misc: fastrpc: make sure memory read and writes are visible
dma_alloc_coherent buffers could have writes queued in store buffers so
commit them before sending buffer to DSP using correct dma barriers.
Same with vice-versa.
Fixes: c68cfb718c8f ("misc: fastrpc: Add support for context Invoke method")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
index ecb5664..986c9ae 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -792,6 +792,9 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel,
if (err)
goto bail;
}
+
+ /* make sure that all CPU memory writes are seen by DSP */
+ dma_wmb();
/* Send invoke buffer to remote dsp */
err = fastrpc_invoke_send(fl->sctx, ctx, kernel, handle);
if (err)
@@ -808,6 +811,8 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel,
goto bail;
if (ctx->nscalars) {
+ /* make sure that all memory writes by DSP are seen by CPU */
+ dma_rmb();
/* populate all the output buffers with results */
err = fastrpc_put_args(ctx, kernel);
if (err)