gpu: nvgpu: add user API to get read-only syncpoint address map

Add User space API NVGPU_AS_IOCTL_GET_SYNC_RO_MAP to get read-only syncpoint
address map in user space

We already map whole syncpoint shim to each address space with base address
being vm->syncpt_ro_map_gpu_va

This new API exposes this base GPU_VA address of syncpoint map, and unit size
of each syncpoint to user space.
User space can then calculate address of each syncpoint as
syncpoint_address = base_gpu_va + (syncpoint_id * syncpoint_unit_size)

Note that this syncpoint address is read_only, and should be only used for
inserting semaphore acquires.
Adding semaphore release with this address would result in MMU_FAULT

Define new HAL g->ops.fifo.get_sync_ro_map and set this for all GPUs supported
on Xavier SoC

Bug 200327559

Change-Id: Ica0db48fc28fdd0ff2a5eb09574dac843dc5e4fd
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1649365
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/common/mm/vm.c b/drivers/gpu/nvgpu/common/mm/vm.c
index f2d04dab..e5ad22f3 100644
--- a/drivers/gpu/nvgpu/common/mm/vm.c
+++ b/drivers/gpu/nvgpu/common/mm/vm.c
@@ -459,6 +459,7 @@ int __nvgpu_vm_init(struct mm_gk20a *mm,
 
         vm->mapped_buffers = NULL;
 
+        nvgpu_mutex_init(&vm->syncpt_ro_map_lock);
         nvgpu_mutex_init(&vm->update_gmmu_lock);
         nvgpu_ref_init(&vm->ref);
         nvgpu_init_list_node(&vm->vm_area_list);
@@ -614,6 +615,7 @@ static void __nvgpu_vm_remove(struct vm_gk20a *vm)
 
         nvgpu_mutex_release(&vm->update_gmmu_lock);
 
+        nvgpu_mutex_destroy(&vm->syncpt_ro_map_lock);
         nvgpu_kfree(g, vm);
 }