| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved. |
| */ |
| #include <linux/debugfs.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/uaccess.h> |
| |
| #include <soc/tegra/bpmp.h> |
| #include <soc/tegra/bpmp-abi.h> |
| |
| struct seqbuf { |
| char *buf; |
| size_t pos; |
| size_t size; |
| }; |
| |
| static void seqbuf_init(struct seqbuf *seqbuf, void *buf, size_t size) |
| { |
| seqbuf->buf = buf; |
| seqbuf->size = size; |
| seqbuf->pos = 0; |
| } |
| |
| static size_t seqbuf_avail(struct seqbuf *seqbuf) |
| { |
| return seqbuf->pos < seqbuf->size ? seqbuf->size - seqbuf->pos : 0; |
| } |
| |
| static size_t seqbuf_status(struct seqbuf *seqbuf) |
| { |
| return seqbuf->pos <= seqbuf->size ? 0 : -EOVERFLOW; |
| } |
| |
| static int seqbuf_eof(struct seqbuf *seqbuf) |
| { |
| return seqbuf->pos >= seqbuf->size; |
| } |
| |
| static int seqbuf_read(struct seqbuf *seqbuf, void *buf, size_t nbyte) |
| { |
| nbyte = min(nbyte, seqbuf_avail(seqbuf)); |
| memcpy(buf, seqbuf->buf + seqbuf->pos, nbyte); |
| seqbuf->pos += nbyte; |
| return seqbuf_status(seqbuf); |
| } |
| |
| static int seqbuf_read_u32(struct seqbuf *seqbuf, uint32_t *v) |
| { |
| int err; |
| |
| err = seqbuf_read(seqbuf, v, 4); |
| *v = le32_to_cpu(*v); |
| return err; |
| } |
| |
| static int seqbuf_read_str(struct seqbuf *seqbuf, const char **str) |
| { |
| *str = seqbuf->buf + seqbuf->pos; |
| seqbuf->pos += strnlen(*str, seqbuf_avail(seqbuf)); |
| seqbuf->pos++; |
| return seqbuf_status(seqbuf); |
| } |
| |
| static void seqbuf_seek(struct seqbuf *seqbuf, ssize_t offset) |
| { |
| seqbuf->pos += offset; |
| } |
| |
| /* map filename in Linux debugfs to corresponding entry in BPMP */ |
| static const char *get_filename(struct tegra_bpmp *bpmp, |
| const struct file *file, char *buf, int size) |
| { |
| char root_path_buf[512]; |
| const char *root_path; |
| const char *filename; |
| size_t root_len; |
| |
| root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf, |
| sizeof(root_path_buf)); |
| if (IS_ERR(root_path)) |
| return NULL; |
| |
| root_len = strlen(root_path); |
| |
| filename = dentry_path(file->f_path.dentry, buf, size); |
| if (IS_ERR(filename)) |
| return NULL; |
| |
| if (strlen(filename) < root_len || |
| strncmp(filename, root_path, root_len)) |
| return NULL; |
| |
| filename += root_len; |
| |
| return filename; |
| } |
| |
| static int mrq_debugfs_read(struct tegra_bpmp *bpmp, |
| dma_addr_t name, size_t sz_name, |
| dma_addr_t data, size_t sz_data, |
| size_t *nbytes) |
| { |
| struct mrq_debugfs_request req = { |
| .cmd = cpu_to_le32(CMD_DEBUGFS_READ), |
| .fop = { |
| .fnameaddr = cpu_to_le32((uint32_t)name), |
| .fnamelen = cpu_to_le32((uint32_t)sz_name), |
| .dataaddr = cpu_to_le32((uint32_t)data), |
| .datalen = cpu_to_le32((uint32_t)sz_data), |
| }, |
| }; |
| struct mrq_debugfs_response resp; |
| struct tegra_bpmp_message msg = { |
| .mrq = MRQ_DEBUGFS, |
| .tx = { |
| .data = &req, |
| .size = sizeof(req), |
| }, |
| .rx = { |
| .data = &resp, |
| .size = sizeof(resp), |
| }, |
| }; |
| int err; |
| |
| err = tegra_bpmp_transfer(bpmp, &msg); |
| if (err < 0) |
| return err; |
| |
| *nbytes = (size_t)resp.fop.nbytes; |
| |
| return 0; |
| } |
| |
| static int mrq_debugfs_write(struct tegra_bpmp *bpmp, |
| dma_addr_t name, size_t sz_name, |
| dma_addr_t data, size_t sz_data) |
| { |
| const struct mrq_debugfs_request req = { |
| .cmd = cpu_to_le32(CMD_DEBUGFS_WRITE), |
| .fop = { |
| .fnameaddr = cpu_to_le32((uint32_t)name), |
| .fnamelen = cpu_to_le32((uint32_t)sz_name), |
| .dataaddr = cpu_to_le32((uint32_t)data), |
| .datalen = cpu_to_le32((uint32_t)sz_data), |
| }, |
| }; |
| struct tegra_bpmp_message msg = { |
| .mrq = MRQ_DEBUGFS, |
| .tx = { |
| .data = &req, |
| .size = sizeof(req), |
| }, |
| }; |
| |
| return tegra_bpmp_transfer(bpmp, &msg); |
| } |
| |
| static int mrq_debugfs_dumpdir(struct tegra_bpmp *bpmp, dma_addr_t addr, |
| size_t size, size_t *nbytes) |
| { |
| const struct mrq_debugfs_request req = { |
| .cmd = cpu_to_le32(CMD_DEBUGFS_DUMPDIR), |
| .dumpdir = { |
| .dataaddr = cpu_to_le32((uint32_t)addr), |
| .datalen = cpu_to_le32((uint32_t)size), |
| }, |
| }; |
| struct mrq_debugfs_response resp; |
| struct tegra_bpmp_message msg = { |
| .mrq = MRQ_DEBUGFS, |
| .tx = { |
| .data = &req, |
| .size = sizeof(req), |
| }, |
| .rx = { |
| .data = &resp, |
| .size = sizeof(resp), |
| }, |
| }; |
| int err; |
| |
| err = tegra_bpmp_transfer(bpmp, &msg); |
| if (err < 0) |
| return err; |
| |
| *nbytes = (size_t)resp.dumpdir.nbytes; |
| |
| return 0; |
| } |
| |
| static int debugfs_show(struct seq_file *m, void *p) |
| { |
| struct file *file = m->private; |
| struct inode *inode = file_inode(file); |
| struct tegra_bpmp *bpmp = inode->i_private; |
| const size_t datasize = m->size; |
| const size_t namesize = SZ_256; |
| void *datavirt, *namevirt; |
| dma_addr_t dataphys, namephys; |
| char buf[256]; |
| const char *filename; |
| size_t len, nbytes; |
| int ret; |
| |
| filename = get_filename(bpmp, file, buf, sizeof(buf)); |
| if (!filename) |
| return -ENOENT; |
| |
| namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys, |
| GFP_KERNEL | GFP_DMA32); |
| if (!namevirt) |
| return -ENOMEM; |
| |
| datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys, |
| GFP_KERNEL | GFP_DMA32); |
| if (!datavirt) { |
| ret = -ENOMEM; |
| goto free_namebuf; |
| } |
| |
| len = strlen(filename); |
| strncpy(namevirt, filename, namesize); |
| |
| ret = mrq_debugfs_read(bpmp, namephys, len, dataphys, datasize, |
| &nbytes); |
| |
| if (!ret) |
| seq_write(m, datavirt, nbytes); |
| |
| dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys); |
| free_namebuf: |
| dma_free_coherent(bpmp->dev, namesize, namevirt, namephys); |
| |
| return ret; |
| } |
| |
| static int debugfs_open(struct inode *inode, struct file *file) |
| { |
| return single_open_size(file, debugfs_show, file, SZ_128K); |
| } |
| |
| static ssize_t debugfs_store(struct file *file, const char __user *buf, |
| size_t count, loff_t *f_pos) |
| { |
| struct inode *inode = file_inode(file); |
| struct tegra_bpmp *bpmp = inode->i_private; |
| const size_t datasize = count; |
| const size_t namesize = SZ_256; |
| void *datavirt, *namevirt; |
| dma_addr_t dataphys, namephys; |
| char fnamebuf[256]; |
| const char *filename; |
| size_t len; |
| int ret; |
| |
| filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf)); |
| if (!filename) |
| return -ENOENT; |
| |
| namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys, |
| GFP_KERNEL | GFP_DMA32); |
| if (!namevirt) |
| return -ENOMEM; |
| |
| datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys, |
| GFP_KERNEL | GFP_DMA32); |
| if (!datavirt) { |
| ret = -ENOMEM; |
| goto free_namebuf; |
| } |
| |
| len = strlen(filename); |
| strncpy(namevirt, filename, namesize); |
| |
| if (copy_from_user(datavirt, buf, count)) { |
| ret = -EFAULT; |
| goto free_databuf; |
| } |
| |
| ret = mrq_debugfs_write(bpmp, namephys, len, dataphys, |
| count); |
| |
| free_databuf: |
| dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys); |
| free_namebuf: |
| dma_free_coherent(bpmp->dev, namesize, namevirt, namephys); |
| |
| return ret ?: count; |
| } |
| |
| static const struct file_operations debugfs_fops = { |
| .open = debugfs_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .write = debugfs_store, |
| .release = single_release, |
| }; |
| |
| static int bpmp_populate_dir(struct tegra_bpmp *bpmp, struct seqbuf *seqbuf, |
| struct dentry *parent, uint32_t depth) |
| { |
| int err; |
| uint32_t d, t; |
| const char *name; |
| struct dentry *dentry; |
| |
| while (!seqbuf_eof(seqbuf)) { |
| err = seqbuf_read_u32(seqbuf, &d); |
| if (err < 0) |
| return err; |
| |
| if (d < depth) { |
| seqbuf_seek(seqbuf, -4); |
| /* go up a level */ |
| return 0; |
| } else if (d != depth) { |
| /* malformed data received from BPMP */ |
| return -EIO; |
| } |
| |
| err = seqbuf_read_u32(seqbuf, &t); |
| if (err < 0) |
| return err; |
| err = seqbuf_read_str(seqbuf, &name); |
| if (err < 0) |
| return err; |
| |
| if (t & DEBUGFS_S_ISDIR) { |
| dentry = debugfs_create_dir(name, parent); |
| if (!dentry) |
| return -ENOMEM; |
| err = bpmp_populate_dir(bpmp, seqbuf, dentry, depth+1); |
| if (err < 0) |
| return err; |
| } else { |
| umode_t mode; |
| |
| mode = t & DEBUGFS_S_IRUSR ? S_IRUSR : 0; |
| mode |= t & DEBUGFS_S_IWUSR ? S_IWUSR : 0; |
| dentry = debugfs_create_file(name, mode, |
| parent, bpmp, |
| &debugfs_fops); |
| if (!dentry) |
| return -ENOMEM; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int create_debugfs_mirror(struct tegra_bpmp *bpmp, void *buf, |
| size_t bufsize, struct dentry *root) |
| { |
| struct seqbuf seqbuf; |
| int err; |
| |
| bpmp->debugfs_mirror = debugfs_create_dir("debug", root); |
| if (!bpmp->debugfs_mirror) |
| return -ENOMEM; |
| |
| seqbuf_init(&seqbuf, buf, bufsize); |
| err = bpmp_populate_dir(bpmp, &seqbuf, bpmp->debugfs_mirror, 0); |
| if (err < 0) { |
| debugfs_remove_recursive(bpmp->debugfs_mirror); |
| bpmp->debugfs_mirror = NULL; |
| } |
| |
| return err; |
| } |
| |
| int tegra_bpmp_init_debugfs(struct tegra_bpmp *bpmp) |
| { |
| dma_addr_t phys; |
| void *virt; |
| const size_t sz = SZ_256K; |
| size_t nbytes; |
| int ret; |
| struct dentry *root; |
| |
| if (!tegra_bpmp_mrq_is_supported(bpmp, MRQ_DEBUGFS)) |
| return 0; |
| |
| root = debugfs_create_dir("bpmp", NULL); |
| if (!root) |
| return -ENOMEM; |
| |
| virt = dma_alloc_coherent(bpmp->dev, sz, &phys, |
| GFP_KERNEL | GFP_DMA32); |
| if (!virt) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| ret = mrq_debugfs_dumpdir(bpmp, phys, sz, &nbytes); |
| if (ret < 0) |
| goto free; |
| |
| ret = create_debugfs_mirror(bpmp, virt, nbytes, root); |
| free: |
| dma_free_coherent(bpmp->dev, sz, virt, phys); |
| out: |
| if (ret < 0) |
| debugfs_remove(root); |
| |
| return ret; |
| } |