tests: drivers: spi: controller_peripheral: add direct variant

Direct variant of this test disables intermediate buffer
in the nRF SPI driver and verifies whether devices like nRF54H20,
which can peform DMA transcations only from specific memory regions,
are handled properly.

Signed-off-by: Nikodem Kastelik <nikodem.kastelik@nordicsemi.no>

Author: nika-nordic

tests/drivers/spi/spi_controller_peripheral/boards/nrf54h20dk_nrf54h20_cpurad.overlay

@@ -5,6 +5,10 @@
  */
 #include "nrf54h20dk_nrf54h20_common.dtsi"
 
+&cpurad_dma_region {
+	reg = <0x1680 DT_SIZE_K(2)>;
+};
+
 &spi130 {
 	memory-regions = <&cpurad_dma_region>;
 };

tests/drivers/spi/spi_controller_peripheral/src/main.c

@@ -40,14 +40,8 @@ static struct k_poll_signal async_sig_spim = K_POLL_SIGNAL_INITIALIZER(async_sig
 static struct k_poll_event async_evt_spim =
 	K_POLL_EVENT_INITIALIZER(K_POLL_TYPE_SIGNAL, K_POLL_MODE_NOTIFY_ONLY, &async_sig_spim);
 
-#define MEMORY_SECTION(node)                                                                       \
-	COND_CODE_1(DT_NODE_HAS_PROP(node, memory_regions),                                        \
-		    (__attribute__((__section__(                                                   \
-			    LINKER_DT_NODE_REGION_NAME(DT_PHANDLE(node, memory_regions)))))),      \
-		    ())
-
-static uint8_t spim_buffer[32] MEMORY_SECTION(DT_BUS(DT_NODELABEL(dut_spi_dt)));
-static uint8_t spis_buffer[32] MEMORY_SECTION(DT_NODELABEL(dut_spis));
+static uint8_t spim_buffer[32];
+static uint8_t spis_buffer[32];
 
 struct test_data {
 	struct k_work_delayable test_work;

tests/drivers/spi/spi_controller_peripheral/testcase.yaml

@@ -102,3 +102,8 @@ tests:
       - CONFIG_PM_DEVICE=y
       - CONFIG_PM_DEVICE_RUNTIME=y
     filter: CONFIG_SOC_FAMILY_NORDIC_NRF
+
+  drivers.spi.direct_xfer:
+    extra_configs:
+      - CONFIG_SPI_NRFX_RAM_BUFFER_SIZE=0
+    filter: CONFIG_SOC_FAMILY_NORDIC_NRF