[RFC PATCH v4 3/8] iommu/arm-smmu-v3: support ops registration for CDX bus

From: Nipun Gupta
Date: Fri Oct 14 2022 - 00:42:26 EST


With new CDX bus supported for AMD FPGA devices on ARM
platform, the bus requires registration for the SMMU v3
driver.

Signed-off-by: Nipun Gupta <nipun.gupta@xxxxxxx>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index d32b02336411..8ec9f2baf12d 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -29,6 +29,7 @@
#include <linux/platform_device.h>

#include <linux/amba/bus.h>
+#include <linux/cdx/cdx_bus.h>

#include "arm-smmu-v3.h"
#include "../../iommu-sva-lib.h"
@@ -3690,16 +3691,27 @@ static int arm_smmu_set_bus_ops(struct iommu_ops *ops)
if (err)
goto err_reset_pci_ops;
}
+#endif
+#ifdef CONFIG_CDX_BUS
+ if (cdx_bus_type.iommu_ops != ops) {
+ err = bus_set_iommu(&cdx_bus_type, ops);
+ if (err)
+ goto err_reset_amba_ops;
+ }
#endif
if (platform_bus_type.iommu_ops != ops) {
err = bus_set_iommu(&platform_bus_type, ops);
if (err)
- goto err_reset_amba_ops;
+ goto err_reset_cdx_ops;
}

return 0;

-err_reset_amba_ops:
+err_reset_cdx_ops:
+#ifdef CONFIG_CDX_BUS
+ bus_set_iommu(&cdx_bus_type, NULL);
+#endif
+err_reset_amba_ops: __maybe_unused;
#ifdef CONFIG_ARM_AMBA
bus_set_iommu(&amba_bustype, NULL);
#endif
--
2.25.1