| Message ID | 20240125145007.748295-11-tudor.ambarus@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | spi: s3c64xx: winter cleanup and gs101 support | expand |
On Thu, Jan 25, 2024 at 8:50 AM Tudor Ambarus <tudor.ambarus@linaro.org> wrote: > > SPI_STATUSn.{RX, TX}_FIFO_LVL fields show the data level in the RX and > TX FIFOs. The IP supports FIFOs from 8 to 256 bytes, but apart from the > MODE_CFG.{RX, TX}_RDY_LVL fields that configure the {RX, TX} FIFO > trigger level in the interrupt mode, there's nothing in the registers > that configure the FIFOs depth. Is the responsibility of the SoC that > integrates the IP to dictate the FIFO depth and of the SPI driver to > make sure it doesn't bypass the FIFO length. > > {RX, TX}_FIFO_LVL was used to pass the FIFO length information based on > the IP configuration in the SoC. Its value was defined so that it > includes the entire FIFO length. For example, if one wanted to specify a > 64 FIFO length (0x40), it wold configure the FIFO level to 127 (0x7f). s/wodl/would/ > This is not only wrong, because it doesn't respect the IP's register > fields, it's also misleading. Use the full mask for the > SPI_STATUSn.{RX, TX}_FIFO_LVL fields. No change in functionality is > expected. > > Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> > --- > drivers/spi/spi-s3c64xx.c | 21 +++++++++++---------- > 1 file changed, 11 insertions(+), 10 deletions(-) > > diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c > index d046810da51f..b048e81e6207 100644 > --- a/drivers/spi/spi-s3c64xx.c > +++ b/drivers/spi/spi-s3c64xx.c > @@ -78,6 +78,8 @@ > #define S3C64XX_SPI_INT_RX_FIFORDY_EN BIT(1) > #define S3C64XX_SPI_INT_TX_FIFORDY_EN BIT(0) > > +#define S3C64XX_SPI_ST_RX_FIFO_LVL GENMASK(23, 15) What about s3c* architectures, where RX_LVL starts with bit #13, as can be seen from .rx_lvl_offset values in corresponding port_configs? Wouldn't this change break those? More generally, I don't understand why this patch is needed. Looks like it just changes the naming of the FIFO level accessing macros, making the code more bloated too. > +#define S3C64XX_SPI_ST_TX_FIFO_LVL GENMASK(14, 6) > #define S3C64XX_SPI_ST_RX_OVERRUN_ERR BIT(5) > #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR BIT(4) > #define S3C64XX_SPI_ST_TX_OVERRUN_ERR BIT(3) > @@ -108,9 +110,6 @@ > #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id]) > #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \ > (1 << (i)->port_conf->tx_st_done)) ? 1 : 0) > -#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i)) > -#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \ > - FIFO_LVL_MASK(i)) > #define FIFO_DEPTH(i) ((FIFO_LVL_MASK(i) >> 1) + 1) > > #define S3C64XX_SPI_POLLING_SIZE 32 > @@ -219,7 +218,7 @@ static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd) > loops = msecs_to_loops(1); > do { > val = readl(regs + S3C64XX_SPI_STATUS); > - } while (TX_FIFO_LVL(val, sdd) && loops--); > + } while (FIELD_GET(S3C64XX_SPI_ST_TX_FIFO_LVL, val) && loops--); > > if (loops == 0) > dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n"); > @@ -228,7 +227,7 @@ static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd) > loops = msecs_to_loops(1); > do { > val = readl(regs + S3C64XX_SPI_STATUS); > - if (RX_FIFO_LVL(val, sdd)) > + if (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, val)) > readl(regs + S3C64XX_SPI_RX_DATA); > else > break; > @@ -499,10 +498,11 @@ static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd, > > do { > status = readl(regs + S3C64XX_SPI_STATUS); > - } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val); > + } while (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status) < max_fifo && > + --val); > > /* return the actual received data length */ > - return RX_FIFO_LVL(status, sdd); > + return FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status); > } > > static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd, > @@ -533,7 +533,7 @@ static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd, > if (val && !xfer->rx_buf) { > val = msecs_to_loops(10); > status = readl(regs + S3C64XX_SPI_STATUS); > - while ((TX_FIFO_LVL(status, sdd) > + while ((FIELD_GET(S3C64XX_SPI_ST_TX_FIFO_LVL, status) > || !S3C64XX_SPI_ST_TX_DONE(status, sdd)) > && --val) { > cpu_relax(); > @@ -568,7 +568,7 @@ static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd, > > /* sleep during signal transfer time */ > status = readl(regs + S3C64XX_SPI_STATUS); > - if (RX_FIFO_LVL(status, sdd) < xfer->len) > + if (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status) < xfer->len) > usleep_range(time_us / 2, time_us); > > if (use_irq) { > @@ -580,7 +580,8 @@ static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd, > val = msecs_to_loops(ms); > do { > status = readl(regs + S3C64XX_SPI_STATUS); > - } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val); > + } while (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status) < xfer->len && > + --val); > > if (!val) > return -EIO; > -- > 2.43.0.429.g432eaa2c6b-goog >
On Thu, Jan 25, 2024 at 02:03:15PM -0600, Sam Protsenko wrote: > On Thu, Jan 25, 2024 at 8:50 AM Tudor Ambarus <tudor.ambarus@linaro.org> wrote: > > +#define S3C64XX_SPI_ST_RX_FIFO_LVL GENMASK(23, 15) > What about s3c* architectures, where RX_LVL starts with bit #13, as > can be seen from .rx_lvl_offset values in corresponding port_configs? > Wouldn't this change break those? I should point out that I have a s3c6410 board I care about.
On 1/25/24 20:03, Sam Protsenko wrote: > On Thu, Jan 25, 2024 at 8:50 AM Tudor Ambarus <tudor.ambarus@linaro.org> wrote: >> >> SPI_STATUSn.{RX, TX}_FIFO_LVL fields show the data level in the RX and >> TX FIFOs. The IP supports FIFOs from 8 to 256 bytes, but apart from the >> MODE_CFG.{RX, TX}_RDY_LVL fields that configure the {RX, TX} FIFO >> trigger level in the interrupt mode, there's nothing in the registers >> that configure the FIFOs depth. Is the responsibility of the SoC that >> integrates the IP to dictate the FIFO depth and of the SPI driver to >> make sure it doesn't bypass the FIFO length. >> >> {RX, TX}_FIFO_LVL was used to pass the FIFO length information based on >> the IP configuration in the SoC. Its value was defined so that it >> includes the entire FIFO length. For example, if one wanted to specify a >> 64 FIFO length (0x40), it wold configure the FIFO level to 127 (0x7f). > > s/wodl/would/ oh, yes, thanks > >> This is not only wrong, because it doesn't respect the IP's register >> fields, it's also misleading. Use the full mask for the >> SPI_STATUSn.{RX, TX}_FIFO_LVL fields. No change in functionality is >> expected. >> >> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> >> --- >> drivers/spi/spi-s3c64xx.c | 21 +++++++++++---------- >> 1 file changed, 11 insertions(+), 10 deletions(-) >> >> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c >> index d046810da51f..b048e81e6207 100644 >> --- a/drivers/spi/spi-s3c64xx.c >> +++ b/drivers/spi/spi-s3c64xx.c >> @@ -78,6 +78,8 @@ >> #define S3C64XX_SPI_INT_RX_FIFORDY_EN BIT(1) >> #define S3C64XX_SPI_INT_TX_FIFORDY_EN BIT(0) >> >> +#define S3C64XX_SPI_ST_RX_FIFO_LVL GENMASK(23, 15) > > What about s3c* architectures, where RX_LVL starts with bit #13, as > can be seen from .rx_lvl_offset values in corresponding port_configs? > Wouldn't this change break those? ah, wonderful catch, Sam. I break those indeed. > > More generally, I don't understand why this patch is needed. Looks I said in the commit message and subject that I'd like to use the full FIFO level mask rather than just a partial mask. On gs101 at least, that register field is on 9 bits, but as the code is now, we consider that register on 7 bits. For gs101 the FIFO size is always 64 bytes, thus indirectly the fifo_lvl_mask is always 0x7f. Unfortunately I'll drop this patch because I don't have access to all the SoC datasheets, thus I can't tell for sure if that register is always 9 bits wide. s3c2443 and s3c6410, which have the rx-lvl-offset set to 13, use just 0x7f masks. That's a pitty.
On 1/25/24 21:48, Mark Brown wrote: > On Thu, Jan 25, 2024 at 02:03:15PM -0600, Sam Protsenko wrote: >> On Thu, Jan 25, 2024 at 8:50 AM Tudor Ambarus <tudor.ambarus@linaro.org> wrote: > >>> +#define S3C64XX_SPI_ST_RX_FIFO_LVL GENMASK(23, 15) > >> What about s3c* architectures, where RX_LVL starts with bit #13, as >> can be seen from .rx_lvl_offset values in corresponding port_configs? >> Wouldn't this change break those? > > I should point out that I have a s3c6410 board I care about. Obviously, I don't want to break things, but it may happen as Sam pointed out. I'll be around to fix whatever I break. It's good that you have a s3c6410 board, maybe you can run a test on it after I send v3? Thanks!
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index d046810da51f..b048e81e6207 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c @@ -78,6 +78,8 @@ #define S3C64XX_SPI_INT_RX_FIFORDY_EN BIT(1) #define S3C64XX_SPI_INT_TX_FIFORDY_EN BIT(0) +#define S3C64XX_SPI_ST_RX_FIFO_LVL GENMASK(23, 15) +#define S3C64XX_SPI_ST_TX_FIFO_LVL GENMASK(14, 6) #define S3C64XX_SPI_ST_RX_OVERRUN_ERR BIT(5) #define S3C64XX_SPI_ST_RX_UNDERRUN_ERR BIT(4) #define S3C64XX_SPI_ST_TX_OVERRUN_ERR BIT(3) @@ -108,9 +110,6 @@ #define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id]) #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \ (1 << (i)->port_conf->tx_st_done)) ? 1 : 0) -#define TX_FIFO_LVL(v, i) (((v) >> 6) & FIFO_LVL_MASK(i)) -#define RX_FIFO_LVL(v, i) (((v) >> (i)->port_conf->rx_lvl_offset) & \ - FIFO_LVL_MASK(i)) #define FIFO_DEPTH(i) ((FIFO_LVL_MASK(i) >> 1) + 1) #define S3C64XX_SPI_POLLING_SIZE 32 @@ -219,7 +218,7 @@ static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd) loops = msecs_to_loops(1); do { val = readl(regs + S3C64XX_SPI_STATUS); - } while (TX_FIFO_LVL(val, sdd) && loops--); + } while (FIELD_GET(S3C64XX_SPI_ST_TX_FIFO_LVL, val) && loops--); if (loops == 0) dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n"); @@ -228,7 +227,7 @@ static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd) loops = msecs_to_loops(1); do { val = readl(regs + S3C64XX_SPI_STATUS); - if (RX_FIFO_LVL(val, sdd)) + if (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, val)) readl(regs + S3C64XX_SPI_RX_DATA); else break; @@ -499,10 +498,11 @@ static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd, do { status = readl(regs + S3C64XX_SPI_STATUS); - } while (RX_FIFO_LVL(status, sdd) < max_fifo && --val); + } while (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status) < max_fifo && + --val); /* return the actual received data length */ - return RX_FIFO_LVL(status, sdd); + return FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status); } static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd, @@ -533,7 +533,7 @@ static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd, if (val && !xfer->rx_buf) { val = msecs_to_loops(10); status = readl(regs + S3C64XX_SPI_STATUS); - while ((TX_FIFO_LVL(status, sdd) + while ((FIELD_GET(S3C64XX_SPI_ST_TX_FIFO_LVL, status) || !S3C64XX_SPI_ST_TX_DONE(status, sdd)) && --val) { cpu_relax(); @@ -568,7 +568,7 @@ static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd, /* sleep during signal transfer time */ status = readl(regs + S3C64XX_SPI_STATUS); - if (RX_FIFO_LVL(status, sdd) < xfer->len) + if (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status) < xfer->len) usleep_range(time_us / 2, time_us); if (use_irq) { @@ -580,7 +580,8 @@ static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd, val = msecs_to_loops(ms); do { status = readl(regs + S3C64XX_SPI_STATUS); - } while (RX_FIFO_LVL(status, sdd) < xfer->len && --val); + } while (FIELD_GET(S3C64XX_SPI_ST_RX_FIFO_LVL, status) < xfer->len && + --val); if (!val) return -EIO;
SPI_STATUSn.{RX, TX}_FIFO_LVL fields show the data level in the RX and TX FIFOs. The IP supports FIFOs from 8 to 256 bytes, but apart from the MODE_CFG.{RX, TX}_RDY_LVL fields that configure the {RX, TX} FIFO trigger level in the interrupt mode, there's nothing in the registers that configure the FIFOs depth. Is the responsibility of the SoC that integrates the IP to dictate the FIFO depth and of the SPI driver to make sure it doesn't bypass the FIFO length. {RX, TX}_FIFO_LVL was used to pass the FIFO length information based on the IP configuration in the SoC. Its value was defined so that it includes the entire FIFO length. For example, if one wanted to specify a 64 FIFO length (0x40), it wold configure the FIFO level to 127 (0x7f). This is not only wrong, because it doesn't respect the IP's register fields, it's also misleading. Use the full mask for the SPI_STATUSn.{RX, TX}_FIFO_LVL fields. No change in functionality is expected. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> --- drivers/spi/spi-s3c64xx.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-)