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>
This commit is contained in:
Jean Pihet 2020-01-14 13:41:24 +01:00 committed by Mark Brown
parent b8d40d7712
commit e97f491450
No known key found for this signature in database
GPG key ID: 24D68B725D5487D0

View file

@ -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,