accel/ivpu: Do not use SSID 1

The SSID=1 is used by the firmware as default value in
case SSID mapping is not initialized. This allows
detecting use of miss-configured memory contexts.
The future FW versions may not allow using SSID=1.

SSID=65 is valid value, number of contexts are limited
by number of available command queues, but SSID can be
any u16 value.

Fixes: 35b13763 ("accel/ivpu: Introduce a new DRM driver for Intel VPU")
Co-developed-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>
Signed-off-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>
Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230323125504.2586442-4-stanislaw.gruszka@linux.intel.com

drivers/accel/ivpu/ivpu_drv.c

@@ -474,8 +474,8 @@ static int ivpu_dev_init(struct ivpu_device *vdev)
 
 	vdev->hw->ops = &ivpu_hw_mtl_ops;
 	vdev->platform = IVPU_PLATFORM_INVALID;
-	vdev->context_xa_limit.min = IVPU_GLOBAL_CONTEXT_MMU_SSID + 1;
-	vdev->context_xa_limit.max = IVPU_CONTEXT_LIMIT;
+	vdev->context_xa_limit.min = IVPU_USER_CONTEXT_MIN_SSID;
+	vdev->context_xa_limit.max = IVPU_USER_CONTEXT_MAX_SSID;
 	atomic64_set(&vdev->unique_id_counter, 0);
 	xa_init_flags(&vdev->context_xa, XA_FLAGS_ALLOC);
 	xa_init_flags(&vdev->submitted_jobs_xa, XA_FLAGS_ALLOC1);

drivers/accel/ivpu/ivpu_drv.h

@@ -25,7 +25,10 @@
 #define PCI_DEVICE_ID_MTL   0x7d1d
 
 #define IVPU_GLOBAL_CONTEXT_MMU_SSID 0
-#define IVPU_CONTEXT_LIMIT	     64
+/* SSID 1 is used by the VPU to represent invalid context */
+#define IVPU_USER_CONTEXT_MIN_SSID   2
+#define IVPU_USER_CONTEXT_MAX_SSID   (IVPU_USER_CONTEXT_MIN_SSID + 63)
+
 #define IVPU_NUM_ENGINES	     2
 
 #define IVPU_PLATFORM_SILICON 0