imxrt: FlexSPI allow RWW

arch/arm/src/imxrt/Kconfig

@@ -1871,12 +1871,28 @@ menuconfig IMXRT_FLEXSPI1
 	default n
 	select IMXRT_FLEXSPI
 
+menuconfig IMXRT_FLEXSPI1_XIP
+	bool "FLEXSPI1 is used for XIP"
+	default n
+	depends on IMXRT_FLEXSPI1
+	---help---
+		FlexSPI1 is used as XIP thus already
+		initialized by the bootloader
+
 menuconfig IMXRT_FLEXSPI2
 	bool "FLEXSPI2"
 	default n
 	select IMXRT_FLEXSPI
 	depends on IMXRT_HAVE_FLEXSPI2
 
+menuconfig IMXRT_FLEXSPI2_XIP
+	bool "FLEXSPI2 is used for XIP"
+	default n
+	depends on IMXRT_FLEXSPI2
+	---help---
+		FlexSPI2 is used as XIP thus already
+		initialized by the bootloader
+
 endmenu # FLEXSPI Peripherals
 
 menu "ADC Peripherals"

arch/arm/src/imxrt/imxrt_flexspi.c

@@ -83,6 +83,8 @@ static int imxrt_flexspi_lock(struct flexspi_dev_s *dev, bool lock);
 static int imxrt_flexspi_transfer_blocking(struct flexspi_dev_s *dev,
                                       struct flexspi_transfer_s *xfer);
 static void imxrt_flexspi_software_reset(struct flexspi_dev_s *dev);
+static void imxrt_flexspi_configure_prefetch(struct flexspi_dev_s *dev,
+                                             bool enable);
 static void imxrt_flexspi_update_lut(struct flexspi_dev_s *dev,
                                      uint32_t index,
                                      const uint32_t *cmd,
@@ -102,6 +104,7 @@ static const struct flexspi_ops_s g_flexspi0ops =
   .lock              = imxrt_flexspi_lock,
   .transfer_blocking = imxrt_flexspi_transfer_blocking,
   .software_reset    = imxrt_flexspi_software_reset,
+  .configure_prefetch = imxrt_flexspi_configure_prefetch,
   .update_lut        = imxrt_flexspi_update_lut,
   .set_device_config  = imxrt_flexspi_set_device_config,
 };
@@ -118,6 +121,9 @@ static struct imxrt_flexspidev_s g_flexspi0dev =
   },
   .base = (struct flexspi_type_s *)IMXRT_FLEXSPIC_BASE,
   .lock = NXMUTEX_INITIALIZER,
+#ifdef CONFIG_IMXRT_FLEXSPI1_XIP
+  .initialized = true,
+#endif
 };
 
 #endif
@@ -131,6 +137,9 @@ static struct imxrt_flexspidev_s g_flexspi1dev =
     .ops = &g_flexspi0ops,
   },
   .base = (struct flexspi_type_s *) IMXRT_FLEXSPI2C_BASE,
+#ifdef CONFIG_IMXRT_FLEXSPI2_XIP
+  .initialized = true,
+#endif
 };
 
 #endif
@@ -330,6 +339,31 @@ static inline void imxrt_flexspi_software_reset_private(
     }
 }
 
+/* Configure FLEXSPI preftech.
+ *
+ * This function enables/disabled the prefetcher
+ * Which is needed to do RWW see NXP AN12564
+ *
+ * @param base FLEXSPI peripheral base address.
+ */
+
+static inline void imxrt_flexspi_configure_prefetch_private(
+                        struct flexspi_type_s *base, bool enable)
+{
+  uint32_t config_value = base->AHBCR;
+
+  if (enable)
+    {
+      config_value |= FLEXSPI_AHBCR_PREFETCHEN(1);
+    }
+  else
+    {
+      config_value &= ~FLEXSPI_AHBCR_PREFETCHEN(1);
+    }
+
+  base->AHBCR = config_value;
+}
+
 /* Returns whether the bus is idle.
  *
  * @param base FLEXSPI peripheral base address.
@@ -1173,6 +1207,29 @@ static void imxrt_flexspi_software_reset(struct flexspi_dev_s *dev)
   imxrt_flexspi_software_reset_private(priv->base);
 }
 
+/****************************************************************************
+ * Name: imxrt_flexspi_configure_prefetch
+ *
+ * Description:
+ *   Configures prefetch
+ *
+ * Input Parameters:
+ *   dev  - Device-specific state data
+ *   enable - Enable prefetch
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void imxrt_flexspi_configure_prefetch(struct flexspi_dev_s *dev,
+                                             bool enable)
+{
+  struct imxrt_flexspidev_s *priv = (struct imxrt_flexspidev_s *)dev;
+
+  imxrt_flexspi_configure_prefetch_private(priv->base, enable);
+}
+
 /****************************************************************************
  * Name: imxrt_flexspi_update_lut
  *

arch/arm/src/imxrt/imxrt_flexspi.h

@@ -127,6 +127,23 @@
 
 #define FLEXSPI_TRANSFER(d,x) (d)->ops->transfer_blocking(d,x)
 
+/****************************************************************************
+ * Name: FLEXSPI_CONFIGURE_PREFTECH
+ *
+ * Description:
+ *   Enable / disable prefetch
+ *
+ * Input Parameters:
+ *   dev     - Device-specific state data
+ *   enable  - Enable prefetch
+ *
+ * Returned Value:
+ *   none
+ *
+ ****************************************************************************/
+
+#define FLEXSPI_CONFIGURE_PREFETCH(d,e) (d)->ops->configure_prefetch(d,e)
+
 /****************************************************************************
  * Name: FLEXSPI_SOFTWARE_RESET
  *
@@ -508,6 +525,7 @@ struct flexspi_ops_s
   int (*transfer_blocking)(struct flexspi_dev_s *dev,
                            struct flexspi_transfer_s *xfer);
   void (*software_reset)(struct flexspi_dev_s *dev);
+  void (*configure_prefetch)(struct flexspi_dev_s *dev, bool enable);
   void (*update_lut)(struct flexspi_dev_s *dev,
                      uint32_t index, const uint32_t *cmd,
                      uint32_t count);

arch/arm/src/imxrt/imxrt_periphclks.h

@@ -259,6 +259,7 @@
 #define imxrt_clockrun_flexram()          imxrt_periphclk_configure(CCM_CCGR_FLEXRAM, CCM_CG_RUN)
 #ifndef CONFIG_ARCH_FAMILY_IMXRT117x
 #  define imxrt_clockrun_flexspi()        imxrt_periphclk_configure(CCM_CCGR_FLEXSPI, CCM_CG_RUN)
+#  define imxrt_clockrun_flexspi2()       imxrt_periphclk_configure(CCM_CCGR_FLEXSPI2, CCM_CG_RUN)
 #else
 #  define imxrt_clockrun_flexspi()        imxrt_periphclk_configure(CCM_CCGR_FLEXSPI1, CCM_CG_RUN)
 #  define imxrt_clockrun_flexspi2()       imxrt_periphclk_configure(CCM_CCGR_FLEXSPI2, CCM_CG_RUN)