is insufficient to describe more complex relationships between MSI controllers and devices under a root complex, where devices may be able to target multiple MSI controllers, or where MSI controllers use (non-probeable) sideband information to distinguish devices. This patch adds a generic binding for mapping PCI devices to MSI controllers. This document covers msi-parent, and a new msi-map property (specific to PCI*) which may be used to map devices (identified by their Requester ID) to sideband data for each MSI controller that they may target. Acked-by: Marc Zyngier Acked-by: Rob Herring Signed-off-by: Mark Rutland Signed-off-by: David Daney Signed-off-by: Marc Zyngier --- Documentation/devicetree/bindings/pci/pci-msi.txt | 220 ++++++++++++++++++++++ 1 file changed, 220 insertions(+) create mode 100644 Documentation/devicetree/bindings/pci/pci-msi.txt 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>; + }; +}; -- cgit v1.2.3 From 8db02d8b4089fa8098a170738e8ae7939aa8ae7a Mon Sep 17 00:00:00 2001 From: David Daney Date: Thu, 8 Oct 2015 15:10:48 -0700 Subject: of/irq: Add new function of_msi_map_rid() The device tree property "msi-map" specifies how to create the PCI requester id used in some MSI controllers. Add a new function of_msi_map_rid() that finds the msi-map property and applies its translation to a given requester id. Reviewed-by: Marc Zyngier Acked-by: Rob Herring Signed-off-by: David Daney Signed-off-by: Marc Zyngier --- drivers/of/irq.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_irq.h | 7 +++++ 2 files changed, 91 insertions(+) diff --git a/drivers/of/irq.c b/drivers/of/irq.c index 55317fa9c9dc..c90bd4ec3183 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -598,3 +598,87 @@ void of_msi_configure(struct device *dev, struct device_node *np) d = irq_find_host(msi_np); dev_set_msi_domain(dev, d); } + +/** + * 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) +{ + struct device *parent_dev; + struct device_node *msi_controller_node; + 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 && + msi_np == msi_controller_node; + + 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; +} diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h index 4bcbd586a672..8cd9334e5731 100644 --- a/include/linux/of_irq.h +++ b/include/linux/of_irq.h @@ -75,6 +75,7 @@ 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 +88,12 @@ 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 */ -- cgit v1.2.3 From b6eec9b717d4dcb39ef024b8a3b619a32468b01e Mon Sep 17 00:00:00 2001 From: David Daney Date: Thu, 8 Oct 2015 15:10:49 -0700 Subject: PCI/MSI: Add helper function pci_msi_domain_get_msi_rid(). Add pci_msi_domain_get_msi_rid() to return the MSI requester id (RID). Initially needed by gic-v3 based systems. It will be used by follow on patch to drivers/irqchip/irq-gic-v3-its-pci-msi.c Initially supports mapping the RID via OF device tree. In the future, this could be extended to use ACPI _IORT tables as well. Reviewed-by: Marc Zyngier Acked-by: Bjorn Helgaas Signed-off-by: David Daney Signed-off-by: Marc Zyngier --- drivers/pci/msi.c | 32 ++++++++++++++++++++++++++++++++ include/linux/msi.h | 1 + 2 files changed, 33 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index ddd59fe786f8..5ab5c4f8dcb0 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "pci.h" @@ -1327,4 +1328,35 @@ 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; +} #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ diff --git a/include/linux/msi.h b/include/linux/msi.h index 32a24b9a9556..87723751054d 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -294,6 +294,7 @@ 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); #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */ #endif /* LINUX_MSI_H */ -- cgit v1.2.3 From ccf91e68a4357e7b65a3f1f13f8af2b767213575 Mon Sep 17 00:00:00 2001 From: David Daney Date: Thu, 8 Oct 2015 15:10:50 -0700 Subject: irqchip/gic-v3-its: Add handling of PCI requester id. Replace open coded generation PCI/MSI requester id with call to the new function pci_msi_domain_get_msi_rid() which applies the "msi-map" to the id value. Reviewed-by: Marc Zyngier Signed-off-by: David Daney Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-its-pci-msi.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) 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); -- cgit v1.2.3 From 48ae34fb39b0c0cfc76275e844fba5b0b04fa49e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 18 Sep 2015 14:07:40 +0100 Subject: of/irq: Add support code for multi-parent version of "msi-parent" Since 126b16e2ad98 ("Docs: dt: add generic MSI bindings"), the definition of "msi-parent" has evolved, while maintaining some degree of compatibility. It can now express multiple MSI controllers as parents, as well as some sideband data being communicated to the controller. This patch adds the parsing of the property, iterating over the multiple parents until a suitable irqdomain is found. It can also fallback to the original parsing if the old binding is detected. This support code gets used in the subsequent patches. Suggested-by: Robin Murphy Acked-by: Rob Herring Signed-off-by: Marc Zyngier --- drivers/of/irq.c | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_irq.h | 9 ++++++++ 2 files changed, 68 insertions(+) diff --git a/drivers/of/irq.c b/drivers/of/irq.c index c90bd4ec3183..62cfdc2c86ac 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -682,3 +682,62 @@ u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in) return rid_out; } + +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_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; +} diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h index 8cd9334e5731..62ae6edecfd5 100644 --- a/include/linux/of_irq.h +++ b/include/linux/of_irq.h @@ -46,6 +46,9 @@ 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); #else static inline int of_irq_count(struct device_node *dev) { @@ -64,6 +67,12 @@ 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; +} #endif #if defined(CONFIG_OF) -- cgit v1.2.3 From 61c08240a103000b75dcf7ef2cf03d552aa91fa3 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 18 Sep 2015 14:07:40 +0100 Subject: of/irq: Use of_msi_get_domain instead of open-coded "msi-parent" parsing Now that we have a function that implements the complexity of the "msi-parent" property parsing, switch to that. Acked-by: Rob Herring Signed-off-by: Marc Zyngier --- drivers/of/irq.c | 31 +++++++++++-------------------- 1 file changed, 11 insertions(+), 20 deletions(-) diff --git a/drivers/of/irq.c b/drivers/of/irq.c index 62cfdc2c86ac..89ebc612293d 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -579,26 +579,6 @@ err: } } -/** - * of_msi_configure - Set the msi_domain field of a device - * @dev: device structure to associate with an MSI irq domain - * @np: device node for that device - */ -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); -} - /** * of_msi_map_rid - Map a MSI requester ID for a device. * @dev: device for which the mapping is to be done. @@ -741,3 +721,14 @@ struct irq_domain *of_msi_get_domain(struct device *dev, return NULL; } + +/** + * of_msi_configure - Set the msi_domain field of a device + * @dev: device structure to associate with an MSI irq domain + * @np: device node for that device + */ +void of_msi_configure(struct device *dev, struct device_node *np) +{ + dev_set_msi_domain(dev, + of_msi_get_domain(dev, np, DOMAIN_BUS_PLATFORM_MSI)); +} -- cgit v1.2.3 From c8d175883e0db09ce94b8b47bb2432b787149a6b Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 18 Sep 2015 14:07:40 +0100 Subject: PCI/MSI: Use of_msi_get_domain instead of open-coded "msi-parent" parsing Now that we have a function that implements the complexity of the "msi-parent" property parsing, switch to that. Acked-by: Rob Herring Acked-by: Bjorn Helgaas Signed-off-by: Marc Zyngier --- drivers/pci/of.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) 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 -- cgit v1.2.3 From deac7fc1c87f24099d7e15d8b662446497f57465 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 18 Sep 2015 14:07:40 +0100 Subject: irqchip/gic-v3-its: Parse new version of msi-parent property Now that 126b16e2ad98 ("Docs: dt: add generic MSI bindings") has made it into the tree, the time has come to get rid of the old hack, and to parse msi-parent in its full glory. Acked-by: Rob Herring Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-its-platform-msi.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) 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; -- cgit v1.2.3 From a251b263346e38b9fafebeb49ada9ce894882616 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 1 Oct 2015 17:05:45 +0100 Subject: of/irq: Split of_msi_map_rid to reuse msi-map lookup The msi-map property is also used to identify the MSI controller as a form of grown-up msi-parent property. Looking it up is complicated enough, and since of_msi_map_rid already implements this, let's turn it into an internal utility function. We'll put that to good use later on. Acked-by: Rob Herring Signed-off-by: Marc Zyngier --- drivers/of/irq.c | 43 ++++++++++++++++++++++++++++--------------- 1 file changed, 28 insertions(+), 15 deletions(-) diff --git a/drivers/of/irq.c b/drivers/of/irq.c index 89ebc612293d..ed64d98807f9 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -579,21 +579,12 @@ err: } } -/** - * 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) +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; @@ -643,9 +634,15 @@ u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in) msi_controller_node = of_find_node_by_phandle(phandle); - matched = masked_rid >= rid_base && - masked_rid < rid_base + rid_len && - msi_np == msi_controller_node; + 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); @@ -663,6 +660,22 @@ u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in) 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) { -- cgit v1.2.3 From 82b9b4243c6d99d9e38087fa89183aa7479185e9 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 2 Oct 2015 14:38:55 +0100 Subject: of/irq: Use the msi-map property to provide device-specific MSI domain While msi-parent is used to point to the MSI controller that works for all the devices behind a root complex, it doesn't allow configurations where each individual device can be routed to a separate MSI controller. The msi-map property provides this flexibility (and much more), so let's add a utility function that parses it, and return the corresponding MSI domain. Acked-by: Rob Herring Signed-off-by: Marc Zyngier --- drivers/of/irq.c | 18 ++++++++++++++++++ include/linux/of_irq.h | 7 +++++++ 2 files changed, 25 insertions(+) diff --git a/drivers/of/irq.c b/drivers/of/irq.c index ed64d98807f9..0baf626da56a 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -688,6 +688,24 @@ static struct irq_domain *__of_get_msi_domain(struct device_node *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 diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h index 62ae6edecfd5..65d969246a4d 100644 --- a/include/linux/of_irq.h +++ b/include/linux/of_irq.h @@ -49,6 +49,8 @@ extern int of_irq_to_resource_table(struct device_node *dev, 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) { @@ -73,6 +75,11 @@ static inline struct irq_domain *of_msi_get_domain(struct device *dev, { 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) -- cgit v1.2.3 From 098259eb16675a83e1d6ea31e06dc3ec152810a2 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 2 Oct 2015 10:19:32 +0100 Subject: PCI: Add per-device MSI domain hook So far, we have considered that the MSI domain for a device was either set via the architecture-dependent pcibios implementation or inherited from the host bridge. As we're about to break that assumption, add pci_dev_msi_domain which is the equivalent of pci_host_bridge_msi_domain, but for a single device. Other than moving things around a bit, this patch on its own has no effect. Acked-by: Rob Herring Acked-by: Bjorn Helgaas Signed-off-by: Marc Zyngier --- drivers/pci/probe.c | 35 ++++++++++++++++++++++++++++++----- 1 file changed, 30 insertions(+), 5 deletions(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 8361d27e5eca..7c333f8c2327 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1622,15 +1622,40 @@ 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; + + 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) -- cgit v1.2.3 From 54fa97eeb9e22b47d68b67ee00987afa7fbc2178 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 2 Oct 2015 14:43:06 +0100 Subject: PCI/MSI: Allow the MSI domain to be device-specific So far, we've always considered that for a given PCI device, its MSI controller was either set by the architecture-specific pcibios hook, or simply inherited from the host bridge. This doesn't cover things like firmware-defined topologies like msi-map (DT) or IORT (ACPI), which can provide information about which MSI controller to use on a per-device basis. This patch adds the necessary hook into the MSI code to allow this feature, and provides the msi-map functionnality as a first implementation. Acked-by: Rob Herring Acked-by: Bjorn Helgaas Signed-off-by: Marc Zyngier --- drivers/pci/msi.c | 17 +++++++++++++++++ drivers/pci/probe.c | 8 ++++++++ include/linux/msi.h | 6 ++++++ 3 files changed, 31 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 5ab5c4f8dcb0..4cd6f3abcecf 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -1359,4 +1359,21 @@ u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev) 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/probe.c b/drivers/pci/probe.c index 7c333f8c2327..f14a970b61fa 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1639,6 +1639,14 @@ static struct irq_domain *pci_dev_msi_domain(struct pci_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; } diff --git a/include/linux/msi.h b/include/linux/msi.h index 87723751054d..0b4460374020 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -295,6 +295,12 @@ irq_hw_number_t pci_msi_domain_calc_hwirq(struct pci_dev *dev, 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 */ -- cgit v1.2.3