From bff6547bb6a4e82c399d74e7fba78b12d2f162ed Mon Sep 17 00:00:00 2001 From: Muli Ben-Yehuda Date: Thu, 7 Dec 2006 02:14:07 +0100 Subject: [PATCH] [PATCH] Calgary: allow compiling Calgary in but not using it by default This patch makes it possible to compile Calgary in but not use it by default. In this mode, use 'iommu=calgary' to activate it. Signed-off-by: Muli Ben-Yehuda Signed-off-by: Jon Mason Signed-off-by: Andi Kleen --- Documentation/x86_64/boot-options.txt | 3 ++- arch/x86_64/Kconfig | 11 +++++++++++ arch/x86_64/kernel/pci-calgary.c | 9 +++++++++ arch/x86_64/kernel/pci-dma.c | 5 +++++ include/asm-x86_64/calgary.h | 2 ++ 5 files changed, 29 insertions(+), 1 deletion(-) diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt index ab9b1c046c..dbdcaf68e3 100644 --- a/Documentation/x86_64/boot-options.txt +++ b/Documentation/x86_64/boot-options.txt @@ -179,7 +179,7 @@ PCI IOMMU iommu=[size][,noagp][,off][,force][,noforce][,leak][,memaper[=order]][,merge] - [,forcesac][,fullflush][,nomerge][,noaperture] + [,forcesac][,fullflush][,nomerge][,noaperture][,calgary] size set size of iommu (in bytes) noagp don't initialize the AGP driver and use full aperture. off don't use the IOMMU @@ -200,6 +200,7 @@ IOMMU buffering. nodac Forbid DMA >4GB panic Always panic when IOMMU overflows + calgary Use the Calgary IOMMU if it is available swiotlb=pages[,force] diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig index 010d2265f1..5cb509dbff 100644 --- a/arch/x86_64/Kconfig +++ b/arch/x86_64/Kconfig @@ -455,6 +455,17 @@ config CALGARY_IOMMU Normally the kernel will make the right choice by itself. If unsure, say Y. +config CALGARY_IOMMU_ENABLED_BY_DEFAULT + bool "Should Calgary be enabled by default?" + default y + depends on CALGARY_IOMMU + help + Should Calgary be enabled by default? if you choose 'y', Calgary + will be used (if it exists). If you choose 'n', Calgary will not be + used even if it exists. If you choose 'n' and would like to use + Calgary anyway, pass 'iommu=calgary' on the kernel command line. + If unsure, say Y. + # need this always selected by IOMMU for the VIA workaround config SWIOTLB bool diff --git a/arch/x86_64/kernel/pci-calgary.c b/arch/x86_64/kernel/pci-calgary.c index 8a1e4f35bc..0ddf29dae7 100644 --- a/arch/x86_64/kernel/pci-calgary.c +++ b/arch/x86_64/kernel/pci-calgary.c @@ -43,6 +43,12 @@ #include #include +#ifdef CONFIG_CALGARY_IOMMU_ENABLED_BY_DEFAULT +int use_calgary __read_mostly = 1; +#else +int use_calgary __read_mostly = 0; +#endif /* CONFIG_CALGARY_DEFAULT_ENABLED */ + #define PCI_DEVICE_ID_IBM_CALGARY 0x02a1 #define PCI_VENDOR_DEVICE_ID_CALGARY \ (PCI_VENDOR_ID_IBM | PCI_DEVICE_ID_IBM_CALGARY << 16) @@ -1061,6 +1067,9 @@ void __init detect_calgary(void) if (swiotlb || no_iommu || iommu_detected) return; + if (!use_calgary) + return; + if (!early_pci_allowed()) return; diff --git a/arch/x86_64/kernel/pci-dma.c b/arch/x86_64/kernel/pci-dma.c index f8d857453f..683b7a5c1a 100644 --- a/arch/x86_64/kernel/pci-dma.c +++ b/arch/x86_64/kernel/pci-dma.c @@ -296,6 +296,11 @@ __init int iommu_setup(char *p) gart_parse_options(p); #endif +#ifdef CONFIG_CALGARY_IOMMU + if (!strncmp(p, "calgary", 7)) + use_calgary = 1; +#endif /* CONFIG_CALGARY_IOMMU */ + p += strcspn(p, ","); if (*p == ',') ++p; diff --git a/include/asm-x86_64/calgary.h b/include/asm-x86_64/calgary.h index 6b93f5a3a5..7ee9006457 100644 --- a/include/asm-x86_64/calgary.h +++ b/include/asm-x86_64/calgary.h @@ -51,6 +51,8 @@ struct iommu_table { #define TCE_TABLE_SIZE_4M 6 #define TCE_TABLE_SIZE_8M 7 +extern int use_calgary; + #ifdef CONFIG_CALGARY_IOMMU extern int calgary_iommu_init(void); extern void detect_calgary(void); -- 2.39.5