diff options
| author | Sai Krishna Potthuri <sai.krishna.potthuri@amd.com> | 2023-03-20 15:29:31 +0530 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2023-04-17 18:16:39 +0100 |
| commit | c0b53f4e545e4c6106aab553eb351138d46211cc (patch) | |
| tree | 13c7b6b29ecb99ebd4e66f0e76b92e792b395bca /drivers/spi/spi-cadence-quadspi.c | |
| parent | 22c8ce0aa274cea2ff538ffdf723053ecf77d78b (diff) | |
| download | lwn-c0b53f4e545e4c6106aab553eb351138d46211cc.tar.gz lwn-c0b53f4e545e4c6106aab553eb351138d46211cc.zip | |
spi: cadence-quadspi: Disable the SPI before reconfiguring
Observed random DMA timeout failures while doing back to back
transfers which involves switching the modes from DMA to NON-DMA.
This issue is observed while testing the OSPI+UBIFS file system test case
where rootfs is mounted from OSPI UBIFS partition.
To avoid this issue, disable the SPI before changing the configuration
from external DMA to NON-DMA and vice versa and reenable it after changing
the configuration.
As per the Cadence Octal SPI design specification, it is recommended to
disable the Octal-SPI enable bit before reconfiguring.
Signed-off-by: Sai Krishna Potthuri <sai.krishna.potthuri@amd.com>
Link: https://lore.kernel.org/r/20230320095931.2651714-3-sai.krishna.potthuri@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-cadence-quadspi.c')
| -rw-r--r-- | drivers/spi/spi-cadence-quadspi.c | 38 |
1 files changed, 23 insertions, 15 deletions
diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c index e281732aba91..d4a2b72985da 100644 --- a/drivers/spi/spi-cadence-quadspi.c +++ b/drivers/spi/spi-cadence-quadspi.c @@ -791,6 +791,21 @@ failrd: return ret; } +static void cqspi_controller_enable(struct cqspi_st *cqspi, bool enable) +{ + void __iomem *reg_base = cqspi->iobase; + unsigned int reg; + + reg = readl(reg_base + CQSPI_REG_CONFIG); + + if (enable) + reg |= CQSPI_REG_CONFIG_ENABLE_MASK; + else + reg &= ~CQSPI_REG_CONFIG_ENABLE_MASK; + + writel(reg, reg_base + CQSPI_REG_CONFIG); +} + static int cqspi_versal_indirect_read_dma(struct cqspi_flash_pdata *f_pdata, u_char *rxbuf, loff_t from_addr, size_t n_rx) @@ -815,10 +830,14 @@ static int cqspi_versal_indirect_read_dma(struct cqspi_flash_pdata *f_pdata, if (ret) return ret; + cqspi_controller_enable(cqspi, 0); + reg = readl(cqspi->iobase + CQSPI_REG_CONFIG); reg |= CQSPI_REG_CONFIG_DMA_MASK; writel(reg, cqspi->iobase + CQSPI_REG_CONFIG); + cqspi_controller_enable(cqspi, 1); + dma_addr = dma_map_single(dev, rxbuf, bytes_to_dma, DMA_FROM_DEVICE); if (dma_mapping_error(dev, dma_addr)) { dev_err(dev, "dma mapping failed\n"); @@ -876,10 +895,14 @@ static int cqspi_versal_indirect_read_dma(struct cqspi_flash_pdata *f_pdata, cqspi->iobase + CQSPI_REG_INDIRECTRD); dma_unmap_single(dev, dma_addr, bytes_to_dma, DMA_FROM_DEVICE); + cqspi_controller_enable(cqspi, 0); + reg = readl(cqspi->iobase + CQSPI_REG_CONFIG); reg &= ~CQSPI_REG_CONFIG_DMA_MASK; writel(reg, cqspi->iobase + CQSPI_REG_CONFIG); + cqspi_controller_enable(cqspi, 1); + ret = zynqmp_pm_ospi_mux_select(cqspi->pd_dev_id, PM_OSPI_MUX_SEL_LINEAR); if (ret) @@ -1182,21 +1205,6 @@ static void cqspi_readdata_capture(struct cqspi_st *cqspi, writel(reg, reg_base + CQSPI_REG_READCAPTURE); } -static void cqspi_controller_enable(struct cqspi_st *cqspi, bool enable) -{ - void __iomem *reg_base = cqspi->iobase; - unsigned int reg; - - reg = readl(reg_base + CQSPI_REG_CONFIG); - - if (enable) - reg |= CQSPI_REG_CONFIG_ENABLE_MASK; - else - reg &= ~CQSPI_REG_CONFIG_ENABLE_MASK; - - writel(reg, reg_base + CQSPI_REG_CONFIG); -} - static void cqspi_configure(struct cqspi_flash_pdata *f_pdata, unsigned long sclk) { |