Re: [PATCH 07/14] qcom: mtd: nand: support for passing flags in transfer functions

From: Archit Taneja
Date: Tue Jul 04 2017 - 02:49:32 EST




On 06/29/2017 12:45 PM, Abhishek Sahu wrote:
The BAM has multiple flags to control the transfer. This patch
adds flags parameter in register and data transfer functions and
modifies all these function call with appropriate flags.

Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx>
---
drivers/mtd/nand/qcom_nandc.c | 114 ++++++++++++++++++++++++------------------
1 file changed, 65 insertions(+), 49 deletions(-)

diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c
index 7042a65..65c9059 100644
--- a/drivers/mtd/nand/qcom_nandc.c
+++ b/drivers/mtd/nand/qcom_nandc.c
@@ -170,6 +170,14 @@
#define ECC_BCH_4BIT BIT(2)
#define ECC_BCH_8BIT BIT(3)
+/* Flags used for BAM DMA desc preparation*/
+/* Don't set the EOT in current tx sgl */
+#define NAND_BAM_NO_EOT (0x0001)
+/* Set the NWD flag in current sgl */
+#define NAND_BAM_NWD (0x0002)
+/* Finish writing in the current sgl and start writing in another sgl */
+#define NAND_BAM_NEXT_SGL (0x0004)
+
#define QPIC_PER_CW_MAX_CMD_ELEMENTS (32)
#define QPIC_PER_CW_MAX_CMD_SGL (32)
#define QPIC_PER_CW_MAX_DATA_SGL (8)
@@ -712,7 +720,7 @@ static int prep_dma_desc(struct qcom_nand_controller *nandc, bool read,
* @num_regs: number of registers to read
*/
static int read_reg_dma(struct qcom_nand_controller *nandc, int first,
- int num_regs)
+ int num_regs, unsigned int flags)
{
bool flow_control = false;
void *vaddr;
@@ -736,7 +744,7 @@ static int read_reg_dma(struct qcom_nand_controller *nandc, int first,
* @num_regs: number of registers to write
*/
static int write_reg_dma(struct qcom_nand_controller *nandc, int first,
- int num_regs)
+ int num_regs, unsigned int flags)

Adding flags to read_reg_dma and write_reg_dma is making things a bit messy. I can't
think of a better way to share the code either, though.

One thing we could consider doing is something like below. I don't know if it would
make things more legible.

union nand_dma_props {
bool adm_flow_control;
unsigned int bam_flags;
};

config_cw_read()
{
union nand_dma_props dma_props;
...
...

if (is_bam)
dma_props.bam_flags = NAND_BAM_NWD;
else
dma_props.adm_flow_control = false;

write_reg_dma(nandc, NAND_EXEC_CMD, 1, &dma_props);
...
...
}

Thanks,
Archit

{
bool flow_control = false;
struct nandc_regs *regs = nandc->regs;
@@ -748,6 +756,9 @@ static int write_reg_dma(struct qcom_nand_controller *nandc, int first,
if (first == NAND_FLASH_CMD)
flow_control = true;
+ if (first == NAND_EXEC_CMD)
+ flags |= NAND_BAM_NWD;
+
if (first == NAND_DEV_CMD1_RESTORE)
first = NAND_DEV_CMD1;
@@ -768,7 +779,7 @@ static int write_reg_dma(struct qcom_nand_controller *nandc, int first,
* @size: DMA transaction size in bytes
*/
static int read_data_dma(struct qcom_nand_controller *nandc, int reg_off,
- const u8 *vaddr, int size)
+ const u8 *vaddr, int size, unsigned int flags)
{
return prep_dma_desc(nandc, true, reg_off, vaddr, size, false);
}
@@ -782,7 +793,7 @@ static int read_data_dma(struct qcom_nand_controller *nandc, int reg_off,
* @size: DMA transaction size in bytes
*/
static int write_data_dma(struct qcom_nand_controller *nandc, int reg_off,
- const u8 *vaddr, int size)
+ const u8 *vaddr, int size, unsigned int flags)
{
return prep_dma_desc(nandc, false, reg_off, vaddr, size, false);
}
@@ -793,14 +804,16 @@ static int write_data_dma(struct qcom_nand_controller *nandc, int reg_off,
*/
static void config_cw_read(struct qcom_nand_controller *nandc)
{
- write_reg_dma(nandc, NAND_FLASH_CMD, 3);
- write_reg_dma(nandc, NAND_DEV0_CFG0, 3);
- write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1);
+ write_reg_dma(nandc, NAND_FLASH_CMD, 3, 0);
+ write_reg_dma(nandc, NAND_DEV0_CFG0, 3, 0);
+ write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1, 0);
- write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1,
+ NAND_BAM_NWD | NAND_BAM_NEXT_SGL);
- read_reg_dma(nandc, NAND_FLASH_STATUS, 2);
- read_reg_dma(nandc, NAND_ERASED_CW_DETECT_STATUS, 1);
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 2, 0);
+ read_reg_dma(nandc, NAND_ERASED_CW_DETECT_STATUS, 1,
+ NAND_BAM_NEXT_SGL);
}
/*
@@ -809,19 +822,20 @@ static void config_cw_read(struct qcom_nand_controller *nandc)
*/
static void config_cw_write_pre(struct qcom_nand_controller *nandc)
{
- write_reg_dma(nandc, NAND_FLASH_CMD, 3);
- write_reg_dma(nandc, NAND_DEV0_CFG0, 3);
- write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1);
+ write_reg_dma(nandc, NAND_FLASH_CMD, 3, 0);
+ write_reg_dma(nandc, NAND_DEV0_CFG0, 3, 0);
+ write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1,
+ NAND_BAM_NEXT_SGL);
}
static void config_cw_write_post(struct qcom_nand_controller *nandc)
{
- write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
- read_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
- write_reg_dma(nandc, NAND_FLASH_STATUS, 1);
- write_reg_dma(nandc, NAND_READ_STATUS, 1);
+ write_reg_dma(nandc, NAND_FLASH_STATUS, 1, 0);
+ write_reg_dma(nandc, NAND_READ_STATUS, 1, NAND_BAM_NEXT_SGL);
}
/*
@@ -869,8 +883,8 @@ static int nandc_param(struct qcom_nand_host *host)
nandc_set_reg(nandc, NAND_DEV_CMD1_RESTORE, nandc->cmd1);
nandc_set_reg(nandc, NAND_DEV_CMD_VLD_RESTORE, nandc->vld);
- write_reg_dma(nandc, NAND_DEV_CMD_VLD, 1);
- write_reg_dma(nandc, NAND_DEV_CMD1, 1);
+ write_reg_dma(nandc, NAND_DEV_CMD_VLD, 1, 0);
+ write_reg_dma(nandc, NAND_DEV_CMD1, 1, NAND_BAM_NEXT_SGL);
nandc->buf_count = 512;
memset(nandc->data_buffer, 0xff, nandc->buf_count);
@@ -878,11 +892,11 @@ static int nandc_param(struct qcom_nand_host *host)
config_cw_read(nandc);
read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer,
- nandc->buf_count);
+ nandc->buf_count, 0);
/* restore CMD1 and VLD regs */
- write_reg_dma(nandc, NAND_DEV_CMD1_RESTORE, 1);
- write_reg_dma(nandc, NAND_DEV_CMD_VLD_RESTORE, 1);
+ write_reg_dma(nandc, NAND_DEV_CMD1_RESTORE, 1, 0);
+ write_reg_dma(nandc, NAND_DEV_CMD_VLD_RESTORE, 1, NAND_BAM_NEXT_SGL);
return 0;
}
@@ -904,14 +918,14 @@ static int erase_block(struct qcom_nand_host *host, int page_addr)
nandc_set_reg(nandc, NAND_FLASH_STATUS, host->clrflashstatus);
nandc_set_reg(nandc, NAND_READ_STATUS, host->clrreadstatus);
- write_reg_dma(nandc, NAND_FLASH_CMD, 3);
- write_reg_dma(nandc, NAND_DEV0_CFG0, 2);
- write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+ write_reg_dma(nandc, NAND_FLASH_CMD, 3, NAND_BAM_NEXT_SGL);
+ write_reg_dma(nandc, NAND_DEV0_CFG0, 2, NAND_BAM_NEXT_SGL);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
- read_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
- write_reg_dma(nandc, NAND_FLASH_STATUS, 1);
- write_reg_dma(nandc, NAND_READ_STATUS, 1);
+ write_reg_dma(nandc, NAND_FLASH_STATUS, 1, 0);
+ write_reg_dma(nandc, NAND_READ_STATUS, 1, NAND_BAM_NEXT_SGL);
return 0;
}
@@ -931,10 +945,10 @@ static int read_id(struct qcom_nand_host *host, int column)
nandc_set_reg(nandc, NAND_FLASH_CHIP_SELECT, DM_EN);
nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
- write_reg_dma(nandc, NAND_FLASH_CMD, 4);
- write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+ write_reg_dma(nandc, NAND_FLASH_CMD, 4, NAND_BAM_NEXT_SGL);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
- read_reg_dma(nandc, NAND_READ_ID, 1);
+ read_reg_dma(nandc, NAND_READ_ID, 1, NAND_BAM_NEXT_SGL);
return 0;
}
@@ -948,10 +962,10 @@ static int reset(struct qcom_nand_host *host)
nandc_set_reg(nandc, NAND_FLASH_CMD, RESET_DEVICE);
nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
- write_reg_dma(nandc, NAND_FLASH_CMD, 1);
- write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+ write_reg_dma(nandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
- read_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
return 0;
}
@@ -1344,7 +1358,7 @@ static int read_page_ecc(struct qcom_nand_host *host, u8 *data_buf,
if (data_buf)
read_data_dma(nandc, FLASH_BUF_ACC, data_buf,
- data_size);
+ data_size, 0);
/*
* when ecc is enabled, the controller doesn't read the real
@@ -1360,7 +1374,7 @@ static int read_page_ecc(struct qcom_nand_host *host, u8 *data_buf,
*oob_buf++ = 0xff;
read_data_dma(nandc, FLASH_BUF_ACC + data_size,
- oob_buf, oob_size);
+ oob_buf, oob_size, 0);
}
if (data_buf)
@@ -1402,7 +1416,7 @@ static int copy_last_cw(struct qcom_nand_host *host, int page)
config_cw_read(nandc);
- read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, size);
+ read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, size, 0);
ret = submit_descs(nandc);
if (ret)
@@ -1470,19 +1484,19 @@ static int qcom_nandc_read_page_raw(struct mtd_info *mtd,
config_cw_read(nandc);
- read_data_dma(nandc, reg_off, data_buf, data_size1);
+ read_data_dma(nandc, reg_off, data_buf, data_size1, 0);
reg_off += data_size1;
data_buf += data_size1;
- read_data_dma(nandc, reg_off, oob_buf, oob_size1);
+ read_data_dma(nandc, reg_off, oob_buf, oob_size1, 0);
reg_off += oob_size1;
oob_buf += oob_size1;
- read_data_dma(nandc, reg_off, data_buf, data_size2);
+ read_data_dma(nandc, reg_off, data_buf, data_size2, 0);
reg_off += data_size2;
data_buf += data_size2;
- read_data_dma(nandc, reg_off, oob_buf, oob_size2);
+ read_data_dma(nandc, reg_off, oob_buf, oob_size2, 0);
oob_buf += oob_size2;
}
@@ -1549,7 +1563,8 @@ static int qcom_nandc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
config_cw_write_pre(nandc);
- write_data_dma(nandc, FLASH_BUF_ACC, data_buf, data_size);
+ write_data_dma(nandc, FLASH_BUF_ACC, data_buf, data_size,
+ i == (ecc->steps - 1) ? NAND_BAM_NO_EOT : 0);
/*
* when ECC is enabled, we don't really need to write anything
@@ -1562,7 +1577,7 @@ static int qcom_nandc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
oob_buf += host->bbm_size;
write_data_dma(nandc, FLASH_BUF_ACC + data_size,
- oob_buf, oob_size);
+ oob_buf, oob_size, 0);
}
config_cw_write_post(nandc);
@@ -1618,19 +1633,19 @@ static int qcom_nandc_write_page_raw(struct mtd_info *mtd,
config_cw_write_pre(nandc);
- write_data_dma(nandc, reg_off, data_buf, data_size1);
+ write_data_dma(nandc, reg_off, data_buf, data_size1, 0);
reg_off += data_size1;
data_buf += data_size1;
- write_data_dma(nandc, reg_off, oob_buf, oob_size1);
+ write_data_dma(nandc, reg_off, oob_buf, oob_size1, 0);
reg_off += oob_size1;
oob_buf += oob_size1;
- write_data_dma(nandc, reg_off, data_buf, data_size2);
+ write_data_dma(nandc, reg_off, data_buf, data_size2, 0);
reg_off += data_size2;
data_buf += data_size2;
- write_data_dma(nandc, reg_off, oob_buf, oob_size2);
+ write_data_dma(nandc, reg_off, oob_buf, oob_size2, 0);
oob_buf += oob_size2;
config_cw_write_post(nandc);
@@ -1685,7 +1700,7 @@ static int qcom_nandc_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
config_cw_write_pre(nandc);
write_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer,
- data_size + oob_size);
+ data_size + oob_size, 0);
config_cw_write_post(nandc);
ret = submit_descs(nandc);
@@ -1769,7 +1784,8 @@ static int qcom_nandc_block_markbad(struct mtd_info *mtd, loff_t ofs)
update_rw_regs(host, 1, false);
config_cw_write_pre(nandc);
- write_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, host->cw_size);
+ write_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer,
+ host->cw_size, 0);
config_cw_write_post(nandc);
ret = submit_descs(nandc);


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