linux/drivers/firmware/tegra/bpmp-debugfs.c

445 lines
9.7 KiB
C

/*
* Copyright (c) 2017, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
*/
#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;
}
static int mrq_is_supported(struct tegra_bpmp *bpmp, unsigned int mrq)
{
struct mrq_query_abi_request req = { .mrq = cpu_to_le32(mrq) };
struct mrq_query_abi_response resp;
struct tegra_bpmp_message msg = {
.mrq = MRQ_QUERY_ABI,
.tx = {
.data = &req,
.size = sizeof(req),
},
.rx = {
.data = &resp,
.size = sizeof(resp),
},
};
int ret;
ret = tegra_bpmp_transfer(bpmp, &msg);
if (ret < 0) {
/* something went wrong; assume not supported */
dev_warn(bpmp->dev, "tegra_bpmp_transfer failed (%d)\n", ret);
return 0;
}
return resp.status ? 0 : 1;
}
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 (!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;
}