Add raw NAND framework

The raw NAND framework supports SLC NAND devices.

It introduces a new high level interface (io_mtd) that
defines operations a driver can register to the NAND framework.
This interface will fill in the io_mtd device specification:
	- device_size
        - erase_size
that could be used by the io_storage interface.

NAND core source file integrates the standard read loop that
performs NAND device read operations using a skip bad block strategy.
A platform buffer must be defined in case of unaligned
data. This buffer must fit to the maximum device page size
defined by PLATFORM_MTD_MAX_PAGE_SIZE.

The raw_nand.c source file embeds the specific NAND operations
to read data.
The read command is a raw page read without any ECC correction.
This can be overridden by a low level driver.
No generic support for write or erase command or software
ECC correction.

NAND ONFI detection is available and can be enabled using
NAND_ONFI_DETECT=1.
For non-ONFI NAND management, platform can define required
information.

Change-Id: Id80e9864456cf47f02b74938cf25d99261da8e82
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Signed-off-by: Christophe Kerello <christophe.kerello@st.com>

1 files changed, 248 insertions, 0 deletions

diff --git a/drivers/io/io_mtd.c b/drivers/io/io_mtd.c
new file mode 100644
index 000000000..7575fa250
--- /dev/null
+++ b/drivers/io/io_mtd.c
@@ -0,0 +1,248 @@
+/*
+ * Copyright (c) 2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+
+#include <platform_def.h>
+
+#include <common/debug.h>
+#include <drivers/io/io_driver.h>
+#include <drivers/io/io_mtd.h>
+#include <lib/utils.h>
+
+typedef struct {
+	io_mtd_dev_spec_t	*dev_spec;
+	uintptr_t		base;
+	unsigned long long	offset;		/* Offset in bytes */
+	unsigned long long	size;	/* Size of device in bytes */
+} mtd_dev_state_t;
+
+io_type_t device_type_mtd(void);
+
+static int mtd_open(io_dev_info_t *dev_info, const uintptr_t spec,
+		    io_entity_t *entity);
+static int mtd_seek(io_entity_t *entity, int mode, signed long long offset);
+static int mtd_read(io_entity_t *entity, uintptr_t buffer, size_t length,
+		    size_t *length_read);
+static int mtd_close(io_entity_t *entity);
+static int mtd_dev_open(const uintptr_t dev_spec, io_dev_info_t **dev_info);
+static int mtd_dev_close(io_dev_info_t *dev_info);
+
+static const io_dev_connector_t mtd_dev_connector = {
+	.dev_open	= mtd_dev_open
+};
+
+static const io_dev_funcs_t mtd_dev_funcs = {
+	.type		= device_type_mtd,
+	.open		= mtd_open,
+	.seek		= mtd_seek,
+	.read		= mtd_read,
+	.close		= mtd_close,
+	.dev_close	= mtd_dev_close,
+};
+
+static mtd_dev_state_t state_pool[MAX_IO_MTD_DEVICES];
+static io_dev_info_t dev_info_pool[MAX_IO_MTD_DEVICES];
+
+io_type_t device_type_mtd(void)
+{
+	return IO_TYPE_MTD;
+}
+
+/* Locate a MTD state in the pool, specified by address */
+static int find_first_mtd_state(const io_mtd_dev_spec_t *dev_spec,
+				unsigned int *index_out)
+{
+	unsigned int index;
+	int result = -ENOENT;
+
+	for (index = 0U; index < MAX_IO_MTD_DEVICES; index++) {
+		/* dev_spec is used as identifier since it's unique */
+		if (state_pool[index].dev_spec == dev_spec) {
+			result = 0;
+			*index_out = index;
+			break;
+		}
+	}
+
+	return result;
+}
+
+/* Allocate a device info from the pool */
+static int allocate_dev_info(io_dev_info_t **dev_info)
+{
+	unsigned int index = 0U;
+	int result;
+
+	result = find_first_mtd_state(NULL, &index);
+	if (result != 0) {
+		return -ENOMEM;
+	}
+
+	dev_info_pool[index].funcs = &mtd_dev_funcs;
+	dev_info_pool[index].info = (uintptr_t)&state_pool[index];
+	*dev_info = &dev_info_pool[index];
+
+	return 0;
+}
+
+/* Release a device info from the pool */
+static int free_dev_info(io_dev_info_t *dev_info)
+{
+	int result;
+	unsigned int index = 0U;
+	mtd_dev_state_t *state;
+
+	state = (mtd_dev_state_t *)dev_info->info;
+	result = find_first_mtd_state(state->dev_spec, &index);
+	if (result != 0) {
+		return result;
+	}
+
+	zeromem(state, sizeof(mtd_dev_state_t));
+	zeromem(dev_info, sizeof(io_dev_info_t));
+
+	return 0;
+}
+
+static int mtd_open(io_dev_info_t *dev_info, const uintptr_t spec,
+		    io_entity_t *entity)
+{
+	mtd_dev_state_t *cur;
+
+	assert((dev_info->info != 0UL) && (entity->info == 0UL));
+
+	cur = (mtd_dev_state_t *)dev_info->info;
+	entity->info = (uintptr_t)cur;
+	cur->offset = 0U;
+
+	return 0;
+}
+
+/* Seek to a specific position using offset */
+static int mtd_seek(io_entity_t *entity, int mode, signed long long offset)
+{
+	mtd_dev_state_t *cur;
+
+	assert((entity->info != (uintptr_t)NULL) && (offset >= 0));
+
+	cur = (mtd_dev_state_t *)entity->info;
+
+	switch (mode) {
+	case IO_SEEK_SET:
+		if ((offset >= 0) &&
+		    ((unsigned long long)offset >= cur->size)) {
+			return -EINVAL;
+		}
+
+		cur->offset = offset;
+		break;
+	case IO_SEEK_CUR:
+		if (((cur->offset + (unsigned long long)offset) >=
+		     cur->size) ||
+		    ((cur->offset + (unsigned long long)offset) <
+		     cur->offset)) {
+			return -EINVAL;
+		}
+
+		cur->offset += (unsigned long long)offset;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int mtd_read(io_entity_t *entity, uintptr_t buffer, size_t length,
+		    size_t *out_length)
+{
+	mtd_dev_state_t *cur;
+	io_mtd_ops_t *ops;
+	int ret;
+
+	assert(entity->info != (uintptr_t)NULL);
+	assert((length > 0U) && (buffer != (uintptr_t)NULL));
+
+	cur = (mtd_dev_state_t *)entity->info;
+	ops = &cur->dev_spec->ops;
+	assert(ops->read != NULL);
+
+	VERBOSE("Read at %llx into %lx, length %zi\n",
+		cur->offset, buffer, length);
+	if ((cur->offset + length) > cur->dev_spec->device_size) {
+		return -EINVAL;
+	}
+
+	ret = ops->read(cur->offset, buffer, length, out_length);
+	if (ret < 0) {
+		return ret;
+	}
+
+	assert(*out_length == length);
+	cur->offset += *out_length;
+
+	return 0;
+}
+
+static int mtd_close(io_entity_t *entity)
+{
+	entity->info = (uintptr_t)NULL;
+
+	return 0;
+}
+
+static int mtd_dev_open(const uintptr_t dev_spec, io_dev_info_t **dev_info)
+{
+	mtd_dev_state_t *cur;
+	io_dev_info_t *info;
+	io_mtd_ops_t *ops;
+	int result;
+
+	result = allocate_dev_info(&info);
+	if (result != 0) {
+		return -ENOENT;
+	}
+
+	cur = (mtd_dev_state_t *)info->info;
+	cur->dev_spec = (io_mtd_dev_spec_t *)dev_spec;
+	*dev_info = info;
+	ops = &(cur->dev_spec->ops);
+	if (ops->init != NULL) {
+		result = ops->init(&cur->dev_spec->device_size,
+				   &cur->dev_spec->erase_size);
+	}
+
+	if (result == 0) {
+		cur->size = cur->dev_spec->device_size;
+	} else {
+		cur->size = 0ULL;
+	}
+
+	return result;
+}
+
+static int mtd_dev_close(io_dev_info_t *dev_info)
+{
+	return free_dev_info(dev_info);
+}
+
+/* Exported functions */
+
+/* Register the MTD driver in the IO abstraction */
+int register_io_dev_mtd(const io_dev_connector_t **dev_con)
+{
+	int result;
+
+	result = io_register_device(&dev_info_pool[0]);
+	if (result == 0) {
+		*dev_con = &mtd_dev_connector;
+	}
+
+	return result;
+}