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powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias

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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: 63a72284b1 ("powerpc/pci: Assign fixed PHB number based on device-tree properties")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220706102148.5060-2-pali@kernel.org
This commit is contained in:
Pali Rohár 2022-07-06 12:21:48 +02:00 committed by Michael Ellerman
parent d20c96deb3
commit 0fe1e96fef
1 changed files with 19 additions and 8 deletions
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27
arch/powerpc/kernel/pci-common.c
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@ -75,16 +75,30 @@ void __init set_pci_dma_ops(const struct dma_map_ops *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;
}
@ -96,10 +110,7 @@ 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);