Hi all,
This series adds support for the embedded Cadence Quad SPI controller on
Mobileye EyeQ5. In our case "quad" is inappropriate as we support
octal. Most patches aim to improve performance and avoid interrupts.
Stuff to talk about:
- Both IRQ handler and read operation callbacks called
of_device_get_match_data(). This has a cost which we avoid.
- Add a flag to detect FIFO depth at runtime. The SRAMPARTITION
register is partially read-only: writel() then readl() to get the
depth.
This implies cdns,fifo-depth devicetree property is unused on this
platform.
- Add a flag to avoid IRQs for indirect reads. Hardware is way too fast
for sleeping to make sense.
- Add a flag to busywait in read operations. We avoid many hrtimer
interrupts this way. Fallback to sleeping, which shouldn't happen.
- End this by adding the compatible to the driver, add the controller
to the SoC devicetree and add an octal flash to the eval board
devicetree.
Dependencies:
- Devicetree:
- Patches [0][1] adding platform DTS, found in mips-next [2].
- System-controller series [3] for <&clocks> phandle.
- Driver: patches that fix this driver's runtime PM, see spi-next [4].
Have a nice day,
Théo
[0]: https://lore.kernel.org/lkml/20240216174227.409400-1-gregory.clement@xxxxxxxxxxx/
[1]: https://lore.kernel.org/linux-mips/20240209-regname-v1-0-2125efa016ef@xxxxxxxxxxx/
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/mips/linux.git/log/
[3]: https://lore.kernel.org/lkml/20240301-mbly-clk-v9-0-cbf06eb88708@xxxxxxxxxxx/
[4]: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git/log/
Signed-off-by: Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
---
Théo Lebrun (11):
dt-bindings: qspi: cdns,qspi-nor: add mobileye,eyeq5-ospi compatible
spi: cadence-qspi: switch from legacy names to modern ones
spi: cadence-qspi: allow building for MIPS
spi: cadence-qspi: store device data pointer in private struct
spi: cadence-qspi: add FIFO depth detection quirk
spi: cadence-qspi: minimise register accesses on each op if !DTR
spi: cadence-qspi: add no-IRQ mode to indirect reads
spi: cadence-qspi: add early busywait to cqspi_wait_for_bit()
spi: cadence-qspi: add mobileye,eyeq5-ospi compatible
MIPS: mobileye: eyeq5: Add SPI-NOR controller node
MIPS: mobileye: eyeq5: add octal flash node to eval board DTS
.../devicetree/bindings/spi/cdns,qspi-nor.yaml | 13 ++-
arch/mips/boot/dts/mobileye/eyeq5-epm5.dts | 15 +++
arch/mips/boot/dts/mobileye/eyeq5.dtsi | 15 +++
drivers/spi/Kconfig | 2 +-
drivers/spi/spi-cadence-quadspi.c | 116 +++++++++++++++------
5 files changed, 130 insertions(+), 31 deletions(-)
---
base-commit: ecd5ff483c763ca368f815fafc954f6db9788143
change-id: 20240209-cdns-qspi-mbly-de2205a44ab3
Best regards,
--
Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
