From 2b324506341cb3baf65f3b6a0f950dd7648938ac Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 21 Jun 2012 16:29:10 +0200 Subject: [PATCH] iommu/amd: Add routines to manage irq remapping tables Add routines to: * Alloc remapping tables and single entries from these tables * Change entries in the tables * Free entries in the table Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu.c | 228 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 228 insertions(+) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index e27b354..4e429e7 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -31,6 +31,12 @@ #include #include #include +#include +#include +#include +#include +#include +#include #include #include #include @@ -3773,3 +3779,225 @@ int amd_iommu_device_info(struct pci_dev *pdev, return 0; } EXPORT_SYMBOL(amd_iommu_device_info); + +#ifdef CONFIG_IRQ_REMAP + +/***************************************************************************** + * + * Interrupt Remapping Implementation + * + *****************************************************************************/ + +union irte { + u32 val; + struct { + u32 valid : 1, + no_fault : 1, + int_type : 3, + rq_eoi : 1, + dm : 1, + rsvd_1 : 1, + destination : 8, + vector : 8, + rsvd_2 : 8; + } fields; +}; + +#define DTE_IRQ_PHYS_ADDR_MASK (((1ULL << 45)-1) << 6) +#define DTE_IRQ_REMAP_INTCTL (2ULL << 60) +#define DTE_IRQ_TABLE_LEN (8ULL << 1) +#define DTE_IRQ_REMAP_ENABLE 1ULL + +static void set_dte_irq_entry(u16 devid, struct irq_remap_table *table) +{ + u64 dte; + + dte = amd_iommu_dev_table[devid].data[2]; + dte &= ~DTE_IRQ_PHYS_ADDR_MASK; + dte |= virt_to_phys(table->table); + dte |= DTE_IRQ_REMAP_INTCTL; + dte |= DTE_IRQ_TABLE_LEN; + dte |= DTE_IRQ_REMAP_ENABLE; + + amd_iommu_dev_table[devid].data[2] = dte; +} + +#define IRTE_ALLOCATED (~1U) + +static struct irq_remap_table *get_irq_table(u16 devid, bool ioapic) +{ + struct irq_remap_table *table = NULL; + struct amd_iommu *iommu; + unsigned long flags; + u16 alias; + + write_lock_irqsave(&amd_iommu_devtable_lock, flags); + + iommu = amd_iommu_rlookup_table[devid]; + if (!iommu) + goto out_unlock; + + table = irq_lookup_table[devid]; + if (table) + goto out; + + alias = amd_iommu_alias_table[devid]; + table = irq_lookup_table[alias]; + if (table) { + irq_lookup_table[devid] = table; + set_dte_irq_entry(devid, table); + iommu_flush_dte(iommu, devid); + goto out; + } + + /* Nothing there yet, allocate new irq remapping table */ + table = kzalloc(sizeof(*table), GFP_ATOMIC); + if (!table) + goto out; + + if (ioapic) + /* Keep the first 32 indexes free for IOAPIC interrupts */ + table->min_index = 32; + + table->table = kmem_cache_alloc(amd_iommu_irq_cache, GFP_ATOMIC); + if (!table->table) { + kfree(table); + goto out; + } + + memset(table->table, 0, MAX_IRQS_PER_TABLE * sizeof(u32)); + + if (ioapic) { + int i; + + for (i = 0; i < 32; ++i) + table->table[i] = IRTE_ALLOCATED; + } + + irq_lookup_table[devid] = table; + set_dte_irq_entry(devid, table); + iommu_flush_dte(iommu, devid); + if (devid != alias) { + irq_lookup_table[alias] = table; + set_dte_irq_entry(devid, table); + iommu_flush_dte(iommu, alias); + } + +out: + iommu_completion_wait(iommu); + +out_unlock: + write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + + return table; +} + +static int alloc_irq_index(struct irq_cfg *cfg, u16 devid, int count) +{ + struct irq_remap_table *table; + unsigned long flags; + int index, c; + + table = get_irq_table(devid, false); + if (!table) + return -ENODEV; + + spin_lock_irqsave(&table->lock, flags); + + /* Scan table for free entries */ + for (c = 0, index = table->min_index; + index < MAX_IRQS_PER_TABLE; + ++index) { + if (table->table[index] == 0) + c += 1; + else + c = 0; + + if (c == count) { + struct irq_2_iommu *irte_info; + + for (; c != 0; --c) + table->table[index - c + 1] = IRTE_ALLOCATED; + + index -= count - 1; + + irte_info = &cfg->irq_2_iommu; + irte_info->sub_handle = devid; + irte_info->irte_index = index; + irte_info->iommu = (void *)cfg; + + goto out; + } + } + + index = -ENOSPC; + +out: + spin_unlock_irqrestore(&table->lock, flags); + + return index; +} + +static int get_irte(u16 devid, int index, union irte *irte) +{ + struct irq_remap_table *table; + unsigned long flags; + + table = get_irq_table(devid, false); + if (!table) + return -ENOMEM; + + spin_lock_irqsave(&table->lock, flags); + irte->val = table->table[index]; + spin_unlock_irqrestore(&table->lock, flags); + + return 0; +} + +static int modify_irte(u16 devid, int index, union irte irte) +{ + struct irq_remap_table *table; + struct amd_iommu *iommu; + unsigned long flags; + + iommu = amd_iommu_rlookup_table[devid]; + if (iommu == NULL) + return -EINVAL; + + table = get_irq_table(devid, false); + if (!table) + return -ENOMEM; + + spin_lock_irqsave(&table->lock, flags); + table->table[index] = irte.val; + spin_unlock_irqrestore(&table->lock, flags); + + iommu_flush_irt(iommu, devid); + iommu_completion_wait(iommu); + + return 0; +} + +static void free_irte(u16 devid, int index) +{ + struct irq_remap_table *table; + struct amd_iommu *iommu; + unsigned long flags; + + iommu = amd_iommu_rlookup_table[devid]; + if (iommu == NULL) + return; + + table = get_irq_table(devid, false); + if (!table) + return; + + spin_lock_irqsave(&table->lock, flags); + table->table[index] = 0; + spin_unlock_irqrestore(&table->lock, flags); + + iommu_flush_irt(iommu, devid); + iommu_completion_wait(iommu); +} + +#endif -- 2.7.4