Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx>
---
drivers/mtd/nand/qcom_nandc.c | 40 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 40 insertions(+)
diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c
index 59b764a..590fc1d 100644
--- a/drivers/mtd/nand/qcom_nandc.c
+++ b/drivers/mtd/nand/qcom_nandc.c
@@ -234,6 +234,7 @@ struct nandc_regs {
* by upper layers directly
* @buf_size/count/start: markers for chip->read_buf/write_buf functions
* @reg_read_buf: local buffer for reading back registers via DMA
+ * @reg_read_dma: contains dma address for register read buffer
* @reg_read_pos: marker for data read in reg_read_buf
*
* @regs: a contiguous chunk of memory for DMA register
@@ -279,6 +280,7 @@ struct qcom_nand_controller {
int buf_start;
__le32 *reg_read_buf;
+ dma_addr_t reg_read_dma;
int reg_read_pos;
struct nandc_regs *regs;
@@ -371,6 +373,24 @@ static inline void nandc_write(struct qcom_nand_controller *nandc, int offset,
iowrite32(val, nandc->base + offset);
}
+static inline void nandc_read_buffer_sync(struct qcom_nand_controller *nandc,
+ bool is_cpu)
+{
+ if (!nandc->props->is_bam)
+ return;
+
+ if (is_cpu)
+ dma_sync_single_for_cpu(nandc->dev, nandc->reg_read_dma,
+ MAX_REG_RD *
+ sizeof(*nandc->reg_read_buf),
+ DMA_FROM_DEVICE);
+ else
+ dma_sync_single_for_device(nandc->dev, nandc->reg_read_dma,
+ MAX_REG_RD *
+ sizeof(*nandc->reg_read_buf),
+ DMA_FROM_DEVICE);
+}
+
static __le32 *offset_to_nandc_reg(struct nandc_regs *regs, int offset)
{
switch (offset) {
@@ -854,6 +874,7 @@ static void free_descs(struct qcom_nand_controller *nandc)
static void clear_read_regs(struct qcom_nand_controller *nandc)
{
nandc->reg_read_pos = 0;
+ nandc_read_buffer_sync(nandc, false);
}
static void pre_command(struct qcom_nand_host *host, int command)
@@ -883,6 +904,7 @@ static void parse_erase_write_errors(struct qcom_nand_host *host, int command)
int i;
num_cw = command == NAND_CMD_PAGEPROG ? ecc->steps : 1;
+ nandc_read_buffer_sync(nandc, true);
for (i = 0; i < num_cw; i++) {
u32 flash_status = le32_to_cpu(nandc->reg_read_buf[i]);
@@ -904,6 +926,7 @@ static void post_command(struct qcom_nand_host *host, int command)
switch (command) {
case NAND_CMD_READID:
+ nandc_read_buffer_sync(nandc, true);
memcpy(nandc->data_buffer, nandc->reg_read_buf,
nandc->buf_count);
break;
@@ -1067,6 +1090,7 @@ static int parse_read_errors(struct qcom_nand_host *host, u8 *data_buf,
int i;
buf = (struct read_stats *)nandc->reg_read_buf;
+ nandc_read_buffer_sync(nandc, true);
for (i = 0; i < ecc->steps; i++, buf++) {
u32 flash, buffer, erased_cw;
@@ -2003,6 +2027,16 @@ static int qcom_nandc_alloc(struct qcom_nand_controller *nandc)
return -ENOMEM;
if (nandc->props->is_bam) {
+ nandc->reg_read_dma =
+ dma_map_single(nandc->dev, nandc->reg_read_buf,
+ MAX_REG_RD *
+ sizeof(*nandc->reg_read_buf),
+ DMA_FROM_DEVICE);
+ if (dma_mapping_error(nandc->dev, nandc->reg_read_dma)) {
+ dev_err(nandc->dev, "failed to DMA MAP reg buffer\n");
+ return -EIO;
+ }
+
nandc->tx_chan = dma_request_slave_channel(nandc->dev, "tx");
if (!nandc->tx_chan) {
dev_err(nandc->dev, "failed to request tx channel\n");
@@ -2040,6 +2074,12 @@ static int qcom_nandc_alloc(struct qcom_nand_controller *nandc)
static void qcom_nandc_unalloc(struct qcom_nand_controller *nandc)
{
if (nandc->props->is_bam) {
+ if (!dma_mapping_error(nandc->dev, nandc->reg_read_dma))
+ dma_unmap_single(nandc->dev, nandc->reg_read_dma,
+ MAX_REG_RD *
+ sizeof(*nandc->reg_read_buf),
+ DMA_FROM_DEVICE);
+
if (nandc->tx_chan)
dma_release_channel(nandc->tx_chan);