diff options
Diffstat (limited to 'drivers/iommu/amd_iommu_init.c')
| -rw-r--r-- | drivers/iommu/amd_iommu_init.c | 223 |
1 files changed, 199 insertions, 24 deletions
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index 2292a6cece76..382de42b8359 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -29,7 +29,6 @@ #include <linux/export.h> #include <linux/iommu.h> #include <linux/kmemleak.h> -#include <linux/crash_dump.h> #include <linux/mem_encrypt.h> #include <asm/pci-direct.h> #include <asm/iommu.h> @@ -39,6 +38,7 @@ #include <asm/io_apic.h> #include <asm/irq_remapping.h> +#include <linux/crash_dump.h> #include "amd_iommu_proto.h" #include "amd_iommu_types.h" #include "irq_remapping.h" @@ -197,6 +197,11 @@ spinlock_t amd_iommu_pd_lock; * page table root pointer. */ struct dev_table_entry *amd_iommu_dev_table; +/* + * Pointer to a device table which the content of old device table + * will be copied to. It's only be used in kdump kernel. + */ +static struct dev_table_entry *old_dev_tbl_cpy; /* * The alias table is a driver specific data structure which contains the @@ -210,6 +215,7 @@ u16 *amd_iommu_alias_table; * for a specific device. It is also indexed by the PCI device id. */ struct amd_iommu **amd_iommu_rlookup_table; +EXPORT_SYMBOL(amd_iommu_rlookup_table); /* * This table is used to find the irq remapping table for a given device id @@ -259,6 +265,28 @@ static int amd_iommu_enable_interrupts(void); static int __init iommu_go_to_state(enum iommu_init_state state); static void init_device_table_dma(void); +static bool amd_iommu_pre_enabled = true; + +bool translation_pre_enabled(struct amd_iommu *iommu) +{ + return (iommu->flags & AMD_IOMMU_FLAG_TRANS_PRE_ENABLED); +} +EXPORT_SYMBOL(translation_pre_enabled); + +static void clear_translation_pre_enabled(struct amd_iommu *iommu) +{ + iommu->flags &= ~AMD_IOMMU_FLAG_TRANS_PRE_ENABLED; +} + +static void init_translation_status(struct amd_iommu *iommu) +{ + u32 ctrl; + + ctrl = readl(iommu->mmio_base + MMIO_CONTROL_OFFSET); + if (ctrl & (1<<CONTROL_IOMMU_EN)) + iommu->flags |= AMD_IOMMU_FLAG_TRANS_PRE_ENABLED; +} + static inline void update_last_devid(u16 devid) { if (devid > amd_iommu_last_bdf) @@ -616,6 +644,14 @@ static void iommu_enable_command_buffer(struct amd_iommu *iommu) amd_iommu_reset_cmd_buffer(iommu); } +/* + * This function disables the command buffer + */ +static void iommu_disable_command_buffer(struct amd_iommu *iommu) +{ + iommu_feature_disable(iommu, CONTROL_CMDBUF_EN); +} + static void __init free_command_buffer(struct amd_iommu *iommu) { free_pages((unsigned long)iommu->cmd_buf, get_order(CMD_BUFFER_SIZE)); @@ -648,6 +684,14 @@ static void iommu_enable_event_buffer(struct amd_iommu *iommu) iommu_feature_enable(iommu, CONTROL_EVT_LOG_EN); } +/* + * This function disables the event log buffer + */ +static void iommu_disable_event_buffer(struct amd_iommu *iommu) +{ + iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN); +} + static void __init free_event_buffer(struct amd_iommu *iommu) { free_pages((unsigned long)iommu->evt_buf, get_order(EVT_BUFFER_SIZE)); @@ -809,6 +853,96 @@ static int get_dev_entry_bit(u16 devid, u8 bit) } +static bool copy_device_table(void) +{ + u64 int_ctl, int_tab_len, entry = 0, last_entry = 0; + struct dev_table_entry *old_devtb = NULL; + u32 lo, hi, devid, old_devtb_size; + phys_addr_t old_devtb_phys; + struct amd_iommu *iommu; + u16 dom_id, dte_v, irq_v; + gfp_t gfp_flag; + u64 tmp; + + if (!amd_iommu_pre_enabled) + return false; + + pr_warn("Translation is already enabled - trying to copy translation structures\n"); + for_each_iommu(iommu) { + /* All IOMMUs should use the same device table with the same size */ + lo = readl(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET); + hi = readl(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET + 4); + entry = (((u64) hi) << 32) + lo; + if (last_entry && last_entry != entry) { + pr_err("IOMMU:%d should use the same dev table as others!/n", + iommu->index); + return false; + } + last_entry = entry; + + old_devtb_size = ((entry & ~PAGE_MASK) + 1) << 12; + if (old_devtb_size != dev_table_size) { + pr_err("The device table size of IOMMU:%d is not expected!/n", + iommu->index); + return false; + } + } + + old_devtb_phys = entry & PAGE_MASK; + if (old_devtb_phys >= 0x100000000ULL) { + pr_err("The address of old device table is above 4G, not trustworthy!/n"); + return false; + } + old_devtb = memremap(old_devtb_phys, dev_table_size, MEMREMAP_WB); + if (!old_devtb) + return false; + + gfp_flag = GFP_KERNEL | __GFP_ZERO | GFP_DMA32; + old_dev_tbl_cpy = (void *)__get_free_pages(gfp_flag, + get_order(dev_table_size)); + if (old_dev_tbl_cpy == NULL) { + pr_err("Failed to allocate memory for copying old device table!/n"); + return false; + } + + for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) { + old_dev_tbl_cpy[devid] = old_devtb[devid]; + dom_id = old_devtb[devid].data[1] & DEV_DOMID_MASK; + dte_v = old_devtb[devid].data[0] & DTE_FLAG_V; + + if (dte_v && dom_id) { + old_dev_tbl_cpy[devid].data[0] = old_devtb[devid].data[0]; + old_dev_tbl_cpy[devid].data[1] = old_devtb[devid].data[1]; + __set_bit(dom_id, amd_iommu_pd_alloc_bitmap); + /* If gcr3 table existed, mask it out */ + if (old_devtb[devid].data[0] & DTE_FLAG_GV) { + tmp = DTE_GCR3_VAL_B(~0ULL) << DTE_GCR3_SHIFT_B; + tmp |= DTE_GCR3_VAL_C(~0ULL) << DTE_GCR3_SHIFT_C; + old_dev_tbl_cpy[devid].data[1] &= ~tmp; + tmp = DTE_GCR3_VAL_A(~0ULL) << DTE_GCR3_SHIFT_A; + tmp |= DTE_FLAG_GV; + old_dev_tbl_cpy[devid].data[0] &= ~tmp; + } + } + + irq_v = old_devtb[devid].data[2] & DTE_IRQ_REMAP_ENABLE; + int_ctl = old_devtb[devid].data[2] & DTE_IRQ_REMAP_INTCTL_MASK; + int_tab_len = old_devtb[devid].data[2] & DTE_IRQ_TABLE_LEN_MASK; + if (irq_v && (int_ctl || int_tab_len)) { + if ((int_ctl != DTE_IRQ_REMAP_INTCTL) || + (int_tab_len != DTE_IRQ_TABLE_LEN)) { + pr_err("Wrong old irq remapping flag: %#x\n", devid); + return false; + } + + old_dev_tbl_cpy[devid].data[2] = old_devtb[devid].data[2]; + } + } + memunmap(old_devtb); + + return true; +} + void amd_iommu_apply_erratum_63(u16 devid) { int sysmgt; @@ -1400,6 +1534,16 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h) iommu->int_enabled = false; + init_translation_status(iommu); + if (translation_pre_enabled(iommu) && !is_kdump_kernel()) { + iommu_disable(iommu); + clear_translation_pre_enabled(iommu); + pr_warn("Translation was enabled for IOMMU:%d but we are not in kdump mode\n", + iommu->index); + } + if (amd_iommu_pre_enabled) + amd_iommu_pre_enabled = translation_pre_enabled(iommu); + ret = init_iommu_from_acpi(iommu, h); if (ret) return ret; @@ -1893,8 +2037,7 @@ static int __init init_memory_definitions(struct acpi_table_header *table) } /* - * Init the device table to not allow DMA access for devices and - * suppress all page faults + * Init the device table to not allow DMA access for devices */ static void init_device_table_dma(void) { @@ -1903,14 +2046,6 @@ static void init_device_table_dma(void) for (devid = 0; devid <= amd_iommu_last_bdf; ++devid) { set_dev_entry_bit(devid, DEV_ENTRY_VALID); set_dev_entry_bit(devid, DEV_ENTRY_TRANSLATION); - /* - * In kdump kernels in-flight DMA from the old kernel might - * cause IO_PAGE_FAULTs. There are no reports that a kdump - * actually failed because of that, so just disable fault - * reporting in the hardware to get rid of the messages - */ - if (is_kdump_kernel()) - set_dev_entry_bit(devid, DEV_ENTRY_NO_PAGE_FAULT); } } @@ -2023,24 +2158,62 @@ static void iommu_enable_ga(struct amd_iommu *iommu) #endif } +static void early_enable_iommu(struct amd_iommu *iommu) +{ + iommu_disable(iommu); + iommu_init_flags(iommu); + iommu_set_device_table(iommu); + iommu_enable_command_buffer(iommu); + iommu_enable_event_buffer(iommu); + iommu_set_exclusion_range(iommu); + iommu_enable_ga(iommu); + iommu_enable(iommu); + iommu_flush_all_caches(iommu); +} + /* * This function finally enables all IOMMUs found in the system after - * they have been initialized + * they have been initialized. + * + * Or if in kdump kernel and IOMMUs are all pre-enabled, try to copy + * the old content of device table entries. Not this case or copy failed, + * just continue as normal kernel does. */ static void early_enable_iommus(void) { struct amd_iommu *iommu; - for_each_iommu(iommu) { - iommu_disable(iommu); - iommu_init_flags(iommu); - iommu_set_device_table(iommu); - iommu_enable_command_buffer(iommu); - iommu_enable_event_buffer(iommu); - iommu_set_exclusion_range(iommu); - iommu_enable_ga(iommu); - iommu_enable(iommu); - iommu_flush_all_caches(iommu); + + if (!copy_device_table()) { + /* + * If come here because of failure in copying device table from old + * kernel with all IOMMUs enabled, print error message and try to + * free allocated old_dev_tbl_cpy. + */ + if (amd_iommu_pre_enabled) + pr_err("Failed to copy DEV table from previous kernel.\n"); + if (old_dev_tbl_cpy != NULL) + free_pages((unsigned long)old_dev_tbl_cpy, + get_order(dev_table_size)); + + for_each_iommu(iommu) { + clear_translation_pre_enabled(iommu); + early_enable_iommu(iommu); + } + } else { + pr_info("Copied DEV table from previous kernel.\n"); + free_pages((unsigned long)amd_iommu_dev_table, + get_order(dev_table_size)); + amd_iommu_dev_table = old_dev_tbl_cpy; + for_each_iommu(iommu) { + iommu_disable_command_buffer(iommu); + iommu_disable_event_buffer(iommu); + iommu_enable_command_buffer(iommu); + iommu_enable_event_buffer(iommu); + iommu_enable_ga(iommu); + iommu_set_device_table(iommu); + iommu_flush_all_caches(iommu); + } } #ifdef CONFIG_IRQ_REMAP @@ -2276,7 +2449,8 @@ static int __init early_amd_iommu_init(void) /* Device table - directly used by all IOMMUs */ ret = -ENOMEM; - amd_iommu_dev_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, + amd_iommu_dev_table = (void *)__get_free_pages( + GFP_KERNEL | __GFP_ZERO | GFP_DMA32, get_order(dev_table_size)); if (amd_iommu_dev_table == NULL) goto out; @@ -2326,7 +2500,8 @@ static int __init early_amd_iommu_init(void) goto out; /* Disable any previously enabled IOMMUs */ - disable_iommus(); + if (!is_kdump_kernel() || amd_iommu_disabled) + disable_iommus(); if (amd_iommu_irq_remap) amd_iommu_irq_remap = check_ioapic_information(); |