drivers: flash: nrf_qspi_nor: unaligned read offset & read lenght

drivers/flash/nrf_qspi_nor.c

@@ -31,6 +31,8 @@
 #define QSPI_PROP_AT(prop, idx) DT_PROP_BY_IDX(QSPI_NODE, prop, idx)
 #define QSPI_PROP_LEN(prop) DT_PROP_LEN(QSPI_NODE, prop)
 
+#define WORD_SIZE 4
+
 LOG_MODULE_REGISTER(qspi_nor, CONFIG_FLASH_LOG_LEVEL);
 
 static const struct flash_parameters qspi_flash_parameters = {
@@ -503,27 +505,86 @@ static inline int qspi_nor_read_id(struct device *dev,
 	return 0;
 }
 
+static inline nrfx_err_t read_non_aligned(struct device *dev, off_t addr,
+					  void *dest, size_t size)
+{
+	uint8_t __aligned(WORD_SIZE) buf[WORD_SIZE * 2];
+	uint8_t *dptr = dest;
+
+	off_t flash_prefix = (WORD_SIZE - (addr % WORD_SIZE)) % WORD_SIZE;
+
+	if (flash_prefix > size) {
+		flash_prefix = size;
+	}
+
+	off_t dest_prefix = (WORD_SIZE - (off_t)dptr % WORD_SIZE) % WORD_SIZE;
+
+	if (dest_prefix > size) {
+		dest_prefix = size;
+	}
+
+	off_t flash_suffix = (size - flash_prefix) % WORD_SIZE;
+	off_t flash_middle = size - flash_prefix - flash_suffix;
+	off_t dest_middle = size - dest_prefix -
+			    (size - dest_prefix) % WORD_SIZE;
+
+	if (flash_middle > dest_middle) {
+		flash_middle = dest_middle;
+		flash_suffix = size - flash_prefix - flash_middle;
+	}
+
+	nrfx_err_t res = NRFX_SUCCESS;
+
+	/* read from aligned flash to aligned memory */
+	if (flash_middle != 0) {
+		res = nrfx_qspi_read(dptr + dest_prefix, flash_middle,
+				     addr + flash_prefix);
+		qspi_wait_for_completion(dev, res);
+		if (res != NRFX_SUCCESS) {
+			return res;
+		}
+
+		/* perform shift in RAM */
+		if (flash_prefix != dest_prefix) {
+			memmove(dptr + flash_prefix, dptr + dest_prefix, flash_middle);
+		}
+	}
+
+	/* read prefix */
+	if (flash_prefix != 0) {
+		res = nrfx_qspi_read(buf, WORD_SIZE, addr -
+				     (WORD_SIZE - flash_prefix));
+		qspi_wait_for_completion(dev, res);
+		if (res != NRFX_SUCCESS) {
+			return res;
+		}
+		memcpy(dptr, buf + WORD_SIZE - flash_prefix, flash_prefix);
+	}
+
+	/* read suffix */
+	if (flash_suffix != 0) {
+		res = nrfx_qspi_read(buf, WORD_SIZE * 2,
+				     addr + flash_prefix + flash_middle);
+		qspi_wait_for_completion(dev, res);
+		if (res != NRFX_SUCCESS) {
+			return res;
+		}
+		memcpy(dptr + flash_prefix + flash_middle, buf, flash_suffix);
+	}
+
+	return res;
+}
+
 static int qspi_nor_read(struct device *dev, off_t addr, void *dest,
 			 size_t size)
 {
-	void *dptr = dest;
-	size_t dlen = size;
-	uint8_t __aligned(4) buf[4];
-
 	if (!dest) {
 		return -EINVAL;
 	}
 
-	/* read size must be non-zero multiple of 4 bytes */
-	if ((size > 0) && (size < 4U)) {
-		dest = buf;
-		size = sizeof(buf);
-	} else if (((size % 4U) != 0) || (size == 0)) {
-		return -EINVAL;
-	}
-	/* address must be 4-byte aligned */
-	if ((addr % 4U) != 0) {
-		return -EINVAL;
+	/* read size must be non-zero */
+	if (!size) {
+		return 0;
 	}
 
 	const struct qspi_nor_config *params = dev->config_info;
@@ -539,18 +600,12 @@ static int qspi_nor_read(struct device *dev, off_t addr, void *dest,
 
 	qspi_lock(dev);
 
-	nrfx_err_t res = nrfx_qspi_read(dest, size, addr);
-
-	qspi_wait_for_completion(dev, res);
+	nrfx_err_t res = read_non_aligned(dev, addr, dest, size);
 
 	qspi_unlock(dev);
 
 	int rc = qspi_get_zephyr_ret_code(res);
 
-	if ((rc == 0) && (dest != dptr)) {
-		memcpy(dptr, dest, dlen);
-	}
-
 	return rc;
 }
 

tests/drivers/flash/CMakeLists.txt

@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.13.1)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(nrf_qspi_nor)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

tests/drivers/flash/boards/nrf52840_flash_qspi.conf

@@ -0,0 +1,4 @@
+# Minimal configuration for testing flash driver
+# on nrf52840dk_nrf52840 board
+
+CONFIG_NORDIC_QSPI_NOR=y

tests/drivers/flash/boards/nrf52840_flash_soc.conf

@@ -0,0 +1,4 @@
+# Minimal configuration for testing flash driver
+# on nrf52840dk_nrf52840 board
+
+CONFIG_MPU_ALLOW_FLASH_WRITE=y

tests/drivers/flash/prj.conf

@@ -0,0 +1,3 @@
+CONFIG_TEST=y
+CONFIG_ZTEST=y
+CONFIG_FLASH=y

tests/drivers/flash/src/main.c

@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2020 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr.h>
+#include <ztest.h>
+#include <drivers/flash.h>
+#include <devicetree.h>
+#include <storage/flash_map.h>
+
+#if (CONFIG_NORDIC_QSPI_NOR - 0)
+#define FLASH_DEVICE DT_LABEL(DT_INST(0, nordic_qspi_nor))
+#define FLASH_TEST_REGION_OFFSET 0xff000
+#define TEST_AREA_MAX DT_PROP(DT_INST(0, nordic_qspi_nor), size)
+#else
+
+/* SoC emebded NVM */
+#define FLASH_DEVICE DT_CHOSEN_ZEPHYR_FLASH_CONTROLLER_LABEL
+
+#ifdef CONFIG_TRUSTED_EXECUTION_NONSECURE
+#define FLASH_TEST_REGION_OFFSET FLASH_AREA_OFFSET(image_1_nonsecure)
+#define TEST_AREA_MAX (FLASH_TEST_REGION_OFFSET +\
+		       FLASH_AREA_SIZE(image_1_nonsecure))
+#else
+#define FLASH_TEST_REGION_OFFSET FLASH_AREA_OFFSET(image_1)
+#define TEST_AREA_MAX (FLASH_TEST_REGION_OFFSET + FLASH_AREA_SIZE(image_1))
+#endif
+
+#endif
+
+#define EXPECTED_SIZE	256
+#define CANARY		0xff
+
+static struct device *flash_dev;
+static struct flash_pages_info page_info;
+static uint8_t __aligned(4) expected[EXPECTED_SIZE];
+
+static void test_setup(void)
+{
+	int rc;
+
+	flash_dev = device_get_binding(FLASH_DEVICE);
+	const struct flash_parameters *qspi_flash_parameters =
+			flash_get_parameters(flash_dev);
+
+	/* For tests purposes use page (in nrf_qspi_nor page = 64 kB) */
+	flash_get_page_info_by_offs(flash_dev, FLASH_TEST_REGION_OFFSET,
+				    &page_info);
+
+	/* Check if test region is not empty */
+	uint8_t buf[EXPECTED_SIZE];
+
+	rc = flash_read(flash_dev, FLASH_TEST_REGION_OFFSET,
+			buf, EXPECTED_SIZE);
+	zassert_equal(rc, 0, "Cannot read flash");
+
+	/* Fill test buffer with random data */
+	for (int i = 0; i < EXPECTED_SIZE; i++) {
+		expected[i] = i;
+	}
+
+	/* Check if tested region fits in flash */
+	zassert_true((FLASH_TEST_REGION_OFFSET + EXPECTED_SIZE) < TEST_AREA_MAX,
+		     "Test area exceeds flash size");
+
+	/* Check if flash is cleared */
+	bool is_buf_clear = true;
+
+	for (off_t i = 0; i < EXPECTED_SIZE; i++) {
+		if (buf[i] != qspi_flash_parameters->erase_value) {
+			is_buf_clear = false;
+			break;
+		}
+	}
+
+	if (!is_buf_clear) {
+		/* erase page */
+		rc = flash_erase(flash_dev, page_info.start_offset,
+				 page_info.size);
+		zassert_equal(rc, 0, "Flash memory not properly erased");
+	}
+
+}
+
+static void test_read_unaligned_address(void)
+{
+	int rc;
+	uint8_t buf[EXPECTED_SIZE];
+
+	rc = flash_write(flash_dev,
+			 page_info.start_offset,
+			 expected, EXPECTED_SIZE);
+	zassert_equal(rc, 0, "Cannot write to flash");
+
+	/* read buffer length*/
+	for (off_t len = 0; len < 25; len++) {
+		/* address offset */
+		for (off_t ad_o = 0; ad_o < 4; ad_o++) {
+			/* buffer offset; leave space for buffer guard */
+			for (off_t buf_o = 1; buf_o < 5; buf_o++) {
+				/* buffer overflow protection */
+				buf[buf_o - 1] = CANARY;
+				buf[buf_o + len] = CANARY;
+				memset(buf + buf_o, 0, len);
+				rc = flash_read(flash_dev,
+						page_info.start_offset + ad_o,
+						buf + buf_o, len);
+				zassert_equal(rc, 0, "Cannot read flash");
+				zassert_equal(memcmp(buf + buf_o,
+						expected + ad_o,
+						len),
+					0, "Flash read failed at len=%d, "
+					"ad_o=%d, buf_o=%d", len, ad_o, buf_o);
+				/* check buffer guards */
+				zassert_equal(buf[buf_o - 1], CANARY,
+					"Buffer underflow at len=%d, "
+					"ad_o=%d, buf_o=%d", len, ad_o, buf_o);
+				zassert_equal(buf[buf_o + len], CANARY,
+					"Buffer overflow at len=%d, "
+					"ad_o=%d, buf_o=%d", len, ad_o, buf_o);
+			}
+		}
+	}
+}
+
+void test_main(void)
+{
+	ztest_test_suite(flash_driver_test,
+		ztest_unit_test(test_setup),
+		ztest_unit_test(test_read_unaligned_address)
+	);
+
+	ztest_run_test_suite(flash_driver_test);
+}

tests/drivers/flash/testcase.yaml

@@ -0,0 +1,9 @@
+tests:
+  drivers.flash.nrf_qspi_nor:
+    platform_whitelist: nrf52840dk_nrf52840
+    tags: flash nrf52 nrf_qspi_fash
+    extra_args: OVERLAY_CONFIG=boards/nrf52840_flash_qspi.conf
+  drivers.flash.soc_flash_nrf:
+    platform_whitelist: nrf52840dk_nrf52840
+    tags: nrf52 soc_flash_nrf
+    extra_args: OVERLAY_CONFIG=boards/nrf52840_flash_soc.conf