Subject: s/BROKEN_NS/BROKEN_SH/

Steve

On 08/09/2020 16:18, Neil Armstrong wrote:
The coherency integration of the IOMMU in the Mali-G52 found in the Amlogic 
G12B SoCs
is broken and leads to constant and random faults from the IOMMU.

Disabling shareability completely fixes the issue.

Signed-off-by: Neil Armstrong <narmstr...@baylibre.com>
---
  drivers/iommu/io-pgtable-arm.c | 7 ++++---
  include/linux/io-pgtable.h     | 4 ++++
  2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index dc7bcf858b6d..d2d48dc86556 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -440,7 +440,9 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct 
arm_lpae_io_pgtable *data,
                                << ARM_LPAE_PTE_ATTRINDX_SHIFT);
        }
- if (prot & IOMMU_CACHE)
+       if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_BROKEN_SH)
+               pte |= ARM_LPAE_PTE_SH_NS;
+       else if (prot & IOMMU_CACHE)
                pte |= ARM_LPAE_PTE_SH_IS;
        else
                pte |= ARM_LPAE_PTE_SH_OS;
@@ -1005,8 +1007,7 @@ arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, 
void *cookie)
  {
        struct arm_lpae_io_pgtable *data;
- /* No quirks for Mali (hopefully) */
-       if (cfg->quirks)
+       if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_BROKEN_SH))
                return NULL;
if (cfg->ias > 48 || cfg->oas > 40)
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index 23285ba645db..efb9c8f20909 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -86,6 +86,9 @@ struct io_pgtable_cfg {
         *
         * IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
         *      for use in the upper half of a split address space.
+        *
+        * IO_PGTABLE_QUIRK_ARM_BROKEN_SH: (ARM LPAE format) Disables 
shareability
+        *      when coherency integration is broken.
         */
        #define IO_PGTABLE_QUIRK_ARM_NS         BIT(0)
        #define IO_PGTABLE_QUIRK_NO_PERMS       BIT(1)
@@ -93,6 +96,7 @@ struct io_pgtable_cfg {
        #define IO_PGTABLE_QUIRK_ARM_MTK_EXT    BIT(3)
        #define IO_PGTABLE_QUIRK_NON_STRICT     BIT(4)
        #define IO_PGTABLE_QUIRK_ARM_TTBR1      BIT(5)
+       #define IO_PGTABLE_QUIRK_ARM_BROKEN_SH  BIT(6)
        unsigned long                   quirks;
        unsigned long                   pgsize_bitmap;
        unsigned int                    ias;


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