habanalabs: add virtual memory and MMU modules

This patch adds the Virtual Memory and MMU modules.

Goya has an internal MMU which provides process isolation on the internal
DDR. The internal MMU also performs translations for transactions that go
from Goya to the Host.

The driver is responsible for allocating and freeing memory on the DDR
upon user request. It also provides an interface to map and unmap DDR and
Host memory to the device address space.

The MMU in Goya supports 3-level and 4-level page tables. With 3-level, the
size of each page is 2MB, while with 4-level the size of each page is 4KB.

In the DDR, the physical pages are always 2MB.

Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Omer Shpigelman <oshpigelman@habana.ai>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 18 insertions, 1 deletions

diff --git a/drivers/misc/habanalabs/context.c b/drivers/misc/habanalabs/context.c
index c3854714b46c..619ace1c4ef7 100644
--- a/drivers/misc/habanalabs/context.c
+++ b/drivers/misc/habanalabs/context.c
@@ -25,8 +25,10 @@ static void hl_ctx_fini(struct hl_ctx *ctx)
 	for (i = 0 ; i < HL_MAX_PENDING_CS ; i++)
 		dma_fence_put(ctx->cs_pending[i]);
 
-	if (ctx->asid != HL_KERNEL_ASID_ID)
+	if (ctx->asid != HL_KERNEL_ASID_ID) {
+		hl_vm_ctx_fini(ctx);
 		hl_asid_free(hdev, ctx->asid);
+	}
 }
 
 void hl_ctx_do_release(struct kref *ref)
@@ -96,6 +98,8 @@ void hl_ctx_free(struct hl_device *hdev, struct hl_ctx *ctx)
 
 int hl_ctx_init(struct hl_device *hdev, struct hl_ctx *ctx, bool is_kernel_ctx)
 {
+	int rc = 0;
+
 	ctx->hdev = hdev;
 
 	kref_init(&ctx->refcount);
@@ -113,9 +117,22 @@ int hl_ctx_init(struct hl_device *hdev, struct hl_ctx *ctx, bool is_kernel_ctx)
 			dev_err(hdev->dev, "No free ASID, failed to create context\n");
 			return -ENOMEM;
 		}
+
+		rc = hl_vm_ctx_init(ctx);
+		if (rc) {
+			dev_err(hdev->dev, "Failed to init mem ctx module\n");
+			rc = -ENOMEM;
+			goto mem_ctx_err;
+		}
 	}
 
 	return 0;
+
+mem_ctx_err:
+	if (ctx->asid != HL_KERNEL_ASID_ID)
+		hl_asid_free(hdev, ctx->asid);
+
+	return rc;
 }
 
 void hl_ctx_get(struct hl_device *hdev, struct hl_ctx *ctx)