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powerpc/pci: Initialize msi_addr_mask for OF-created PCI devices

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Recent changes replaced the use of no_64bit_msi with msi_addr_mask.  As a
result, msi_addr_mask is now expected to be initialized to DMA_BIT_MASK(64)
when a pci_dev is set up. However, this initialization was missed on
powerpc due to differences in the device initialization path compared to
other (x86) architecture. Due to this, now PCI device probe method fails on
powerpc system.

On powerpc systems, struct pci_dev instances are created from device tree
nodes via of_create_pci_dev(). Because msi_addr_mask was not initialized
there, it remained zero. Later, during MSI setup, msi_verify_entries()
validates the programmed MSI address against pdev->msi_addr_mask. Since the
mask was not set correctly, the validation fails, causing PCI driver probe
failures for devices on powerpc systems.

Initialize pdev->msi_addr_mask to DMA_BIT_MASK(64) in of_create_pci_dev()
so that MSI address validation succeeds and device probe works as expected.

Fixes: 386ced19e9 ("PCI/MSI: Convert the boolean no_64bit_msi flag to a DMA address mask")
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Tested-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Vivian Wang <wangruikang@iscas.ac.cn>
Acked-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260220070239.1693303-2-nilay@linux.ibm.com
This commit is contained in:
Nilay Shroff 2026-02-20 12:32:27 +05:30 • committed by Bjorn Helgaas
parent 6de23f81a5
commit 2185904ff8
1 changed files with 7 additions and 0 deletions
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7
arch/powerpc/kernel/pci_of_scan.c
View file

@ -212,6 +212,13 @@ struct pci_dev *of_create_pci_dev(struct device_node *node,
dev->error_state = pci_channel_io_normal;
dev->dma_mask = 0xffffffff;
/*
* Assume 64-bit addresses for MSI initially. Will be changed to 32-bit
* if MSI (rather than MSI-X) capability does not have
* PCI_MSI_FLAGS_64BIT. Can also be overridden by driver.
*/
dev->msi_addr_mask = DMA_BIT_MASK(64);
/* Early fixups, before probing the BARs */
pci_fixup_device(pci_fixup_early, dev);