From 5a7ccdf845d64b385affdcffaf2defbe9848be15 Mon Sep 17 00:00:00 2001
From: Ram Chandra Jangir <rjangir@codeaurora.org>
Date: Thu, 20 Apr 2017 10:39:00 +0530
Subject: [PATCH] dmaengine: qcom: bam_dma: Add custom data mapping
Add a new function to support for preparing DMA descriptor
for custom data.
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Ram Chandra Jangir <rjangir@codeaurora.org>
---
drivers/dma/qcom/bam_dma.c | 97 +++++++++++++++++++++++++++++++++++++---
include/linux/dma/qcom_bam_dma.h | 14 ++++++
include/linux/dmaengine.h | 14 ++++++
3 files changed, 119 insertions(+), 6 deletions(-)
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -49,6 +49,7 @@
#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"
@@ -61,11 +62,6 @@ struct bam_desc_hw {
#define BAM_DMA_AUTOSUSPEND_DELAY 100
-#define DESC_FLAG_INT BIT(15)
-#define DESC_FLAG_EOT BIT(14)
-#define DESC_FLAG_EOB BIT(13)
-#define DESC_FLAG_NWD BIT(12)
-
struct bam_async_desc {
struct virt_dma_desc vd;
@@ -670,6 +666,93 @@ err_out:
}
/**
+ * bam_prep_dma_custom_mapping - Prep DMA descriptor from custom data
+ *
+ * @chan: dma channel
+ * @data: custom data
+ * @flags: DMA flags
+ */
+static struct dma_async_tx_descriptor *bam_prep_dma_custom_mapping(
+ struct dma_chan *chan,
+ void *data, unsigned long flags)
+{
+ struct bam_chan *bchan = to_bam_chan(chan);
+ struct bam_device *bdev = bchan->bdev;
+ struct bam_async_desc *async_desc;
+ struct qcom_bam_custom_data *desc_data = data;
+ u32 i;
+ struct bam_desc_hw *desc;
+ unsigned int num_alloc = 0;
+
+
+ if (!is_slave_direction(desc_data->dir)) {
+ dev_err(bdev->dev, "invalid dma direction\n");
+ return NULL;
+ }
+
+ /* calculate number of required entries */
+ for (i = 0; i < desc_data->sgl_cnt; i++)
+ num_alloc += DIV_ROUND_UP(
+ sg_dma_len(&desc_data->bam_sgl[i].sgl), BAM_FIFO_SIZE);
+
+ /* allocate enough room to accommodate the number of entries */
+ async_desc = kzalloc(sizeof(*async_desc) +
+ (num_alloc * sizeof(struct bam_desc_hw)), GFP_NOWAIT);
+
+ if (!async_desc)
+ goto err_out;
+
+ if (flags & DMA_PREP_FENCE)
+ async_desc->flags |= DESC_FLAG_NWD;
+
+ if (flags & DMA_PREP_INTERRUPT)
+ async_desc->flags |= DESC_FLAG_EOT;
+ else
+ async_desc->flags |= DESC_FLAG_INT;
+
+ async_desc->num_desc = num_alloc;
+ async_desc->curr_desc = async_desc->desc;
+ async_desc->dir = desc_data->dir;
+
+ /* fill in temporary descriptors */
+ desc = async_desc->desc;
+ for (i = 0; i < desc_data->sgl_cnt; i++) {
+ unsigned int remainder;
+ unsigned int curr_offset = 0;
+
+ remainder = sg_dma_len(&desc_data->bam_sgl[i].sgl);
+
+ do {
+ desc->addr = cpu_to_le32(
+ sg_dma_address(&desc_data->bam_sgl[i].sgl) +
+ curr_offset);
+
+ if (desc_data->bam_sgl[i].dma_flags)
+ desc->flags |= cpu_to_le16(
+ desc_data->bam_sgl[i].dma_flags);
+
+ if (remainder > BAM_FIFO_SIZE) {
+ desc->size = cpu_to_le16(BAM_FIFO_SIZE);
+ remainder -= BAM_FIFO_SIZE;
+ curr_offset += BAM_FIFO_SIZE;
+ } else {
+ desc->size = cpu_to_le16(remainder);
+ remainder = 0;
+ }
+
+ async_desc->length += desc->size;
+ desc++;
+ } while (remainder > 0);
+ }
+
+ return vchan_tx_prep(&bchan->vc, &async_desc->vd, flags);
+
+err_out:
+ kfree(async_desc);
+ return NULL;
+}
+
+/**
* bam_dma_terminate_all - terminate all transactions on a channel
* @bchan: bam dma channel
*
@@ -960,7 +1043,7 @@ static void bam_start_dma(struct bam_cha
/* set any special flags on the last descriptor */
if (async_desc->num_desc == async_desc->xfer_len)
- desc[async_desc->xfer_len - 1].flags =
+ desc[async_desc->xfer_len - 1].flags |=
cpu_to_le16(async_desc->flags);
else
desc[async_desc->xfer_len - 1].flags |=
@@ -1237,6 +1320,8 @@ static int bam_dma_probe(struct platform
bdev->common.device_alloc_chan_resources = bam_alloc_chan;
bdev->common.device_free_chan_resources = bam_free_chan;
bdev->common.device_prep_slave_sg = bam_prep_slave_sg;
+ bdev->common.device_prep_dma_custom_mapping =
+ bam_prep_dma_custom_mapping;
bdev->common.device_config = bam_slave_config;
bdev->common.device_pause = bam_pause;
bdev->common.device_resume = bam_resume;
--- a/include/linux/dma/qcom_bam_dma.h
+++ b/include/linux/dma/qcom_bam_dma.h
@@ -65,6 +65,19 @@ enum bam_command_type {
};
/*
+ * QCOM BAM DMA custom data
+ *
+ * @sgl_cnt: number of sgl in bam_sgl
+ * @dir: DMA data transfer direction
+ * @bam_sgl: BAM SGL pointer
+ */
+struct qcom_bam_custom_data {
+ u32 sgl_cnt;
+ enum dma_transfer_direction dir;
+ struct qcom_bam_sgl *bam_sgl;
+};
+
+/*
* qcom_bam_sg_init_table - Init QCOM BAM SGL
* @bam_sgl: bam sgl
* @nents: number of entries in bam sgl
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -692,6 +692,8 @@ struct dma_filter {
* be called after period_len bytes have been transferred.
* @device_prep_interleaved_dma: Transfer expression in a generic way.
* @device_prep_dma_imm_data: DMA's 8 byte immediate data to the dst address
+ * @device_prep_dma_custom_mapping: prepares a dma operation from dma driver
+ * specific custom data
* @device_config: Pushes a new configuration to a channel, return 0 or an error
* code
* @device_pause: Pauses any transfer happening on a channel. Returns
@@ -783,6 +785,9 @@ struct dma_device {
struct dma_async_tx_descriptor *(*device_prep_dma_imm_data)(
struct dma_chan *chan, dma_addr_t dst, u64 data,
unsigned long flags);
+ struct dma_async_tx_descriptor *(*device_prep_dma_custom_mapping)(
+ struct dma_chan *chan, void *data,
+ unsigned long flags);
int (*device_config)(struct dma_chan *chan,
struct dma_slave_config *config);
@@ -899,6 +904,15 @@ static inline struct dma_async_tx_descri
src_sg, src_nents, flags);
}
+static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_custom_mapping(
+ struct dma_chan *chan,
+ void *data,
+ unsigned long flags)
+{
+ return chan->device->device_prep_dma_custom_mapping(chan, data,
+ flags);
+}
+
/**
* dmaengine_terminate_all() - Terminate all active DMA transfers
* @chan: The channel for which to terminate the transfers