gpu: nvgpu: fix patch buf count update for vidmem

gr_gk20a_ctx_patch_write_begin() updates the patch buffer data_count
when the associated graphics context memory buffer has been
CPU-mapped; it was doing so by looking for a non-null cpu_va.

However, if the graphics context has been allocated from vidmem,
cpu_va is always 0, so we can't tell if nvgpu_mem_begin() was called
for the context buffer or not.

Instead:
- add a cpu_accessible flag to the nvgpu_mem struct and set
  it in nvgpu_mem_begin()

- return the value of that flag in nvgpu_mem_cpu_accessible()

- gr_gk20a_ctx_patch_write_begin() now calls this new function
  instead of checking cpu_va.

Bug 2012077
JIRA ESRM-74

Change-Id: I8401699f30b4ae7154111721c25c7ec3ff95d329
Signed-off-by: Peter Daifuku <pdaifuku@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1587293
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
index 2a20c2d9..06fb5497 100644
--- a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
@@ -682,7 +682,7 @@ int gr_gk20a_ctx_patch_write_begin(struct gk20a *g,
         if (err)
                 return err;
 
-        if (ch_ctx->gr_ctx->mem.cpu_va) {
+        if (nvgpu_mem_cpu_accessible(&ch_ctx->gr_ctx->mem)) {
                 /* reset patch count if ucode has already processed it */
                 ch_ctx->patch_ctx.data_count = nvgpu_mem_rd(g,
                                                 &ch_ctx->gr_ctx->mem,
@@ -699,7 +699,7 @@ void gr_gk20a_ctx_patch_write_end(struct gk20a *g,
         nvgpu_mem_end(g, &ch_ctx->patch_ctx.mem);
 
         /* Write context count to context image if it is mapped */
-        if (ch_ctx->gr_ctx->mem.cpu_va) {
+        if (nvgpu_mem_cpu_accessible(&ch_ctx->gr_ctx->mem)) {
                 nvgpu_mem_wr(g, &ch_ctx->gr_ctx->mem,
                              ctxsw_prog_main_image_patch_count_o(),
                              ch_ctx->patch_ctx.data_count);