OSHW-DEIMOS/SOFTWARE/A64-TERES/linux-a64/drivers/clk/versatile/clk-vexpress-spc.c
Dimitar Gamishev f9b0e7a283 linux
2017-10-13 14:07:04 +03:00

132 lines
2.9 KiB
C

/*
* Copyright (C) 2012 ARM Limited
* Copyright (C) 2012 Linaro
*
* Author: Viresh Kumar <viresh.kumar@linaro.org>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
/* SPC clock programming interface for Vexpress cpus */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/vexpress.h>
struct clk_spc {
struct clk_hw hw;
spinlock_t *lock;
int cluster;
};
#define to_clk_spc(spc) container_of(spc, struct clk_spc, hw)
static unsigned long spc_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_spc *spc = to_clk_spc(hw);
u32 freq;
if (vexpress_spc_get_performance(spc->cluster, &freq)) {
return -EIO;
pr_err("%s: Failed", __func__);
}
return freq * 1000;
}
static long spc_round_rate(struct clk_hw *hw, unsigned long drate,
unsigned long *parent_rate)
{
return drate;
}
static int spc_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_spc *spc = to_clk_spc(hw);
return vexpress_spc_set_performance(spc->cluster, rate / 1000);
}
static struct clk_ops clk_spc_ops = {
.recalc_rate = spc_recalc_rate,
.round_rate = spc_round_rate,
.set_rate = spc_set_rate,
};
struct clk *vexpress_clk_register_spc(const char *name, int cluster_id)
{
struct clk_init_data init;
struct clk_spc *spc;
struct clk *clk;
if (!name) {
pr_err("Invalid name passed");
return ERR_PTR(-EINVAL);
}
spc = kzalloc(sizeof(*spc), GFP_KERNEL);
if (!spc) {
pr_err("could not allocate spc clk\n");
return ERR_PTR(-ENOMEM);
}
spc->hw.init = &init;
spc->cluster = cluster_id;
init.name = name;
init.ops = &clk_spc_ops;
init.flags = CLK_IS_ROOT | CLK_GET_RATE_NOCACHE;
init.num_parents = 0;
clk = clk_register(NULL, &spc->hw);
if (!IS_ERR_OR_NULL(clk))
return clk;
pr_err("clk register failed\n");
kfree(spc);
return NULL;
}
#if defined(CONFIG_OF)
void __init vexpress_clk_of_register_spc(void)
{
char name[14] = "cpu-cluster.X";
struct device_node *node = NULL;
struct clk *clk;
const u32 *val;
int cluster_id = 0, len;
if (!of_find_compatible_node(NULL, NULL, "arm,vexpress-spc")) {
pr_debug("%s: No SPC found, Exiting!!\n", __func__);
return;
}
while ((node = of_find_node_by_name(node, "cluster"))) {
val = of_get_property(node, "reg", &len);
if (val && len == 4)
cluster_id = be32_to_cpup(val);
name[12] = cluster_id + '0';
clk = vexpress_clk_register_spc(name, cluster_id);
if (IS_ERR(clk))
return;
pr_debug("Registered clock '%s'\n", name);
clk_register_clkdev(clk, NULL, name);
}
}
CLK_OF_DECLARE(spc, "arm,vexpress-spc", vexpress_clk_of_register_spc);
#endif