// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
* Freescale DPAA2 Platforms Console Driver
*
* Copyright 2015-2016 Freescale Semiconductor Inc.
* Copyright 2018 NXP
*/
#define pr_fmt(fmt) "dpaa2-console: " fmt
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/miscdevice.h>
#include <linux/platform_device.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/io.h>
/* MC firmware base low/high registers indexes */
#define MCFBALR_OFFSET 0
#define MCFBAHR_OFFSET 1
/* Bit masks used to get the most/least significant part of the MC base addr */
#define MC_FW_ADDR_MASK_HIGH 0x1FFFF
#define MC_FW_ADDR_MASK_LOW 0xE0000000
#define MC_BUFFER_OFFSET 0x01000000
#define MC_BUFFER_SIZE (1024 * 1024 * 16)
#define MC_OFFSET_DELTA MC_BUFFER_OFFSET
#define AIOP_BUFFER_OFFSET 0x06000000
#define AIOP_BUFFER_SIZE (1024 * 1024 * 16)
#define AIOP_OFFSET_DELTA 0
#define LOG_HEADER_FLAG_BUFFER_WRAPAROUND 0x80000000
#define LAST_BYTE(a) ((a) & ~(LOG_HEADER_FLAG_BUFFER_WRAPAROUND))
/* MC and AIOP Magic words */
#define MAGIC_MC 0x4d430100
#define MAGIC_AIOP 0x41494F50
struct log_header {
__le32 magic_word;
char reserved[4];
__le32 buf_start;
__le32 buf_length;
__le32 last_byte;
};
struct console_data {
void __iomem *map_addr;
struct log_header __iomem *hdr;
void __iomem *start_addr;
void __iomem *end_addr;
void __iomem *end_of_data;
void __iomem *cur_ptr;
};
static struct resource mc_base_addr;
static inline void adjust_end(struct console_data *cd)
{
u32 last_byte = readl(&cd->hdr->last_byte);
cd->end_of_data = cd->start_addr + LAST_BYTE(last_byte);
}
static u64 get_mc_fw_base_address(void)
{
u64 mcfwbase = 0ULL;
u32 __iomem *mcfbaregs;
mcfbaregs = ioremap(mc_base_addr.start, resource_size(&mc_base_addr));
if (!mcfbaregs) {
pr_err("could not map MC Firmware Base registers\n");
return 0;
}
mcfwbase = readl(mcfbaregs + MCFBAHR_OFFSET) &
MC_FW_ADDR_MASK_HIGH;
mcfwbase <<= 32;
mcfwbase |= readl(mcfbaregs + MCFBALR_OFFSET) & MC_FW_ADDR_MASK_LOW;
iounmap(mcfbaregs);
pr_debug("MC base address at 0x%016llx\n", mcfwbase);
return mcfwbase;
}
static ssize_t dpaa2_console_size(struct console_data *cd)
{
ssize_t size;
if (cd->cur_ptr <= cd->end_of_data)
size = cd->end_of_data - cd->cur_ptr;
else
size = (cd->end_addr - cd->cur_ptr) +
(cd->end_of_data - cd->start_addr);
return size;
}
static int dpaa2_generic_console_open(struct inode *node, struct file *fp,
u64 offset, u64 size,
u32 expected_magic,
u32 offset_delta)
{
u32 read_magic, wrapped, last_byte, buf_start, buf_length;
struct console_data *cd;
u64 base_addr;
int err;
cd = kmalloc(sizeof(*cd), GFP_KERNEL);
if (!cd)
return -ENOMEM;
base_addr = get_mc_fw_base_address();
if (!base_addr) {
err = -EIO;
goto err_fwba;
}
cd->map_addr = ioremap(base_addr + offset, size);
if (!cd->map_addr) {
pr_err("cannot map console log memory\n");
err = -EIO;
goto err_ioremap;
}
cd->hdr = (struct log_header __iomem *)cd->map_addr;
read_magic = readl(&cd->hdr->magic_word);
last_byte = readl(&cd->hdr->last_byte);
buf_start = readl(&cd->hdr->buf_start);
buf_length = readl(&cd->hdr->buf_length);
if (read_magic != expected_magic) {
pr_warn("expected = %08x, read = %08x\n",
expected_magic, read_magic);
err = -EIO;
goto err_magic;
}
cd->start_addr = cd->map_addr + buf_start - offset_delta;
cd->end_addr = cd->start_addr + buf_length;
wrapped = last_byte & LOG_HEADER_FLAG_BUFFER_WRAPAROUND;
adjust_end(cd);
if (wrapped && cd->end_of_data != cd->end_addr)
cd->cur_ptr = cd->end_of_data + 1;
else
cd->cur_ptr = cd->start_addr;
fp->private_data = cd;
return 0;
err_magic:
iounmap(cd->map_addr);
err_ioremap:
err_fwba:
kfree(cd);
return err;
}
static int dpaa2_mc_console_open(struct inode *node, struct file *fp)
{
return dpaa2_generic_console_open(node, fp,
MC_BUFFER_OFFSET, MC_BUFFER_SIZE,
MAGIC_MC, MC_OFFSET_DELTA);
}
static int dpaa2_aiop_console_open(struct inode *node, struct file *fp)
{
return dpaa2_generic_console_open(node, fp,
AIOP_BUFFER_OFFSET, AIOP_BUFFER_SIZE,
MAGIC_AIOP, AIOP_OFFSET_DELTA);
}
static int dpaa2_console_close(struct inode *node, struct file *fp)
{
struct console_data *cd = fp->private_data;
iounmap(cd->map_addr);
kfree(cd);
return 0;
}
static ssize_t dpaa2_console_read(struct file *fp, char __user *buf,
size_t count, loff_t *f_pos)
{
struct console_data *cd = fp->private_data;
size_t bytes = dpaa2_console_size(cd);
size_t bytes_end = cd->end_addr - cd->cur_ptr;
size_t written = 0;
void *kbuf;
int err;
/* Check if we need to adjust the end of data addr */
adjust_end(cd);
if (cd->end_of_data == cd->cur_ptr)
return 0;
if (count < bytes)
bytes = count;
kbuf = kmalloc(bytes, GFP_KERNEL);
if (!kbuf)
return -ENOMEM;
if (bytes > bytes_end) {
memcpy_fromio(kbuf, cd->cur_ptr, bytes_end);
if (copy_to_user(buf, kbuf, bytes_end)) {
err = -EFAULT;
goto err_free_buf;
}
buf += bytes_end;
cd->cur_ptr = cd->start_addr;
bytes -= bytes_end;
written += bytes_end;
}
memcpy_fromio(kbuf, cd->cur_ptr, bytes);
if (copy_to_user(buf, kbuf, bytes)) {
err = -EFAULT;
goto err_free_buf;
}
cd->cur_ptr += bytes;
written += bytes;
kfree(kbuf);
return written;
err_free_buf:
kfree(kbuf);
return err;
}
static const struct file_operations dpaa2_mc_console_fops = {
.owner = THIS_MODULE,
.open = dpaa2_mc_console_open,
.release = dpaa2_console_close,
.read = dpaa2_console_read,
};
static struct miscdevice dpaa2_mc_console_dev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "dpaa2_mc_console",
.fops = &dpaa2_mc_console_fops
};
static const struct file_operations dpaa2_aiop_console_fops = {
.owner = THIS_MODULE,
.open = dpaa2_aiop_console_open,
.release = dpaa2_console_close,
.read = dpaa2_console_read,
};
static struct miscdevice dpaa2_aiop_console_dev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "dpaa2_aiop_console",
.fops = &dpaa2_aiop_console_fops
};
static int dpaa2_console_probe(struct platform_device *pdev)
{
int error;
error = of_address_to_resource(pdev->dev.of_node, 0, &mc_base_addr);
if (error < 0) {
pr_err("of_address_to_resource() failed for %pOF with %d\n",
pdev->dev.of_node, error);
return error;
}
error = misc_register(&dpaa2_mc_console_dev);
if (error) {
pr_err("cannot register device %s\n",
dpaa2_mc_console_dev.name);
goto err_register_mc;
}
error = misc_register(&dpaa2_aiop_console_dev);
if (error) {
pr_err("cannot register device %s\n",
dpaa2_aiop_console_dev.name);
goto err_register_aiop;
}
return 0;
err_register_aiop:
misc_deregister(&dpaa2_mc_console_dev);
err_register_mc:
return error;
}
static void dpaa2_console_remove(struct platform_device *pdev)
{
misc_deregister(&dpaa2_mc_console_dev);
misc_deregister(&dpaa2_aiop_console_dev);
}
static const struct of_device_id dpaa2_console_match_table[] = {
{ .compatible = "fsl,dpaa2-console",},
{},
};
MODULE_DEVICE_TABLE(of, dpaa2_console_match_table);
static struct platform_driver dpaa2_console_driver = {
.driver = {
.name = "dpaa2-console",
.pm = NULL,
.of_match_table = dpaa2_console_match_table,
},
.probe = dpaa2_console_probe,
.remove_new = dpaa2_console_remove,
};
module_platform_driver(dpaa2_console_driver);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Roy Pledge <[email protected]>");
MODULE_DESCRIPTION("DPAA2 console driver");
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