[PATCH v4 04/20] mtd: nand: qcom: add and initialize QPIC DMA resources

Abhishek Sahu
2017-08-11T11:40:12Z

1. QPIC NAND controller uses 3 BAM channels: command, data tx
and data rx while EBI2 NAND controller uses only single ADM
channel.
2. CRCI is only required for ADM DMA and it's not required for
BAM DMA.

Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
---
drivers/mtd/nand/qcom_nandc.c | 86 ++++++++++++++++++++++++++++++++++---------
1 file changed, 68 insertions(+), 18 deletions(-)

diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c
index 2d44eeb..59b764a 100644
--- a/drivers/mtd/nand/qcom_nandc.c
+++ b/drivers/mtd/nand/qcom_nandc.c
@@ -255,9 +255,22 @@ struct qcom_nand_controller {
struct clk *core_clk;
struct clk *aon_clk;

- struct dma_chan *chan;
- unsigned int cmd_crci;
- unsigned int data_crci;
+ union {
+ /* will be used only by QPIC for BAM DMA */
+ struct {
+ struct dma_chan *tx_chan;
+ struct dma_chan *rx_chan;
+ struct dma_chan *cmd_chan;
+ };
+
+ /* will be used only by EBI2 for ADM DMA */
+ struct {
+ struct dma_chan *chan;
+ unsigned int cmd_crci;
+ unsigned int data_crci;
+ };
+ };
+
struct list_head desc_list;

u8 *data_buffer;
@@ -1989,10 +2002,31 @@ static int qcom_nandc_alloc(struct qcom_nand_controller *nandc)
if (!nandc->reg_read_buf)
return -ENOMEM;

- nandc->chan = dma_request_slave_channel(nandc->dev, "rxtx");
- if (!nandc->chan) {
- dev_err(nandc->dev, "failed to request slave channel\n");
- return -ENODEV;
+ if (nandc->props->is_bam) {
+ nandc->tx_chan = dma_request_slave_channel(nandc->dev, "tx");
+ if (!nandc->tx_chan) {
+ dev_err(nandc->dev, "failed to request tx channel\n");
+ return -ENODEV;
+ }
+
+ nandc->rx_chan = dma_request_slave_channel(nandc->dev, "rx");
+ if (!nandc->rx_chan) {
+ dev_err(nandc->dev, "failed to request rx channel\n");
+ return -ENODEV;
+ }
+
+ nandc->cmd_chan = dma_request_slave_channel(nandc->dev, "cmd");
+ if (!nandc->cmd_chan) {
+ dev_err(nandc->dev, "failed to request cmd channel\n");
+ return -ENODEV;
+ }
+ } else {
+ nandc->chan = dma_request_slave_channel(nandc->dev, "rxtx");
+ if (!nandc->chan) {
+ dev_err(nandc->dev,
+ "failed to request slave channel\n");
+ return -ENODEV;
+ }
}

INIT_LIST_HEAD(&nandc->desc_list);
@@ -2005,7 +2039,19 @@ static int qcom_nandc_alloc(struct qcom_nand_controller *nandc)

static void qcom_nandc_unalloc(struct qcom_nand_controller *nandc)
{
- dma_release_channel(nandc->chan);
+ if (nandc->props->is_bam) {
+ if (nandc->tx_chan)
+ dma_release_channel(nandc->tx_chan);
+
+ if (nandc->rx_chan)
+ dma_release_channel(nandc->rx_chan);
+
+ if (nandc->cmd_chan)
+ dma_release_channel(nandc->cmd_chan);
+ } else {
+ if (nandc->chan)
+ dma_release_channel(nandc->chan);
+ }
}

/* one time setup of a few nand controller registers */
@@ -2146,16 +2192,20 @@ static int qcom_nandc_parse_dt(struct platform_device *pdev)
struct device_node *np = nandc->dev->of_node;
int ret;

- ret = of_property_read_u32(np, "qcom,cmd-crci", &nandc->cmd_crci);
- if (ret) {
- dev_err(nandc->dev, "command CRCI unspecified\n");
- return ret;
- }
+ if (!nandc->props->is_bam) {
+ ret = of_property_read_u32(np, "qcom,cmd-crci",
+ &nandc->cmd_crci);
+ if (ret) {
+ dev_err(nandc->dev, "command CRCI unspecified\n");
+ return ret;
+ }

- ret = of_property_read_u32(np, "qcom,data-crci", &nandc->data_crci);
- if (ret) {
- dev_err(nandc->dev, "data CRCI unspecified\n");
- return ret;
+ ret = of_property_read_u32(np, "qcom,data-crci",
+ &nandc->data_crci);
+ if (ret) {
+ dev_err(nandc->dev, "data CRCI unspecified\n");
+ return ret;
+ }
}

return 0;
@@ -2205,7 +2255,7 @@ static int qcom_nandc_probe(struct platform_device *pdev)

ret = qcom_nandc_alloc(nandc);
if (ret)
- return ret;
+ goto err_core_clk;

ret = clk_prepare_enable(nandc->core_clk);
if (ret)