This is a note to let you know that I've just added the patch titled powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-pci-prefer-pci-domain-assignment-via-dt-linu.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b63cf8536099ac80b21508367bed19d742fcf266 Author: Pali Rohár <pali@xxxxxxxxxx> Date: Wed Jul 6 12:21:48 2022 +0200 powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias [ Upstream commit 0fe1e96fef0a5c53b4c0d1500d356f3906000f81 ] Other Linux architectures use DT property 'linux,pci-domain' for specifying fixed PCI domain of PCI controller specified in Device-Tree. And lot of Freescale powerpc boards have defined numbered pci alias in Device-Tree for every PCIe controller which number specify preferred PCI domain. So prefer usage of DT property 'linux,pci-domain' (via function of_get_pci_domain_nr()) and DT pci alias (via function of_alias_get_id()) on powerpc architecture for assigning PCI domain to PCI controller. Fixes: 63a72284b159 ("powerpc/pci: Assign fixed PHB number based on device-tree properties") Signed-off-by: Pali Rohár <pali@xxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220706102148.5060-2-pali@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 74bec5498972..decf78f34419 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -79,16 +79,30 @@ EXPORT_SYMBOL(get_pci_dma_ops); static int get_phb_number(struct device_node *dn) { int ret, phb_id = -1; - u32 prop_32; u64 prop; /* * Try fixed PHB numbering first, by checking archs and reading - * the respective device-tree properties. Firstly, try powernv by - * reading "ibm,opal-phbid", only present in OPAL environment. + * the respective device-tree properties. Firstly, try reading + * standard "linux,pci-domain", then try reading "ibm,opal-phbid" + * (only present in powernv OPAL environment), then try device-tree + * alias and as the last try to use lower bits of "reg" property. */ - ret = of_property_read_u64(dn, "ibm,opal-phbid", &prop); + ret = of_get_pci_domain_nr(dn); + if (ret >= 0) { + prop = ret; + ret = 0; + } + if (ret) + ret = of_property_read_u64(dn, "ibm,opal-phbid", &prop); + if (ret) + ret = of_alias_get_id(dn, "pci"); + if (ret >= 0) { + prop = ret; + ret = 0; + } if (ret) { + u32 prop_32; ret = of_property_read_u32_index(dn, "reg", 1, &prop_32); prop = prop_32; } @@ -100,10 +114,7 @@ static int get_phb_number(struct device_node *dn) if ((phb_id >= 0) && !test_and_set_bit(phb_id, phb_bitmap)) return phb_id; - /* - * If not pseries nor powernv, or if fixed PHB numbering tried to add - * the same PHB number twice, then fallback to dynamic PHB numbering. - */ + /* If everything fails then fallback to dynamic PHB numbering. */ phb_id = find_first_zero_bit(phb_bitmap, MAX_PHBS); BUG_ON(phb_id >= MAX_PHBS); set_bit(phb_id, phb_bitmap);