Commit ca07aff2 authored Sep 14, 2021 by Aleksander Jan Bajkowski Committed by Greg Kroah-Hartman Nov 17, 2021

MIPS: lantiq: dma: add small delay after reset



[ Upstream commit c12aa581f6d5e80c3c3675ab26a52c2b3b62f76e ]

Reading the DMA registers immediately after the reset causes
Data Bus Error. Adding a small delay fixes this issue.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent e5ea3dca

arch/mips/lantiq/xway/dma.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -11,6 +11,7 @@
		#include <linux/export.h>
		#include <linux/spinlock.h>
		#include <linux/clk.h>
		#include <linux/delay.h>
		#include <linux/err.h>

		#include <lantiq_soc.h>
		@@ -221,6 +222,8 @@ ltq_dma_init(struct platform_device *pdev)
		clk_enable(clk);
		ltq_dma_w32_mask(0, DMA_RESET, LTQ_DMA_CTRL);

		usleep_range(1, 10);

		/* disable all interrupts */
		ltq_dma_w32(0, LTQ_DMA_IRNEN);