drivers: memc: stm32: add support for st,mem-swap

Implements H7 FMC binding memory remap
or swap configuration.

Enables:
* sdram-sram - swaps the NOR/PSRAM and SDRAM banks.
* sdramb2 - remaps SDRAM bank 2.

Does nothing for 'disabled' value (default mapping, reset state).

Signed-off-by: Georgij Cernysiov <[email protected]>

Author: GeorgeCGV

drivers/memc/memc_stm32.c

@@ -4,16 +4,23 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#define DT_DRV_COMPAT st_stm32_fmc
-
 #include <device.h>
+#include <soc.h>
 
 #include <drivers/clock_control/stm32_clock_control.h>
 #include <drivers/pinctrl.h>
 
 #include <logging/log.h>
 LOG_MODULE_REGISTER(memc_stm32, CONFIG_MEMC_LOG_LEVEL);
 
+#if DT_HAS_COMPAT_STATUS_OKAY(st_stm32_fmc)
+#define DT_DRV_COMPAT st_stm32_fmc
+#elif DT_HAS_COMPAT_STATUS_OKAY(st_stm32h7_fmc)
+#define DT_DRV_COMPAT st_stm32h7_fmc
+#else
+#error "No compatible FMC devicetree node found"
+#endif
+
 struct memc_stm32_config {
 	uint32_t fmc;
 	struct stm32_pclken pclken;
@@ -43,6 +50,16 @@ static int memc_stm32_init(const struct device *dev)
 		return r;
 	}
 
+#if DT_HAS_COMPAT_STATUS_OKAY(st_stm32h7_fmc)
+#if (DT_ENUM_IDX(DT_DRV_INST(0), st_mem_swap) == 1)
+	/* sdram-sram */
+	MODIFY_REG(FMC_Bank1_R->BTCR[0], FMC_BCR1_BMAP, FMC_BCR1_BMAP_0);
+#elif (DT_ENUM_IDX(DT_DRV_INST(0), st_mem_swap) == 2)
+	/* sdramb2 */
+	MODIFY_REG(FMC_Bank1_R->BTCR[0], FMC_BCR1_BMAP, FMC_BCR1_BMAP_1);
+#endif
+#endif
+
 	return 0;
 }