diff options
author | Joerg Roedel <joerg.roedel@amd.com> | 2009-08-26 15:26:30 +0200 |
---|---|---|
committer | Joerg Roedel <joerg.roedel@amd.com> | 2009-09-03 16:15:42 +0200 |
commit | 0feae533ddebe02cda6ccce5cac7349b446776a8 (patch) | |
tree | d9c82d7ebec45d96194aeaf27acfbbd2015545ac /arch/x86/kernel | |
parent | 2650815fb03fe2bf1e6701584087ba669dcf92cd (diff) |
x86/amd-iommu: Add passthrough mode initialization functions
When iommu=pt is passed on kernel command line the devices
should run untranslated. This requires the allocation of a
special domain for that purpose. This patch implements the
allocation and initialization path for iommu=pt.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/amd_iommu.c | 72 |
1 files changed, 64 insertions, 8 deletions
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 0934348abfa..7987f20499a 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -41,6 +41,12 @@ static DEFINE_RWLOCK(amd_iommu_devtable_lock); static LIST_HEAD(iommu_pd_list); static DEFINE_SPINLOCK(iommu_pd_list_lock); +/* + * Domain for untranslated devices - only allocated + * if iommu=pt passed on kernel cmd line. + */ +static struct protection_domain *pt_domain; + #ifdef CONFIG_IOMMU_API static struct iommu_ops amd_iommu_ops; #endif @@ -1067,9 +1073,9 @@ static struct protection_domain *domain_for_device(u16 devid) * If a device is not yet associated with a domain, this function does * assigns it visible for the hardware */ -static void attach_device(struct amd_iommu *iommu, - struct protection_domain *domain, - u16 devid) +static void __attach_device(struct amd_iommu *iommu, + struct protection_domain *domain, + u16 devid) { unsigned long flags; u64 pte_root = virt_to_phys(domain->pt_root); @@ -1087,12 +1093,19 @@ static void attach_device(struct amd_iommu *iommu, amd_iommu_pd_table[devid] = domain; write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); +} - /* - * We might boot into a crash-kernel here. The crashed kernel - * left the caches in the IOMMU dirty. So we have to flush - * here to evict all dirty stuff. - */ +static void attach_device(struct amd_iommu *iommu, + struct protection_domain *domain, + u16 devid) +{ + __attach_device(iommu, domain, devid); + + /* + * We might boot into a crash-kernel here. The crashed kernel + * left the caches in the IOMMU dirty. So we have to flush + * here to evict all dirty stuff. + */ iommu_queue_inv_dev_entry(iommu, devid); iommu_flush_tlb_pde(iommu, domain->id); } @@ -2219,3 +2232,46 @@ static struct iommu_ops amd_iommu_ops = { .domain_has_cap = amd_iommu_domain_has_cap, }; +/***************************************************************************** + * + * The next functions do a basic initialization of IOMMU for pass through + * mode + * + * In passthrough mode the IOMMU is initialized and enabled but not used for + * DMA-API translation. + * + *****************************************************************************/ + +int __init amd_iommu_init_passthrough(void) +{ + struct pci_dev *dev = NULL; + u16 devid, devid2; + + /* allocate passthroug domain */ + pt_domain = protection_domain_alloc(); + if (!pt_domain) + return -ENOMEM; + + pt_domain->mode |= PAGE_MODE_NONE; + + while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { + struct amd_iommu *iommu; + + devid = calc_devid(dev->bus->number, dev->devfn); + if (devid > amd_iommu_last_bdf) + continue; + + devid2 = amd_iommu_alias_table[devid]; + + iommu = amd_iommu_rlookup_table[devid2]; + if (!iommu) + continue; + + __attach_device(iommu, pt_domain, devid); + __attach_device(iommu, pt_domain, devid2); + } + + pr_info("AMD-Vi: Initialized for Passthrough Mode\n"); + + return 0; +} |