/****************************************************************************** ** ** FILE NAME : ifxmips_rcu.c ** PROJECT : UEIP ** MODULES : RCU (Reset Control Unit) ** ** DATE : 17 Jun 2009 ** AUTHOR : Xu Liang ** DESCRIPTION : RCU driver common source file ** COPYRIGHT : Copyright (c) 2006 ** Infineon Technologies AG ** Am Campeon 1-12, 85579 Neubiberg, Germany ** ** 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. ** ** HISTORY ** $Date $Author $Comment ** 17 JUN 2009 Xu Liang Init Version *******************************************************************************/ /*! \file ifxmips_rcu.c \ingroup IFX_RCU \brief RCU driver main source file. */ /* * #################################### * Version No. * #################################### */ #define IFX_RCU_VER_MAJOR 1 #define IFX_RCU_VER_MID 0 #define IFX_RCU_VER_MINOR 6 /* * #################################### * Head File * #################################### */ /* * Common Head File */ #include #include #include #include #include #include #include //#include //#include #include /* * Chip Specific Head File */ #include #include #include #include "ifxmips_rcu.h" /* * #################################### * Definition * #################################### */ /* * #################################### * Declaration * #################################### */ /* * File Operations */ static int ifx_rcu_open(struct inode *inode, struct file *filep); static int ifx_rcu_release(struct inode *inode, struct file *filelp); static int ifx_rcu_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg); /* * Proc File Functions */ static inline void proc_file_create(void); static inline void proc_file_delete(void); static int proc_read_version(char *, char **, off_t, int, int *, void *); static int proc_read_domain(char *, char **, off_t, int, int *, void *); /* * Proc Help Functions */ static inline int print_reset_domain(char *, int); static inline int print_reset_handler(char *, int, ifx_rcu_handler_t *); /* * Init Help Functions */ static inline int ifx_rcu_version(char *); /* * #################################### * Local Variable * #################################### */ spinlock_t g_rcu_lock; // must be locked before g_rcu_register_lock locked // and be released after g_rcu_register_lock released spinlock_t g_rcu_register_lock; // use spinlock rather than semaphore or mutex // because most functions run in user context // and they do not take much time to finish operation static IFX_RCU_DECLARE_DOMAIN_NAME(g_rcu_domain_name); static IFX_RCU_DECLARE_MODULE_NAME(g_rcu_module_name); static struct file_operations g_rcu_fops = { .open = ifx_rcu_open, .release = ifx_rcu_release, .ioctl = ifx_rcu_ioctl }; static unsigned int g_dbg_enable = DBG_ENABLE_MASK_ERR; static struct proc_dir_entry* g_rcu_dir = NULL; /* * #################################### * Local Function * #################################### */ static int ifx_rcu_open(struct inode *inode, struct file *filep) { return IFX_SUCCESS; } static int ifx_rcu_release(struct inode *inode, struct file *filelp) { return IFX_SUCCESS; } static int ifx_rcu_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg) { int ret; // check magic number if ( _IOC_TYPE(cmd) != IFX_RCU_IOC_MAGIC ) return IFX_ERROR; // check read/write right if ( ((_IOC_DIR(cmd) & _IOC_WRITE) && !access_ok(VERIFY_READ, arg, _IOC_SIZE(cmd))) || ((_IOC_DIR (cmd) & _IOC_READ) && !access_ok(VERIFY_WRITE, arg, _IOC_SIZE(cmd))) ) return IFX_ERROR; switch (cmd) { case IFX_RCU_IOC_VERSION: { struct ifx_rcu_ioctl_version version = { .major = IFX_RCU_VER_MAJOR, .mid = IFX_RCU_VER_MID, .minor = IFX_RCU_VER_MINOR }; ret = copy_to_user((void *)arg, (void *)&version, sizeof(version)); } break; case IFX_RCU_IOC_QUERY_RST_DOMAIN: { struct ifx_rcu_ioctl_query_rst_domain query = {0}; ret = copy_from_user((void *)&query, (void *)arg, sizeof(query)); if ( ret == IFX_SUCCESS ) { if ( query.domain_id < NUM_ENTITY(g_rcu_domains) ) { query.f_reset = ifx_rcu_stat_get(query.domain_id); ret = copy_to_user((void *)arg, (void *)&query, sizeof(query)); } else ret = IFX_ERROR; } } break; default: ret = IFX_ERROR; } return ret; } static inline void proc_file_create(void) { g_rcu_dir = proc_mkdir("driver/ifx_rcu", NULL); create_proc_read_entry("version", 0, g_rcu_dir, proc_read_version, NULL); create_proc_read_entry("domain", 0, g_rcu_dir, proc_read_domain, NULL); } static inline void proc_file_delete(void) { remove_proc_entry("domain", g_rcu_dir); remove_proc_entry("version", g_rcu_dir); remove_proc_entry("driver/ifx_rcu", NULL); } static int proc_read_version(char *buf, char **start, off_t offset, int count, int *eof, void *data) { int len = 0; len += ifx_rcu_version(buf + len); if ( offset >= len ) { *start = buf; *eof = 1; return 0; } *start = buf + offset; if ( (len -= offset) > count ) return count; *eof = 1; return len; } char proc_read_str[2048]; static int proc_read_domain(char *page, char **start, off_t off, int count, int *eof, void *data) { int len = 0; int len_max = off + count; char *pstr; int llen; int i, j; ifx_rcu_handler_t *p_handler; pstr = *start = page; for ( i = 0; i < NUM_ENTITY(g_rcu_domains); i++ ) { llen = print_reset_domain(proc_read_str, i); if ( len <= off && len + llen > off ) { memcpy(pstr, proc_read_str + off - len, len + llen - off); pstr += len + llen - off; } else if ( len > off ) { memcpy(pstr, proc_read_str, llen); pstr += llen; } len += llen; if ( len >= len_max ) goto PROC_READ_DOMAIN_OVERRUN_END; for ( j = 1, p_handler = g_rcu_domains[i].handlers; p_handler != NULL; j++, p_handler = p_handler->next ) { llen = print_reset_handler(proc_read_str, j, p_handler); if ( len <= off && len + llen > off ) { memcpy(pstr, proc_read_str + off - len, len + llen - off); pstr += len + llen - off; } else if ( len > off ) { memcpy(pstr, proc_read_str, llen); pstr += llen; } len += llen; if ( len >= len_max ) goto PROC_READ_DOMAIN_OVERRUN_END; } } *eof = 1; return len - off; PROC_READ_DOMAIN_OVERRUN_END: return len - llen - off; } static inline int print_reset_domain(char *buf, int i) { int len = 0; unsigned int domain_id_bits; int domain_id; int flag; len += sprintf(buf + len, "Reset Domain - %s\n", g_rcu_domain_name[i]); flag = 0; domain_id_bits = g_rcu_domains[i].affected_domains & ~(1 << i); while ( domain_id_bits != 0 ) { domain_id = clz(domain_id_bits); domain_id_bits ^= 1 << domain_id; if ( !flag ) { len += sprintf(buf + len, " affected domains: %s", g_rcu_domain_name[domain_id]); flag++; } else len += sprintf(buf + len, ", %s", g_rcu_domain_name[domain_id]); if ( domain_id_bits == 0 ) len += sprintf(buf + len, "\n"); } len += sprintf(buf + len, " rst_req_value - %#08x, rst_req_mask - %#08x, rst_stat_mask - %#08x\n", g_rcu_domains[i].rst_req_value, g_rcu_domains[i].rst_req_mask, g_rcu_domains[i].rst_stat_mask); if ( g_rcu_domains[i].latch ) len += sprintf(buf + len, " latch mode, udelay - %d\n", g_rcu_domains[i].udelay); else len += sprintf(buf + len, " pulse mode\n"); if ( g_rcu_domains[i].handlers ) len += sprintf(buf + len, " handlers:\n"); else len += sprintf(buf + len, " handlers: NULL\n"); return len; } static inline int print_reset_handler(char *buf, int i, ifx_rcu_handler_t *handler) { int len = 0; const char *name = NULL; #if defined(CONFIG_KALLSYMS) unsigned long offset, size; char *modname; char namebuf[KSYM_NAME_LEN+1]; #endif #if defined(CONFIG_KALLSYMS) name = kallsyms_lookup((unsigned long)handler->fn, &size, &offset, &modname, namebuf); #endif len += sprintf(buf + len, " %d. next - %#08x\n", i, (unsigned int)handler->next); if ( name != NULL ) len += sprintf(buf + len, " fn - %s (%#08x)\n", name, (unsigned int)handler->fn); else len += sprintf(buf + len, " fn - %#08x\n", (unsigned int)handler->fn); len += sprintf(buf + len, " arg - %#08lx\n", handler->arg); len += sprintf(buf + len, " module - %s\n", g_rcu_module_name[handler->module_id]); return len; } static inline int ifx_rcu_version(char *buf) { return sprintf(buf, "Infineon Technologies RCU driver version %d.%d.%d \n", IFX_RCU_VER_MAJOR, IFX_RCU_VER_MID, IFX_RCU_VER_MINOR); } /* * #################################### * Global Function * #################################### */ /*! \fn unsigned int ifx_rcu_rst_req_read(void) \brief Read register "IFX_RCU_RST_REQ" to get reset status. This function provide direct access to register "IFX_RCU_RST_REQ" for status query. Protection for multiple access is provided in this function. \return unsigned int - value of register "IFX_RCU_RST_REQ" \ingroup IFX_RCU_API */ unsigned int ifx_rcu_rst_req_read(void) { unsigned long sys_flags; unsigned int ret; spin_lock_irqsave(&g_rcu_register_lock, sys_flags); ret = IFX_REG_R32(IFX_RCU_RST_REQ); spin_unlock_irqrestore(&g_rcu_register_lock, sys_flags); return ret; } EXPORT_SYMBOL(ifx_rcu_rst_req_read); /*! \fn void ifx_rcu_rst_req_write(unsigned int value, unsigned int mask) \brief Write register "IFX_RCU_RST_REQ" to reset individual hardware module. This function provide direct access to register "IFX_RCU_RST_REQ" for reseting individual hardware module. Protection for multiple access is provided in this function. \param value - unsigned int, each bit stands for one hardware module \param mask - usnigned int, value AND mask before writing to register \ingroup IFX_RCU_API */ void ifx_rcu_rst_req_write(unsigned int value, unsigned int mask) { unsigned long sys_flags; spin_lock_irqsave(&g_rcu_register_lock, sys_flags); IFX_REG_W32_MASK(mask, value & mask, IFX_RCU_RST_REQ); spin_unlock_irqrestore(&g_rcu_register_lock, sys_flags); } EXPORT_SYMBOL(ifx_rcu_rst_req_write); /*! \fn unsigned int ifx_rcu_rst_stat_read(void) \brief Read register "IFX_RCU_RST_STAT" to get reset status. This function provide direct access to register "IFX_RCU_RST_STAT" for status query. Protection for multiple access is provided in this function. \return unsigned int - value of register "IFX_RCU_RST_STAT" \ingroup IFX_RCU_API */ unsigned int ifx_rcu_rst_stat_read(void) { unsigned long sys_flags; unsigned int ret; spin_lock_irqsave(&g_rcu_register_lock, sys_flags); ret = IFX_REG_R32(IFX_RCU_RST_STAT); spin_unlock_irqrestore(&g_rcu_register_lock, sys_flags); return ret; } EXPORT_SYMBOL(ifx_rcu_rst_stat_read); /*! \fn int ifx_rcu_request(unsigned int reset_domain_id, unsigned int module_id, ifx_rcu_callbackfn callbackfn, unsigned long arg) \brief Register ownership of one hardware module. User uses this function to register ownership of one hardware module and register callback function to receive reset event. When reset is triggered by other component, one pre-reset event is received through callback function before reset, and one post-reset event is received through callback function after reset. \param reset_domain_id - unsigned int, hardware module ID \param module_id - unsigned int, driver/component module ID \param callbackfn - ifx_rcu_callbackfn, callback function to receive event \param arg - unsigned long, parameter of callback function \return IFX_SUCCESS Register successfully. \return IFX_ERROR Register fail. \ingroup IFX_RCU_API */ int ifx_rcu_request(unsigned int reset_domain_id, unsigned int module_id, ifx_rcu_callbackfn callbackfn, unsigned long arg) { unsigned long sys_flags; ifx_rcu_handler_t *p_handler; ifx_rcu_handler_t *p_cur; if ( reset_domain_id >= NUM_ENTITY(g_rcu_domains) || module_id >= IFX_RCU_MODULE_MAX || callbackfn == NULL ) return IFX_ERROR; p_handler = (ifx_rcu_handler_t *)kmalloc(sizeof(*p_handler), GFP_KERNEL); if ( p_handler == NULL ) return IFX_ERROR; p_handler->fn = callbackfn; p_handler->arg = arg; p_handler->module_id = module_id; spin_lock_irqsave(&g_rcu_lock, sys_flags); for ( p_cur = g_rcu_domains[reset_domain_id].handlers; p_cur != NULL; p_cur = p_cur->next ) if ( p_cur->module_id == module_id ) break; if ( p_cur != NULL ) { p_cur->fn = callbackfn; p_cur->arg = arg; } else { p_handler->next = g_rcu_domains[reset_domain_id].handlers; g_rcu_domains[reset_domain_id].handlers = p_handler; } spin_unlock_irqrestore(&g_rcu_lock, sys_flags); if ( p_cur != NULL ) kfree(p_handler); return IFX_SUCCESS; } EXPORT_SYMBOL(ifx_rcu_request); /*! \fn int ifx_rcu_free(unsigned int reset_domain_id, unsigned int module_id) \brief Release ownership of one hardware module. User uses this function to release ownership of one hardware module. Driver will not notify this component for reset event if this function return successfully. \param reset_domain_id - unsigned int, hardware module ID \param module_id - unsigned int, driver/component module ID \return IFX_SUCCESS Release successfully. \return IFX_ERROR Release fail. \ingroup IFX_RCU_API */ int ifx_rcu_free(unsigned int reset_domain_id, unsigned int module_id) { unsigned long sys_flags; ifx_rcu_handler_t *p_cur, *p_prev; if ( reset_domain_id >= NUM_ENTITY(g_rcu_domains) || module_id >= IFX_RCU_MODULE_MAX ) return IFX_ERROR; spin_lock_irqsave(&g_rcu_lock, sys_flags); for ( p_prev = NULL, p_cur = g_rcu_domains[reset_domain_id].handlers; p_cur != NULL; p_prev = p_cur, p_cur = p_cur->next ) if ( p_cur->module_id == module_id ) { if ( p_prev != NULL ) p_prev->next = p_cur->next; else g_rcu_domains[reset_domain_id].handlers = p_cur->next; break; } spin_unlock_irqrestore(&g_rcu_lock, sys_flags); if ( p_cur != NULL ) { kfree(p_cur); return IFX_SUCCESS; } else return IFX_ERROR; } EXPORT_SYMBOL(ifx_rcu_free); /*! \fn int ifx_rcu_stat_get(unsigned int reset_domain_id) \brief Get reset status of given hardware module. User uses this function to get reset status of given hardware module. It's a wrapping of function "ifx_rcu_rst_stat_read". \param reset_domain_id - unsigned int, hardware module ID \return 1 in reset status \return 0 normal status \ingroup IFX_RCU_API */ int ifx_rcu_stat_get(unsigned int reset_domain_id) { if ( reset_domain_id >= NUM_ENTITY(g_rcu_domains) ) return 0; return (ifx_rcu_rst_stat_read() & g_rcu_domains[reset_domain_id].rst_stat_mask) ? 1 : 0; } EXPORT_SYMBOL(ifx_rcu_stat_get); /*! \fn int ifx_rcu_rst(unsigned int reset_domain_id, unsigned int module_id) \brief Trigger reset of one hardware module. User uses this function to trigger reset of one hardware module. Driver will give notification to all drivers/components registering for reset of this hardware module. \param reset_domain_id - unsigned int, hardware module ID \param module_id - unsigned int, driver/component module ID \return IFX_SUCCESS Reset successfully. \return IFX_ERROR Reset fail. \ingroup IFX_RCU_API */ int ifx_rcu_rst(unsigned int reset_domain_id, unsigned int module_id) { unsigned long sys_flags; unsigned int domain_id_bits; int domain_id; ifx_rcu_handler_t *p_cur; spin_lock_irqsave(&g_rcu_lock, sys_flags); // trigger pre-reset event, each handler must be as fast as possible, because interrupt is disabled domain_id_bits = g_rcu_domains[reset_domain_id].affected_domains; while ( domain_id_bits != 0 ) { domain_id = clz(domain_id_bits); domain_id_bits ^= 1 << domain_id; for ( p_cur = g_rcu_domains[domain_id].handlers; p_cur != NULL; p_cur = p_cur->next ) if ( p_cur->module_id != module_id ) p_cur->fn(domain_id, module_id, 0, p_cur->arg); } // issue reset ifx_rcu_rst_req_write(g_rcu_domains[reset_domain_id].rst_req_value, g_rcu_domains[reset_domain_id].rst_req_mask); if ( g_rcu_domains[reset_domain_id].latch ) { udelay(g_rcu_domains[reset_domain_id].udelay); ifx_rcu_rst_req_write(~g_rcu_domains[reset_domain_id].rst_req_value, g_rcu_domains[reset_domain_id].rst_req_mask); } else { int max_count = 1000; while ( (ifx_rcu_rst_stat_read() & g_rcu_domains[reset_domain_id].rst_stat_mask) && max_count-- ); if ( max_count < 0 ) { err("timeout during reset domain - %s", g_rcu_domain_name[reset_domain_id]); } } // trigger post-reset event, each handler must be as fast as possible, because interrupt is disabled domain_id_bits = g_rcu_domains[reset_domain_id].affected_domains; while ( domain_id_bits != 0 ) { domain_id = clz(domain_id_bits); domain_id_bits ^= 1 << domain_id; for ( p_cur = g_rcu_domains[domain_id].handlers; p_cur != NULL; p_cur = p_cur->next ) if ( p_cur->module_id != module_id ) p_cur->fn(domain_id, module_id, 1, p_cur->arg); } spin_unlock_irqrestore(&g_rcu_lock, sys_flags); return IFX_SUCCESS; } EXPORT_SYMBOL(ifx_rcu_rst); /* * #################################### * Init/Cleanup API * #################################### */ static int __init ifx_rcu_pre_init(void) { int i; spin_lock_init(&g_rcu_lock); spin_lock_init(&g_rcu_register_lock); for ( i = 0; i < NUM_ENTITY(g_rcu_domains); i++ ) g_rcu_domains[i].handlers = NULL; return IFX_SUCCESS; } /** * ifx_port_init - Initialize port structures * * This function initializes the internal data structures of the driver * and will create the proc file entry and device. * * Return Value: * @OK = OK */ static int __init ifx_rcu_init(void) { int ret; char ver_str[64]; /* register port device */ ret = register_chrdev(IFX_RCU_MAJOR, "ifx_rcu", &g_rcu_fops); if ( ret != 0 ) { err("Can not register RCU device - %d", ret); return ret; } proc_file_create(); ifx_rcu_version(ver_str); printk(KERN_INFO "%s", ver_str); return IFX_SUCCESS; } static void __exit ifx_rcu_exit(void) { ifx_rcu_handler_t *p_cur, *p_free; int i; proc_file_delete(); unregister_chrdev(IFX_RCU_MAJOR, "ifx_rcu"); for ( i = 0; i < NUM_ENTITY(g_rcu_domains); i++ ) { for ( p_free = p_cur = g_rcu_domains[i].handlers; p_cur != NULL; p_free = p_cur) { p_cur = p_cur->next; kfree(p_free); } } } postcore_initcall(ifx_rcu_pre_init); // to be called earlier than other drivers as well as kernel modules module_init(ifx_rcu_init); module_exit(ifx_rcu_exit);