From 500856eb1707ed17d9204baa61dd59948d3b2899 Mon Sep 17 00:00:00 2001 From: Rafal Jaworowski Date: Wed, 9 Jan 2008 19:39:36 +0100 Subject: 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 --- api/api_storage.c | 370 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 370 insertions(+) create mode 100644 api/api_storage.c (limited to 'api/api_storage.c') diff --git a/api/api_storage.c b/api/api_storage.c new file mode 100644 index 0000000000..7cd4efb45b --- /dev/null +++ b/api/api_storage.c @@ -0,0 +1,370 @@ +/* + * (C) Copyright 2007 Semihalf + * + * Written by: Rafal Jaworowski + * + * 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 + +#if defined(CONFIG_API) + +#include +#include + +#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 */ -- cgit v1.2.3