From 3758a191116f110a503a0c6cb7ce89bc81841baa Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Thu, 15 Feb 2018 15:07:39 -0600 Subject: [PATCH] sparc/PCI: Stop reserving System ROM and Video ROM in PCI space Previously, pci_register_legacy_regions() reserved PCI address space under every PCI host bridge for the System ROM and the Video ROM, but these regions are not part of PCI address space. Previously, pci_register_legacy_regions() reserved the following areas of PCI address space under every PCI host bridge: [bus 0xa0000-0xbffff] Video RAM area (VGA frame buffer) [bus 0xc0000-0xc7fff] Video ROM [bus 0xf0000-0xfffff] System ROM It does need to reserve the [bus 0xa0000-0xbffff] region (at least if there's a possibility of a VGA device below the bridge) because VGA devices can respond to that even if they don't describe it with a BAR. But the Video ROM and System ROM areas don't seem necessary because they are not areas that legacy PCI devices respond to. They appear to be copied from x86, where they describe areas of system memory that depend on BIOS conventions. On x86, BIOS copies the option ROM of the primary VGA device to RAM at 0xc0000, and the 0xf0000-0xfffff region is reserved for the motherboard BIOS. Neither of these things applies to sparc. Stop reserving the System ROM and Video ROM regions in PCI space. Signed-off-by: Bjorn Helgaas Acked-by: David S. Miller --- arch/sparc/kernel/pci_common.c | 20 -------------------- 1 file changed, 20 deletions(-) diff --git a/arch/sparc/kernel/pci_common.c b/arch/sparc/kernel/pci_common.c index 14fa74f..38d46bc 100644 --- a/arch/sparc/kernel/pci_common.c +++ b/arch/sparc/kernel/pci_common.c @@ -344,26 +344,6 @@ static void pci_register_legacy_regions(struct resource *io_res, p->end = p->start + 0x1ffffUL; p->flags = IORESOURCE_BUSY; request_resource(mem_res, p); - - p = kzalloc(sizeof(*p), GFP_KERNEL); - if (!p) - return; - - p->name = "System ROM"; - p->start = mem_res->start + 0xf0000UL; - p->end = p->start + 0xffffUL; - p->flags = IORESOURCE_BUSY; - request_resource(mem_res, p); - - p = kzalloc(sizeof(*p), GFP_KERNEL); - if (!p) - return; - - p->name = "Video ROM"; - p->start = mem_res->start + 0xc0000UL; - p->end = p->start + 0x7fffUL; - p->flags = IORESOURCE_BUSY; - request_resource(mem_res, p); } static void pci_register_iommu_region(struct pci_pbm_info *pbm) -- 2.7.4