[PATCH v4 5/9] iommu/arm-smmu: Attach to host1x context device bus

From: cyndis
Date: Tue Mar 01 2022 - 11:15:56 EST


From: Mikko Perttunen <mperttunen@xxxxxxxxxx>

Set itself as the IOMMU for the host1x context device bus, containing
"dummy" devices used for Host1x context isolation.

Signed-off-by: Mikko Perttunen <mperttunen@xxxxxxxxxx>
---
drivers/iommu/arm/arm-smmu/arm-smmu.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 4bc75c4ce402..23082675d542 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -39,6 +39,7 @@

#include <linux/amba/bus.h>
#include <linux/fsl/mc.h>
+#include <linux/host1x_context_bus.h>

#include "arm-smmu.h"

@@ -2051,8 +2052,20 @@ static int arm_smmu_bus_init(struct iommu_ops *ops)
goto err_reset_pci_ops;
}
#endif
+#ifdef CONFIG_TEGRA_HOST1X_CONTEXT_BUS
+ if (!iommu_present(&host1x_context_device_bus_type)) {
+ err = bus_set_iommu(&host1x_context_device_bus_type, ops);
+ if (err)
+ goto err_reset_fsl_mc_ops;
+ }
+#endif
+
return 0;

+err_reset_fsl_mc_ops: __maybe_unused;
+#ifdef CONFIG_FSL_MC_BUS
+ bus_set_iommu(&fsl_mc_bus_type, NULL);
+#endif
err_reset_pci_ops: __maybe_unused;
#ifdef CONFIG_PCI
bus_set_iommu(&pci_bus_type, NULL);
--
2.35.0