blob: 6053223c5f48dbad62963d25e70f3e864075c264 [file] [log] [blame]
From b8e3921f5975f97e61777aeda2ca1b1d320a93a7 Mon Sep 17 00:00:00 2001
From: Robin Murphy <>
Date: Mon, 30 Sep 2019 15:11:01 +0100
Subject: [PATCH] iommu/io-pgtable-arm: Support all Mali configurations
commit 1be08f458d1602275b02f5357ef069957058f3fd upstream.
In principle, Midgard GPUs supporting smaller VA sizes should only
require 3-level pagetables, since level 0 only resolves bits 48:40 of
the address. However, the kbase driver does not appear to have any
notion of a variable start level, and empirically T720 and T820 rapidly
blow up with translation faults unless given a full 4-level table,
despite only supporting a 33-bit VA size.
The 'real' IAS value is still valuable in terms of validating addresses
on map/unmap, so tweak the allocator to allow smaller values while still
forcing the resultant tables to the full 4 levels. As far as I can test,
this should make all known Midgard variants happy.
Fixes: d08d42de6432 ("iommu: io-pgtable: Add ARM Mali midgard MMU page table format")
Tested-by: Neil Armstrong <>
Reviewed-by: Steven Price <>
Reviewed-by: Rob Herring <>
Signed-off-by: Robin Murphy <>
Signed-off-by: Will Deacon <>
Signed-off-by: Paul Gortmaker <>
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 3310d9d9cb2e..1446c800a1dd 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -1012,7 +1012,7 @@ arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
if (cfg->quirks)
return NULL;
- if (cfg->ias != 48 || cfg->oas > 40)
+ if (cfg->ias > 48 || cfg->oas > 40)
return NULL;
cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
@@ -1021,6 +1021,11 @@ arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
if (!data)
return NULL;
+ /* Mali seems to need a full 4-level table regardless of IAS */
+ if (data->levels < ARM_LPAE_MAX_LEVELS) {
+ data->levels = ARM_LPAE_MAX_LEVELS;
+ data->pgd_size = sizeof(arm_lpae_iopte);
+ }
* MEMATTR: Mali has no actual notion of a non-cacheable type, so the
* best we can do is mimic the out-of-tree driver and hope that the