[PATCH v1] spi: dw: add check for Rx FIFO overflow
If even one byte is lost due to Rx FIFO overflow then we will never exit the read loop. Because the (priv->rx != priv->rx_end) condition will be always true.
Let's check if Rx FIFO overflow occurred and exit the read loop in this case.
Signed-off-by: Maksim Kiselev bigunclemax@gmail.com --- drivers/spi/designware_spi.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c index 1c7d0ca310..0f443bff8e 100644 --- a/drivers/spi/designware_spi.c +++ b/drivers/spi/designware_spi.c @@ -111,6 +111,15 @@ #define SR_TX_ERR BIT(5) #define SR_DCOL BIT(6)
+/* Bit fields in ISR, IMR, RISR, 7 bits */ +#define DW_SPI_INT_MASK GENMASK(5, 0) +#define DW_SPI_INT_TXEI BIT(0) +#define DW_SPI_INT_TXOI BIT(1) +#define DW_SPI_INT_RXUI BIT(2) +#define DW_SPI_INT_RXOI BIT(3) +#define DW_SPI_INT_RXFI BIT(4) +#define DW_SPI_INT_MSTI BIT(5) + #define RX_TIMEOUT 1000 /* timeout in ms */
struct dw_spi_plat { @@ -588,7 +597,7 @@ static int dw_spi_exec_op(struct spi_slave *slave, const struct spi_mem_op *op) struct dw_spi_priv *priv = dev_get_priv(bus); u8 op_len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes; u8 op_buf[op_len]; - u32 cr0; + u32 cr0, sts;
if (read) priv->tmode = CTRLR0_TMOD_EPROMREAD; @@ -632,12 +641,21 @@ static int dw_spi_exec_op(struct spi_slave *slave, const struct spi_mem_op *op) * them to fail because we are not reading/writing the fifo fast enough. */ if (read) { - priv->rx = op->data.buf.in; + void *prev_rx = priv->rx = op->data.buf.in; priv->rx_end = priv->rx + op->data.nbytes;
dw_write(priv, DW_SPI_SER, 1 << spi_chip_select(slave->dev)); - while (priv->rx != priv->rx_end) + while (priv->rx != priv->rx_end) { dw_reader(priv); + if (prev_rx == priv->rx) { + sts = dw_read(priv, DW_SPI_RISR); + if (sts & DW_SPI_INT_RXOI) { + dev_err(bus, "FIFO overflow on Rx\n"); + return -EIO; + } + } + prev_rx = priv->rx; + } } else { u32 val;
On Tue, Oct 17, 2023 at 12:35 PM Maksim Kiselev bigunclemax@gmail.com wrote:
If even one byte is lost due to Rx FIFO overflow then we will never exit the read loop. Because the (priv->rx != priv->rx_end) condition will be always true.
Let's check if Rx FIFO overflow occurred and exit the read loop in this case.
Signed-off-by: Maksim Kiselev bigunclemax@gmail.com
drivers/spi/designware_spi.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c index 1c7d0ca310..0f443bff8e 100644 --- a/drivers/spi/designware_spi.c +++ b/drivers/spi/designware_spi.c @@ -111,6 +111,15 @@ #define SR_TX_ERR BIT(5) #define SR_DCOL BIT(6)
+/* Bit fields in ISR, IMR, RISR, 7 bits */ +#define DW_SPI_INT_MASK GENMASK(5, 0) +#define DW_SPI_INT_TXEI BIT(0) +#define DW_SPI_INT_TXOI BIT(1) +#define DW_SPI_INT_RXUI BIT(2) +#define DW_SPI_INT_RXOI BIT(3) +#define DW_SPI_INT_RXFI BIT(4) +#define DW_SPI_INT_MSTI BIT(5)
Why do we need unused macros?
Jagan.
Hello Jagan,
пн, 18 дек. 2023 г. в 14:28, Jagan Teki jagan@amarulasolutions.com:
On Tue, Oct 17, 2023 at 12:35 PM Maksim Kiselev bigunclemax@gmail.com wrote:
If even one byte is lost due to Rx FIFO overflow then we will never exit the read loop. Because the (priv->rx != priv->rx_end) condition will be always true.
Let's check if Rx FIFO overflow occurred and exit the read loop in this case.
Signed-off-by: Maksim Kiselev bigunclemax@gmail.com
drivers/spi/designware_spi.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c index 1c7d0ca310..0f443bff8e 100644 --- a/drivers/spi/designware_spi.c +++ b/drivers/spi/designware_spi.c @@ -111,6 +111,15 @@ #define SR_TX_ERR BIT(5) #define SR_DCOL BIT(6)
+/* Bit fields in ISR, IMR, RISR, 7 bits */ +#define DW_SPI_INT_MASK GENMASK(5, 0) +#define DW_SPI_INT_TXEI BIT(0) +#define DW_SPI_INT_TXOI BIT(1) +#define DW_SPI_INT_RXUI BIT(2) +#define DW_SPI_INT_RXOI BIT(3) +#define DW_SPI_INT_RXFI BIT(4) +#define DW_SPI_INT_MSTI BIT(5)
Why do we need unused macros?
Actually DW_SPI_INT_RXOI is used. As for the other bits in DW_SPI_RISR, I decided to add them all to match a Linux driver.
We already have a lot of unused macro in this driver (ex. definitions for bits in CTRLR0_FRF, CTRLR0_MODE regs and so on).
So, what's a problem with adding the DW_SPI_RISR bits?
Cheers, Maksim
Jagan.
On Mon, Dec 18, 2023 at 11:01 PM Maxim Kiselev bigunclemax@gmail.com wrote:
Hello Jagan,
пн, 18 дек. 2023 г. в 14:28, Jagan Teki jagan@amarulasolutions.com:
On Tue, Oct 17, 2023 at 12:35 PM Maksim Kiselev bigunclemax@gmail.com wrote:
If even one byte is lost due to Rx FIFO overflow then we will never exit the read loop. Because the (priv->rx != priv->rx_end) condition will be always true.
Let's check if Rx FIFO overflow occurred and exit the read loop in this case.
Signed-off-by: Maksim Kiselev bigunclemax@gmail.com
drivers/spi/designware_spi.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c index 1c7d0ca310..0f443bff8e 100644 --- a/drivers/spi/designware_spi.c +++ b/drivers/spi/designware_spi.c @@ -111,6 +111,15 @@ #define SR_TX_ERR BIT(5) #define SR_DCOL BIT(6)
+/* Bit fields in ISR, IMR, RISR, 7 bits */ +#define DW_SPI_INT_MASK GENMASK(5, 0) +#define DW_SPI_INT_TXEI BIT(0) +#define DW_SPI_INT_TXOI BIT(1) +#define DW_SPI_INT_RXUI BIT(2) +#define DW_SPI_INT_RXOI BIT(3) +#define DW_SPI_INT_RXFI BIT(4) +#define DW_SPI_INT_MSTI BIT(5)
Why do we need unused macros?
Actually DW_SPI_INT_RXOI is used. As for the other bits in DW_SPI_RISR, I decided to add them all to match a Linux driver.
We already have a lot of unused macro in this driver (ex. definitions for bits in CTRLR0_FRF, CTRLR0_MODE regs and so on).
So, what's a problem with adding the DW_SPI_RISR bits?
I'm not fond of unused change in the particular patch, better to send the updated one with used bits.
Jagan.
participants (3)
-
Jagan Teki -
Maksim Kiselev -
Maxim Kiselev