ports/rp2: PSRAM: Fix RP2040/Pico build.

Signed-off-by: Phil Howard <[email protected]>

Author: Gadgetoid

ports/rp2/CMakeLists.txt

@@ -165,7 +165,6 @@ set(MICROPY_SOURCE_PORT
     pendsv.c
     rp2_flash.c
     rp2_pio.c
-    rp2_psram.c
     rp2_dma.c
     uart.c
     usbd.c
@@ -174,6 +173,12 @@ set(MICROPY_SOURCE_PORT
     ${CMAKE_BINARY_DIR}/pins_${MICROPY_BOARD}.c
 )
 
+if(PICO_RP2350)
+    list(APPEND MICROPY_SOURCE_PORT
+        rp2_psram.c
+    )
+endif()
+
 set(MICROPY_SOURCE_QSTR
     ${MICROPY_SOURCE_PY}
     ${MICROPY_DIR}/shared/readline/readline.c

ports/rp2/rp2_flash.c

@@ -89,11 +89,13 @@ static uint32_t begin_critical_flash_section(void) {
     }
     uint32_t state = save_and_disable_interrupts();
 
+    #if defined(MICROPY_HW_PSRAM_CS_PIN) && MICROPY_HW_ENABLE_PSRAM
     // We're about to invalidate the XIP cache, clean it first to commit any dirty writes to PSRAM
     uint8_t *maintenance_ptr = (uint8_t *)XIP_MAINTENANCE_BASE;
     for (int i = 1; i < 16 * 1024; i += 8) {
         maintenance_ptr[i] = 0;
     }
+    #endif
 
     return state;
 }