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 <[email protected]>

Author: nika-nordic

tests/drivers/spi/spi_controller_peripheral/Kconfig

@@ -11,4 +11,11 @@ config TESTED_SPI_MODE
 		2: CPOL 1 (Active low), CPHA 0 (leading)
 		3: CPOL 1 (Active low), CPHA 1 (trailing)
 
+config PREALLOC_BUFFERS
+	bool "Preallocate buffers"
+	default y
+	help
+		Preallocate buffers used for transaction
+		using `memory-region` property.
+
 source "Kconfig.zephyr"

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

@@ -41,9 +41,12 @@ 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)))))),      \
+	COND_CODE_1(IS_ENABLED(CONFIG_PREALLOC_BUFFERS),                                           \
+		    (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)));

tests/drivers/spi/spi_controller_peripheral/testcase.yaml

@@ -116,3 +116,14 @@ tests:
       - nrf54h20dk/nrf54h20/cpurad
       - nrf54h20dk/nrf54h20/cpuppr
       - ophelia4ev/nrf54l15/cpuapp
+
+  drivers.spi.direct_xfer:
+    extra_configs:
+      - CONFIG_SPI_NRFX_RAM_BUFFER_SIZE=0
+    filter: CONFIG_SOC_FAMILY_NORDIC_NRF
+
+  drivers.spi.direct_xfer.no_prealloc:
+    extra_configs:
+      - CONFIG_SPI_NRFX_RAM_BUFFER_SIZE=0
+      - CONFIG_PREALLOC_BUFFERS=n
+    filter: CONFIG_SOC_FAMILY_NORDIC_NRF