dmaengine: dw-edma: HDMA: Add sync read before starting the DMA transfer in remote setup

[ Upstream commit 712a92a4 ]

The Linked list element and pointer are not stored in the same memory as
the HDMA controller register. If the doorbell register is toggled before
the full write of the linked list a race condition error will occur.
In remote setup we can only use a readl to the memory to assure the full
write has occurred.

Fixes: e74c3957

 ("dmaengine: dw-edma: Add support for native HDMA")
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://lore.kernel.org/r/20240129-b4-feature_hdma_mainline-v7-5-8e8c1acb7a46@bootlin.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>