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, 32 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/ioctl_as.c b/drivers/gpu/nvgpu/common/linux/ioctl_as.c
index 8aea3d22..c5769476 100644
--- a/drivers/gpu/nvgpu/common/linux/ioctl_as.c
+++ b/drivers/gpu/nvgpu/common/linux/ioctl_as.c
@@ -1,7 +1,7 @@
 /*
  * GK20A Address Spaces
  *
- * Copyright (c) 2011-2017, NVIDIA CORPORATION.  All rights reserved.
+ * Copyright (c) 2011-2018, NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -256,6 +256,33 @@ static int gk20a_as_ioctl_get_va_regions(
         return 0;
 }
 
+static int nvgpu_as_ioctl_get_sync_ro_map(
+        struct gk20a_as_share *as_share,
+        struct nvgpu_as_get_sync_ro_map_args *args)
+{
+#ifdef CONFIG_TEGRA_GK20A_NVHOST
+        struct vm_gk20a *vm = as_share->vm;
+        struct gk20a *g = gk20a_from_vm(vm);
+        u64 base_gpuva;
+        u32 sync_size;
+        int err = 0;
+
+        if (!g->ops.fifo.get_sync_ro_map)
+                return -EINVAL;
+
+        err = g->ops.fifo.get_sync_ro_map(vm, &base_gpuva, &sync_size);
+        if (err)
+                return err;
+
+        args->base_gpuva = base_gpuva;
+        args->sync_size = sync_size;
+
+        return err;
+#else
+        return -EINVAL;
+#endif
+}
+
 int gk20a_as_dev_open(struct inode *inode, struct file *filp)
 {
         struct nvgpu_os_linux *l;
@@ -367,6 +394,10 @@ long gk20a_as_dev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                 err = gk20a_as_ioctl_map_buffer_batch(as_share,
                                 (struct nvgpu_as_map_buffer_batch_args *)buf);
                 break;
+        case NVGPU_AS_IOCTL_GET_SYNC_RO_MAP:
+                err = nvgpu_as_ioctl_get_sync_ro_map(as_share,
+                        (struct nvgpu_as_get_sync_ro_map_args *)buf);
+                break;
         default:
                 err = -ENOTTY;
                 break;