From: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com
[ Upstream commit 2ae86955703e9e6a119af4bbe27f6b6dd7a43131 ]
The TTSEL bit of IMUCTRn register of R-Car Gen3 needs to be set unused MMU context number even if uTLBs are disabled (The MMUEN bit of IMUCTRn register = 0). Since initial values of IMUCTRn.TTSEL on all IPMMU-domains are 0, this patch adds a new feature "reserved_context" to reserve IPMMU context number 0 as the unused MMU context.
Signed-off-by: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/iommu/ipmmu-vmsa.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c index 40ae6e87cb88..559ecdf84729 100644 --- a/drivers/iommu/ipmmu-vmsa.c +++ b/drivers/iommu/ipmmu-vmsa.c @@ -47,6 +47,7 @@ struct ipmmu_features { unsigned int number_of_contexts; bool setup_imbuscr; bool twobit_imttbcr_sl0; + bool reserved_context; };
struct ipmmu_vmsa_device { @@ -917,6 +918,7 @@ static const struct ipmmu_features ipmmu_features_default = { .number_of_contexts = 1, /* software only tested with one context */ .setup_imbuscr = true, .twobit_imttbcr_sl0 = false, + .reserved_context = false, };
static const struct ipmmu_features ipmmu_features_r8a7795 = { @@ -925,6 +927,7 @@ static const struct ipmmu_features ipmmu_features_r8a7795 = { .number_of_contexts = 8, .setup_imbuscr = false, .twobit_imttbcr_sl0 = true, + .reserved_context = true, };
static const struct of_device_id ipmmu_of_ids[] = { @@ -1018,6 +1021,11 @@ static int ipmmu_probe(struct platform_device *pdev) }
ipmmu_device_reset(mmu); + + if (mmu->features->reserved_context) { + dev_info(&pdev->dev, "IPMMU context 0 is reserved\n"); + set_bit(0, mmu->ctx); + } }
/*