From 321ab6a5fab812658626aee6bce2617f8cfb3a55 Mon Sep 17 00:00:00 2001 From: Lennert Buytenhek Date: Sat, 25 Jun 2005 19:30:04 +0100 Subject: [PATCH] ARM: 2752/1: disable ixp2000 PCI I/O software workaround on chips that don't need it Patch from Lennert Buytenhek The later ixp2000 models don't need the PCI I/O workaround that we currently perform. Add a config option to disable the workaround, and panic on boot if a kernel without the workaround is booted on a buggy chip. As only pre-production ixp2000s need the workaround, the default is for it not to be configured in. Signed-off-by: Lennert Buytenhek Signed-off-by: Deepak Saxena Signed-off-by: Russell King --- include/asm-arm/arch-ixp2000/io.h | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'include/asm-arm/arch-ixp2000/io.h') diff --git a/include/asm-arm/arch-ixp2000/io.h b/include/asm-arm/arch-ixp2000/io.h index 5e56b47446e..3241cd6f077 100644 --- a/include/asm-arm/arch-ixp2000/io.h +++ b/include/asm-arm/arch-ixp2000/io.h @@ -17,16 +17,21 @@ #define IO_SPACE_LIMIT 0xffffffff #define __mem_pci(a) (a) -#define ___io(p) ((void __iomem *)((p)+IXP2000_PCI_IO_VIRT_BASE)) /* - * The IXP2400 before revision B0 asserts byte lanes for PCI I/O + * The A? revisions of the IXP2000s assert byte lanes for PCI I/O * transactions the other way round (MEM transactions don't have this - * issue), so we need to override the standard functions. B0 and later - * have a bit that can be set to 1 to get the 'proper' behavior, but - * since that isn't available on the A? revisions we just keep doing - * things manually. + * issue), so if we want to support those models, we need to override + * the standard I/O functions. + * + * B0 and later have a bit that can be set to 1 to get the proper + * behavior for I/O transactions, which then allows us to use the + * standard I/O functions. This is what we do if the user does not + * explicitly ask for support for pre-B0. */ +#ifdef CONFIG_IXP2000_SUPPORT_BROKEN_PCI_IO +#define ___io(p) ((void __iomem *)((p)+IXP2000_PCI_IO_VIRT_BASE)) + #define alignb(addr) (void __iomem *)((unsigned long)(addr) ^ 3) #define alignw(addr) (void __iomem *)((unsigned long)(addr) ^ 2) @@ -119,6 +124,9 @@ #define ioport_map(port, nr) ___io(port) #define ioport_unmap(addr) +#else +#define __io(p) ((void __iomem *)((p)+IXP2000_PCI_IO_VIRT_BASE)) +#endif #ifdef CONFIG_ARCH_IXDP2X01 -- cgit v1.2.3