memory: renesas-rpc-if: Fix HF/OSPI data transfer in Manual Mode

HyperFlash devices fail to probe:

    rpc-if-hyperflash rpc-if-hyperflash: probing of hyperbus device failed

In HyperFlash or Octal-SPI Flash mode, the Transfer Data Enable bits
(SPIDE) in the Manual Mode Enable Setting Register (SMENR) are derived
from half of the transfer size, cfr. the rpcif_bits_set() helper
function.  However, rpcif_reg_{read,write}() does not take the bus size
into account, and does not double all Manual Mode Data Register access
sizes when communicating with a HyperFlash or Octal-SPI Flash device.

Fix this, and avoid the back-and-forth conversion between transfer size
and Transfer Data Enable bits, by explicitly storing the transfer size
in struct rpcif, and using that value to determine access size in
rpcif_reg_{read,write}().

Enforce that the "high" Manual Mode Read/Write Data Registers
(SM[RW]DR1) are only used for 8-byte data accesses.
While at it, forbid writing to the Manual Mode Read Data Registers,
as they are read-only.

Fixes: fff53a551db50f5e ("memory: renesas-rpc-if: Correct QSPI data transfer in Manual mode")
Signed-off-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Krzysztof Kozlowski <[email protected]>
Tested-by: Lad Prabhakar <[email protected]>
Tested-by: Wolfram Sang <[email protected]>
Reviewed-by: Wolfram Sang <[email protected]>
Link: https://lore.kernel.org/r/cde9bfacf704c81865f57b15d1b48a4793da4286.1649681476.git.geert+renesas@glider.be
Link: https://lore.kernel.org/r/[email protected]'
Signed-off-by: Arnd Bergmann <[email protected]>

0 files changed, 0 insertions, 0 deletions