Hi Vignesh,
Thank you for the review comments.
On 16/10/2019 4:40 PM, Vignesh Raghavendra wrote:
On 09/09/19 4:17 PM, Ramuthevar,Vadivel MuruganX wrote:
From: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@xxxxxxxxxxxxxxx>
On Intel's Lightning Mountain(LGM) SoC QSPI controller do not auto-poll.
This patch introduces to properly disable the auto-polling feature to
This patch disables auto polling when direct access mode is disabled
which should be noted in the commit message.
will add it.
improve the performance of cadence-quadspi.
How does this improve performance of cadence-quadspi? I would expect HW
auto-polling to be faster than SW polling.
During the bring-up time observed this, once again verify it on my setup.
Agreed, you are correct HW auto-polling is faster than SW polling.
Signed-off-by: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@xxxxxxxxxxxxxxx>
---
drivers/mtd/spi-nor/cadence-quadspi.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c
index 73b9fbd1508a..60998eaad1cc 100644
--- a/drivers/mtd/spi-nor/cadence-quadspi.c
+++ b/drivers/mtd/spi-nor/cadence-quadspi.c
@@ -135,6 +135,8 @@ struct cqspi_driver_platdata {
#define CQSPI_REG_RD_INSTR_TYPE_DATA_MASK 0x3
#define CQSPI_REG_RD_INSTR_DUMMY_MASK 0x1F
+#define CQSPI_REG_WR_COMPLETION_CTRL 0x38
+#define CQSPI_REG_WR_COMPLETION_DISABLE_AUTO_POLL BIT(14)
#define CQSPI_REG_WR_INSTR 0x08
#define CQSPI_REG_WR_INSTR_OPCODE_LSB 0
#define CQSPI_REG_WR_INSTR_TYPE_ADDR_LSB 12
@@ -471,6 +473,18 @@ static int cqspi_command_write_addr(struct spi_nor *nor,
return cqspi_exec_flash_cmd(cqspi, reg);
}
+static int cqspi_disable_auto_poll(struct cqspi_st *cqspi)
+{
+ void __iomem *reg_base = cqspi->iobase;
+ unsigned int reg;
+
+ reg = readl(reg_base + CQSPI_REG_WR_COMPLETION_CTRL);
+ reg |= CQSPI_REG_WR_COMPLETION_DISABLE_AUTO_POLL;
+ writel(reg, reg_base + CQSPI_REG_WR_COMPLETION_CTRL);
+
+ return 0;
+}
+
static int cqspi_read_setup(struct spi_nor *nor)
{
struct cqspi_flash_pdata *f_pdata = nor->priv;
@@ -508,6 +522,11 @@ static int cqspi_read_setup(struct spi_nor *nor)
reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK;
reg |= (nor->addr_width - 1);
writel(reg, reg_base + CQSPI_REG_SIZE);
+
+ /* Disable auto-polling */
+ if (!f_pdata->use_direct_mode)
+ cqspi_disable_auto_poll(cqspi);
+
return 0;
}
Hmmm.. There is no need to disable polling for every read/write
operation. It should be enough to do it once in cqspi_controller_init()
sure, move to cqspi_controller_init() .
---
Regards
Vadivel
@@ -627,6 +646,11 @@ static int cqspi_write_setup(struct spi_nor *nor)
reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK;
reg |= (nor->addr_width - 1);
writel(reg, reg_base + CQSPI_REG_SIZE);
+
+ /* Disable auto-polling */
+ if (!f_pdata->use_direct_mode)
+ cqspi_disable_auto_poll(cqspi);
+
return 0;
}
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