From e1262efb9bf9864532c0dfca2b2e222aee7bd0a5 Mon Sep 17 00:00:00 2001 From: Arkady Miasnikov Date: Mon, 18 Jun 2012 16:21:12 +0300 Subject: [PATCH] wlcore: access the firmware memory via debugfs Applications running in the user space needs access to the memory of the chip. Examples of such access - read/write global variables - access to firmware log - dump memory after firmware panic event Arbitrary 4-bytes aligned location can be accessed by read/write file wlcore/mem [Check return value of wlcore_raw_read/write and wlcore_set_partition calls as required by the recent IO changes. -- Luca] Signed-off-by: Arkady Miasnikov Signed-off-by: Luciano Coelho --- drivers/net/wireless/ti/wlcore/debugfs.c | 192 +++++++++++++++++++++++ 1 file changed, 192 insertions(+) diff --git a/drivers/net/wireless/ti/wlcore/debugfs.c b/drivers/net/wireless/ti/wlcore/debugfs.c index 1768f37049b..80dbc5304fa 100644 --- a/drivers/net/wireless/ti/wlcore/debugfs.c +++ b/drivers/net/wireless/ti/wlcore/debugfs.c @@ -38,6 +38,8 @@ /* ms */ #define WL1271_DEBUGFS_STATS_LIFETIME 1000 +#define WLCORE_MAX_BLOCK_SIZE ((size_t)(4*PAGE_SIZE)) + /* debugfs macros idea from mac80211 */ int wl1271_format_buffer(char __user *userbuf, size_t count, loff_t *ppos, char *fmt, ...) @@ -1025,6 +1027,195 @@ static const struct file_operations sleep_auth_ops = { .llseek = default_llseek, }; +static ssize_t dev_mem_read(struct file *file, + char __user *user_buf, size_t count, + loff_t *ppos) +{ + struct wl1271 *wl = file->private_data; + struct wlcore_partition_set part, old_part; + size_t bytes = count; + int ret; + char *buf; + + /* only requests of dword-aligned size and offset are supported */ + if (bytes % 4) + return -EINVAL; + + if (*ppos % 4) + return -EINVAL; + + /* function should return in reasonable time */ + bytes = min(bytes, WLCORE_MAX_BLOCK_SIZE); + + if (bytes == 0) + return -EINVAL; + + memset(&part, 0, sizeof(part)); + part.mem.start = file->f_pos; + part.mem.size = bytes; + + buf = kmalloc(bytes, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + mutex_lock(&wl->mutex); + + if (wl->state == WL1271_STATE_OFF) { + ret = -EFAULT; + goto skip_read; + } + + ret = wl1271_ps_elp_wakeup(wl); + if (ret < 0) + goto skip_read; + + /* store current partition and switch partition */ + memcpy(&old_part, &wl->curr_part, sizeof(old_part)); + ret = wlcore_set_partition(wl, &part); + if (ret < 0) + goto part_err; + + ret = wlcore_raw_read(wl, 0, buf, bytes, false); + if (ret < 0) + goto read_err; + +read_err: + /* recover partition */ + ret = wlcore_set_partition(wl, &old_part); + if (ret < 0) + goto part_err; + +part_err: + wl1271_ps_elp_sleep(wl); + +skip_read: + mutex_unlock(&wl->mutex); + + if (ret == 0) { + ret = copy_to_user(user_buf, buf, bytes); + if (ret < bytes) { + bytes -= ret; + *ppos += bytes; + ret = 0; + } else { + ret = -EFAULT; + } + } + + kfree(buf); + + return ((ret == 0) ? bytes : ret); +} + +static ssize_t dev_mem_write(struct file *file, const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct wl1271 *wl = file->private_data; + struct wlcore_partition_set part, old_part; + size_t bytes = count; + int ret; + char *buf; + + /* only requests of dword-aligned size and offset are supported */ + if (bytes % 4) + return -EINVAL; + + if (*ppos % 4) + return -EINVAL; + + /* function should return in reasonable time */ + bytes = min(bytes, WLCORE_MAX_BLOCK_SIZE); + + if (bytes == 0) + return -EINVAL; + + memset(&part, 0, sizeof(part)); + part.mem.start = file->f_pos; + part.mem.size = bytes; + + buf = kmalloc(bytes, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = copy_from_user(buf, user_buf, bytes); + if (ret) { + ret = -EFAULT; + goto err_out; + } + + mutex_lock(&wl->mutex); + + if (wl->state == WL1271_STATE_OFF) { + ret = -EFAULT; + goto skip_write; + } + + ret = wl1271_ps_elp_wakeup(wl); + if (ret < 0) + goto skip_write; + + /* store current partition and switch partition */ + memcpy(&old_part, &wl->curr_part, sizeof(old_part)); + ret = wlcore_set_partition(wl, &part); + if (ret < 0) + goto part_err; + + ret = wlcore_raw_write(wl, 0, buf, bytes, false); + if (ret < 0) + goto write_err; + +write_err: + /* recover partition */ + ret = wlcore_set_partition(wl, &old_part); + if (ret < 0) + goto part_err; + +part_err: + wl1271_ps_elp_sleep(wl); + +skip_write: + mutex_unlock(&wl->mutex); + + if (ret == 0) + *ppos += bytes; + +err_out: + kfree(buf); + + return ((ret == 0) ? bytes : ret); +} + +static loff_t dev_mem_seek(struct file *file, loff_t offset, int orig) +{ + loff_t ret; + + /* only requests of dword-aligned size and offset are supported */ + if (offset % 4) + return -EINVAL; + + switch (orig) { + case SEEK_SET: + file->f_pos = offset; + ret = file->f_pos; + break; + case SEEK_CUR: + file->f_pos += offset; + ret = file->f_pos; + break; + default: + ret = -EINVAL; + } + + return ret; +} + +static const struct file_operations dev_mem_ops = { + .open = simple_open, + .read = dev_mem_read, + .write = dev_mem_write, + .llseek = dev_mem_seek, +}; + static int wl1271_debugfs_add_files(struct wl1271 *wl, struct dentry *rootdir) { @@ -1059,6 +1250,7 @@ static int wl1271_debugfs_add_files(struct wl1271 *wl, DEBUGFS_ADD_PREFIX(rx_streaming, interval, streaming); DEBUGFS_ADD_PREFIX(rx_streaming, always, streaming); + DEBUGFS_ADD_PREFIX(dev, mem, rootdir); return 0; -- 2.20.1