drivers/flash/flash_simulator: Added file back end for posix arch

Extended flash simulator for posix architecture to read/write data
from a binary file on the host file system.

Further enable the flash simulator by default on native_posix(_64)
boards and updated the documentation accordingly.

Signed-off-by: Jan Van Winkel <jan.van_winkel@dxplore.eu>

boards/posix/native_posix/Kconfig.defconfig

@@ -90,7 +90,7 @@ endif # TRACING_CTF
 
 if FLASH
 
-config FLASH_NATIVE_POSIX
+config FLASH_SIMULATOR
 	default y
 
 endif # FLASH

boards/posix/native_posix/doc/index.rst

@@ -537,17 +537,9 @@ The following peripherals are currently provided with this board:
 
 **Flash driver**:
   A flash driver is provided that accesses all flash data through a binary file
-  on the host file system.
+  on the host file system. The behavior of the flash device can be configured
-
+  through the native POSIX board devicetree or Kconfig settings under
-  The size of the flash device can be configured through the native POSIX board
+  :option:`CONFIG_FLASH_SIMULATOR`.
-  devicetree and the sector size is configurable via the Kconfig option
-  :option:`CONFIG_FLASH_NATIVE_POSIX_SECTOR_SIZE`. The sector size will only be
-  used to return flash page layout related information and no restrictions are
-  imposed by the driver based on the configured sector size. As such an erase
-  operation of arbitrary size will succeed on the emulated flash device.
-  Further the emulated device will not impose any write restriction that are
-  applicable for a regular flash device, including changing the state of a bit
-  from zero to one.
 
   By default the binary data is located in the file *flash.bin* in the current
   working directory. The location of this file can be changed through the

boards/posix/native_posix/dts_fixup.h

@@ -4,6 +4,6 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#define DT_FLASH_DEV_NAME   DT_INST_0_ZEPHYR_NATIVE_POSIX_FLASH_CONTROLLER_LABEL
+#define DT_FLASH_DEV_NAME   DT_INST_0_ZEPHYR_SIM_FLASH_LABEL
 #define DT_UART_0_DEV_NAME  DT_ZEPHYR_NATIVE_POSIX_UART_UART_LABEL
 

boards/posix/native_posix/native_posix.dts

@@ -23,7 +23,7 @@
 	};
 
 	flashcontroller0: flash-controller@0 {
-		compatible = "zephyr,native-posix-flash-controller";
+		compatible = "zephyr,sim-flash";
 		reg = <0x00000000 DT_SIZE_K(2048)>;
 
 		#address-cells = <1>;
@@ -35,7 +35,7 @@
 			status = "okay";
 			compatible = "soc-nv-flash";
 			label = "flash";
-			erase-block-size = <1>;
+			erase-block-size = <4096>;
 			write-block-size = <1>;
 			reg = <0x00000000 DT_SIZE_K(2048)>;
 

drivers/flash/flash_simulator.c

@@ -13,11 +13,34 @@
 #include <stats/stats.h>
 #include <string.h>
 
+#ifdef CONFIG_ARCH_POSIX
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include "cmdline.h"
+#include "soc.h"
+
+#endif /* CONFIG_ARCH_POSIX */
+
 /* configuration derived from DT */
+#ifdef CONFIG_ARCH_POSIX
+#define FLASH_SIMULATOR_BASE_OFFSET DT_FLASH_BASE_ADDRESS
+#define FLASH_SIMULATOR_ERASE_UNIT DT_FLASH_ERASE_BLOCK_SIZE
+#define FLASH_SIMULATOR_PROG_UNIT DT_FLASH_WRITE_BLOCK_SIZE
+#define FLASH_SIMULATOR_FLASH_SIZE (DT_FLASH_SIZE * 1024)
+#define FLASH_SIMULATOR_DEV_NAME DT_FLASH_DEV_NAME
+#else
 #define FLASH_SIMULATOR_BASE_OFFSET DT_FLASH_SIM_BASE_ADDRESS
 #define FLASH_SIMULATOR_ERASE_UNIT DT_FLASH_SIM_ERASE_BLOCK_SIZE
 #define FLASH_SIMULATOR_PROG_UNIT DT_FLASH_SIM_WRITE_BLOCK_SIZE
 #define FLASH_SIMULATOR_FLASH_SIZE DT_FLASH_SIM_SIZE
+#define FLASH_SIMULATOR_DEV_NAME "FLASH_SIMULATOR"
+#endif /* CONFIG_ARCH_POSIX */
 
 #define FLASH_SIMULATOR_PAGE_COUNT (FLASH_SIMULATOR_FLASH_SIZE / \
 				    FLASH_SIMULATOR_ERASE_UNIT)
@@ -102,7 +125,15 @@ STATS_NAME(flash_sim_thresholds, max_erase_calls)
 STATS_NAME(flash_sim_thresholds, max_len)
 STATS_NAME_END(flash_sim_thresholds);
 
+#ifdef CONFIG_ARCH_POSIX
+static u8_t *mock_flash;
+static int flash_fd = -1;
+static const char *flash_file_path;
+static const char default_flash_file_path[] = "flash.bin";
+#else
 static u8_t mock_flash[FLASH_SIMULATOR_FLASH_SIZE];
+#endif /* CONFIG_ARCH_POSIX */
+
 static bool write_protection;
 
 static const struct flash_driver_api flash_sim_api;
@@ -322,16 +353,96 @@ static const struct flash_driver_api flash_sim_api = {
 #endif
 };
 
+#ifdef CONFIG_ARCH_POSIX
+
+static int flash_mock_init(struct device *dev)
+{
+	if (flash_file_path == NULL) {
+		flash_file_path = default_flash_file_path;
+	}
+
+	flash_fd = open(flash_file_path, O_RDWR | O_CREAT, (mode_t)0600);
+	if (flash_fd == -1) {
+		posix_print_warning("Failed to open flash device file "
+				    "%s: %s\n",
+				    flash_file_path, strerror(errno));
+		return -EIO;
+	}
+
+	if (ftruncate(flash_fd, FLASH_SIMULATOR_FLASH_SIZE) == -1) {
+		posix_print_warning("Failed to resize flash device file "
+				    "%s: %s\n",
+				    flash_file_path, strerror(errno));
+		return -EIO;
+	}
+
+	mock_flash = mmap(NULL, FLASH_SIMULATOR_FLASH_SIZE,
+			  PROT_WRITE | PROT_READ, MAP_SHARED, flash_fd, 0);
+	if (mock_flash == MAP_FAILED) {
+		posix_print_warning("Failed to mmap flash device file "
+				    "%s: %s\n",
+				    flash_file_path, strerror(errno));
+		return -EIO;
+	}
+
+	return 0;
+}
+
+#else
+
+static int flash_mock_init(struct device *dev)
+{
+	memset(mock_flash, 0xFF, ARRAY_SIZE(mock_flash));
+	return 0;
+}
+
+#endif /* CONFIG_ARCH_POSIX */
+
 static int flash_init(struct device *dev)
 {
 	STATS_INIT_AND_REG(flash_sim_stats, STATS_SIZE_32, "flash_sim_stats");
 	STATS_INIT_AND_REG(flash_sim_thresholds, STATS_SIZE_32,
 			   "flash_sim_thresholds");
-	memset(mock_flash, 0xFF, ARRAY_SIZE(mock_flash));
+	return flash_mock_init(dev);
-
-	return 0;
 }
 
-DEVICE_AND_API_INIT(flash_simulator, "FLASH_SIMULATOR", flash_init, NULL, NULL,
+DEVICE_AND_API_INIT(flash_simulator, FLASH_SIMULATOR_DEV_NAME, flash_init,
-		    POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
+		    NULL, NULL, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
 		    &flash_sim_api);
+
+#ifdef CONFIG_ARCH_POSIX
+
+static void flash_native_posix_cleanup(void)
+{
+	if ((mock_flash != MAP_FAILED) && (mock_flash != NULL)) {
+		munmap(mock_flash, FLASH_SIMULATOR_FLASH_SIZE);
+	}
+
+	if (flash_fd != -1) {
+		close(flash_fd);
+	}
+}
+
+static void flash_native_posix_options(void)
+{
+	static struct args_struct_t flash_options[] = {
+		{ .manual = false,
+		  .is_mandatory = false,
+		  .is_switch = false,
+		  .option = "flash",
+		  .name = "path",
+		  .type = 's',
+		  .dest = (void *)&flash_file_path,
+		  .call_when_found = NULL,
+		  .descript = "Path to binary file to be used as flash" },
+		ARG_TABLE_ENDMARKER
+	};
+
+	native_add_command_line_opts(flash_options);
+}
+
+
+NATIVE_TASK(flash_native_posix_options, PRE_BOOT_1, 1);
+NATIVE_TASK(flash_native_posix_cleanup, ON_EXIT, 1);
+
+#endif /* CONFIG_ARCH_POSIX */

tests/subsys/fs/littlefs/boards/native_posix.conf

@@ -1 +0,0 @@
-CONFIG_FLASH_NATIVE_POSIX_SECTOR_SIZE=4

tests/subsys/fs/littlefs/boards/native_posix_64.conf

@@ -1 +0,0 @@
-CONFIG_FLASH_NATIVE_POSIX_SECTOR_SIZE=4