Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 159 insertions, 0 deletions

diff --git a/drivers/mtd/chips/map_ram.c b/drivers/mtd/chips/map_ram.c
new file mode 100644
index 0000000000..e8dd649692
--- /dev/null
+++ b/drivers/mtd/chips/map_ram.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common code to handle map devices which are simple RAM
+ * (C) 2000 Red Hat.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <asm/io.h>
+#include <asm/byteorder.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+
+
+static int mapram_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
+static int mapram_write (struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
+static int mapram_erase (struct mtd_info *, struct erase_info *);
+static void mapram_nop (struct mtd_info *);
+static struct mtd_info *map_ram_probe(struct map_info *map);
+static int mapram_point (struct mtd_info *mtd, loff_t from, size_t len,
+			 size_t *retlen, void **virt, resource_size_t *phys);
+static int mapram_unpoint(struct mtd_info *mtd, loff_t from, size_t len);
+
+
+static struct mtd_chip_driver mapram_chipdrv = {
+	.probe	= map_ram_probe,
+	.name	= "map_ram",
+	.module	= THIS_MODULE
+};
+
+static struct mtd_info *map_ram_probe(struct map_info *map)
+{
+	struct mtd_info *mtd;
+
+	/* Check the first byte is RAM */
+#if 0
+	map_write8(map, 0x55, 0);
+	if (map_read8(map, 0) != 0x55)
+		return NULL;
+
+	map_write8(map, 0xAA, 0);
+	if (map_read8(map, 0) != 0xAA)
+		return NULL;
+
+	/* Check the last byte is RAM */
+	map_write8(map, 0x55, map->size-1);
+	if (map_read8(map, map->size-1) != 0x55)
+		return NULL;
+
+	map_write8(map, 0xAA, map->size-1);
+	if (map_read8(map, map->size-1) != 0xAA)
+		return NULL;
+#endif
+	/* OK. It seems to be RAM. */
+
+	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
+	if (!mtd)
+		return NULL;
+
+	map->fldrv = &mapram_chipdrv;
+	mtd->priv = map;
+	mtd->name = map->name;
+	mtd->type = MTD_RAM;
+	mtd->size = map->size;
+	mtd->_erase = mapram_erase;
+	mtd->_read = mapram_read;
+	mtd->_write = mapram_write;
+	mtd->_panic_write = mapram_write;
+	mtd->_point = mapram_point;
+	mtd->_sync = mapram_nop;
+	mtd->_unpoint = mapram_unpoint;
+	mtd->flags = MTD_CAP_RAM;
+	mtd->writesize = 1;
+
+	mtd->erasesize = PAGE_SIZE;
+ 	while(mtd->size & (mtd->erasesize - 1))
+		mtd->erasesize >>= 1;
+
+	__module_get(THIS_MODULE);
+	return mtd;
+}
+
+static int mapram_point(struct mtd_info *mtd, loff_t from, size_t len,
+			size_t *retlen, void **virt, resource_size_t *phys)
+{
+	struct map_info *map = mtd->priv;
+
+	if (!map->virt)
+		return -EINVAL;
+	*virt = map->virt + from;
+	if (phys)
+		*phys = map->phys + from;
+	*retlen = len;
+	return 0;
+}
+
+static int mapram_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
+{
+	return 0;
+}
+
+static int mapram_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
+{
+	struct map_info *map = mtd->priv;
+
+	map_copy_from(map, buf, from, len);
+	*retlen = len;
+	return 0;
+}
+
+static int mapram_write (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf)
+{
+	struct map_info *map = mtd->priv;
+
+	map_copy_to(map, to, buf, len);
+	*retlen = len;
+	return 0;
+}
+
+static int mapram_erase (struct mtd_info *mtd, struct erase_info *instr)
+{
+	/* Yeah, it's inefficient. Who cares? It's faster than a _real_
+	   flash erase. */
+	struct map_info *map = mtd->priv;
+	map_word allff;
+	unsigned long i;
+
+	allff = map_word_ff(map);
+	for (i=0; i<instr->len; i += map_bankwidth(map))
+		map_write(map, allff, instr->addr + i);
+	return 0;
+}
+
+static void mapram_nop(struct mtd_info *mtd)
+{
+	/* Nothing to see here */
+}
+
+static int __init map_ram_init(void)
+{
+	register_mtd_chip_driver(&mapram_chipdrv);
+	return 0;
+}
+
+static void __exit map_ram_exit(void)
+{
+	unregister_mtd_chip_driver(&mapram_chipdrv);
+}
+
+module_init(map_ram_init);
+module_exit(map_ram_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_DESCRIPTION("MTD chip driver for RAM chips");