spi: 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 <kuldeep.singh@nxp.com>
Link: https://lore.kernel.org/r/20210302124936.1972546-2-kuldeep.singh@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Kuldeep Singh 2021-03-02 18:19:33 +05:30 committed by Mark Brown
parent 87d62d8fa6
commit 31e92cbfb9
No known key found for this signature in database
GPG key ID: 24D68B725D5487D0

View file

@ -311,6 +311,9 @@
#define NXP_FSPI_MAX_CHIPSELECT 4
#define NXP_FSPI_MIN_IOMAP SZ_4M
/* 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;
@ -359,6 +362,11 @@ struct nxp_fspi {
int selected;
};
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
@ -553,8 +561,8 @@ static void nxp_fspi_prepare_lut(struct nxp_fspi *f,
for (i = 0; i < ARRAY_SIZE(lutval); i++)
fspi_writel(f, lutval[i], base + FSPI_LUT_REG(i));
dev_dbg(f->dev, "CMD[%x] lutval[0:%x \t 1:%x \t 2:%x \t 3:%x]\n",
op->cmd.opcode, lutval[0], lutval[1], lutval[2], lutval[3]);
dev_dbg(f->dev, "CMD[%x] lutval[0:%x \t 1:%x \t 2:%x \t 3:%x], size: 0x%08x\n",
op->cmd.opcode, lutval[0], lutval[1], lutval[2], lutval[3], op->data.nbytes);
/* lock LUT */
fspi_writel(f, FSPI_LUTKEY_VALUE, f->iobase + FSPI_LUTKEY);
@ -852,12 +860,14 @@ static int nxp_fspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
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)) {
err = nxp_fspi_read_ahb(f, op);
} else {
if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT)
@ -888,6 +898,12 @@ static int nxp_fspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
op->data.nbytes = ALIGN_DOWN(op->data.nbytes, 8);
}
/* Limit data bytes to RX FIFO in case of IP read only */
if (op->data.dir == SPI_MEM_DATA_IN &&
needs_ip_only(f) &&
op->data.nbytes > f->devtype_data->rxfifo)
op->data.nbytes = f->devtype_data->rxfifo;
return 0;
}