Merge "iommu: msm: Workaround MMU500 active pre-fetch BUG" (ee404009) · Commits · e / devices / android_kernel_sony_msm8994

drivers/iommu/Kconfig

+19 −0

Original line number	Diff line number	Diff line
		@@ -150,6 +150,25 @@ config MSM_IOMMU_TLBINVAL_ON_MAP

		If unsure, say Y here.

		config MMU500_ACTIVE_PREFETCH_BUG_WITH_SECTION_MAPPING
		bool "Don't align Virtual address at 1MB boundary"
		depends on MSM_IOMMU
		help
		Say Y here if the MMU500 revision has a bug in active prefetch
		which can cause TLB corruptions due to 1MB alignment of a buffer.
		Here is the sequence which will surface this BUG.
		1) Create a 2-level mapping in v7S format for 1MB buffer. Start of
		the buffer should be at even MB boundary.
		2) Create a section mapping for 1MB buffer adjacent to previous
		mapping in step 1.
		3) Access last page from 2 level mapping followed by an access into
		section mapped area.
		4) Step 3 will result into TLB corruption and this corruption can
		lead to any misbehavior (like Permission fault) for sub-sequent
		transactions.

		If unsure, say Y here if IOMMU mapping will not exhaust the VA space.

		# AMD IOMMU support
		config AMD_IOMMU
		bool "AMD IOMMU support"

+20 −2

Original line number	Diff line number	Diff line
		/* Copyright (c) 2010-2014, The Linux Foundation. All rights reserved.
		/* Copyright (c) 2010-2015, The Linux Foundation. All rights reserved.
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License version 2 and
		@@ -387,6 +387,21 @@ static struct msm_iova_data *msm_domain_to_iova_data(struct iommu_domain
		return iova_data;
		}

		#ifdef CONFIG_MMU500_ACTIVE_PREFETCH_BUG_WITH_SECTION_MAPPING
		static unsigned long get_alignment_order(unsigned long align)
		{
		if (align >= SZ_1M && align < SZ_2M)
		return ilog2(SZ_2M);
		else
		return ilog2(align);
		}
		#else
		static unsigned long get_alignment_order(unsigned long align)
		{
		return ilog2(align);
		}
		#endif

		int msm_allocate_iova_address(unsigned int iommu_domain,
		unsigned int partition_no,
		unsigned long size,
		@@ -396,6 +411,7 @@ int msm_allocate_iova_address(unsigned int iommu_domain,
		struct msm_iova_data *data;
		struct mem_pool *pool;
		unsigned long va;
		unsigned long aligned_order;

		data = find_domain(iommu_domain);

		@@ -410,8 +426,10 @@ int msm_allocate_iova_address(unsigned int iommu_domain,
		if (!pool->gpool)
		return -EINVAL;

		aligned_order = get_alignment_order(align);

		mutex_lock(&pool->pool_mutex);
		va = gen_pool_alloc_aligned(pool->gpool, size, ilog2(align));
		va = gen_pool_alloc_aligned(pool->gpool, size, aligned_order);
		mutex_unlock(&pool->pool_mutex);
		if (va) {
		pool->free -= size;