On 4/19/23 16:11, Rob Herring wrote:
Ok, Both of_msi_map_id() and iort_msi_map_id() will return input rid for a pure DT system. I can drop this change.On Tue, Apr 18, 2023 at 09:19:53PM -0700, Lizhi Hou wrote:The PCI endpoint device such as Xilinx Alveo PCI card maps the register spaces from multiple hardware peripherals to its PCI BAR. Normally, the PCI core discovers devices and BARs using the PCI enumeration process. There is no infrastructure to discover the hardware peripherals that are present in a PCI device, and which can be accessed through the PCI BARs. For Alveo PCI card, the card firmware provides a flattened device tree to describe the hardware peripherals on its BARs. The Alveo card driver can load this flattened device tree and leverage device tree framework to generate platform devices for the hardware peripherals eventually. Apparently, the device tree framework requires a device tree node for the PCI device. Thus, it can generate the device tree nodes for hardware peripherals underneath. Because PCI is self discoverable bus, there might not be a device tree node created for PCI devices. This patch is to add support to generate device tree node for PCI devices. Added a kernel option. When the option is turned on, the kernel will generate device tree nodes for PCI bridges unconditionally. Initially, the basic properties are added for the dynamically generated device tree nodes. Signed-off-by: Lizhi Hou <lizhi.hou@xxxxxxx> --- drivers/pci/Kconfig | 12 ++ drivers/pci/Makefile | 1 + drivers/pci/bus.c | 2 + drivers/pci/msi/irqdomain.c | 6 +- drivers/pci/of.c | 79 ++++++++++++++ drivers/pci/of_property.c | 212 ++++++++++++++++++++++++++++++++++++ drivers/pci/pci-driver.c | 3 +- drivers/pci/pci.h | 19 ++++ drivers/pci/remove.c | 1 + 9 files changed, 332 insertions(+), 3 deletions(-) create mode 100644 drivers/pci/of_property.c diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig index 9309f2469b41..24c3107c68cc 100644 --- a/drivers/pci/Kconfig +++ b/drivers/pci/Kconfig @@ -193,6 +193,18 @@ config PCI_HYPERV The PCI device frontend driver allows the kernel to import arbitrary PCI devices from a PCI backend to support PCI driver domains.+config PCI_DYNAMIC_OF_NODES+ bool "Create Devicetree nodes for PCI devices" + depends on OF + select OF_DYNAMIC + help + This option enables support for generating device tree nodes for some + PCI devices. Thus, the driver of this kind can load and overlay + flattened device tree for its downstream devices. + + Once this option is selected, the device tree nodes will be generated + for all PCI bridges. + choice prompt "PCI Express hierarchy optimization setting" default PCIE_BUS_DEFAULT diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile index 2680e4c92f0a..cc8b4e01e29d 100644 --- a/drivers/pci/Makefile +++ b/drivers/pci/Makefile @@ -32,6 +32,7 @@ obj-$(CONFIG_PCI_P2PDMA) += p2pdma.o obj-$(CONFIG_XEN_PCIDEV_FRONTEND) += xen-pcifront.o obj-$(CONFIG_VGA_ARB) += vgaarb.o obj-$(CONFIG_PCI_DOE) += doe.o +obj-$(CONFIG_PCI_DYNAMIC_OF_NODES) += of_property.o# Endpoint library must be initialized before its usersobj-$(CONFIG_PCI_ENDPOINT) += endpoint/ diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index 549c4bd5caec..89ef8c64bb22 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -341,6 +341,8 @@ void pci_bus_add_device(struct pci_dev *dev) */ pcibios_bus_add_device(dev); pci_fixup_device(pci_fixup_final, dev); + if (pci_is_bridge(dev)) + of_pci_make_dev_node(dev); pci_create_sysfs_dev_files(dev); pci_proc_attach_device(dev); pci_bridge_d3_update(dev); diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c index e33bcc872699..cd73d2250305 100644 --- a/drivers/pci/msi/irqdomain.c +++ b/drivers/pci/msi/irqdomain.c @@ -456,8 +456,10 @@ u32 pci_msi_domain_get_msi_rid(struct irq_domain *domain, struct pci_dev *pdev) pci_for_each_dma_alias(pdev, get_msi_id_cb, &rid);of_node = irq_domain_get_of_node(domain);- rid = of_node ? of_msi_map_id(&pdev->dev, of_node, rid) : - iort_msi_map_id(&pdev->dev, rid); + if (of_node && !of_node_check_flag(of_node, OF_DYNAMIC)) + rid = of_msi_map_id(&pdev->dev, of_node, rid); + else + rid = iort_msi_map_id(&pdev->dev, rid);Whether or not this works depends if the host bridge has an 'msi-map' or not. For a pure DT system, I think you need to drop this change. The behavior shouldn't change based on dynamic vs. static nodes.
This change is required. For dynamic generated node, we do not generate interrupt routing related properties. Thus we need to fallback to use pci_swizzle_interrupt_pin(). Generating interrupt routing related properties might be difficult. I think we can differ it to the future patches. Or just use pci_swizzle_interrupt_pin() which is much simpler.For this to work for all 3 cases, I think we need just: rid = of_msi_map_id(&pdev->dev, of_node, rid); // NOP if of_node is NULL rid = iort_msi_map_id(&pdev->dev, rid); // NOP if no IORT entry But I'm not really sure if that really works for ACPI or not.return rid;} diff --git a/drivers/pci/of.c b/drivers/pci/of.c index 196834ed44fe..42a5cfac2d34 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -469,6 +469,8 @@ static int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args * } else { /* We found a P2P bridge, check if it has a node */ ppnode = pci_device_to_OF_node(ppdev); + if (ppnode && of_node_check_flag(ppnode, OF_DYNAMIC)) + ppnode = NULL;Again, different behavior if dynamic. I'm not seeing why you need this change.
}/*@@ -599,6 +601,83 @@ int devm_of_pci_bridge_init(struct device *dev, struct pci_host_bridge *bridge) return pci_parse_request_of_pci_ranges(dev, bridge); }+#if IS_ENABLED(CONFIG_PCI_DYNAMIC_OF_NODES)+ +void of_pci_remove_node(struct pci_dev *pdev) +{ + struct device_node *np; + + np = pci_device_to_OF_node(pdev); + if (!np || !of_node_check_flag(np, OF_DYNAMIC)) + return; + pdev->dev.of_node = NULL; + + of_changeset_revert(np->data); + of_changeset_destroy(np->data); + of_node_put(np); +} + +void of_pci_make_dev_node(struct pci_dev *pdev) +{ + struct device_node *ppnode, *np = NULL; + const char *pci_type = "dev"; + struct of_changeset *cset; + const char *name; + int ret; + + /* + * If there is already a device tree node linked to this device, + * return immediately. + */ + if (pci_device_to_OF_node(pdev)) + return; + + /* Check if there is device tree node for parent device */ + if (!pdev->bus->self) + ppnode = pdev->bus->dev.of_node; + else + ppnode = pdev->bus->self->dev.of_node; + if (!ppnode) + return; + + if (pci_is_bridge(pdev)) + pci_type = "pci"; + + name = kasprintf(GFP_KERNEL, "%s@%x,%x", pci_type, + PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn)); + if (!name) + return; + + cset = kmalloc(sizeof(*cset), GFP_KERNEL); + if (!cset) + goto failed; + of_changeset_init(cset); + + np = of_changeset_create_node(ppnode, name, cset); + if (!np) + goto failed; + np->data = cset; + + ret = of_pci_add_properties(pdev, cset, np); + if (ret) + goto failed; + + ret = of_changeset_apply(cset); + if (ret) + goto failed; + + pdev->dev.of_node = np; + kfree(name); + + return; + +failed: + if (np) + of_node_put(np); + kfree(name); +} +#endif + #endif /* CONFIG_PCI *//**diff --git a/drivers/pci/of_property.c b/drivers/pci/of_property.c new file mode 100644 index 000000000000..3d8267aa96e2 --- /dev/null +++ b/drivers/pci/of_property.c @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2022, Advanced Micro Devices, Inc. + */ + +#include <linux/pci.h> +#include <linux/of.h> +#include <linux/bitfield.h> +#include <linux/bits.h> +#include "pci.h" + +#define OF_PCI_ADDRESS_CELLS 3 +#define OF_PCI_SIZE_CELLS 2 + +struct of_pci_addr_pair { + u32 phys_addr[OF_PCI_ADDRESS_CELLS]; + u32 size[OF_PCI_SIZE_CELLS]; +}; + +struct of_pci_range { + u32 child_addr[OF_PCI_ADDRESS_CELLS]; + u32 parent_addr[OF_PCI_ADDRESS_CELLS]; + u32 size[OF_PCI_SIZE_CELLS]; +}; + +#define OF_PCI_ADDR_SPACE_IO 0x1 +#define OF_PCI_ADDR_SPACE_MEM32 0x2 +#define OF_PCI_ADDR_SPACE_MEM64 0x3 + +#define OF_PCI_ADDR_FIELD_NONRELOC BIT(31) +#define OF_PCI_ADDR_FIELD_SS GENMASK(25, 24) +#define OF_PCI_ADDR_FIELD_PREFETCH BIT(30) +#define OF_PCI_ADDR_FIELD_BUS GENMASK(23, 16) +#define OF_PCI_ADDR_FIELD_DEV GENMASK(15, 11) +#define OF_PCI_ADDR_FIELD_FUNC GENMASK(10, 8) +#define OF_PCI_ADDR_FIELD_REG GENMASK(7, 0) + +#define OF_PCI_ADDR_HI GENMASK_ULL(63, 32) +#define OF_PCI_ADDR_LO GENMASK_ULL(31, 0) +#define OF_PCI_SIZE_HI GENMASK_ULL(63, 32) +#define OF_PCI_SIZE_LO GENMASK_ULL(31, 0) + +enum of_pci_prop_compatible { + PROP_COMPAT_PCI_VVVV_DDDD, + PROP_COMPAT_PCICLASS_CCSSPP, + PROP_COMPAT_PCICLASS_CCSS, + PROP_COMPAT_NUM, +}; + +static void of_pci_set_address(struct pci_dev *pdev, u32 *prop, u64 addr, + u32 reg_num, u32 flags, bool reloc) +{ + prop[0] = FIELD_PREP(OF_PCI_ADDR_FIELD_BUS, pdev->bus->number) | + FIELD_PREP(OF_PCI_ADDR_FIELD_DEV, PCI_SLOT(pdev->devfn)) | + FIELD_PREP(OF_PCI_ADDR_FIELD_FUNC, PCI_FUNC(pdev->devfn)); + prop[0] |= flags | reg_num; + if (!reloc) { + prop[0] |= OF_PCI_ADDR_FIELD_NONRELOC; + prop[1] = FIELD_GET(OF_PCI_ADDR_HI, addr); + prop[2] = FIELD_GET(OF_PCI_ADDR_LO, addr);No need for your own macros here. Use upper_32_bits() and lower_32_bits(). Same for size macros.
Ok, sure.
+ } +} + +static int of_pci_get_addr_flags(struct resource *res, u32 *flags) +{ + u32 ss; + + if (res->flags & IORESOURCE_IO) + ss = OF_PCI_ADDR_SPACE_IO; + else if (res->flags & IORESOURCE_MEM_64) + ss = OF_PCI_ADDR_SPACE_MEM64; + else if (res->flags & IORESOURCE_MEM) + ss = OF_PCI_ADDR_SPACE_MEM32; + else + return -EINVAL; + + *flags = 0; + if (res->flags & IORESOURCE_PREFETCH) + *flags |= OF_PCI_ADDR_FIELD_PREFETCH; + + *flags |= FIELD_PREP(OF_PCI_ADDR_FIELD_SS, ss); + + return 0; +} + +static int of_pci_prop_ranges(struct pci_dev *pdev, struct of_changeset *ocs, + struct device_node *np) +{ + struct of_pci_range *rp; + struct resource *res; + int i = 0, j, ret; + u64 val64; + u32 flags; + + rp = kcalloc(PCI_BRIDGE_RESOURCE_NUM, sizeof(*rp), GFP_KERNEL); + if (!rp) + return -ENOMEM; + + res = &pdev->resource[PCI_BRIDGE_RESOURCES]; + for (j = 0; j < PCI_BRIDGE_RESOURCE_NUM; j++) { + if (!resource_size(&res[j])) + continue; + + if (of_pci_get_addr_flags(&res[j], &flags)) + continue; + + val64 = res[j].start; + of_pci_set_address(pdev, rp[i].parent_addr, val64, 0, flags, + false); + memcpy(rp[i].child_addr, rp[i].parent_addr, + sizeof(rp[i].child_addr)); + + val64 = resource_size(&res[j]); + rp[i].size[0] = FIELD_GET(OF_PCI_SIZE_HI, val64); + rp[i].size[1] = FIELD_GET(OF_PCI_SIZE_LO, val64); + + i++; + } + + ret = of_changeset_add_prop_u32_array(ocs, np, "ranges", (u32 *)rp, + i * sizeof(*rp) / sizeof(u32)); + kfree(rp); + + return ret; +} + +static int of_pci_prop_reg(struct pci_dev *pdev, struct of_changeset *ocs, + struct device_node *np) +{ + struct of_pci_addr_pair *reg; + int i = 1, resno, ret = 0; + u32 flags, base_addr; + resource_size_t sz; + + reg = kcalloc(PCI_STD_NUM_BARS + 1, sizeof(*reg), GFP_KERNEL); + if (!reg) + return -ENOMEM; + + /* configuration space */ + of_pci_set_address(pdev, reg[0].phys_addr, 0, 0, 0, true); + + base_addr = PCI_BASE_ADDRESS_0; + for (resno = PCI_STD_RESOURCES; resno <= PCI_STD_RESOURCE_END; + resno++, base_addr += 4) { + sz = pci_resource_len(pdev, resno); + if (!sz) + continue; + + ret = of_pci_get_addr_flags(&pdev->resource[resno], &flags); + if (ret) + continue; + + of_pci_set_address(pdev, reg[i].phys_addr, 0, base_addr, flags, + true); + reg[i].size[0] = FIELD_GET(OF_PCI_SIZE_HI, (u64)sz); + reg[i].size[1] = FIELD_GET(OF_PCI_SIZE_LO, (u64)sz); + i++; + } + + ret = of_changeset_add_prop_u32_array(ocs, np, "reg", (u32 *)reg,I believe this should be 'assigned-addresses' rather than 'reg'. But the config space entry above does go in 'reg'.
Do you mean I need to add 'assigned-addresses' in this patch?For 'reg', it needs to have pairs for memory space or I/O space. Here is what I saw in IEEE1275:
"In the first such pair, the phys-addr component shall be the Configuration Space address of the beginning of the function's set of configuration registers (i.e. the rrrrrrrr field is zero) and the size component shall be zero. Each additional (phys-addr, size) pair shall specify the address of an addressable region of Memory Space or I/ O Space associated with the function. In these pairs, if the "n" bit of phys.hi is 0, reflecting a relocatable address, then phys.mid and phys.lo specify an address relative to the value of the associated base register. In general this value will be zero, specifying an address range corresponding directly to the hardware's. If the "n" bit of phys.hi is 1, reflecting a nonrelocatable address, then phys.mid and phys.hi specify an absolute PCI address."
+ i * sizeof(*reg) / sizeof(u32)); + kfree(reg); + + return ret; +} + +static int of_pci_prop_compatible(struct pci_dev *pdev, + struct of_changeset *ocs, + struct device_node *np) +{ + const char *compat_strs[PROP_COMPAT_NUM] = { 0 }; + int i, ret; + + compat_strs[PROP_COMPAT_PCI_VVVV_DDDD] = + kasprintf(GFP_KERNEL, "pci%x,%x", pdev->vendor, pdev->device); + compat_strs[PROP_COMPAT_PCICLASS_CCSSPP] = + kasprintf(GFP_KERNEL, "pciclass,%06x", pdev->class); + compat_strs[PROP_COMPAT_PCICLASS_CCSS] = + kasprintf(GFP_KERNEL, "pciclass,%04x", pdev->class >> 8); + + ret = of_changeset_add_prop_string_array(ocs, np, "compatible", + compat_strs, PROP_COMPAT_NUM); + for (i = 0; i < PROP_COMPAT_NUM; i++) + kfree(compat_strs[i]); + + return ret; +} + +int of_pci_add_properties(struct pci_dev *pdev, struct of_changeset *ocs, + struct device_node *np) +{ + int ret = 0; + + if (pci_is_bridge(pdev)) { + ret |= of_changeset_add_prop_string(ocs, np, "device_type", + "pci"); + ret |= of_changeset_add_prop_u32(ocs, np, "#address-cells", + OF_PCI_ADDRESS_CELLS); + ret |= of_changeset_add_prop_u32(ocs, np, "#size-cells", + OF_PCI_SIZE_CELLS); + ret |= of_pci_prop_ranges(pdev, ocs, np); + } + + ret |= of_pci_prop_reg(pdev, ocs, np); + ret |= of_pci_prop_compatible(pdev, ocs, np); + + /* + * The added properties will be released when the + * changeset is destroyed. + */ + return ret; +} diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 57ddcc59af30..9120ca63a82a 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -1634,7 +1634,8 @@ static int pci_dma_configure(struct device *dev) bridge = pci_get_host_bridge_device(to_pci_dev(dev));if (IS_ENABLED(CONFIG_OF) && bridge->parent &&- bridge->parent->of_node) { + bridge->parent->of_node && + !of_node_check_flag(bridge->parent->of_node, OF_DYNAMIC)) {Again, I don't think changing behavior for dynamic case is right. I haven't dug into what an ACPI+DT case would look like here. (Hint: someone that wants this merged can dig into that)
I think this is required. Without dynamic node, on pure DT system, has_acpi_companion() will return false. Then "ret" is 0 and the following iommu_device_use_default_domain() might be called.
With dynamic node, of_dma_configure() might return error because dma related properties are not generated. Thus, "ret" is none zero and the following iommu_device_use_default_domain() will be skipped.
Thanks, Lizhi
ret = of_dma_configure(dev, bridge->parent->of_node, true); } else if (has_acpi_companion(bridge)) { struct acpi_device *adev = to_acpi_device_node(bridge->fwnode); diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index d2c08670a20e..58df456e6c92 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -674,6 +674,25 @@ static inline int devm_of_pci_bridge_init(struct device *dev, struct pci_host_br#endif /* CONFIG_OF */ +struct of_changeset;+ +#ifdef CONFIG_PCI_DYNAMIC_OF_NODES +void of_pci_make_dev_node(struct pci_dev *pdev); +void of_pci_remove_node(struct pci_dev *pdev); +int of_pci_add_properties(struct pci_dev *pdev, struct of_changeset *ocs, + struct device_node *np); +#else +static inline void +of_pci_make_dev_node(struct pci_dev *pdev) +{ +} + +static inline void +of_pci_remove_node(struct pci_dev *pdev) +{ +} +#endif /* CONFIG_PCI_DYNAMIC_OF_NODES */ + #ifdef CONFIG_PCIEAER void pci_no_aer(void); void pci_aer_init(struct pci_dev *dev); diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index 0145aef1b930..1462f2d9b194 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -23,6 +23,7 @@ static void pci_stop_dev(struct pci_dev *dev) device_release_driver(&dev->dev); pci_proc_detach_device(dev); pci_remove_sysfs_dev_files(dev); + of_pci_remove_node(dev);pci_dev_assign_added(dev, false);} -- 2.34.1
