[PATCH 1/6] dmaengine: tegra210-adma: prepare for supporting newer Tegra chips

From: Sameer Pujar
Date: Thu May 02 2019 - 08:55:59 EST


This is a preparatory patch to add support for Tegra186 and Tegra194 chips.
Following changes are necessary to make driver code generic.
* chip_data structure is enhanced to have chip specific details and
following are the additions to the structure
* Offset addresses for ADMA global and channel registers
* Offset values for Tx and Rx channel selection
* Maximum supported Tx and Rx channels
* Tx and Rx channel request mask
* ADMA channel register space size
* Make use of above chip_data to generalise the driver code

Support for Tegra186 and Tegra194 will be added in subsequent patches of
the series.

Signed-off-by: Sameer Pujar <spujar@xxxxxxxxxx>
---
drivers/dma/tegra210-adma.c | 91 ++++++++++++++++++++++++++++-----------------
1 file changed, 57 insertions(+), 34 deletions(-)

diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c
index 253d312..9aee015 100644
--- a/drivers/dma/tegra210-adma.c
+++ b/drivers/dma/tegra210-adma.c
@@ -36,10 +36,6 @@

#define ADMA_CH_INT_CLEAR 0x1c
#define ADMA_CH_CTRL 0x24
-#define ADMA_CH_CTRL_TX_REQ(val) (((val) & 0xf) << 28)
-#define ADMA_CH_CTRL_TX_REQ_MAX 10
-#define ADMA_CH_CTRL_RX_REQ(val) (((val) & 0xf) << 24)
-#define ADMA_CH_CTRL_RX_REQ_MAX 10
#define ADMA_CH_CTRL_DIR(val) (((val) & 0xf) << 12)
#define ADMA_CH_CTRL_DIR_AHUB2MEM 2
#define ADMA_CH_CTRL_DIR_MEM2AHUB 4
@@ -57,8 +53,8 @@
#define ADMA_CH_FIFO_CTRL 0x2c
#define ADMA_CH_FIFO_CTRL_OVRFW_THRES(val) (((val) & 0xf) << 24)
#define ADMA_CH_FIFO_CTRL_STARV_THRES(val) (((val) & 0xf) << 16)
-#define ADMA_CH_FIFO_CTRL_TX_SIZE(val) (((val) & 0xf) << 8)
-#define ADMA_CH_FIFO_CTRL_RX_SIZE(val) ((val) & 0xf)
+#define ADMA_CH_FIFO_CTRL_TX_FIFO_SIZE_SHIFT 8
+#define ADMA_CH_FIFO_CTRL_RX_FIFO_SIZE_SHIFT 0

#define ADMA_CH_LOWER_SRC_ADDR 0x34
#define ADMA_CH_LOWER_TRG_ADDR 0x3c
@@ -68,25 +64,38 @@
#define ADMA_CH_XFER_STATUS 0x54
#define ADMA_CH_XFER_STATUS_COUNT_MASK 0xffff

-#define ADMA_GLOBAL_CMD 0xc00
-#define ADMA_GLOBAL_SOFT_RESET 0xc04
-#define ADMA_GLOBAL_INT_CLEAR 0xc20
-#define ADMA_GLOBAL_CTRL 0xc24
-
-#define ADMA_CH_REG_OFFSET(a) (a * 0x80)
+#define ADMA_GLOBAL_CMD 0x00
+#define ADMA_GLOBAL_SOFT_RESET 0x04

#define ADMA_CH_FIFO_CTRL_DEFAULT (ADMA_CH_FIFO_CTRL_OVRFW_THRES(1) | \
- ADMA_CH_FIFO_CTRL_STARV_THRES(1) | \
- ADMA_CH_FIFO_CTRL_TX_SIZE(3) | \
- ADMA_CH_FIFO_CTRL_RX_SIZE(3))
+ ADMA_CH_FIFO_CTRL_STARV_THRES(1))
+
+#define ADMA_CH_REG_FIELD_VAL(val, mask, shift) (((val) & mask) << shift)
+
struct tegra_adma;

/*
* struct tegra_adma_chip_data - Tegra chip specific data
+ * @global_reg_offset: Register offset of DMA global register.
+ * @global_int_clear: Register offset of DMA global interrupt clear.
+ * @ch_req_tx_shift: Register offset for AHUB transmit channel select.
+ * @ch_req_rx_shift: Register offset for AHUB receive channel select.
+ * @ch_base_offset: Reister offset of DMA channel registers.
+ * @ch_req_mask: Mask for Tx or Rx channel select.
+ * @ch_req_max: Maximum number of Tx or Rx channels available.
+ * @ch_reg_size: Size of DMA channel register space.
* @nr_channels: Number of DMA channels available.
*/
struct tegra_adma_chip_data {
- int nr_channels;
+ unsigned int global_reg_offset;
+ unsigned int global_int_clear;
+ unsigned int ch_req_tx_shift;
+ unsigned int ch_req_rx_shift;
+ unsigned int ch_base_offset;
+ unsigned int ch_req_mask;
+ unsigned int ch_req_max;
+ unsigned int ch_reg_size;
+ unsigned int nr_channels;
};

/*
@@ -148,18 +157,20 @@ struct tegra_adma {
/* Used to store global command register state when suspending */
unsigned int global_cmd;

+ const struct tegra_adma_chip_data *cdata;
+
/* Last member of the structure */
struct tegra_adma_chan channels[0];
};

static inline void tdma_write(struct tegra_adma *tdma, u32 reg, u32 val)
{
- writel(val, tdma->base_addr + reg);
+ writel(val, tdma->base_addr + tdma->cdata->global_reg_offset + reg);
}

static inline u32 tdma_read(struct tegra_adma *tdma, u32 reg)
{
- return readl(tdma->base_addr + reg);
+ return readl(tdma->base_addr + tdma->cdata->global_reg_offset + reg);
}

static inline void tdma_ch_write(struct tegra_adma_chan *tdc, u32 reg, u32 val)
@@ -209,14 +220,16 @@ static int tegra_adma_init(struct tegra_adma *tdma)
int ret;

/* Clear any interrupts */
- tdma_write(tdma, ADMA_GLOBAL_INT_CLEAR, 0x1);
+ tdma_write(tdma, tdma->cdata->global_int_clear, 0x1);

/* Assert soft reset */
tdma_write(tdma, ADMA_GLOBAL_SOFT_RESET, 0x1);

/* Wait for reset to clear */
ret = readx_poll_timeout(readl,
- tdma->base_addr + ADMA_GLOBAL_SOFT_RESET,
+ tdma->base_addr +
+ tdma->cdata->global_reg_offset +
+ ADMA_GLOBAL_SOFT_RESET,
status, status == 0, 20, 10000);
if (ret)
return ret;
@@ -236,13 +249,13 @@ static int tegra_adma_request_alloc(struct tegra_adma_chan *tdc,
if (tdc->sreq_reserved)
return tdc->sreq_dir == direction ? 0 : -EINVAL;

+ if (sreq_index > tdma->cdata->ch_req_max) {
+ dev_err(tdma->dev, "invalid DMA request\n");
+ return -EINVAL;
+ }
+
switch (direction) {
case DMA_MEM_TO_DEV:
- if (sreq_index > ADMA_CH_CTRL_TX_REQ_MAX) {
- dev_err(tdma->dev, "invalid DMA request\n");
- return -EINVAL;
- }
-
if (test_and_set_bit(sreq_index, &tdma->tx_requests_reserved)) {
dev_err(tdma->dev, "DMA request reserved\n");
return -EINVAL;
@@ -250,11 +263,6 @@ static int tegra_adma_request_alloc(struct tegra_adma_chan *tdc,
break;

case DMA_DEV_TO_MEM:
- if (sreq_index > ADMA_CH_CTRL_RX_REQ_MAX) {
- dev_err(tdma->dev, "invalid DMA request\n");
- return -EINVAL;
- }
-
if (test_and_set_bit(sreq_index, &tdma->rx_requests_reserved)) {
dev_err(tdma->dev, "DMA request reserved\n");
return -EINVAL;
@@ -487,6 +495,7 @@ static int tegra_adma_set_xfer_params(struct tegra_adma_chan *tdc,
enum dma_transfer_direction direction)
{
struct tegra_adma_chan_regs *ch_regs = &desc->ch_regs;
+ const struct tegra_adma_chip_data *cdata = tdc->tdma->cdata;
unsigned int burst_size, adma_dir;

if (desc->num_periods > ADMA_CH_CONFIG_MAX_BUFS)
@@ -497,7 +506,9 @@ static int tegra_adma_set_xfer_params(struct tegra_adma_chan *tdc,
adma_dir = ADMA_CH_CTRL_DIR_MEM2AHUB;
burst_size = fls(tdc->sconfig.dst_maxburst);
ch_regs->config = ADMA_CH_CONFIG_SRC_BUF(desc->num_periods - 1);
- ch_regs->ctrl = ADMA_CH_CTRL_TX_REQ(tdc->sreq_index);
+ ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
+ cdata->ch_req_mask,
+ cdata->ch_req_tx_shift);
ch_regs->src_addr = buf_addr;
break;

@@ -505,7 +516,9 @@ static int tegra_adma_set_xfer_params(struct tegra_adma_chan *tdc,
adma_dir = ADMA_CH_CTRL_DIR_AHUB2MEM;
burst_size = fls(tdc->sconfig.src_maxburst);
ch_regs->config = ADMA_CH_CONFIG_TRG_BUF(desc->num_periods - 1);
- ch_regs->ctrl = ADMA_CH_CTRL_RX_REQ(tdc->sreq_index);
+ ch_regs->ctrl = ADMA_CH_REG_FIELD_VAL(tdc->sreq_index,
+ cdata->ch_req_mask,
+ cdata->ch_req_rx_shift);
ch_regs->trg_addr = buf_addr;
break;

@@ -658,7 +671,15 @@ static int tegra_adma_runtime_resume(struct device *dev)
}

static const struct tegra_adma_chip_data tegra210_chip_data = {
- .nr_channels = 22,
+ .global_reg_offset = 0xc00,
+ .global_int_clear = 0x20,
+ .ch_req_tx_shift = 28,
+ .ch_req_rx_shift = 24,
+ .ch_base_offset = 0,
+ .ch_req_mask = 0xf,
+ .ch_req_max = 10,
+ .ch_reg_size = 0x80,
+ .nr_channels = 22,
};

static const struct of_device_id tegra_adma_of_match[] = {
@@ -687,6 +708,7 @@ static int tegra_adma_probe(struct platform_device *pdev)
return -ENOMEM;

tdma->dev = &pdev->dev;
+ tdma->cdata = cdata;
tdma->nr_channels = cdata->nr_channels;
platform_set_drvdata(pdev, tdma);

@@ -715,7 +737,8 @@ static int tegra_adma_probe(struct platform_device *pdev)
for (i = 0; i < tdma->nr_channels; i++) {
struct tegra_adma_chan *tdc = &tdma->channels[i];

- tdc->chan_addr = tdma->base_addr + ADMA_CH_REG_OFFSET(i);
+ tdc->chan_addr = tdma->base_addr + cdata->ch_base_offset
+ + (cdata->ch_reg_size * i);

tdc->irq = of_irq_get(pdev->dev.of_node, i);
if (tdc->irq <= 0) {
--
2.7.4