diff options
author | Jean Pihet <jean.pihet@newoldbits.com> | 2020-01-14 13:41:24 +0100 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2020-01-14 15:25:46 +0000 |
commit | e97f491450805fe6cbfd482b97b5427b21dec575 (patch) | |
tree | 27b45d080c20d63d4e7c601b15520350a66c79e9 /drivers/spi | |
parent | b8d40d7712f10475effc4552eda96b9d44822cfb (diff) |
spi: spi-ti-qspi: support large flash devices
The TI QSPI IP has limitations:
- the MMIO region is 64MB in size
- in non-MMIO mode, the transfer can handle 4096 words max.
Add support for bigger devices.
Use MMIO and DMA transfers below the 64MB boundary, use
software generated transfers above.
Signed-off-by: Jean Pihet <jean.pihet@newoldbits.com>
Cc: Ryan Barnett <ryan.barnett@rockwellcollins.com>
Cc: Conrad Ratschan <conrad.ratschan@rockwellcollins.com>
Cc: Arnout Vandecappelle <arnout.vandecappelle@essensium.com>
Link: https://lore.kernel.org/r/20200114124125.361429-2-jean.pihet@newoldbits.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-ti-qspi.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c index ad2942b3d0a9..0334e2926998 100644 --- a/drivers/spi/spi-ti-qspi.c +++ b/drivers/spi/spi-ti-qspi.c @@ -525,6 +525,35 @@ static void ti_qspi_setup_mmap_read(struct spi_device *spi, u8 opcode, QSPI_SPI_SETUP_REG(spi->chip_select)); } +static int ti_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op) +{ + struct ti_qspi *qspi = spi_controller_get_devdata(mem->spi->master); + size_t max_len; + + if (op->data.dir == SPI_MEM_DATA_IN) { + if (op->addr.val < qspi->mmap_size) { + /* Limit MMIO to the mmaped region */ + if (op->addr.val + op->data.nbytes > qspi->mmap_size) { + max_len = qspi->mmap_size - op->addr.val; + op->data.nbytes = min((size_t) op->data.nbytes, + max_len); + } + } else { + /* + * Use fallback mode (SW generated transfers) above the + * mmaped region. + * Adjust size to comply with the QSPI max frame length. + */ + max_len = QSPI_FRAME; + max_len -= 1 + op->addr.nbytes + op->dummy.nbytes; + op->data.nbytes = min((size_t) op->data.nbytes, + max_len); + } + } + + return 0; +} + static int ti_qspi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op) { @@ -575,6 +604,7 @@ static int ti_qspi_exec_mem_op(struct spi_mem *mem, static const struct spi_controller_mem_ops ti_qspi_mem_ops = { .exec_op = ti_qspi_exec_mem_op, + .adjust_op_size = ti_qspi_adjust_op_size, }; static int ti_qspi_start_transfer_one(struct spi_master *master, |