memory: Add STM32 Octo Memory Manager driver

Octo Memory Manager driver (OMM) manages:
  - the muxing between 2 OSPI busses and 2 output ports.
    There are 4 possible muxing configurations:
      - direct mode (no multiplexing): OSPI1 output is on port 1 and OSPI2
        output is on port 2
      - OSPI1 and OSPI2 are multiplexed over the same output port 1
      - swapped mode (no multiplexing), OSPI1 output is on port 2,
        OSPI2 output is on port 1
      - OSPI1 and OSPI2 are multiplexed over the same output port 2
  - the split of the memory area shared between the 2 OSPI instances.
  - chip select selection override.
  - the time between 2 transactions in multiplexed mode.
  - check firewall access.

Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Link: https://lore.kernel.org/r/20250428-upstream_ospi_v6-v11-2-1548736fd9d2@foss.st.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Author: Patrice Chotard

drivers/memory/Kconfig

@@ -225,6 +225,23 @@ config STM32_FMC2_EBI
 	  devices (like SRAM, ethernet adapters, FPGAs, LCD displays, ...) on
 	  SOCs containing the FMC2 External Bus Interface.
 
+config STM32_OMM
+	tristate "STM32 Octo Memory Manager"
+	depends on SPI_STM32_OSPI || COMPILE_TEST
+	help
+	  This driver manages the muxing between the 2 OSPI busses and
+	  the 2 output ports. There are 4 possible muxing configurations:
+	  - direct mode (no multiplexing): OSPI1 output is on port 1 and OSPI2
+	       output is on port 2
+	  - OSPI1 and OSPI2 are multiplexed over the same output port 1
+	  - swapped mode (no multiplexing), OSPI1 output is on port 2,
+	       OSPI2 output is on port 1
+	  - OSPI1 and OSPI2 are multiplexed over the same output port 2
+	  It also manages :
+	    - the split of the memory area shared between the 2 OSPI instances.
+	    - chip select selection override.
+	    - the time between 2 transactions in multiplexed mode.
+
 source "drivers/memory/samsung/Kconfig"
 source "drivers/memory/tegra/Kconfig"
 

drivers/memory/Makefile

@@ -24,6 +24,7 @@ obj-$(CONFIG_DA8XX_DDRCTL)	+= da8xx-ddrctl.o
 obj-$(CONFIG_PL353_SMC)		+= pl353-smc.o
 obj-$(CONFIG_RENESAS_RPCIF)	+= renesas-rpc-if.o
 obj-$(CONFIG_STM32_FMC2_EBI)	+= stm32-fmc2-ebi.o
+obj-$(CONFIG_STM32_OMM)		+= stm32_omm.o
 
 obj-$(CONFIG_SAMSUNG_MC)	+= samsung/
 obj-$(CONFIG_TEGRA_MC)		+= tegra/