From e8751a9387add3fb786828498352103b7188b296 Mon Sep 17 00:00:00 2001 From: Kuldeep Singh Date: Tue, 3 Aug 2021 14:32:57 +0530 Subject: [PATCH] spi: nxp-fspi: Add support for IP read only Add support for disabling AHB bus and read entire flash contents via IP bus only. Please note, this enables IP bus read using a quirk which can be enabled directly in device-type data or in existence of an errata where AHB bus may need to be disabled. Signed-off-by: Kuldeep Singh Acked-by: Jagan Teki --- drivers/spi/nxp_fspi.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/drivers/spi/nxp_fspi.c b/drivers/spi/nxp_fspi.c index bba7a330e0..7715ed9110 100644 --- a/drivers/spi/nxp_fspi.c +++ b/drivers/spi/nxp_fspi.c @@ -304,6 +304,9 @@ #define POLL_TOUT 5000 #define NXP_FSPI_MAX_CHIPSELECT 4 +/* Access flash memory using IP bus only */ +#define FSPI_QUIRK_USE_IP_ONLY BIT(0) + struct nxp_fspi_devtype_data { unsigned int rxfifo; unsigned int txfifo; @@ -338,6 +341,11 @@ struct nxp_fspi { const struct nxp_fspi_devtype_data *devtype_data; }; +static inline int needs_ip_only(struct nxp_fspi *f) +{ + return f->devtype_data->quirks & FSPI_QUIRK_USE_IP_ONLY; +} + /* * R/W functions for big- or little-endian registers: * The FSPI controller's endianness is independent of @@ -769,12 +777,14 @@ static int nxp_fspi_exec_op(struct spi_slave *slave, nxp_fspi_prepare_lut(f, op); /* - * If we have large chunks of data, we read them through the AHB bus - * by accessing the mapped memory. In all other cases we use - * IP commands to access the flash. + * If we have large chunks of data, we read them through the AHB bus by + * accessing the mapped memory. In all other cases we use IP commands + * to access the flash. Read via AHB bus may be corrupted due to + * existence of an errata and therefore discard AHB read in such cases. */ if (op->data.nbytes > (f->devtype_data->rxfifo - 4) && - op->data.dir == SPI_MEM_DATA_IN) { + op->data.dir == SPI_MEM_DATA_IN && + !needs_ip_only(f)) { nxp_fspi_read_ahb(f, op); } else { if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT) @@ -808,6 +818,12 @@ static int nxp_fspi_adjust_op_size(struct spi_slave *slave, op->data.nbytes = ALIGN_DOWN(op->data.nbytes, 8); } + /* Limit data bytes to RX FIFO in case of IP read only */ + if (needs_ip_only(f) && + op->data.dir == SPI_MEM_DATA_IN && + op->data.nbytes > f->devtype_data->rxfifo) + op->data.nbytes = f->devtype_data->rxfifo; + return 0; } -- 2.39.5