API for external applications.

This is an API for external (standalone) applications running on top of
U-Boot, and is meant to be more extensible and robust than the existing
jumptable mechanism. It is similar to UNIX syscall approach. See api/README
for more details.

Included is the demo application using this new framework (api_examples).

Please note this is still an experimental feature, and is turned off by
default.

Signed-off-by: Rafal Jaworowski <raj@semihalf.com>

1 files changed, 370 insertions, 0 deletions

diff --git a/api/api_storage.c b/api/api_storage.c
new file mode 100644
index 0000000..7cd4efb
--- /dev/null
+++ b/api/api_storage.c
@@ -0,0 +1,370 @@
+/*
+ * (C) Copyright 2007 Semihalf
+ *
+ * Written by: Rafal Jaworowski <raj@semihalf.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ */
+
+#include <config.h>
+
+#if defined(CONFIG_API)
+
+#include <common.h>
+#include <api_public.h>
+
+#define DEBUG
+#undef DEBUG
+
+#ifdef DEBUG
+#define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt, ##args); } while (0)
+#else
+#define debugf(fmt, args...)
+#endif
+
+#define errf(fmt, args...) do { printf("ERROR @ %s(): ", __func__); printf(fmt, ##args); } while (0)
+
+
+#define ENUM_IDE	0
+#define ENUM_USB	1
+#define ENUM_SCSI	2
+#define ENUM_MMC	3
+#define ENUM_MAX	4
+
+struct stor_spec {
+	int		max_dev;
+	int		enum_started;
+	int		enum_ended;
+	int		type;		/* "external" type: DT_STOR_{IDE,USB,etc} */
+	char		name[4];
+};
+
+static struct stor_spec specs[ENUM_MAX] = { { 0, 0, 0, 0, "" }, };
+
+
+void dev_stor_init(void)
+{
+#if (CONFIG_COMMANDS & CFG_CMD_IDE)
+	specs[ENUM_IDE].max_dev = CFG_IDE_MAXDEVICE;
+	specs[ENUM_IDE].enum_started = 0;
+	specs[ENUM_IDE].enum_ended = 0;
+	specs[ENUM_IDE].type = DEV_TYP_STOR | DT_STOR_IDE;
+	specs[ENUM_IDE].name = "ide";
+#endif
+#if (CONFIG_COMMANDS & CFG_CMD_USB)
+	specs[ENUM_USB].max_dev = USB_MAX_STOR_DEV;
+	specs[ENUM_USB].enum_started = 0;
+	specs[ENUM_USB].enum_ended = 0;
+	specs[ENUM_USB].type = DEV_TYP_STOR | DT_STOR_USB;
+	specs[ENUM_USB].name = "usb";
+#endif
+#if (CONFIG_COMMANDS & CFG_CMD_SCSI)
+	specs[ENUM_SCSI].max_dev = CFG_SCSI_MAX_DEVICE;
+	specs[ENUM_SCSI].enum_started = 0;
+	specs[ENUM_SCSI].enum_ended = 0;
+	specs[ENUM_SCSI].type = DEV_TYP_STOR | DT_STOR_SCSI;
+	specs[ENUM_SCSI].name = "scsi";
+#endif
+}
+
+/*
+ * Finds next available device in the storage group
+ *
+ * type:	storage group type - ENUM_IDE, ENUM_SCSI etc.
+ *
+ * first:	if 1 the first device in the storage group is returned (if
+ *              exists), if 0 the next available device is searched
+ *
+ * more:	returns 0/1 depending if there are more devices in this group
+ *		available (for future iterations)
+ *
+ * returns:	0/1 depending if device found in this iteration
+ */
+static int dev_stor_get(int type, int first, int *more, struct device_info *di)
+{
+	int found = 0;
+	*more = 0;
+
+	int i;
+
+	block_dev_desc_t *dd;
+
+	if (first) {
+		di->cookie = (void *)get_dev(specs[type].name, 0);
+		found = 1;
+
+	} else {
+		for (i = 0; i < specs[type].max_dev; i++)
+			if (di->cookie == (void *)get_dev(specs[type].name, i)) {
+				/* previous cookie found -- advance to the
+				 * next device, if possible */
+
+				if (++i >= specs[type].max_dev) {
+					/* out of range, no more to enum */
+					di->cookie = NULL;
+					break;
+				}
+
+				di->cookie = (void *)get_dev(specs[type].name, i);
+				found = 1;
+
+				/* provide hint if there are more devices in
+				 * this group to enumerate */
+				if ((i + 1) < specs[type].max_dev)
+					*more = 1;
+
+				break;
+			}
+	}
+
+	if (found) {
+		di->type = specs[type].type;
+
+		if (di->cookie != NULL) {
+			dd = (block_dev_desc_t *)di->cookie;
+			if (dd->type == DEV_TYPE_UNKNOWN) {
+				debugf("device instance exists, but is not active..");
+				found = 0;
+			} else {
+				di->di_stor.block_count = dd->lba;
+				di->di_stor.block_size = dd->blksz;
+			}
+		}
+
+	} else
+		di->cookie = NULL;
+
+	return found;
+}
+
+
+/*
+ * returns:	ENUM_IDE, ENUM_USB etc. based on block_dev_desc_t
+ */
+static int dev_stor_type(block_dev_desc_t *dd)
+{
+	int i, j;
+
+	for (i = ENUM_IDE; i < ENUM_MAX; i++)
+		for (j = 0; j < specs[i].max_dev; j++)
+			if (dd == get_dev(specs[i].name, j))
+				return i;
+
+	return ENUM_MAX;
+}
+
+
+/*
+ * returns:	0/1 whether cookie points to some device in this group
+ */
+static int dev_is_stor(int type, struct device_info *di)
+{
+	return (dev_stor_type(di->cookie) == type) ? 1 : 0;
+}
+
+
+static int dev_enum_stor(int type, struct device_info *di)
+{
+	int found = 0, more = 0;
+
+	debugf("called, type %d\n", type);
+
+	/*
+	 * Formulae for enumerating storage devices:
+	 * 1. if cookie (hint from previous enum call) is NULL we start again
+	 *    with enumeration, so return the first available device, done.
+	 *
+	 * 2. if cookie is not NULL, check if it identifies some device in
+	 *    this group:
+	 *
+	 * 2a. if cookie is a storage device from our group (IDE, USB etc.),
+	 *     return next available (if exists) in this group
+	 *
+	 * 2b. if it isn't device from our group, check if such devices were
+	 *     ever enumerated before:
+	 *     - if not, return the first available device from this group
+	 *     - else return 0
+	 */
+
+	if (di->cookie == NULL) {
+
+		debugf("group%d - enum restart\n", type);
+
+		/*
+		 * 1. Enumeration (re-)started: take the first available
+		 * device, if exists
+		 */
+		found = dev_stor_get(type, 1, &more, di);
+		specs[type].enum_started = 1;
+
+	} else if (dev_is_stor(type, di)) {
+
+		debugf("group%d - enum continued for the next device\n", type);
+
+		if (specs[type].enum_ended) {
+			debugf("group%d - nothing more to enum!\n", type);
+			return 0;
+		}
+
+		/* 2a. Attempt to take a next available device in the group */
+		found = dev_stor_get(type, 0, &more, di);
+
+	} else {
+
+		if (specs[type].enum_ended) {
+			debugf("group %d - already enumerated, skipping\n", type);
+			return 0;
+		}
+
+		debugf("group%d - first time enum\n", type);
+
+		if (specs[type].enum_started == 0) {
+			/*
+			 * 2b.  If enumerating devices in this group did not
+			 * happen before, it means the cookie pointed to a
+			 * device frome some other group (another storage
+			 * group, or network); in this case try to take the
+			 * first available device from our group
+			 */
+			specs[type].enum_started = 1;
+
+			/*
+			 * Attempt to take the first device in this group:
+			 *'first element' flag is set
+			 */
+			found = dev_stor_get(type, 1, &more, di);
+
+		} else {
+			errf("group%d - out of order iteration\n", type);
+			found = 0;
+			more = 0;
+		}
+	}
+
+	/*
+	 * If there are no more devices in this group, consider its
+	 * enumeration finished
+	 */
+	specs[type].enum_ended = (!more) ? 1 : 0;
+
+	if (found)
+		debugf("device found, returning cookie 0x%08x\n",
+			(u_int32_t)di->cookie);
+	else
+		debugf("no device found\n");
+
+	return found;
+}
+
+void dev_enum_reset(void)
+{
+	int i;
+
+	for (i = 0; i < ENUM_MAX; i ++) {
+		specs[i].enum_started = 0;
+		specs[i].enum_ended = 0;
+	}
+}
+
+int dev_enum_storage(struct device_info *di)
+{
+	int i;
+
+	/*
+	 * check: ide, usb, scsi, mmc
+	 */
+	for (i = ENUM_IDE; i < ENUM_MAX; i ++) {
+		if (dev_enum_stor(i, di))
+			return 1;
+	}
+
+	return 0;
+}
+
+static int dev_stor_is_valid(int type, block_dev_desc_t *dd)
+{
+	int i;
+
+	for (i = 0; i < specs[type].max_dev; i++)
+		if (dd == get_dev(specs[type].name, i))
+			if (dd->type != DEV_TYPE_UNKNOWN)
+				return 1;
+
+	return 0;
+}
+
+
+int dev_open_stor(void *cookie)
+{
+	int type = dev_stor_type(cookie);
+
+	if (type == ENUM_MAX)
+		return API_ENODEV;
+
+	if (dev_stor_is_valid(type, (block_dev_desc_t *)cookie))
+		return 0;
+
+	return API_ENODEV;
+}
+
+
+int dev_close_stor(void *cookie)
+{
+	/*
+	 * Not much to do as we actually do not alter storage devices upon
+	 * close
+	 */
+	return 0;
+}
+
+
+static int dev_stor_index(block_dev_desc_t *dd)
+{
+	int i, type;
+
+	type = dev_stor_type(dd);
+	for (i = 0; i < specs[type].max_dev; i++)
+		if (dd == get_dev(specs[type].name, i))
+			return i;
+
+	return (specs[type].max_dev);
+}
+
+
+lbasize_t dev_read_stor(void *cookie, void *buf, lbasize_t len, lbastart_t start)
+{
+	int type;
+	block_dev_desc_t *dd = (block_dev_desc_t *)cookie;
+
+	if ((type = dev_stor_type(dd)) == ENUM_MAX)
+		return 0;
+
+	if (!dev_stor_is_valid(type, dd))
+		return 0;
+
+	if ((dd->block_read) == NULL) {
+		debugf("no block_read() for device 0x%08x\n");
+		return 0;
+	}
+
+	return (dd->block_read(dev_stor_index(dd), start, len, buf));
+}
+
+#endif /* CONFIG_API */