Commit 86666c54 authored by Lucas Stach's avatar Lucas Stach
Browse files

drm/etnaviv: iommuv1: remove map_lock 



It wasn't protecting anything, as the single word writes used to
set up or tear down a translation are already inherently atomic,
so the spinlock is pure overhead.

Signed-off-by: default avatarLucas Stach <l.stach@pengutronix.de>
Reviewed-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
Reviewed-By: default avatarWladimir J. van der Laan <laanwj@gmail.com>
parent bd2442bc

drivers/gpu/drm/etnaviv/etnaviv_iommu.c

+0 −7
Original line number Diff line number Diff line
@@ -42,7 +42,6 @@ struct etnaviv_iommu_domain { 
	void *bad_page_cpu;

	dma_addr_t bad_page_dma;

	struct etnaviv_iommu_domain_pgtable pgtable;

	spinlock_t map_lock;

};



static struct etnaviv_iommu_domain *to_etnaviv_domain(struct iommu_domain *domain)
@@ -81,8 +80,6 @@ static int __etnaviv_iommu_init(struct etnaviv_iommu_domain *etnaviv_domain) 
		etnaviv_domain->pgtable.pgtable[i] =

			etnaviv_domain->bad_page_dma;



	spin_lock_init(&etnaviv_domain->map_lock);



	return 0;

}
@@ -110,9 +107,7 @@ static int etnaviv_iommuv1_map(struct iommu_domain *domain, unsigned long iova, 
	if (size != SZ_4K)

		return -EINVAL;



	spin_lock(&etnaviv_domain->map_lock);

	etnaviv_domain->pgtable.pgtable[index] = paddr;

	spin_unlock(&etnaviv_domain->map_lock);



	return 0;

}
@@ -126,9 +121,7 @@ static size_t etnaviv_iommuv1_unmap(struct iommu_domain *domain, 
	if (size != SZ_4K)

		return -EINVAL;



	spin_lock(&etnaviv_domain->map_lock);

	etnaviv_domain->pgtable.pgtable[index] = etnaviv_domain->bad_page_dma;

	spin_unlock(&etnaviv_domain->map_lock);



	return SZ_4K;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE