From: Yunhui Cui <[email protected]> A-009282: QuadSPI: QuadSPI data pre-fetch can result in incorrect data Affects: QuadSPI Description: With AHB buffer prefetch enabled, the QuadSPI may return incorrect data on the AHB interface. The buffer pre-fetch is enabled if the fetch size as configured either in the LUT or in the BUFxCR register is greater than 8 bytes. Impact: Only 64 bit read allowed. Workaround: Keep the read data size to 64 bits (8 Bytes), which disables the prefetch on the AHB buffer, and prevents this issue from occurring.
Signed-off-by: Yunhui Cui <[email protected]> --- drivers/mtd/spi-nor/fsl-quadspi.c | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) diff --git a/drivers/mtd/spi-nor/fsl-quadspi.c b/drivers/mtd/spi-nor/fsl-quadspi.c index fea18b6..d9f3e50 100644 --- a/drivers/mtd/spi-nor/fsl-quadspi.c +++ b/drivers/mtd/spi-nor/fsl-quadspi.c @@ -752,19 +752,36 @@ static void fsl_qspi_init_abh_read(struct fsl_qspi *q) { void __iomem *base = q->iobase; int seqid; + const struct fsl_qspi_devtype_data *devtype_data = q->devtype_data; /* AHB configuration for access buffer 0/1/2 .*/ qspi_writel(q, QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF0CR); qspi_writel(q, QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF1CR); qspi_writel(q, QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF2CR); + /* - * Set ADATSZ with the maximum AHB buffer size to improve the - * read performance. + * Errata: A-009282: QuadSPI data prefetch may result in incorrect data + * Workaround: Keep the read data size to 64 bits (8 bytes). + * This disables the prefetch on the AHB buffer and + * prevents this issue from occurring. */ - qspi_writel(q, QUADSPI_BUF3CR_ALLMST_MASK | - ((q->devtype_data->ahb_buf_size / 8) - << QUADSPI_BUF3CR_ADATSZ_SHIFT), - base + QUADSPI_BUF3CR); + if (devtype_data->devtype == FSL_QUADSPI_LS2080A || + devtype_data->devtype == FSL_QUADSPI_LS1021A) { + + qspi_writel(q, QUADSPI_BUF3CR_ALLMST_MASK | + (1 << QUADSPI_BUF3CR_ADATSZ_SHIFT), + base + QUADSPI_BUF3CR); + + } else { + /* + * Set ADATSZ with the maximum AHB buffer size to improve the + * read performance. + */ + qspi_writel(q, QUADSPI_BUF3CR_ALLMST_MASK | + ((q->devtype_data->ahb_buf_size / 8) + << QUADSPI_BUF3CR_ADATSZ_SHIFT), + base + QUADSPI_BUF3CR); + } /* We only use the buffer3 */ qspi_writel(q, 0, base + QUADSPI_BUF0IND); -- 2.1.0.27.g96db324
