From f294a5fd34db564108a16166d891634a3cb25c68 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ilpo=20J=C3=A4rvinen?= Date: Fri, 17 Oct 2025 14:09:03 +0300 Subject: [PATCH] MIPS: Malta: Use pcibios_align_resource() to block io range MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit According to Maciej W. Rozycki , the mips_pcibios_init() for malta adjusts root bus IO resource start address to prevent interfering with PIIX4 I/O cycle decoding. Adjusting lower bound leaves PIIX4 IO resources outside of the root bus resource and assign_fixed_resource_on_bus() does not link the resources into the resource tree. Prior to commit ae81aad5c2e1 ("MIPS: PCI: Use pci_enable_resources()") the arch specific pcibios_enable_resources() did not check if the resources were assigned which diverges from what PCI core checks, effectively hiding the PIIX4 IO resources were not properly within the resource tree. After starting to use pcibios_enable_resources() from PCI core, enabling PIIX4 fails: ata_piix 0000:00:0a.1: BAR 0 [io 0x01f0-0x01f7]: not claimed; can't enable device ata_piix 0000:00:0a.1: probe with driver ata_piix failed with error -22 MIPS PCI code already has support for enforcing lower bounds using PCIBIOS_MIN_IO in pcibios_align_resource() without altering the IO window start address itself. Make malta PCI code too to use PCIBIOS_MIN_IO. Fixes: ae81aad5c2e1 ("MIPS: PCI: Use pci_enable_resources()") Reported-by: Guenter Roeck Link: https://lore.kernel.org/linux-pci/9085ab12-1559-4462-9b18-f03dcb9a4088@roeck-us.net/ Suggested-by: Maciej W. Rozycki Link: https://lore.kernel.org/linux-pci/alpine.DEB.2.21.2510132229120.39634@angie.orcam.me.uk/ Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Tested-by: Guenter Roeck Tested-by: Maciej W. Rozycki Acked-by: Thomas Bogendoerfer Link: https://patch.msgid.link/20251017110903.1973-1-ilpo.jarvinen@linux.intel.com --- arch/mips/pci/pci-malta.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/mips/pci/pci-malta.c b/arch/mips/pci/pci-malta.c index 6aefdf20ca05..2e35aeba45bc 100644 --- a/arch/mips/pci/pci-malta.c +++ b/arch/mips/pci/pci-malta.c @@ -230,8 +230,7 @@ void __init mips_pcibios_init(void) } /* PIIX4 ACPI starts at 0x1000 */ - if (controller->io_resource->start < 0x00001000UL) - controller->io_resource->start = 0x00001000UL; + PCIBIOS_MIN_IO = 0x1000; iomem_resource.end &= 0xfffffffffULL; /* 64 GB */ ioport_resource.end = controller->io_resource->end; -- 2.47.3