linux-zen-desktop/drivers/clk/socfpga/clk-gate-a10.c

122 lines
2.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 Altera Corporation. All rights reserved
*/
#include <linux/slab.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include "clk.h"
#define streq(a, b) (strcmp((a), (b)) == 0)
#define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw)
/* SDMMC Group for System Manager defines */
#define SYSMGR_SDMMCGRP_CTRL_OFFSET 0x28
static unsigned long socfpga_gate_clk_recalc_rate(struct clk_hw *hwclk,
unsigned long parent_rate)
{
struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
u32 div = 1, val;
if (socfpgaclk->fixed_div)
div = socfpgaclk->fixed_div;
else if (socfpgaclk->div_reg) {
val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
val &= GENMASK(socfpgaclk->width - 1, 0);
div = (1 << val);
}
return parent_rate / div;
}
static struct clk_ops gateclk_ops = {
.recalc_rate = socfpga_gate_clk_recalc_rate,
};
static void __init __socfpga_gate_init(struct device_node *node,
const struct clk_ops *ops)
{
u32 clk_gate[2];
u32 div_reg[3];
u32 fixed_div;
struct clk_hw *hw_clk;
struct socfpga_gate_clk *socfpga_clk;
const char *clk_name = node->name;
const char *parent_name[SOCFPGA_MAX_PARENTS];
struct clk_init_data init;
int rc;
socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
if (WARN_ON(!socfpga_clk))
return;
rc = of_property_read_u32_array(node, "clk-gate", clk_gate, 2);
if (rc)
clk_gate[0] = 0;
if (clk_gate[0]) {
socfpga_clk->hw.reg = clk_mgr_a10_base_addr + clk_gate[0];
socfpga_clk->hw.bit_idx = clk_gate[1];
gateclk_ops.enable = clk_gate_ops.enable;
gateclk_ops.disable = clk_gate_ops.disable;
}
rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
if (rc)
socfpga_clk->fixed_div = 0;
else
socfpga_clk->fixed_div = fixed_div;
rc = of_property_read_u32_array(node, "div-reg", div_reg, 3);
if (!rc) {
socfpga_clk->div_reg = clk_mgr_a10_base_addr + div_reg[0];
socfpga_clk->shift = div_reg[1];
socfpga_clk->width = div_reg[2];
} else {
socfpga_clk->div_reg = NULL;
}
of_property_read_string(node, "clock-output-names", &clk_name);
init.name = clk_name;
init.ops = ops;
init.flags = 0;
init.num_parents = of_clk_parent_fill(node, parent_name, SOCFPGA_MAX_PARENTS);
init.parent_names = parent_name;
socfpga_clk->hw.hw.init = &init;
hw_clk = &socfpga_clk->hw.hw;
rc = clk_hw_register(NULL, hw_clk);
if (rc) {
pr_err("Could not register clock:%s\n", clk_name);
goto err_clk_hw_register;
}
rc = of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw_clk);
if (rc) {
pr_err("Could not register clock provider for node:%s\n",
clk_name);
goto err_of_clk_add_hw_provider;
}
return;
err_of_clk_add_hw_provider:
clk_hw_unregister(hw_clk);
err_clk_hw_register:
kfree(socfpga_clk);
}
void __init socfpga_a10_gate_init(struct device_node *node)
{
__socfpga_gate_init(node, &gateclk_ops);
}