diff options
Diffstat (limited to 'drivers/soc/marvell/cn10k-rpram.c')
| -rw-r--r-- | drivers/soc/marvell/cn10k-rpram.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/soc/marvell/cn10k-rpram.c b/drivers/soc/marvell/cn10k-rpram.c new file mode 100644 index 000000000000..37f30426862d --- /dev/null +++ b/drivers/soc/marvell/cn10k-rpram.c @@ -0,0 +1,223 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021 Marvell International Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/debugfs.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/arm-smccc.h> +#include <soc/marvell/octeontx/octeontx_smc.h> + +/* Minimum size in MB, 0 means region is disabled + * 16 MB is the minimum size when it is eanbled. + */ +#define MIN_USERDEF_PRESERVE_MEMSZ 0 + +/* Maximum size is 1GB */ +#define MAX_USERDEF_PRESERVE_MEMSZ 1024 + +/* Region size must be multiples of 16 MB */ +#define PRESERVE_MEMSZ_ALIGN 16 + +/* SMC function id to check the platform type is CN10K */ +#define ARM_SMC_SVC_UID 0xc200ff01 +/* SMC function id to update persistent memory */ +#define PLAT_OCTEONTX_PERSIST_DATA_COMMAND 0xc2000b0d +/* Arg 0: UPDATE_USERDEF_PRESERVE_MEMSZ, Update user defined + * preserve memory size + * Arg 1: Size of the preserved memory size + */ +#define UPDATE_USERDEF_PRESERVE_MEMSZ 1 + +static u32 current_rpram_size; +static u32 nextboot_rpram_size; +static u64 current_rpram_base; +static struct dentry *preserve_mem_root; +static const size_t len = PAGE_SIZE; + +static ssize_t cn10k_rpram_info_read(struct file *f, char __user *user_buf, + size_t count, loff_t *off) +{ + ssize_t out, pos = 0; + unsigned long addr = get_zeroed_page(GFP_KERNEL); + char *buf = (char *)addr; + + if (!buf) + return -ENOMEM; + + pos += snprintf(buf+pos, len - pos, "RPRAM size %d MB @0x%llx\n", + current_rpram_size, (unsigned long long) current_rpram_base); + + out = simple_read_from_buffer(user_buf, count, off, + buf, pos); + + free_page(addr); + return out; +} + +static ssize_t cn10k_rpram_info_write(struct file *f, const char __user *user_buf, + size_t count, loff_t *off) +{ + return 0; +} + +static ssize_t cn10k_rpram_config_read(struct file *f, char __user *user_buf, + size_t count, loff_t *off) +{ + ssize_t out, pos = 0; + unsigned long addr = get_zeroed_page(GFP_KERNEL); + char *buf = (char *)addr; + + if (!buf) + return -ENOMEM; + + pos += snprintf(buf+pos, len - pos, "Next boot RPRAM size %d MB\n", + nextboot_rpram_size); + + out = simple_read_from_buffer(user_buf, count, off, + buf, pos); + + free_page(addr); + return out; +} + +static ssize_t cn10k_rpram_config_write(struct file *f, const char __user *user_buf, + size_t count, loff_t *off) +{ + struct arm_smccc_res res; + unsigned long function_id, arg0, arg1; + int value; + ssize_t rc; + char buf[20]; + + if (count > sizeof(buf) - 1) + goto ret_err; + + if (copy_from_user(buf, user_buf, count)) + goto ret_err; + + buf[count] = 0; + + rc = kstrtouint(buf, 10, &value); + if (rc) + return rc; + + /* size should be multiples of 16 in MB */ + if ((value < MIN_USERDEF_PRESERVE_MEMSZ) || (value > MAX_USERDEF_PRESERVE_MEMSZ) + || (value % PRESERVE_MEMSZ_ALIGN)) + goto ret_err; + + nextboot_rpram_size = value; + + function_id = PLAT_OCTEONTX_PERSIST_DATA_COMMAND; + arg0 = UPDATE_USERDEF_PRESERVE_MEMSZ; + arg1 = nextboot_rpram_size; + + /* Secure firmware call to update the size of user defined memory */ + arm_smccc_smc(function_id, arg0, arg1, 0, 0, 0, 0, 0, &res); + return count; + +ret_err: + pr_err("Invalid size, max 1024, multiples of 16\n"); + return -EINVAL; +} + +static const struct file_operations rpram_config_fops = { + .read = cn10k_rpram_config_read, + .write = cn10k_rpram_config_write, +}; + +static const struct file_operations rpram_currentsz_ops = { + .read = cn10k_rpram_info_read, + .write = cn10k_rpram_info_write, +}; + +/* module init */ +static int __init cn10k_rpram_init(void) +{ + struct dentry *root, *entry; + struct device_node *parent, *node; + int ret; + + ret = octeontx_soc_check_smc(); + + if (ret != 2) { + pr_debug("%s: Not supported\n", __func__); + return -EPERM; + } + + parent = of_find_node_by_path("/reserved-memory"); + if (!parent) { + current_rpram_size = 0; + } else { + for_each_child_of_node(parent, node) { + const __be32 *prop; + u64 size; + + if (of_node_name_prefix(node, "user-def")) { + prop = of_get_property(node, "reg", NULL); + if (!prop) + break; + current_rpram_base = be32_to_cpu(prop[1]) | + (unsigned long long)be32_to_cpu(prop[0]) << 32; + size = be32_to_cpu(prop[3]) | + (unsigned long long)be32_to_cpu(prop[2]) << 32; + current_rpram_size = size / 1024 / 1024; + } + } + } + + /* root directory : rpram */ + root = debugfs_create_dir("rpram", NULL); + if (!root) { + pr_err("rpram debugfs creation failed\n"); + return -ENOMEM; + } + + preserve_mem_root = root; + nextboot_rpram_size = current_rpram_size; + + /* root/preserve_memsz_inMB creation */ + entry = debugfs_create_file("rpram_config_szMB", 0600, root, + &nextboot_rpram_size, &rpram_config_fops); + + if (!entry) { + pr_err("rpram->rpram_config_szMB debugfs file creation failed\n"); + debugfs_remove_recursive(preserve_mem_root); + preserve_mem_root = NULL; + return -ENOMEM; + } + + entry = debugfs_create_file("rpram_info", 0444, root, + ¤t_rpram_size, &rpram_currentsz_ops); + + if (!entry) { + pr_err("rpram->rpram_info debugfs file creation failed\n"); + debugfs_remove_recursive(preserve_mem_root); + preserve_mem_root = NULL; + return -ENOMEM; + } + + return 0; +} + +/* module exit */ +static void __exit cn10k_rpram_exit(void) +{ + if (preserve_mem_root != NULL) + debugfs_remove_recursive(preserve_mem_root); +} + +module_init(cn10k_rpram_init); +module_exit(cn10k_rpram_exit); + +MODULE_DESCRIPTION("Marvell driver for managing rpram"); +MODULE_AUTHOR("Jayanthi Annadurai <jannadurai@marvell.com>"); +MODULE_LICENSE("GPL"); |