[PATCH v3 5/9] dmaengine: sun6i: make gate bit in sun8i's DMA engines a common quirk
Icenowy Zheng
icenowy at aosc.io
Wed May 24 03:06:03 PDT 2017
From: Icenowy Zheng <icenowy at aosc.xyz>
Originally we enable a special gate bit when the compatible indicates
A23/33.
But according to BSP sources and user manuals, more SoCs will need this
gate bit.
So make it a common quirk configured in the config struct.
Signed-off-by: Icenowy Zheng <icenowy at aosc.xyz>
---
Changes in v3:
- Stripped out the A83T gate bit set.
drivers/dma/sun6i-dma.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c
index a2358780ab2c..69840cf6fe98 100644
--- a/drivers/dma/sun6i-dma.c
+++ b/drivers/dma/sun6i-dma.c
@@ -101,6 +101,11 @@ struct sun6i_dma_config {
u32 nr_max_channels;
u32 nr_max_requests;
u32 nr_max_vchans;
+ /*
+ * The hardware has a special gate bit, which is needed to
+ * be enabled for some SoCs with a sun6i-style DMA engine.
+ */
+ bool gate_needed;
};
/*
@@ -1009,6 +1014,7 @@ static struct sun6i_dma_config sun8i_a23_dma_cfg = {
.nr_max_channels = 8,
.nr_max_requests = 24,
.nr_max_vchans = 37,
+ .gate_needed = true,
};
static struct sun6i_dma_config sun8i_a83t_dma_cfg = {
@@ -1177,10 +1183,10 @@ static int sun6i_dma_probe(struct platform_device *pdev)
/*
* sun8i variant requires us to toggle a dma gating register,
* as seen in Allwinner's SDK. This register is not documented
- * in the A23 user manual.
+ * in the A23 user manual, but documented at least in V3s user
+ * manual.
*/
- if (of_device_is_compatible(pdev->dev.of_node,
- "allwinner,sun8i-a23-dma"))
+ if (sdc->cfg->gate_needed)
writel(SUN8I_DMA_GATE_ENABLE, sdc->base + SUN8I_DMA_GATE);
return 0;
--
2.12.2
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