diff options
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 1 | ||||
| -rw-r--r-- | Documentation/x86/x86_64/boot-options.txt | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/pci-dma.c | 21 | ||||
| -rw-r--r-- | drivers/net/ethernet/sfc/efx.c | 5 | ||||
| -rw-r--r-- | drivers/net/ethernet/sfc/falcon/efx.c | 5 |
5 files changed, 6 insertions, 30 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 11fc28ecdb6d..6d4a666748dd 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1705,7 +1705,6 @@ nopanic merge nomerge - forcesac soft pt [x86, IA-64] nobypass [PPC/POWERNV] diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt index 153b3a57fba2..341588ec4e29 100644 --- a/Documentation/x86/x86_64/boot-options.txt +++ b/Documentation/x86/x86_64/boot-options.txt @@ -208,7 +208,7 @@ IOMMU (input/output memory management unit) Kernel boot message: "PCI-DMA: Using Calgary IOMMU" iommu=[<size>][,noagp][,off][,force][,noforce][,leak[=<nr_of_leak_pages>] - [,memaper[=<order>]][,merge][,forcesac][,fullflush][,nomerge] + [,memaper[=<order>]][,merge][,fullflush][,nomerge] [,noaperture][,calgary] General iommu options: @@ -235,8 +235,6 @@ IOMMU (input/output memory management unit) (experimental). nomerge Don't do scatter-gather (SG) merging. noaperture Ask the IOMMU not to touch the aperture for AGP. - forcesac Force single-address cycle (SAC) mode for masks <40bits - (experimental). noagp Don't initialize the AGP driver and use full aperture. allowdac Allow double-address cycle (DAC) mode, i.e. DMA >4GB. DAC is used with 32-bit PCI to push a 64-bit address in diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index c7113fd18e32..b65b0d7072f1 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -20,8 +20,6 @@ static int forbid_dac __read_mostly; const struct dma_map_ops *dma_ops = &dma_direct_ops; EXPORT_SYMBOL(dma_ops); -static int iommu_sac_force __read_mostly; - #ifdef CONFIG_IOMMU_DEBUG int panic_on_overflow __read_mostly = 1; int force_iommu __read_mostly = 1; @@ -122,7 +120,7 @@ static __init int iommu_setup(char *p) if (!strncmp(p, "nomerge", 7)) iommu_merge = 0; if (!strncmp(p, "forcesac", 8)) - iommu_sac_force = 1; + pr_warn("forcesac option ignored.\n"); if (!strncmp(p, "allowdac", 8)) forbid_dac = 0; if (!strncmp(p, "nodac", 5)) @@ -162,23 +160,6 @@ int arch_dma_supported(struct device *dev, u64 mask) } #endif - /* Tell the device to use SAC when IOMMU force is on. This - allows the driver to use cheaper accesses in some cases. - - Problem with this is that if we overflow the IOMMU area and - return DAC as fallback address the device may not handle it - correctly. - - As a special case some controllers have a 39bit address - mode that is as efficient as 32bit (aic79xx). Don't force - SAC for these. Assume all masks <= 40 bits are of this - type. Normally this doesn't make any difference, but gives - more gentle handling of IOMMU overflow. */ - if (iommu_sac_force && (mask >= DMA_BIT_MASK(40))) { - dev_info(dev, "Force SAC with mask %Lx\n", mask); - return 0; - } - return 1; } EXPORT_SYMBOL(arch_dma_supported); diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index a4ebd8715494..661828e8fdcf 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -1289,9 +1289,8 @@ static int efx_init_io(struct efx_nic *efx) pci_set_master(pci_dev); - /* Set the PCI DMA mask. Try all possibilities from our - * genuine mask down to 32 bits, because some architectures - * (e.g. x86_64 with iommu_sac_force set) will allow 40 bit + /* Set the PCI DMA mask. Try all possibilities from our genuine mask + * down to 32 bits, because some architectures will allow 40 bit * masks event though they reject 46 bit masks. */ while (dma_mask > 0x7fffffffUL) { diff --git a/drivers/net/ethernet/sfc/falcon/efx.c b/drivers/net/ethernet/sfc/falcon/efx.c index 3d6c91e96589..dd5530a4f8c8 100644 --- a/drivers/net/ethernet/sfc/falcon/efx.c +++ b/drivers/net/ethernet/sfc/falcon/efx.c @@ -1242,9 +1242,8 @@ static int ef4_init_io(struct ef4_nic *efx) pci_set_master(pci_dev); - /* Set the PCI DMA mask. Try all possibilities from our - * genuine mask down to 32 bits, because some architectures - * (e.g. x86_64 with iommu_sac_force set) will allow 40 bit + /* Set the PCI DMA mask. Try all possibilities from our genuine mask + * down to 32 bits, because some architectures will allow 40 bit * masks event though they reject 46 bit masks. */ while (dma_mask > 0x7fffffffUL) { |