[V2,1/7] iommu/vt-d: Support size of the register set in DRHD
Commit Message
From: Kan Liang <kan.liang@linux.intel.com>
A new field, which indicates the size of the remapping hardware register
set for this remapping unit, is introduced in the DMA-remapping hardware
unit definition (DRHD) structure with the VT-d Spec 4.0.
With the information, SW doesn't need to 'guess' the size of the
register set anymore.
Update the struct acpi_dmar_hardware_unit to reflect the field.
Store the size of the register set in struct dmar_drhd_unit for each
dmar device.
The 'size' information is ResvZ for the old BIOS and platforms. Fall
back to the old guessing method. There is nothing changed.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
---
drivers/iommu/intel/dmar.c | 11 +++++++----
include/acpi/actbl1.h | 2 +-
include/linux/dmar.h | 1 +
3 files changed, 9 insertions(+), 5 deletions(-)
@@ -427,6 +427,8 @@ static int dmar_parse_one_drhd(struct acpi_dmar_header *header, void *arg)
memcpy(dmaru->hdr, header, header->length);
dmaru->reg_base_addr = drhd->address;
dmaru->segment = drhd->segment;
+ /* The size of the register set is 2 ^ N 4 KB pages. */
+ dmaru->reg_size = 1UL << (drhd->size + 12);
dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
dmaru->devices = dmar_alloc_dev_scope((void *)(drhd + 1),
((void *)drhd) + drhd->header.length,
@@ -956,17 +958,18 @@ static void unmap_iommu(struct intel_iommu *iommu)
/**
* map_iommu: map the iommu's registers
* @iommu: the iommu to map
- * @phys_addr: the physical address of the base resgister
+ * @drhd: DMA remapping hardware definition structure
*
* Memory map the iommu's registers. Start w/ a single page, and
* possibly expand if that turns out to be insufficent.
*/
-static int map_iommu(struct intel_iommu *iommu, u64 phys_addr)
+static int map_iommu(struct intel_iommu *iommu, struct dmar_drhd_unit *drhd)
{
+ u64 phys_addr = drhd->reg_base_addr;
int map_size, err=0;
iommu->reg_phys = phys_addr;
- iommu->reg_size = VTD_PAGE_SIZE;
+ iommu->reg_size = drhd->reg_size;
if (!request_mem_region(iommu->reg_phys, iommu->reg_size, iommu->name)) {
pr_err("Can't reserve memory\n");
@@ -1050,7 +1053,7 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd)
}
sprintf(iommu->name, "dmar%d", iommu->seq_id);
- err = map_iommu(iommu, drhd->reg_base_addr);
+ err = map_iommu(iommu, drhd);
if (err) {
pr_err("Failed to map %s\n", iommu->name);
goto error_free_seq_id;
@@ -802,7 +802,7 @@ struct acpi_dmar_pci_path {
struct acpi_dmar_hardware_unit {
struct acpi_dmar_header header;
u8 flags;
- u8 reserved;
+ u8 size; /* Size of the register set */
u16 segment;
u64 address; /* Register Base Address */
};
@@ -39,6 +39,7 @@ struct dmar_drhd_unit {
struct list_head list; /* list of drhd units */
struct acpi_dmar_header *hdr; /* ACPI header */
u64 reg_base_addr; /* register base address*/
+ unsigned long reg_size; /* size of register set */
struct dmar_dev_scope *devices;/* target device array */
int devices_cnt; /* target device count */
u16 segment; /* PCI domain */