[PATCH 4/5] dmaengine: sprd: Add Spreadtrum DMA configuration

From: Baolin Wang
Date: Tue Apr 10 2018 - 03:46:55 EST


There are some Spreadtrum special configuration for DMA controller,
thus this patch adds one 'struct sprd_dma_config' structure for users
to configure.

Moreover this patch did some optimization for sprd_dma_config() and
sprd_dma_prep_dma_memcpy() to prepare to configure DMA from users.

Signed-off-by: Eric Long <eric.long@xxxxxxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
drivers/dma/sprd-dma.c | 262 ++++++++++++++++++++++++++++++++++--------
include/linux/dma/sprd-dma.h | 25 ++++
2 files changed, 238 insertions(+), 49 deletions(-)

diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index 5c26fde..f8038de 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -100,6 +100,8 @@
#define SPRD_DMA_DES_DATAWIDTH_OFFSET 28
#define SPRD_DMA_SWT_MODE_OFFSET 26
#define SPRD_DMA_REQ_MODE_OFFSET 24
+#define SPRD_DMA_WRAP_SEL_OFFSET 23
+#define SPRD_DMA_WRAP_EN_OFFSET 22
#define SPRD_DMA_REQ_MODE_MASK GENMASK(1, 0)
#define SPRD_DMA_FIX_SEL_OFFSET 21
#define SPRD_DMA_FIX_EN_OFFSET 20
@@ -173,6 +175,7 @@ struct sprd_dma_desc {
struct sprd_dma_chn {
struct virt_dma_chan vc;
void __iomem *chn_base;
+ struct sprd_dma_config slave_cfg;
u32 chn_num;
u32 dev_id;
struct sprd_dma_desc *cur_desc;
@@ -561,52 +564,162 @@ static void sprd_dma_issue_pending(struct dma_chan *chan)
spin_unlock_irqrestore(&schan->vc.lock, flags);
}

+static enum sprd_dma_datawidth
+sprd_dma_get_datawidth(enum dma_slave_buswidth buswidth)
+{
+ switch (buswidth) {
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ return SPRD_DMA_DATAWIDTH_1_BYTE;
+
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ return SPRD_DMA_DATAWIDTH_2_BYTES;
+
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ return SPRD_DMA_DATAWIDTH_4_BYTES;
+
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ return SPRD_DMA_DATAWIDTH_8_BYTES;
+
+ default:
+ return SPRD_DMA_DATAWIDTH_4_BYTES;
+ }
+}
+
+static int sprd_dma_get_step(enum dma_slave_buswidth buswidth,
+ enum dma_transfer_direction dir,
+ enum sprd_dma_step *src_step,
+ enum sprd_dma_step *dst_step)
+{
+ switch (dir) {
+ case DMA_MEM_TO_MEM:
+ switch (buswidth) {
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ *src_step = SPRD_DMA_BYTE_STEP;
+ *dst_step = SPRD_DMA_BYTE_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ *src_step = SPRD_DMA_SHORT_STEP;
+ *dst_step = SPRD_DMA_SHORT_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ *src_step = SPRD_DMA_WORD_STEP;
+ *dst_step = SPRD_DMA_WORD_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ *src_step = SPRD_DMA_DWORD_STEP;
+ *dst_step = SPRD_DMA_DWORD_STEP;
+ break;
+
+ default:
+ *src_step = SPRD_DMA_WORD_STEP;
+ *dst_step = SPRD_DMA_WORD_STEP;
+ break;
+ }
+ break;
+
+ case DMA_MEM_TO_DEV:
+ switch (buswidth) {
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ *src_step = SPRD_DMA_BYTE_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ *src_step = SPRD_DMA_SHORT_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ *src_step = SPRD_DMA_WORD_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ *src_step = SPRD_DMA_DWORD_STEP;
+ break;
+
+ default:
+ *src_step = SPRD_DMA_WORD_STEP;
+ break;
+ }
+
+ *dst_step = SPRD_DMA_NONE_STEP;
+ break;
+
+ case DMA_DEV_TO_MEM:
+ switch (buswidth) {
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ *dst_step = SPRD_DMA_BYTE_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ *dst_step = SPRD_DMA_SHORT_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ *dst_step = SPRD_DMA_WORD_STEP;
+ break;
+
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ *dst_step = SPRD_DMA_DWORD_STEP;
+ break;
+
+ default:
+ *dst_step = SPRD_DMA_WORD_STEP;
+ break;
+ }
+
+ *src_step = SPRD_DMA_NONE_STEP;
+ break;
+
+ case DMA_DEV_TO_DEV:
+ *src_step = SPRD_DMA_NONE_STEP;
+ *dst_step = SPRD_DMA_NONE_STEP;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static int sprd_dma_config(struct dma_chan *chan, struct sprd_dma_desc *sdesc,
- dma_addr_t dest, dma_addr_t src, size_t len)
+ struct sprd_dma_config *slave_cfg)
{
struct sprd_dma_dev *sdev = to_sprd_dma_dev(chan);
+ struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
struct sprd_dma_chn_hw *hw = &sdesc->chn_hw;
- u32 datawidth, src_step, des_step, fragment_len;
- u32 block_len, req_mode, irq_mode, transcation_len;
- u32 fix_mode = 0, fix_en = 0;
+ u32 fix_mode = 0, fix_en = 0, wrap_en = 0, wrap_mode = 0;
+ enum sprd_dma_step src_step, dst_step;
+ enum sprd_dma_datawidth src_datawidth, dst_datawidth;
+ int ret;

- if (IS_ALIGNED(len, 4)) {
- datawidth = SPRD_DMA_DATAWIDTH_4_BYTES;
- src_step = SPRD_DMA_WORD_STEP;
- des_step = SPRD_DMA_WORD_STEP;
- } else if (IS_ALIGNED(len, 2)) {
- datawidth = SPRD_DMA_DATAWIDTH_2_BYTES;
- src_step = SPRD_DMA_SHORT_STEP;
- des_step = SPRD_DMA_SHORT_STEP;
- } else {
- datawidth = SPRD_DMA_DATAWIDTH_1_BYTE;
- src_step = SPRD_DMA_BYTE_STEP;
- des_step = SPRD_DMA_BYTE_STEP;
+ ret = sprd_dma_get_step(slave_cfg->config.src_addr_width,
+ slave_cfg->config.direction,
+ &src_step, &dst_step);
+ if (ret) {
+ dev_err(sdev->dma_dev.dev, "invalid step values\n");
+ return ret;
}

- fragment_len = SPRD_DMA_MEMCPY_MIN_SIZE;
- if (len <= SPRD_DMA_BLK_LEN_MASK) {
- block_len = len;
- transcation_len = 0;
- req_mode = SPRD_DMA_BLK_REQ;
- irq_mode = SPRD_DMA_BLK_INT;
- } else {
- block_len = SPRD_DMA_MEMCPY_MIN_SIZE;
- transcation_len = len;
- req_mode = SPRD_DMA_TRANS_REQ;
- irq_mode = SPRD_DMA_TRANS_INT;
- }
+ if (slave_cfg->config.slave_id)
+ schan->dev_id = slave_cfg->config.slave_id;

hw->cfg = SPRD_DMA_DONOT_WAIT_BDONE << SPRD_DMA_WAIT_BDONE_OFFSET;
- hw->wrap_ptr = (u32)((src >> SPRD_DMA_HIGH_ADDR_OFFSET) &
- SPRD_DMA_HIGH_ADDR_MASK);
- hw->wrap_to = (u32)((dest >> SPRD_DMA_HIGH_ADDR_OFFSET) &
- SPRD_DMA_HIGH_ADDR_MASK);
-
- hw->src_addr = (u32)(src & SPRD_DMA_LOW_ADDR_MASK);
- hw->des_addr = (u32)(dest & SPRD_DMA_LOW_ADDR_MASK);
-
- if ((src_step != 0 && des_step != 0) || (src_step | des_step) == 0) {
+ hw->wrap_ptr = (u32)((slave_cfg->wrap_ptr & SPRD_DMA_LOW_ADDR_MASK) |
+ ((slave_cfg->config.src_addr >> SPRD_DMA_HIGH_ADDR_OFFSET) &
+ SPRD_DMA_HIGH_ADDR_MASK));
+ hw->wrap_to = (u32)((slave_cfg->wrap_to & SPRD_DMA_LOW_ADDR_MASK) |
+ ((slave_cfg->config.dst_addr >> SPRD_DMA_HIGH_ADDR_OFFSET) &
+ SPRD_DMA_HIGH_ADDR_MASK));
+
+ hw->src_addr =
+ (u32)(slave_cfg->config.src_addr & SPRD_DMA_LOW_ADDR_MASK);
+ hw->des_addr =
+ (u32)(slave_cfg->config.dst_addr & SPRD_DMA_LOW_ADDR_MASK);
+
+ if ((src_step != 0 && dst_step != 0) || (src_step | dst_step) == 0) {
fix_en = 0;
} else {
fix_en = 1;
@@ -616,17 +729,37 @@ static int sprd_dma_config(struct dma_chan *chan, struct sprd_dma_desc *sdesc,
fix_mode = 0;
}

- hw->frg_len = datawidth << SPRD_DMA_SRC_DATAWIDTH_OFFSET |
- datawidth << SPRD_DMA_DES_DATAWIDTH_OFFSET |
- req_mode << SPRD_DMA_REQ_MODE_OFFSET |
+ if (slave_cfg->wrap_ptr && slave_cfg->wrap_to) {
+ wrap_en = 1;
+ if (slave_cfg->wrap_to == slave_cfg->config.src_addr) {
+ wrap_mode = 0;
+ } else if (slave_cfg->wrap_to == slave_cfg->config.dst_addr) {
+ wrap_mode = 1;
+ } else {
+ dev_err(sdev->dma_dev.dev, "invalid wrap mode\n");
+ return -EINVAL;
+ }
+ }
+
+ src_datawidth =
+ sprd_dma_get_datawidth(slave_cfg->config.src_addr_width);
+ dst_datawidth =
+ sprd_dma_get_datawidth(slave_cfg->config.dst_addr_width);
+
+ hw->frg_len = src_datawidth << SPRD_DMA_SRC_DATAWIDTH_OFFSET |
+ dst_datawidth << SPRD_DMA_DES_DATAWIDTH_OFFSET |
+ slave_cfg->req_mode << SPRD_DMA_REQ_MODE_OFFSET |
+ wrap_mode << SPRD_DMA_WRAP_SEL_OFFSET |
+ wrap_en << SPRD_DMA_WRAP_EN_OFFSET |
fix_mode << SPRD_DMA_FIX_SEL_OFFSET |
fix_en << SPRD_DMA_FIX_EN_OFFSET |
- (fragment_len & SPRD_DMA_FRG_LEN_MASK);
- hw->blk_len = block_len & SPRD_DMA_BLK_LEN_MASK;
+ (slave_cfg->fragment_len & SPRD_DMA_FRG_LEN_MASK);
+
+ hw->blk_len = slave_cfg->block_len & SPRD_DMA_BLK_LEN_MASK;

hw->intc = SPRD_DMA_CFG_ERR_INT_EN;

- switch (irq_mode) {
+ switch (slave_cfg->int_mode) {
case SPRD_DMA_NO_INT:
break;

@@ -667,12 +800,13 @@ static int sprd_dma_config(struct dma_chan *chan, struct sprd_dma_desc *sdesc,
return -EINVAL;
}

- if (transcation_len == 0)
- hw->trsc_len = block_len & SPRD_DMA_TRSC_LEN_MASK;
+ if (slave_cfg->transcation_len == 0)
+ hw->trsc_len = slave_cfg->block_len & SPRD_DMA_TRSC_LEN_MASK;
else
- hw->trsc_len = transcation_len & SPRD_DMA_TRSC_LEN_MASK;
+ hw->trsc_len =
+ slave_cfg->transcation_len & SPRD_DMA_TRSC_LEN_MASK;

- hw->trsf_step = (des_step & SPRD_DMA_TRSF_STEP_MASK) <<
+ hw->trsf_step = (dst_step & SPRD_DMA_TRSF_STEP_MASK) <<
SPRD_DMA_DEST_TRSF_STEP_OFFSET |
(src_step & SPRD_DMA_TRSF_STEP_MASK) <<
SPRD_DMA_SRC_TRSF_STEP_OFFSET;
@@ -680,7 +814,6 @@ static int sprd_dma_config(struct dma_chan *chan, struct sprd_dma_desc *sdesc,
hw->frg_step = 0;
hw->src_blk_step = 0;
hw->des_blk_step = 0;
- hw->src_blk_step = 0;
return 0;
}

@@ -689,6 +822,7 @@ static int sprd_dma_config(struct dma_chan *chan, struct sprd_dma_desc *sdesc,
size_t len, unsigned long flags)
{
struct sprd_dma_chn *schan = to_sprd_dma_chan(chan);
+ struct sprd_dma_config *slave_cfg = &schan->slave_cfg;
struct sprd_dma_desc *sdesc;
int ret;

@@ -696,7 +830,37 @@ static int sprd_dma_config(struct dma_chan *chan, struct sprd_dma_desc *sdesc,
if (!sdesc)
return NULL;

- ret = sprd_dma_config(chan, sdesc, dest, src, len);
+ memset(slave_cfg, 0, sizeof(*slave_cfg));
+
+ slave_cfg->config.src_addr = src;
+ slave_cfg->config.dst_addr = dest;
+ slave_cfg->config.direction = DMA_MEM_TO_MEM;
+
+ if (IS_ALIGNED(len, 4)) {
+ slave_cfg->config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ slave_cfg->config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ } else if (IS_ALIGNED(len, 2)) {
+ slave_cfg->config.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ slave_cfg->config.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ } else {
+ slave_cfg->config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ slave_cfg->config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ }
+
+ slave_cfg->fragment_len = SPRD_DMA_MEMCPY_MIN_SIZE;
+ if (len <= SPRD_DMA_BLK_LEN_MASK) {
+ slave_cfg->block_len = len;
+ slave_cfg->transcation_len = 0;
+ slave_cfg->req_mode = SPRD_DMA_BLK_REQ;
+ slave_cfg->int_mode = SPRD_DMA_BLK_INT;
+ } else {
+ slave_cfg->block_len = SPRD_DMA_MEMCPY_MIN_SIZE;
+ slave_cfg->transcation_len = len;
+ slave_cfg->req_mode = SPRD_DMA_TRANS_REQ;
+ slave_cfg->int_mode = SPRD_DMA_TRANS_INT;
+ }
+
+ ret = sprd_dma_config(chan, sdesc, slave_cfg);
if (ret) {
kfree(sdesc);
return NULL;
diff --git a/include/linux/dma/sprd-dma.h b/include/linux/dma/sprd-dma.h
index c545162..8bda7d7 100644
--- a/include/linux/dma/sprd-dma.h
+++ b/include/linux/dma/sprd-dma.h
@@ -3,6 +3,8 @@
#ifndef _SPRD_DMA_H_
#define _SPRD_DMA_H_

+#include <linux/dmaengine.h>
+
/*
* enum sprd_dma_req_mode: define the DMA request mode
* @SPRD_DMA_FRAG_REQ: fragment request mode
@@ -54,4 +56,27 @@ enum sprd_dma_int_type {
SPRD_DMA_CFGERR_INT,
};

+/*
+ * struct sprd_dma_config - DMA configuration structure
+ * @config: dma slave channel config
+ * @fragment_len: specify one fragment transfer length
+ * @block_len: specify one block transfer length
+ * @transcation_len: specify one transcation transfer length
+ * @wrap_ptr: wrap pointer address, once the transfer address reaches the
+ * 'wrap_ptr', the next transfer address will jump to the 'wrap_to' address.
+ * @wrap_to: wrap jump to address
+ * @req_mode: specify the DMA request mode
+ * @int_mode: specify the DMA interrupt type
+ */
+struct sprd_dma_config {
+ struct dma_slave_config config;
+ u32 fragment_len;
+ u32 block_len;
+ u32 transcation_len;
+ phys_addr_t wrap_ptr;
+ phys_addr_t wrap_to;
+ enum sprd_dma_req_mode req_mode;
+ enum sprd_dma_int_type int_mode;
+};
+
#endif
--
1.7.9.5