As per 66AK2G02 TRM[1] SPRUHY8F section 11.15.5.3 Indirect Access Controller programming sequence, a delay equal to couple of QSPI master clock(~5ns) is required after setting CQSPI_REG_INDIRECTWR_START bit and writing data to the flash. Introduce a quirk flag CQSPI_NEEDS_WR_DELAY to handle this and set this flag for TI 66AK2G SoC. [1]http://www.ti.com/lit/ug/spruhy8f/spruhy8f.pdf Signed-off-by: Vignesh R <vigneshr@xxxxxx> --- v3: Fix build warnings reported by kbuild test bot. drivers/mtd/spi-nor/cadence-quadspi.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c index 53c7d8e0327a..5cd5d6f7303f 100644 --- a/drivers/mtd/spi-nor/cadence-quadspi.c +++ b/drivers/mtd/spi-nor/cadence-quadspi.c @@ -38,6 +38,9 @@ #define CQSPI_NAME "cadence-qspi" #define CQSPI_MAX_CHIPSELECT 16 +/* Quirks */ +#define CQSPI_NEEDS_WR_DELAY BIT(0) + struct cqspi_st; struct cqspi_flash_pdata { @@ -76,6 +79,7 @@ struct cqspi_st { u32 fifo_depth; u32 fifo_width; u32 trigger_address; + u32 wr_delay; struct cqspi_flash_pdata f_pdata[CQSPI_MAX_CHIPSELECT]; }; @@ -608,6 +612,15 @@ static int cqspi_indirect_write_execute(struct spi_nor *nor, reinit_completion(&cqspi->transfer_complete); writel(CQSPI_REG_INDIRECTWR_START_MASK, reg_base + CQSPI_REG_INDIRECTWR); + /* + * As per 66AK2G02 TRM SPRUHY8F section 11.15.5.3 Indirect Access + * Controller programming sequence, couple of cycles of + * QSPI_REF_CLK delay is required for the above bit to + * be internally synchronized by the QSPI module. Provide 5 + * cycles of delay. + */ + if (cqspi->wr_delay) + ndelay(cqspi->wr_delay); while (remaining > 0) { write_bytes = remaining > page_size ? page_size : remaining; @@ -1156,6 +1169,7 @@ static int cqspi_probe(struct platform_device *pdev) struct cqspi_st *cqspi; struct resource *res; struct resource *res_ahb; + unsigned long data; int ret; int irq; @@ -1213,6 +1227,10 @@ static int cqspi_probe(struct platform_device *pdev) } cqspi->master_ref_clk_hz = clk_get_rate(cqspi->clk); + data = (unsigned long)of_device_get_match_data(dev); + if (data & CQSPI_NEEDS_WR_DELAY) + cqspi->wr_delay = 5 * DIV_ROUND_UP(NSEC_PER_SEC, + cqspi->master_ref_clk_hz); ret = devm_request_irq(dev, irq, cqspi_irq_handler, 0, pdev->name, cqspi); @@ -1284,7 +1302,14 @@ static const struct dev_pm_ops cqspi__dev_pm_ops = { #endif static const struct of_device_id cqspi_dt_ids[] = { - {.compatible = "cdns,qspi-nor",}, + { + .compatible = "cdns,qspi-nor", + .data = (void *)0, + }, + { + .compatible = "ti,k2g-qspi", + .data = (void *)CQSPI_NEEDS_WR_DELAY, + }, { /* end of table */ } }; -- 2.14.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
