diff options
Diffstat (limited to 'drivers/sbus/char/jsflash.c')
-rw-r--r-- | drivers/sbus/char/jsflash.c | 627 |
1 files changed, 627 insertions, 0 deletions
diff --git a/drivers/sbus/char/jsflash.c b/drivers/sbus/char/jsflash.c new file mode 100644 index 0000000..c12c504 --- /dev/null +++ b/drivers/sbus/char/jsflash.c @@ -0,0 +1,627 @@ +/* + * drivers/sbus/char/jsflash.c + * + * Copyright (C) 1991, 1992 Linus Torvalds (drivers/char/mem.c) + * Copyright (C) 1997 Eddie C. Dost (drivers/sbus/char/flash.c) + * Copyright (C) 1997-2000 Pavel Machek <pavel@ucw.cz> (drivers/block/nbd.c) + * Copyright (C) 1999-2000 Pete Zaitcev + * + * This driver is used to program OS into a Flash SIMM on + * Krups and Espresso platforms. + * + * TODO: do not allow erase/programming if file systems are mounted. + * TODO: Erase/program both banks of a 8MB SIMM. + * + * It is anticipated that programming an OS Flash will be a routine + * procedure. In the same time it is exeedingly dangerous because + * a user can program its OBP flash with OS image and effectively + * kill the machine. + * + * This driver uses an interface different from Eddie's flash.c + * as a silly safeguard. + * + * XXX The flash.c manipulates page caching characteristics in a certain + * dubious way; also it assumes that remap_pfn_range() can remap + * PCI bus locations, which may be false. ioremap() must be used + * instead. We should discuss this. + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/miscdevice.h> +#include <linux/slab.h> +#include <linux/fcntl.h> +#include <linux/poll.h> +#include <linux/init.h> +#include <linux/string.h> +#include <linux/smp_lock.h> +#include <linux/genhd.h> +#include <linux/blkdev.h> + +#define MAJOR_NR JSFD_MAJOR + +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/io.h> +#include <asm/pcic.h> +#include <asm/oplib.h> + +#include <asm/jsflash.h> /* ioctl arguments. <linux/> ?? */ +#define JSFIDSZ (sizeof(struct jsflash_ident_arg)) +#define JSFPRGSZ (sizeof(struct jsflash_program_arg)) + +/* + * Our device numbers have no business in system headers. + * The only thing a user knows is the device name /dev/jsflash. + * + * Block devices are laid out like this: + * minor+0 - Bootstrap, for 8MB SIMM 0x20400000[0x800000] + * minor+1 - Filesystem to mount, normally 0x20400400[0x7ffc00] + * minor+2 - Whole flash area for any case... 0x20000000[0x01000000] + * Total 3 minors per flash device. + * + * It is easier to have static size vectors, so we define + * a total minor range JSF_MAX, which must cover all minors. + */ +/* character device */ +#define JSF_MINOR 178 /* 178 is registered with hpa */ +/* block device */ +#define JSF_MAX 3 /* 3 minors wasted total so far. */ +#define JSF_NPART 3 /* 3 minors per flash device */ +#define JSF_PART_BITS 2 /* 2 bits of minors to cover JSF_NPART */ +#define JSF_PART_MASK 0x3 /* 2 bits mask */ + +/* + * Access functions. + * We could ioremap(), but it's easier this way. + */ +static unsigned int jsf_inl(unsigned long addr) +{ + unsigned long retval; + + __asm__ __volatile__("lda [%1] %2, %0\n\t" : + "=r" (retval) : + "r" (addr), "i" (ASI_M_BYPASS)); + return retval; +} + +static void jsf_outl(unsigned long addr, __u32 data) +{ + + __asm__ __volatile__("sta %0, [%1] %2\n\t" : : + "r" (data), "r" (addr), "i" (ASI_M_BYPASS) : + "memory"); +} + +/* + * soft carrier + */ + +struct jsfd_part { + unsigned long dbase; + unsigned long dsize; +}; + +struct jsflash { + unsigned long base; + unsigned long size; + unsigned long busy; /* In use? */ + struct jsflash_ident_arg id; + /* int mbase; */ /* Minor base, typically zero */ + struct jsfd_part dv[JSF_NPART]; +}; + +/* + * We do not map normal memory or obio as a safety precaution. + * But offsets are real, for ease of userland programming. + */ +#define JSF_BASE_TOP 0x30000000 +#define JSF_BASE_ALL 0x20000000 + +#define JSF_BASE_JK 0x20400000 + +/* + */ +static struct gendisk *jsfd_disk[JSF_MAX]; + +/* + * Let's pretend we may have several of these... + */ +static struct jsflash jsf0; + +/* + * Wait for AMD to finish its embedded algorithm. + * We use the Toggle bit DQ6 (0x40) because it does not + * depend on the data value as /DATA bit DQ7 does. + * + * XXX Do we need any timeout here? So far it never hanged, beware broken hw. + */ +static void jsf_wait(unsigned long p) { + unsigned int x1, x2; + + for (;;) { + x1 = jsf_inl(p); + x2 = jsf_inl(p); + if ((x1 & 0x40404040) == (x2 & 0x40404040)) return; + } +} + +/* + * Programming will only work if Flash is clean, + * we leave it to the programmer application. + * + * AMD must be programmed one byte at a time; + * thus, Simple Tech SIMM must be written 4 bytes at a time. + * + * Write waits for the chip to become ready after the write + * was finished. This is done so that application would read + * consistent data after the write is done. + */ +static void jsf_write4(unsigned long fa, u32 data) { + + jsf_outl(fa, 0xAAAAAAAA); /* Unlock 1 Write 1 */ + jsf_outl(fa, 0x55555555); /* Unlock 1 Write 2 */ + jsf_outl(fa, 0xA0A0A0A0); /* Byte Program */ + jsf_outl(fa, data); + + jsf_wait(fa); +} + +/* + */ +static void jsfd_read(char *buf, unsigned long p, size_t togo) { + union byte4 { + char s[4]; + unsigned int n; + } b; + + while (togo >= 4) { + togo -= 4; + b.n = jsf_inl(p); + memcpy(buf, b.s, 4); + p += 4; + buf += 4; + } +} + +static void jsfd_do_request(request_queue_t *q) +{ + struct request *req; + + while ((req = elv_next_request(q)) != NULL) { + struct jsfd_part *jdp = req->rq_disk->private_data; + unsigned long offset = req->sector << 9; + size_t len = req->current_nr_sectors << 9; + + if ((offset + len) > jdp->dsize) { + end_request(req, 0); + continue; + } + + if (rq_data_dir(req) != READ) { + printk(KERN_ERR "jsfd: write\n"); + end_request(req, 0); + continue; + } + + if ((jdp->dbase & 0xff000000) != 0x20000000) { + printk(KERN_ERR "jsfd: bad base %x\n", (int)jdp->dbase); + end_request(req, 0); + continue; + } + + jsfd_read(req->buffer, jdp->dbase + offset, len); + + end_request(req, 1); + } +} + +/* + * The memory devices use the full 32/64 bits of the offset, and so we cannot + * check against negative addresses: they are ok. The return value is weird, + * though, in that case (0). + * + * also note that seeking relative to the "end of file" isn't supported: + * it has no meaning, so it returns -EINVAL. + */ +static loff_t jsf_lseek(struct file * file, loff_t offset, int orig) +{ + loff_t ret; + + lock_kernel(); + switch (orig) { + case 0: + file->f_pos = offset; + ret = file->f_pos; + break; + case 1: + file->f_pos += offset; + ret = file->f_pos; + break; + default: + ret = -EINVAL; + } + unlock_kernel(); + return ret; +} + +/* + * OS SIMM Cannot be read in other size but a 32bits word. + */ +static ssize_t jsf_read(struct file * file, char * buf, + size_t togo, loff_t *ppos) +{ + unsigned long p = *ppos; + char *tmp = buf; + + union byte4 { + char s[4]; + unsigned int n; + } b; + + if (p < JSF_BASE_ALL || p >= JSF_BASE_TOP) { + return 0; + } + + if ((p + togo) < p /* wrap */ + || (p + togo) >= JSF_BASE_TOP) { + togo = JSF_BASE_TOP - p; + } + + if (p < JSF_BASE_ALL && togo != 0) { +#if 0 /* __bzero XXX */ + size_t x = JSF_BASE_ALL - p; + if (x > togo) x = togo; + clear_user(tmp, x); + tmp += x; + p += x; + togo -= x; +#else + /* + * Implementation of clear_user() calls __bzero + * without regard to modversions, + * so we cannot build a module. + */ + return 0; +#endif + } + + while (togo >= 4) { + togo -= 4; + b.n = jsf_inl(p); + if (copy_to_user(tmp, b.s, 4)) + return -EFAULT; + tmp += 4; + p += 4; + } + + /* + * XXX Small togo may remain if 1 byte is ordered. + * It would be nice if we did a word size read and unpacked it. + */ + + *ppos = p; + return tmp-buf; +} + +static ssize_t jsf_write(struct file * file, const char * buf, + size_t count, loff_t *ppos) +{ + return -ENOSPC; +} + +/* + */ +static int jsf_ioctl_erase(unsigned long arg) +{ + unsigned long p; + + /* p = jsf0.base; hits wrong bank */ + p = 0x20400000; + + jsf_outl(p, 0xAAAAAAAA); /* Unlock 1 Write 1 */ + jsf_outl(p, 0x55555555); /* Unlock 1 Write 2 */ + jsf_outl(p, 0x80808080); /* Erase setup */ + jsf_outl(p, 0xAAAAAAAA); /* Unlock 2 Write 1 */ + jsf_outl(p, 0x55555555); /* Unlock 2 Write 2 */ + jsf_outl(p, 0x10101010); /* Chip erase */ + +#if 0 + /* + * This code is ok, except that counter based timeout + * has no place in this world. Let's just drop timeouts... + */ + { + int i; + __u32 x; + for (i = 0; i < 1000000; i++) { + x = jsf_inl(p); + if ((x & 0x80808080) == 0x80808080) break; + } + if ((x & 0x80808080) != 0x80808080) { + printk("jsf0: erase timeout with 0x%08x\n", x); + } else { + printk("jsf0: erase done with 0x%08x\n", x); + } + } +#else + jsf_wait(p); +#endif + + return 0; +} + +/* + * Program a block of flash. + * Very simple because we can do it byte by byte anyway. + */ +static int jsf_ioctl_program(unsigned long arg) +{ + struct jsflash_program_arg abuf; + char *uptr; + unsigned long p; + unsigned int togo; + union { + unsigned int n; + char s[4]; + } b; + + if (copy_from_user(&abuf, (char *)arg, JSFPRGSZ)) + return -EFAULT; + p = abuf.off; + togo = abuf.size; + if ((togo & 3) || (p & 3)) return -EINVAL; + + uptr = (char *) (unsigned long) abuf.data; + while (togo != 0) { + togo -= 4; + if (copy_from_user(&b.s[0], uptr, 4)) + return -EFAULT; + jsf_write4(p, b.n); + p += 4; + uptr += 4; + } + + return 0; +} + +static int jsf_ioctl(struct inode *inode, struct file *f, unsigned int cmd, + unsigned long arg) +{ + int error = -ENOTTY; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + switch (cmd) { + case JSFLASH_IDENT: + if (copy_to_user((void *)arg, &jsf0.id, JSFIDSZ)) + return -EFAULT; + break; + case JSFLASH_ERASE: + error = jsf_ioctl_erase(arg); + break; + case JSFLASH_PROGRAM: + error = jsf_ioctl_program(arg); + break; + } + + return error; +} + +static int jsf_mmap(struct file * file, struct vm_area_struct * vma) +{ + return -ENXIO; +} + +static int jsf_open(struct inode * inode, struct file * filp) +{ + + if (jsf0.base == 0) return -ENXIO; + if (test_and_set_bit(0, (void *)&jsf0.busy) != 0) + return -EBUSY; + + return 0; /* XXX What security? */ +} + +static int jsf_release(struct inode *inode, struct file *file) +{ + jsf0.busy = 0; + return 0; +} + +static struct file_operations jsf_fops = { + .owner = THIS_MODULE, + .llseek = jsf_lseek, + .read = jsf_read, + .write = jsf_write, + .ioctl = jsf_ioctl, + .mmap = jsf_mmap, + .open = jsf_open, + .release = jsf_release, +}; + +static struct miscdevice jsf_dev = { JSF_MINOR, "jsflash", &jsf_fops }; + +static struct block_device_operations jsfd_fops = { + .owner = THIS_MODULE, +}; + +static int jsflash_init(void) +{ + int rc; + struct jsflash *jsf; + int node; + char banner[128]; + struct linux_prom_registers reg0; + + node = prom_getchild(prom_root_node); + node = prom_searchsiblings(node, "flash-memory"); + if (node != 0 && node != -1) { + if (prom_getproperty(node, "reg", + (char *)®0, sizeof(reg0)) == -1) { + printk("jsflash: no \"reg\" property\n"); + return -ENXIO; + } + if (reg0.which_io != 0) { + printk("jsflash: bus number nonzero: 0x%x:%x\n", + reg0.which_io, reg0.phys_addr); + return -ENXIO; + } + /* + * Flash may be somewhere else, for instance on Ebus. + * So, don't do the following check for IIep flash space. + */ +#if 0 + if ((reg0.phys_addr >> 24) != 0x20) { + printk("jsflash: suspicious address: 0x%x:%x\n", + reg0.which_io, reg0.phys_addr); + return -ENXIO; + } +#endif + if ((int)reg0.reg_size <= 0) { + printk("jsflash: bad size 0x%x\n", (int)reg0.reg_size); + return -ENXIO; + } + } else { + /* XXX Remove this code once PROLL ID12 got widespread */ + printk("jsflash: no /flash-memory node, use PROLL >= 12\n"); + prom_getproperty(prom_root_node, "banner-name", banner, 128); + if (strcmp (banner, "JavaStation-NC") != 0 && + strcmp (banner, "JavaStation-E") != 0) { + return -ENXIO; + } + reg0.which_io = 0; + reg0.phys_addr = 0x20400000; + reg0.reg_size = 0x00800000; + } + + /* Let us be really paranoid for modifications to probing code. */ + /* extern enum sparc_cpu sparc_cpu_model; */ /* in <asm/system.h> */ + if (sparc_cpu_model != sun4m) { + /* We must be on sun4m because we use MMU Bypass ASI. */ + return -ENXIO; + } + + if (jsf0.base == 0) { + jsf = &jsf0; + + jsf->base = reg0.phys_addr; + jsf->size = reg0.reg_size; + + /* XXX Redo the userland interface. */ + jsf->id.off = JSF_BASE_ALL; + jsf->id.size = 0x01000000; /* 16M - all segments */ + strcpy(jsf->id.name, "Krups_all"); + + jsf->dv[0].dbase = jsf->base; + jsf->dv[0].dsize = jsf->size; + jsf->dv[1].dbase = jsf->base + 1024; + jsf->dv[1].dsize = jsf->size - 1024; + jsf->dv[2].dbase = JSF_BASE_ALL; + jsf->dv[2].dsize = 0x01000000; + + printk("Espresso Flash @0x%lx [%d MB]\n", jsf->base, + (int) (jsf->size / (1024*1024))); + } + + if ((rc = misc_register(&jsf_dev)) != 0) { + printk(KERN_ERR "jsf: unable to get misc minor %d\n", + JSF_MINOR); + jsf0.base = 0; + return rc; + } + + return 0; +} + +static struct request_queue *jsf_queue; + +static int jsfd_init(void) +{ + static DEFINE_SPINLOCK(lock); + struct jsflash *jsf; + struct jsfd_part *jdp; + int err; + int i; + + if (jsf0.base == 0) + return -ENXIO; + + err = -ENOMEM; + for (i = 0; i < JSF_MAX; i++) { + struct gendisk *disk = alloc_disk(1); + if (!disk) + goto out; + jsfd_disk[i] = disk; + } + + if (register_blkdev(JSFD_MAJOR, "jsfd")) { + err = -EIO; + goto out; + } + + jsf_queue = blk_init_queue(jsfd_do_request, &lock); + if (!jsf_queue) { + err = -ENOMEM; + unregister_blkdev(JSFD_MAJOR, "jsfd"); + goto out; + } + + for (i = 0; i < JSF_MAX; i++) { + struct gendisk *disk = jsfd_disk[i]; + if ((i & JSF_PART_MASK) >= JSF_NPART) continue; + jsf = &jsf0; /* actually, &jsfv[i >> JSF_PART_BITS] */ + jdp = &jsf->dv[i&JSF_PART_MASK]; + + disk->major = JSFD_MAJOR; + disk->first_minor = i; + sprintf(disk->disk_name, "jsfd%d", i); + disk->fops = &jsfd_fops; + set_capacity(disk, jdp->dsize >> 9); + disk->private_data = jdp; + disk->queue = jsf_queue; + add_disk(disk); + set_disk_ro(disk, 1); + } + return 0; +out: + while (i--) + put_disk(jsfd_disk[i]); + return err; +} + +MODULE_LICENSE("GPL"); + +static int __init jsflash_init_module(void) { + int rc; + + if ((rc = jsflash_init()) == 0) { + jsfd_init(); + return 0; + } + return rc; +} + +static void __exit jsflash_cleanup_module(void) +{ + int i; + + for (i = 0; i < JSF_MAX; i++) { + if ((i & JSF_PART_MASK) >= JSF_NPART) continue; + del_gendisk(jsfd_disk[i]); + put_disk(jsfd_disk[i]); + } + if (jsf0.busy) + printk("jsf0: cleaning busy unit\n"); + jsf0.base = 0; + jsf0.busy = 0; + + misc_deregister(&jsf_dev); + if (unregister_blkdev(JSFD_MAJOR, "jsfd") != 0) + printk("jsfd: cleanup_module failed\n"); + blk_cleanup_queue(jsf_queue); +} + +module_init(jsflash_init_module); +module_exit(jsflash_cleanup_module); |