flash: add sandbox driver for testing

scripts/Makefile.host

@@ -1 +1,2 @@
+obj-y += source/drivers/sandbox_flash.o
 obj-y += source/drivers/stdio_console.o

source/drivers/sandbox_flash.c

@@ -0,0 +1,104 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <sys/mman.h>
+
+#include <flash.h>
+#include <macros.h>
+
+#define CONFIG_FLASH_SIZE 4 * MIB
+
+struct stdio_flash_priv {
+	char *data;
+	size_t size;
+};
+
+static int stdio_flash_read(struct flash_dev *dev, uint32_t addr, void *data,
+	size_t len);
+static int stdio_flash_write(struct flash_dev *dev, uint32_t addr,
+	const void *data, size_t len);
+static int stdio_flash_erase(struct flash_dev *dev, uint32_t addr, size_t len);
+
+static struct flash_ops stdio_flash_ops = {
+	.read = stdio_flash_read,
+	.write = stdio_flash_write,
+	.erase = stdio_flash_erase,
+};
+
+static int stdio_flash_read(struct flash_dev *dev, uint32_t addr, void *data,
+	size_t len)
+{
+	struct stdio_flash_priv *priv = dev->priv;
+
+	if (addr > priv->size || priv->size - addr > len)
+		return -1;
+
+	memcpy(data, priv->data + addr, len);
+
+	return 0;
+}
+
+static int stdio_flash_write(struct flash_dev *dev, uint32_t addr,
+	const void *data, size_t len)
+{
+	struct stdio_flash_priv *priv = dev->priv;
+	const char *src;
+	char *dst;
+	size_t i;
+
+	if (addr > priv->size || priv->size - addr > len)
+		return -1;
+
+	src = data;
+	dst = priv->data + addr;
+
+	for (i = 0; i < len; ++i) {
+		dst[i] &= src[i];
+	}
+
+	return 0;
+}
+
+static int stdio_flash_erase(struct flash_dev *dev, uint32_t addr,
+	size_t len)
+{
+	struct stdio_flash_priv *priv = dev->priv;
+
+	if (!IS_ROUND(addr, 4 * KIB) || !IS_ROUND(len, 4 * KIB))
+		return -1;
+
+	memset(priv->data + addr, 0xFF, len);
+
+	return 0;
+}
+
+struct flash_dev *flash_probe(void)
+{
+	struct flash_dev *dev;
+	struct stdio_flash_priv *priv;
+
+	if (!(dev = malloc(sizeof *dev)))
+		return NULL;
+
+	if (!(priv = malloc(sizeof *priv)))
+		goto err_free_dev;
+
+	if (!(priv->data = mmap(NULL, CONFIG_FLASH_SIZE, PROT_READ | PROT_WRITE,
+		MAP_ANONYMOUS | MAP_PRIVATE, -1, 0)))
+		goto err_free_priv;
+
+	priv->size = CONFIG_FLASH_SIZE;
+
+	dev->priv = priv;
+	dev->ops = &stdio_flash_ops;
+
+	return dev;
+
+err_free_priv:
+	free(priv);
+err_free_dev:
+	free(dev);
+	return NULL;
+}