[PATCH net-next 1/8] MIPS: lantiq: dma: add small delay after reset

From: Aleksander Jan Bajkowski
Date: Tue Sep 14 2021 - 17:21:45 EST


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@xxxxx>
---
arch/mips/lantiq/xway/dma.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/mips/lantiq/xway/dma.c b/arch/mips/lantiq/xway/dma.c
index 63dccb2ed08b..2784715933d1 100644
--- a/arch/mips/lantiq/xway/dma.c
+++ b/arch/mips/lantiq/xway/dma.c
@@ -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 <linux/of.h>

@@ -222,6 +223,8 @@ 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);

--
2.30.2