Add lock and unlock flag support on command descriptor.
Once lock set in requester pipe, then the bam controller
will lock all others pipe and process the request only
from requester pipe. Unlocking only can be performed from
the same pipe.
If DMA_PREP_LOCK flag passed in command descriptor then requester
of this transaction wanted to lock the BAM controller for this
transaction so BAM driver should set LOCK bit for the HW descriptor.
If DMA_PREP_UNLOCK flag passed in command descriptor then requester
of this transaction wanted to unlock the BAM controller.so BAM driver
should set UNLOCK bit for the HW descriptor.
Signed-off-by: Md Sadre Alam <quic_mdalam@xxxxxxxxxxx>
---
drivers/dma/qcom/bam_dma.c | 10 ++++++++++
include/linux/dma/qcom_bam_dma.h | 2 ++
2 files changed, 12 insertions(+)
diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index 5e7d332731e0..146d78af3731 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -41,6 +41,7 @@
#include <linux/clk.h>
#include <linux/dmaengine.h>
#include <linux/pm_runtime.h>
+#include <linux/dma/qcom_bam_dma.h>
#include "../dmaengine.h"
#include "../virt-dma.h"
@@ -58,6 +59,8 @@ struct bam_desc_hw {
#define DESC_FLAG_EOB BIT(13)
#define DESC_FLAG_NWD BIT(12)
#define DESC_FLAG_CMD BIT(11)
+#define DESC_FLAG_LOCK BIT(10)
+#define DESC_FLAG_UNLOCK BIT(9)
struct bam_async_desc {
struct virt_dma_desc vd;
@@ -686,6 +689,13 @@ static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
/* fill in temporary descriptors */
desc = async_desc->desc;
+ if (flags & DMA_PREP_CMD) {
+ if (flags & DMA_PREP_LOCK)
+ desc->flags |= cpu_to_le16(DESC_FLAG_LOCK);
+ if (flags & DMA_PREP_UNLOCK)
+ desc->flags |= cpu_to_le16(DESC_FLAG_UNLOCK);
+ }
+
for_each_sg(sgl, sg, sg_len, i) {
unsigned int remainder = sg_dma_len(sg);
unsigned int curr_offset = 0;
diff --git a/include/linux/dma/qcom_bam_dma.h b/include/linux/dma/qcom_bam_dma.h
index 68fc0e643b1b..bc619c44ce82 100644
--- a/include/linux/dma/qcom_bam_dma.h
+++ b/include/linux/dma/qcom_bam_dma.h
@@ -8,6 +8,8 @@
#include <asm/byteorder.h>
+#define DMA_PREP_LOCK BIT(0)
+#define DMA_PREP_UNLOCK BIT(1)
/*
* This data type corresponds to the native Command Element
* supported by BAM DMA Engine.
--
2.34.1
