Commit Graph

8 Commits

Author SHA1 Message Date
Robin Murphy 82db33dc5e iommu/io-pgtable-arm: Check for v7s-incapable systems
On machines with no 32-bit addressable RAM whatsoever, we shouldn't
even touch the v7s format as it's never going to work.

Fixes: e5fc9753b1 ("iommu/io-pgtable: Add ARMv7 short descriptor support")
Reported-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-16 09:34:23 +01:00
Robin Murphy e633fc7a13 iommu/io-pgtable-arm-v7s: Fix attributes when splitting blocks
Due to the attribute bits being all over the place in the different
types of short-descriptor PTEs, when remapping an existing entry, e.g.
splitting a section into pages, we take the approach of decomposing
the PTE attributes back to the IOMMU API flags to start from scratch.

On inspection, though, the existing code seems to have got the read-only
bit backwards and ignored the XN bit. How embarrassing...

Fortunately the primary user so far, the Mediatek IOMMU, both never
splits blocks (because it only serves non-overlapping DMA API calls) and
also ignores permissions anyway, but let's put things right before any
future users trip up.

Cc: <stable@vger.kernel.org>
Fixes: e5fc9753b1 ("iommu/io-pgtable: Add ARMv7 short descriptor support")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-19 09:40:16 +01:00
Robin Murphy e88ccab12a iommu/io-pgtable-arm-v7s: Support IOMMU_MMIO flag
Teach the short-descriptor format to create Device mappings when asked.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-04-07 15:07:50 +02:00
Yong Wu 1afe23194d iommu/io-pgtable: Add MTK 4GB mode in Short-descriptor
In MT8173, Normally the first 1GB PA is for the HW SRAM and Regs,
so the PA will be 33bits if the dram size is 4GB. We have a
"DRAM 4GB mode" toggle bit for this. If it's enabled, from CPU's
point of view, the dram PA will be from 0x1_00000000~0x1_ffffffff.

In short descriptor, the pagetable descriptor is always 32bit.
Mediatek extend bit9 in the lvl1 and lvl2 pgtable descriptor
as the 4GB mode.

In the 4GB mode, the bit9 must be set, then M4U help add 0x1_00000000
based on the PA in pagetable. Thus the M4U output address to EMI is
always 33bits(the input address is still 32bits).

We add a special quirk for this MTK-4GB mode. And in the standard
spec, Bit9 in the lvl1 is "IMPLEMENTATION DEFINED", while it's AP[2]
in the lvl2, therefore if this quirk is enabled, NO_PERMS is also
expected.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-04-05 15:39:37 +02:00
Robin Murphy 048b31ca97 iommu/io-pgtable-armv7s: Fix kmem_cache_alloc() flags
Whilst the default SLUB allocator happily just merges the original
allocation flags from kmem_cache_create() with those passed through
kmem_cache_alloc(), there is a code path in the SLAB allocator which
will aggressively BUG_ON() if the cache was created with SLAB_CACHE_DMA
but GFP_DMA is not specified for an allocation:

  kernel BUG at mm/slab.c:2536!
  Internal error: Oops - BUG: 0 [#1] SMP ARM
  Modules linked in:[    1.299311] Modules linked in:

  CPU: 1 PID: 1 Comm: swapper/0 Not tainted
  4.5.0-rc6-koelsch-05892-ge7e45ad53ab6795e #2270
  Hardware name: Generic R8A7791 (Flattened Device Tree)
  task: ef422040 ti: ef442000 task.ti: ef442000
  PC is at cache_alloc_refill+0x2a0/0x530
  LR is at _raw_spin_unlock+0x8/0xc
...
  [<c02c6928>] (cache_alloc_refill) from [<c02c6630>] (kmem_cache_alloc+0x7c/0xd4)
  [<c02c6630>] (kmem_cache_alloc) from [<c04444bc>]
  (__arm_v7s_alloc_table+0x5c/0x278)
  [<c04444bc>] (__arm_v7s_alloc_table) from [<c0444e1c>]
  (__arm_v7s_map.constprop.6+0x68/0x25c)
  [<c0444e1c>] (__arm_v7s_map.constprop.6) from [<c0445044>]
  (arm_v7s_map+0x34/0xa4)
  [<c0445044>] (arm_v7s_map) from [<c0c18ee4>] (arm_v7s_do_selftests+0x140/0x418)
  [<c0c18ee4>] (arm_v7s_do_selftests) from [<c0201760>]
  (do_one_initcall+0x100/0x1b4)
  [<c0201760>] (do_one_initcall) from [<c0c00d4c>]
  (kernel_init_freeable+0x120/0x1e8)
  [<c0c00d4c>] (kernel_init_freeable) from [<c067a364>] (kernel_init+0x8/0xec)
  [<c067a364>] (kernel_init) from [<c0206b68>] (ret_from_fork+0x14/0x2c)
  Code: 1a000003 e7f001f2 e3130001 0a000000 (e7f001f2)
  ---[ end trace 190f6f6b84352efd ]---

Keep the peace by adding GFP_DMA when allocating a table.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-03-02 14:48:50 +01:00
Robin Murphy 3850db49da iommu/io-pgtable: Rationalise quirk handling
As the number of io-pgtable implementations grows beyond 1, it's time
to rationalise the quirks mechanism before things have a chance to
start getting really ugly and out-of-hand.

To that end:
- Indicate exactly which quirks each format can/does support.
- Fail creating a table if a caller wants unsupported quirks.
- Properly document where each quirk applies and why.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-17 14:15:09 +00:00
Robin Murphy 507e4c9d19 iommu/io-pgtable: Add helper functions for TLB ops
Add some simple wrappers to avoid having the guts of the TLB operations
spilled all over the page table implementations, and to provide a point
to implement extra common functionality.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-17 14:15:08 +00:00
Robin Murphy e5fc9753b1 iommu/io-pgtable: Add ARMv7 short descriptor support
Add a nearly-complete ARMv7 short descriptor implementation, omitting
only a few legacy and CPU-centric aspects which shouldn't be necessary
for IOMMU API use anyway.

Reviewed-by: Yong Wu <yong.wu@mediatek.com>
Tested-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-17 14:14:57 +00:00