Commit 4db96bfe authored by Kan Liang's avatar Kan Liang Committed by Joerg Roedel
Browse files

iommu/vt-d: Support size of the register set in DRHD 



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 this
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: default avatarKan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20230128200428.1459118-2-kan.liang@linux.intel.com


Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent e06d2443

drivers/iommu/intel/dmar.c

+7 −4
Original line number Diff line number Diff line
@@ -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;

include/acpi/actbl1.h

+1 −1
Original line number Diff line number Diff line
@@ -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 */

};

include/linux/dmar.h

+1 −0
Original line number Diff line number Diff line
@@ -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		*/