tegrakernel/kernel/nvidia/drivers/misc/mods/mods_clock.c

570 lines
12 KiB
C

/*
* mods_clock.c - This file is part of NVIDIA MODS kernel driver.
*
* Copyright (c) 2011-2017, NVIDIA CORPORATION. All rights reserved.
*
* NVIDIA MODS kernel driver 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.
*
* NVIDIA MODS kernel driver is distributed in the hope that 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.
*
* You should have received a copy of the GNU General Public License
* along with NVIDIA MODS kernel driver.
* If not, see <http://www.gnu.org/licenses/>.
*/
#include "mods_internal.h"
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/reset.h>
#define ARBITRARY_MAX_CLK_FREQ 3500000000
static struct list_head mods_clock_handles;
static spinlock_t mods_clock_lock;
static u32 last_handle;
struct clock_entry {
struct clk *pclk;
u32 handle;
struct list_head list;
};
static struct device_node *find_clocks_node(const char *name)
{
const char *node_name = "mods-simple-bus";
struct device_node *pp = NULL, *np = NULL;
pp = of_find_node_by_name(NULL, node_name);
if (!pp) {
mods_error_printk("'mods-simple-bus' node not found in device tree\n");
return pp;
}
np = of_get_child_by_name(pp, name);
return np;
}
void mods_init_clock_api(void)
{
const char *okay_value = "okay";
struct device_node *mods_np = 0;
struct property *pp = 0;
int size_value = 0;
mods_np = find_clocks_node("mods-clocks");
if (!mods_np) {
mods_error_printk("'mods-clocks' node not found in device tree\n");
goto err;
}
pp = of_find_property(mods_np, "status", NULL);
if (IS_ERR(pp)) {
mods_error_printk("'status' prop not found in 'mods-clocks' node.");
goto err;
}
/* if status is 'okay', then skip updating property */
if (of_device_is_available(mods_np))
goto err;
size_value = strlen(okay_value) + 1;
pp->value = kmalloc(size_value, GFP_KERNEL);
strncpy(pp->value, okay_value, size_value);
pp->length = size_value;
err:
of_node_put(mods_np);
spin_lock_init(&mods_clock_lock);
INIT_LIST_HEAD(&mods_clock_handles);
last_handle = 0;
}
void mods_shutdown_clock_api(void)
{
struct list_head *head = &mods_clock_handles;
struct list_head *iter;
struct list_head *tmp;
spin_lock(&mods_clock_lock);
list_for_each_safe(iter, tmp, head) {
struct clock_entry *entry
= list_entry(iter, struct clock_entry, list);
list_del(iter);
kfree(entry);
}
spin_unlock(&mods_clock_lock);
}
static u32 mods_get_clock_handle(struct clk *pclk)
{
struct list_head *head = &mods_clock_handles;
struct list_head *iter;
struct clock_entry *entry = 0;
u32 handle = 0;
spin_lock(&mods_clock_lock);
list_for_each(iter, head) {
struct clock_entry *cur
= list_entry(iter, struct clock_entry, list);
if (cur->pclk == pclk) {
entry = cur;
handle = cur->handle;
break;
}
}
if (!entry) {
entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
if (!unlikely(!entry)) {
entry->pclk = pclk;
entry->handle = ++last_handle;
handle = entry->handle;
list_add(&entry->list, &mods_clock_handles);
}
}
spin_unlock(&mods_clock_lock);
return handle;
}
static struct clk *mods_get_clock(u32 handle)
{
struct list_head *head = &mods_clock_handles;
struct list_head *iter;
struct clk *pclk = 0;
spin_lock(&mods_clock_lock);
list_for_each(iter, head) {
struct clock_entry *entry
= list_entry(iter, struct clock_entry, list);
if (entry->handle == handle) {
pclk = entry->pclk;
break;
}
}
spin_unlock(&mods_clock_lock);
return pclk;
}
int esc_mods_get_clock_handle(struct file *pfile,
struct MODS_GET_CLOCK_HANDLE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
struct device_node *mods_np = 0;
struct property *pp = 0;
LOG_ENT();
mods_np = find_clocks_node("mods-clocks");
if (!mods_np || !of_device_is_available(mods_np)) {
mods_error_printk("'mods-clocks' node not found in device tree\n");
goto err;
}
pp = of_find_property(mods_np, "clock-names", NULL);
if (IS_ERR(pp)) {
mods_error_printk(
"No 'clock-names' prop in 'mods-clocks' node for dev %s\n",
p->controller_name);
goto err;
}
pclk = of_clk_get_by_name(mods_np, p->controller_name);
if (IS_ERR(pclk))
mods_error_printk("clk (%s) not found\n", p->controller_name);
else {
p->clock_handle = mods_get_clock_handle(pclk);
ret = OK;
}
err:
of_node_put(mods_np);
LOG_EXT();
return ret;
}
int esc_mods_set_clock_rate(struct file *pfile, struct MODS_CLOCK_RATE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
ret = clk_set_rate(pclk, p->clock_rate_hz);
if (ret) {
mods_error_printk(
"unable to set rate %lluHz on clock 0x%x\n",
p->clock_rate_hz, p->clock_handle);
} else {
mods_debug_printk(DEBUG_CLOCK,
"successfuly set rate %lluHz on clock 0x%x\n",
p->clock_rate_hz, p->clock_handle);
}
}
LOG_EXT();
return ret;
}
int esc_mods_get_clock_rate(struct file *pfile, struct MODS_CLOCK_RATE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
p->clock_rate_hz = clk_get_rate(pclk);
mods_debug_printk(DEBUG_CLOCK, "clock 0x%x has rate %lluHz\n",
p->clock_handle, p->clock_rate_hz);
ret = OK;
}
LOG_EXT();
return ret;
}
int esc_mods_get_clock_max_rate(struct file *pfile, struct MODS_CLOCK_RATE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
long rate = clk_round_rate(pclk, ARBITRARY_MAX_CLK_FREQ);
p->clock_rate_hz = rate < 0 ? ARBITRARY_MAX_CLK_FREQ
: (unsigned long)rate;
mods_debug_printk(DEBUG_CLOCK,
"clock 0x%x has max rate %lluHz\n",
p->clock_handle, p->clock_rate_hz);
ret = OK;
}
LOG_EXT();
return ret;
}
int esc_mods_set_clock_max_rate(struct file *pfile, struct MODS_CLOCK_RATE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
#if defined(CONFIG_TEGRA_CLOCK_DEBUG_FUNC)
ret = tegra_clk_set_max(pclk, p->clock_rate_hz);
if (ret) {
mods_error_printk(
"unable to override max clock rate %lluHz on clock 0x%x\n",
p->clock_rate_hz, p->clock_handle);
} else {
mods_debug_printk(DEBUG_CLOCK,
"successfuly set max rate %lluHz on clock 0x%x\n",
p->clock_rate_hz, p->clock_handle);
}
#else
mods_error_printk("unable to override max clock rate\n");
mods_error_printk(
"reconfigure kernel with CONFIG_TEGRA_CLOCK_DEBUG_FUNC=y\n");
ret = -EINVAL;
#endif
}
LOG_EXT();
return ret;
}
int esc_mods_set_clock_parent(struct file *pfile, struct MODS_CLOCK_PARENT *p)
{
struct clk *pclk = 0;
struct clk *pparent = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
pparent = mods_get_clock(p->clock_parent_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else if (!pparent) {
mods_error_printk("unrecognized parent clock handle: 0x%x\n",
p->clock_parent_handle);
} else {
ret = clk_set_parent(pclk, pparent);
if (ret) {
mods_error_printk(
"unable to make clock 0x%x parent of clock 0x%x\n",
p->clock_parent_handle, p->clock_handle);
} else {
mods_debug_printk(DEBUG_CLOCK,
"successfuly made clock 0x%x parent of clock 0x%x\n",
p->clock_parent_handle, p->clock_handle);
}
}
LOG_EXT();
return ret;
}
int esc_mods_get_clock_parent(struct file *pfile, struct MODS_CLOCK_PARENT *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
struct clk *pparent = clk_get_parent(pclk);
p->clock_parent_handle = mods_get_clock_handle(pparent);
mods_debug_printk(DEBUG_CLOCK,
"clock 0x%x is parent of clock 0x%x\n",
p->clock_parent_handle, p->clock_handle);
ret = OK;
}
LOG_EXT();
return ret;
}
int esc_mods_enable_clock(struct file *pfile, struct MODS_CLOCK_HANDLE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
ret = clk_prepare(pclk);
if (ret) {
mods_error_printk(
"unable to prepare clock 0x%x before enabling\n",
p->clock_handle);
}
ret = clk_enable(pclk);
if (ret) {
mods_error_printk("failed to enable clock 0x%x\n",
p->clock_handle);
} else {
mods_debug_printk(DEBUG_CLOCK, "clock 0x%x enabled\n",
p->clock_handle);
}
}
LOG_EXT();
return ret;
}
int esc_mods_disable_clock(struct file *pfile, struct MODS_CLOCK_HANDLE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
clk_disable(pclk);
clk_unprepare(pclk);
mods_debug_printk(DEBUG_CLOCK, "clock 0x%x disabled\n",
p->clock_handle);
ret = OK;
}
LOG_EXT();
return ret;
}
int esc_mods_is_clock_enabled(struct file *pfile, struct MODS_CLOCK_ENABLED *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
p->enable_count = (u32)__clk_is_enabled(pclk);
mods_debug_printk(DEBUG_CLOCK, "clock 0x%x enable count is %u\n",
p->clock_handle, p->enable_count);
ret = OK;
}
LOG_EXT();
return ret;
}
int esc_mods_clock_reset_assert(struct file *pfile,
struct MODS_CLOCK_HANDLE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
const char *clk_name = 0;
struct reset_control *prst = 0;
struct device_node *mods_np = 0;
struct property *pp = 0;
mods_np = find_clocks_node("mods-clocks");
if (!mods_np || !of_device_is_available(mods_np)) {
mods_error_printk("'mods-clocks' node not found in DTB\n");
goto err;
}
pp = of_find_property(mods_np, "reset-names", NULL);
if (IS_ERR(pp)) {
mods_error_printk(
"No 'reset-names' prop in 'mods-clocks' node for dev %s\n",
__clk_get_name(pclk));
goto err;
}
clk_name = __clk_get_name(pclk);
prst = of_reset_control_get(mods_np, clk_name);
if (IS_ERR(prst)) {
mods_error_printk("reset device %s not found\n",
clk_name);
goto err;
}
ret = reset_control_assert(prst);
if (ret) {
mods_error_printk("failed to assert reset on '%s'\n",
clk_name);
} else {
mods_debug_printk(DEBUG_CLOCK, "asserted reset on '%s'",
clk_name);
}
err:
of_node_put(mods_np);
}
LOG_EXT();
return ret;
}
int esc_mods_clock_reset_deassert(struct file *pfile,
struct MODS_CLOCK_HANDLE *p)
{
struct clk *pclk = 0;
int ret = -EINVAL;
LOG_ENT();
pclk = mods_get_clock(p->clock_handle);
if (!pclk) {
mods_error_printk("unrecognized clock handle: 0x%x\n",
p->clock_handle);
} else {
const char *clk_name = 0;
struct reset_control *prst = 0;
struct device_node *mods_np = 0;
struct property *pp = 0;
mods_np = find_clocks_node("mods-clocks");
if (!mods_np || !of_device_is_available(mods_np)) {
mods_error_printk("'mods-clocks' node not found in DTB\n");
goto err;
}
pp = of_find_property(mods_np, "reset-names", NULL);
if (IS_ERR(pp)) {
mods_error_printk(
"No 'reset-names' prop in 'mods-clocks' node for dev %s\n",
__clk_get_name(pclk));
goto err;
}
clk_name = __clk_get_name(pclk);
prst = of_reset_control_get(mods_np, clk_name);
if (IS_ERR(prst)) {
mods_error_printk(
"reset device %s not found\n", clk_name);
goto err;
}
ret = reset_control_deassert(prst);
if (ret) {
mods_error_printk("failed to assert reset on '%s'\n",
clk_name);
} else {
mods_debug_printk(DEBUG_CLOCK, "deasserted reset on '%s'",
clk_name);
}
err:
of_node_put(mods_np);
}
LOG_EXT();
return ret;
}