Commit ae180ba4 authored by Suravee Suthikulpanit's avatar Suravee Suthikulpanit Committed by Joerg Roedel
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iommu/amd: Process all IVHDs before enabling IOMMU features 



The ACPI IVRS table can contain multiple IVHD blocks. Each block contains
information used to initialize each IOMMU instance.

Currently, init_iommu_all sequentially process IVHD block and initialize
IOMMU instance one-by-one. However, certain features require all IOMMUs
to be configured in the same way system-wide. In case certain IVHD blocks
contain inconsistent information (most likely FW bugs), the driver needs
to go through and try to revert settings on IOMMUs that have already been
configured.

A solution is to split IOMMU initialization into 3 phases:

Phase1 : Processes information of the IVRS table for all IOMMU instances.
This allow all IVHDs to be processed prior to enabling features.

Phase2 : Early feature support check on all IOMMUs (using information in
IVHD blocks.

Phase3 : Iterates through all IOMMU instances and enabling features.

Signed-off-by: default avatarSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20220713225651.20758-5-suravee.suthikulpanit@amd.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 9dd299d8

drivers/iommu/amd/init.c

+19 −6
Original line number Diff line number Diff line
@@ -1721,7 +1721,6 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h, 
				 struct acpi_table_header *ivrs_base)

{

	struct amd_iommu_pci_seg *pci_seg;

	int ret;



	pci_seg = get_pci_segment(h->pci_seg, ivrs_base);

	if (pci_seg == NULL)
@@ -1802,6 +1801,13 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h, 
	if (!iommu->mmio_base)

		return -ENOMEM;



	return init_iommu_from_acpi(iommu, h);

}



static int __init init_iommu_one_late(struct amd_iommu *iommu)

{

	int ret;



	if (alloc_cwwb_sem(iommu))

		return -ENOMEM;
@@ -1823,10 +1829,6 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h, 
	if (amd_iommu_pre_enabled)

		amd_iommu_pre_enabled = translation_pre_enabled(iommu);



	ret = init_iommu_from_acpi(iommu, h);

	if (ret)

		return ret;



	if (amd_iommu_irq_remap) {

		ret = amd_iommu_create_irq_domain(iommu);

		if (ret)
@@ -1837,7 +1839,7 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h, 
	 * Make sure IOMMU is not considered to translate itself. The IVRS

	 * table tells us so, but this is a lie!

	 */

	pci_seg->rlookup_table[iommu->devid] = NULL;

	iommu->pci_seg->rlookup_table[iommu->devid] = NULL;



	return 0;

}
@@ -1882,6 +1884,7 @@ static int __init init_iommu_all(struct acpi_table_header *table) 
	end += table->length;

	p += IVRS_HEADER_LENGTH;



	/* Phase 1: Process all IVHD blocks */

	while (p < end) {

		h = (struct ivhd_header *)p;

		if (*p == amd_iommu_target_ivhd_type) {
@@ -1907,6 +1910,16 @@ static int __init init_iommu_all(struct acpi_table_header *table) 
	}

	WARN_ON(p != end);



	/* Phase 2 : Early feature support check */

	get_global_efr();



	/* Phase 3 : Enabling IOMMU features */

	for_each_iommu(iommu) {

		ret = init_iommu_one_late(iommu);

		if (ret)

			return ret;

	}



	return 0;

}