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.c | 670 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 670 insertions(+) create mode 100644 api/api.c (limited to 'api/api.c') diff --git a/api/api.c b/api/api.c new file mode 100644 index 0000000000..10f83eb691 --- /dev/null +++ b/api/api.c @@ -0,0 +1,670 @@ +/* + * (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 +#include +#include +#include + +#include "api_private.h" + +#define DEBUG +#undef DEBUG + +/* U-Boot routines needed */ +extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]); +extern uchar (*env_get_char)(int); +extern uchar *env_get_addr(int); + +/***************************************************************************** + * + * This is the API core. + * + * API_ functions are part of U-Boot code and constitute the lowest level + * calls: + * + * - they know what values they need as arguments + * - their direct return value pertains to the API_ "shell" itself (0 on + * success, some error code otherwise) + * - if the call returns a value it is buried within arguments + * + ****************************************************************************/ + +#ifdef DEBUG +#define debugf(fmt, args...) do { printf("%s(): ", __func__); printf(fmt, ##args); } while (0) +#else +#define debugf(fmt, args...) +#endif + +typedef int (*cfp_t)(va_list argp); + +static int calls_no; + +/* + * pseudo signature: + * + * int API_getc(int *c) + */ +static int API_getc(va_list ap) +{ + int *c; + + if ((c = (int *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + *c = getc(); + return 0; +} + +/* + * pseudo signature: + * + * int API_tstc(int *c) + */ +static int API_tstc(va_list ap) +{ + int *t; + + if ((t = (int *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + *t = tstc(); + return 0; +} + +/* + * pseudo signature: + * + * int API_putc(char *ch) + */ +static int API_putc(va_list ap) +{ + char *c; + + if ((c = (char *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + putc(*c); + return 0; +} + +/* + * pseudo signature: + * + * int API_puts(char **s) + */ +static int API_puts(va_list ap) +{ + char *s; + + if ((s = (char *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + puts(s); + return 0; +} + +/* + * pseudo signature: + * + * int API_reset(void) + */ +static int API_reset(va_list ap) +{ + do_reset(NULL, 0, 0, NULL); + + /* NOT REACHED */ + return 0; +} + +/* + * pseudo signature: + * + * int API_get_sys_info(struct sys_info *si) + * + * fill out the sys_info struct containing selected parameters about the + * machine + */ +static int API_get_sys_info(va_list ap) +{ + struct sys_info *si; + + si = (struct sys_info *)va_arg(ap, u_int32_t); + if (si == NULL) + return API_ENOMEM; + + return (platform_sys_info(si)) ? 0 : API_ENODEV; +} + +/* + * pseudo signature: + * + * int API_udelay(unsigned long *udelay) + */ +static int API_udelay(va_list ap) +{ + unsigned long *d; + + if ((d = (unsigned long *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + udelay(*d); + return 0; +} + +/* + * pseudo signature: + * + * int API_get_timer(unsigned long *current, unsigned long *base) + */ +static int API_get_timer(va_list ap) +{ + unsigned long *base, *cur; + + cur = (unsigned long *)va_arg(ap, u_int32_t); + if (cur == NULL) + return API_EINVAL; + + base = (unsigned long *)va_arg(ap, u_int32_t); + if (base == NULL) + return API_EINVAL; + + *cur = get_timer(*base); + return 0; +} + + +/***************************************************************************** + * + * pseudo signature: + * + * int API_dev_enum(struct device_info *) + * + * + * cookies uniqely identify the previously enumerated device instance and + * provide a hint for what to inspect in current enum iteration: + * + * - net: ð_device struct address from list pointed to by eth_devices + * + * - storage: block_dev_desc_t struct address from &ide_dev_desc[n], + * &scsi_dev_desc[n] and similar tables + * + ****************************************************************************/ + +static int API_dev_enum(va_list ap) +{ + struct device_info *di; + + /* arg is ptr to the device_info struct we are going to fill out */ + di = (struct device_info *)va_arg(ap, u_int32_t); + if (di == NULL) + return API_EINVAL; + + if (di->cookie == NULL) { + /* start over - clean up enumeration */ + dev_enum_reset(); /* XXX shouldn't the name contain 'stor'? */ + debugf("RESTART ENUM\n"); + + /* net device enumeration first */ + if (dev_enum_net(di)) + return 0; + } + + /* + * The hidden assumption is there can only be one active network + * device and it is identified upon enumeration (re)start, so there's + * no point in trying to find network devices in other cases than the + * (re)start and hence the 'next' device can only be storage + */ + if (!dev_enum_storage(di)) + /* make sure we mark there are no more devices */ + di->cookie = NULL; + + return 0; +} + + +static int API_dev_open(va_list ap) +{ + struct device_info *di; + int err = 0; + + /* arg is ptr to the device_info struct */ + di = (struct device_info *)va_arg(ap, u_int32_t); + if (di == NULL) + return API_EINVAL; + + /* Allow only one consumer of the device at a time */ + if (di->state == DEV_STA_OPEN) + return API_EBUSY; + + if (di->cookie == NULL) + return API_ENODEV; + + if (di->type & DEV_TYP_STOR) + err = dev_open_stor(di->cookie); + + else if (di->type & DEV_TYP_NET) + err = dev_open_net(di->cookie); + else + err = API_ENODEV; + + if (!err) + di->state = DEV_STA_OPEN; + + return err; +} + + +static int API_dev_close(va_list ap) +{ + struct device_info *di; + int err = 0; + + /* arg is ptr to the device_info struct */ + di = (struct device_info *)va_arg(ap, u_int32_t); + if (di == NULL) + return API_EINVAL; + + if (di->state == DEV_STA_CLOSED) + return 0; + + if (di->cookie == NULL) + return API_ENODEV; + + if (di->type & DEV_TYP_STOR) + err = dev_close_stor(di->cookie); + + else if (di->type & DEV_TYP_NET) + err = dev_close_net(di->cookie); + else + /* + * In case of unknown device we cannot change its state, so + * only return error code + */ + err = API_ENODEV; + + if (!err) + di->state = DEV_STA_CLOSED; + + return err; +} + + +/* + * Notice: this is for sending network packets only, as U-Boot does not + * support writing to storage at the moment (12.2007) + * + * pseudo signature: + * + * int API_dev_write( + * struct device_info *di, + * void *buf, + * int *len + * ) + * + * buf: ptr to buffer from where to get the data to send + * + * len: length of packet to be sent (in bytes) + * + */ +static int API_dev_write(va_list ap) +{ + struct device_info *di; + void *buf; + int *len; + int err = 0; + + /* 1. arg is ptr to the device_info struct */ + di = (struct device_info *)va_arg(ap, u_int32_t); + if (di == NULL) + return API_EINVAL; + + /* XXX should we check if device is open? i.e. the ->state ? */ + + if (di->cookie == NULL) + return API_ENODEV; + + /* 2. arg is ptr to buffer from where to get data to write */ + buf = (void *)va_arg(ap, u_int32_t); + if (buf == NULL) + return API_EINVAL; + + /* 3. arg is length of buffer */ + len = (int *)va_arg(ap, u_int32_t); + if (len == NULL) + return API_EINVAL; + if (*len <= 0) + return API_EINVAL; + + if (di->type & DEV_TYP_STOR) + /* + * write to storage is currently not supported by U-Boot: + * no storage device implements block_write() method + */ + return API_ENODEV; + + else if (di->type & DEV_TYP_NET) + err = dev_write_net(di->cookie, buf, *len); + else + err = API_ENODEV; + + return err; +} + + +/* + * pseudo signature: + * + * int API_dev_read( + * struct device_info *di, + * void *buf, + * size_t *len, + * unsigned long *start + * size_t *act_len + * ) + * + * buf: ptr to buffer where to put the read data + * + * len: ptr to length to be read + * - network: len of packet to read (in bytes) + * - storage: # of blocks to read (can vary in size depending on define) + * + * start: ptr to start block (only used for storage devices, ignored for + * network) + * + * act_len: ptr to where to put the len actually read + */ +static int API_dev_read(va_list ap) +{ + struct device_info *di; + void *buf; + lbasize_t *len_stor, *act_len_stor; + lbastart_t *start; + int *len_net, *act_len_net; + + /* 1. arg is ptr to the device_info struct */ + di = (struct device_info *)va_arg(ap, u_int32_t); + if (di == NULL) + return API_EINVAL; + + /* XXX should we check if device is open? i.e. the ->state ? */ + + if (di->cookie == NULL) + return API_ENODEV; + + /* 2. arg is ptr to buffer from where to put the read data */ + buf = (void *)va_arg(ap, u_int32_t); + if (buf == NULL) + return API_EINVAL; + + if (di->type & DEV_TYP_STOR) { + /* 3. arg - ptr to var with # of blocks to read */ + len_stor = (lbasize_t *)va_arg(ap, u_int32_t); + if (!len_stor) + return API_EINVAL; + if (*len_stor <= 0) + return API_EINVAL; + + /* 4. arg - ptr to var with start block */ + start = (lbastart_t *)va_arg(ap, u_int32_t); + + /* 5. arg - ptr to var where to put the len actually read */ + act_len_stor = (lbasize_t *)va_arg(ap, u_int32_t); + if (!act_len_stor) + return API_EINVAL; + + *act_len_stor = dev_read_stor(di->cookie, buf, *len_stor, *start); + + } else if (di->type & DEV_TYP_NET) { + + /* 3. arg points to the var with length of packet to read */ + len_net = (int *)va_arg(ap, u_int32_t); + if (!len_net) + return API_EINVAL; + if (*len_net <= 0) + return API_EINVAL; + + /* 4. - ptr to var where to put the len actually read */ + act_len_net = (int *)va_arg(ap, u_int32_t); + if (!act_len_net) + return API_EINVAL; + + *act_len_net = dev_read_net(di->cookie, buf, *len_net); + + } else + return API_ENODEV; + + return 0; +} + + +/* + * pseudo signature: + * + * int API_env_get(const char *name, char **value) + * + * name: ptr to name of env var + */ +static int API_env_get(va_list ap) +{ + char *name, **value; + + if ((name = (char *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + if ((value = (char **)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + *value = getenv(name); + + return 0; +} + +/* + * pseudo signature: + * + * int API_env_set(const char *name, const char *value) + * + * name: ptr to name of env var + * + * value: ptr to value to be set + */ +static int API_env_set(va_list ap) +{ + char *name, *value; + + if ((name = (char *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + if ((value = (char *)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + setenv(name, value); + + return 0; +} + +/* + * pseudo signature: + * + * int API_env_enum(const char *last, char **next) + * + * last: ptr to name of env var found in last iteration + */ +static int API_env_enum(va_list ap) +{ + int i, n; + char *last, **next; + + last = (char *)va_arg(ap, u_int32_t); + + if ((next = (char **)va_arg(ap, u_int32_t)) == NULL) + return API_EINVAL; + + if (last == NULL) + /* start over */ + *next = ((char *)env_get_addr(0)); + else { + *next = last; + + for (i = 0; env_get_char(i) != '\0'; i = n + 1) { + for (n = i; env_get_char(n) != '\0'; ++n) { + if (n >= CFG_ENV_SIZE) { + /* XXX shouldn't we set *next = NULL?? */ + return 0; + } + } + + if (envmatch((uchar *)last, i) < 0) + continue; + + /* try to get next name */ + i = n + 1; + if (env_get_char(i) == '\0') { + /* no more left */ + *next = NULL; + return 0; + } + + *next = ((char *)env_get_addr(i)); + return 0; + } + } + + return 0; +} + +static cfp_t calls_table[API_MAXCALL] = { NULL, }; + +/* + * The main syscall entry point - this is not reentrant, only one call is + * serviced until finished. + * + * e.g. syscall(1, int *, u_int32_t, u_int32_t, u_int32_t, u_int32_t); + * + * call: syscall number + * + * retval: points to the return value placeholder, this is the place the + * syscall puts its return value, if NULL the caller does not + * expect a return value + * + * ... syscall arguments (variable number) + * + * returns: 0 if the call not found, 1 if serviced + */ +int syscall(int call, int *retval, ...) +{ + va_list ap; + int rv; + + if (call < 0 || call >= calls_no || calls_table[call] == NULL) { + debugf("invalid call #%d\n", call); + return 0; + } + + if (calls_table[call] == NULL) { + debugf("syscall #%d does not have a handler\n", call); + return 0; + } + + va_start(ap, retval); + rv = calls_table[call](ap); + if (retval != NULL) + *retval = rv; + + return 1; +} + +void api_init(void) +{ + struct api_signature *sig = NULL; + + /* TODO put this into linker set one day... */ + calls_table[API_RSVD] = NULL; + calls_table[API_GETC] = &API_getc; + calls_table[API_PUTC] = &API_putc; + calls_table[API_TSTC] = &API_tstc; + calls_table[API_PUTS] = &API_puts; + calls_table[API_RESET] = &API_reset; + calls_table[API_GET_SYS_INFO] = &API_get_sys_info; + calls_table[API_UDELAY] = &API_udelay; + calls_table[API_GET_TIMER] = &API_get_timer; + calls_table[API_DEV_ENUM] = &API_dev_enum; + calls_table[API_DEV_OPEN] = &API_dev_open; + calls_table[API_DEV_CLOSE] = &API_dev_close; + calls_table[API_DEV_READ] = &API_dev_read; + calls_table[API_DEV_WRITE] = &API_dev_write; + calls_table[API_ENV_GET] = &API_env_get; + calls_table[API_ENV_SET] = &API_env_set; + calls_table[API_ENV_ENUM] = &API_env_enum; + calls_no = API_MAXCALL; + + debugf("API initialized with %d calls\n", calls_no); + + dev_stor_init(); + + /* + * Produce the signature so the API consumers can find it + */ + sig = malloc(sizeof(struct api_signature)); + if (sig == NULL) { + printf("API: could not allocate memory for the signature!\n"); + return; + } + + debugf("API sig @ 0x%08x\n", sig); + memcpy(sig->magic, API_SIG_MAGIC, 8); + sig->version = API_SIG_VERSION; + sig->syscall = &syscall; + sig->checksum = 0; + sig->checksum = crc32(0, (unsigned char *)sig, + sizeof(struct api_signature)); + debugf("syscall entry: 0x%08x\n", sig->syscall); +} + +void platform_set_mr(struct sys_info *si, unsigned long start, unsigned long size, + int flags) +{ + int i; + + if (!si->mr || !size || (flags == 0)) + return; + + /* find free slot */ + for (i = 0; i < si->mr_no; i++) + if (si->mr[i].flags == 0) { + /* insert new mem region */ + si->mr[i].start = start; + si->mr[i].size = size; + si->mr[i].flags = flags; + return; + } +} + +#endif /* CONFIG_API */ -- cgit v1.2.1