Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4158c2ec authored by Joerg Roedel's avatar Joerg Roedel
Browse files

iommu/vt-d: Detect pre enabled translation 



Add code to detect whether translation is already enabled in
the IOMMU. Save this state in a flags field added to
struct intel_iommu.

Tested-by: default avatarZhenHua Li <zhen-hual@hp.com>
Tested-by: default avatarBaoquan He <bhe@redhat.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 5f0a7f76

drivers/iommu/intel-iommu.c

+19 −0
Original line number Diff line number Diff line
@@ -443,6 +443,20 @@ static LIST_HEAD(device_domain_list); 


static const struct iommu_ops intel_iommu_ops;



static bool translation_pre_enabled(struct intel_iommu *iommu)

{

	return (iommu->flags & VTD_FLAG_TRANS_PRE_ENABLED);

}



static void init_translation_status(struct intel_iommu *iommu)

{

	u32 gsts;



	gsts = readl(iommu->reg + DMAR_GSTS_REG);

	if (gsts & DMA_GSTS_TES)

		iommu->flags |= VTD_FLAG_TRANS_PRE_ENABLED;

}



/* Convert generic 'struct iommu_domain to private struct dmar_domain */

static struct dmar_domain *to_dmar_domain(struct iommu_domain *dom)

{
@@ -2809,6 +2823,11 @@ static int __init init_dmars(void) 
		if (ret)

			goto free_iommu;



		init_translation_status(iommu);



		if (translation_pre_enabled(iommu))

			pr_info("Translation already enabled - trying to copy translation structures\n");



		/*

		 * TBD:

		 * we could share the same root & context tables

include/linux/intel-iommu.h

+4 −0
Original line number Diff line number Diff line
@@ -320,6 +320,9 @@ enum { 
	MAX_SR_DMAR_REGS

};



#define VTD_FLAG_TRANS_PRE_ENABLED	(1 << 0)

#define VTD_FLAG_IRQ_REMAP_PRE_ENABLED	(1 << 1)



struct intel_iommu {

	void __iomem	*reg; /* Pointer to hardware regs, virtual addr */

	u64 		reg_phys; /* physical address of hw register set */
@@ -351,6 +354,7 @@ struct intel_iommu { 
#endif

	struct device	*iommu_dev; /* IOMMU-sysfs device */

	int		node;

	u32		flags;      /* Software defined flags */

};



static inline void __iommu_flush_cache(