/*
* Copyright (C) 2015 Altera Corporation. All rights reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/slab.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include "clk.h"
/* Clock Manager offsets */
#define CLK_MGR_PLL_CLK_SRC_SHIFT 8
#define CLK_MGR_PLL_CLK_SRC_MASK 0x3
/* Clock bypass bits */
#define SOCFPGA_PLL_BG_PWRDWN 0
#define SOCFPGA_PLL_PWR_DOWN 1
#define SOCFPGA_PLL_EXT_ENA 2
#define SOCFPGA_PLL_DIVF_MASK 0x00001FFF
#define SOCFPGA_PLL_DIVF_SHIFT 0
#define SOCFPGA_PLL_DIVQ_MASK 0x003F0000
#define SOCFPGA_PLL_DIVQ_SHIFT 16
#define SOCFGPA_MAX_PARENTS 5
#define SOCFPGA_MAIN_PLL_CLK "main_pll"
#define SOCFPGA_PERIP_PLL_CLK "periph_pll"
#define to_socfpga_clk(p) container_of(p, struct socfpga_pll, hw.hw)
void __iomem *clk_mgr_a10_base_addr;
static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
unsigned long parent_rate)
{
struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
unsigned long divf, divq, reg;
unsigned long long vco_freq;
/* read VCO1 reg for numerator and denominator */
reg = readl(socfpgaclk->hw.reg + 0x4);
divf = (reg & SOCFPGA_PLL_DIVF_MASK) >> SOCFPGA_PLL_DIVF_SHIFT;
divq = (reg & SOCFPGA_PLL_DIVQ_MASK) >> SOCFPGA_PLL_DIVQ_SHIFT;
vco_freq = (unsigned long long)parent_rate * (divf + 1);
do_div(vco_freq, (1 + divq));
return (unsigned long)vco_freq;
}
static u8 clk_pll_get_parent(struct clk_hw *hwclk)
{
struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
u32 pll_src;
pll_src = readl(socfpgaclk->hw.reg);
return (pll_src >> CLK_MGR_PLL_CLK_SRC_SHIFT) &
CLK_MGR_PLL_CLK_SRC_MASK;
}
static struct clk_ops clk_pll_ops = {
.recalc_rate = clk_pll_recalc_rate,
.get_parent = clk_pll_get_parent,
};
static struct clk * __init __socfpga_pll_init(struct device_node *node,
const struct clk_ops *ops)
{
u32 reg;
struct clk *clk;
struct socfpga_pll *pll_clk;
const char *clk_name = node->name;
const char *parent_name[SOCFGPA_MAX_PARENTS];
struct clk_init_data init;
struct device_node *clkmgr_np;
int rc;
int i = 0;
of_property_read_u32(node, "reg", ®);
pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
if (WARN_ON(!pll_clk))
return NULL;
clkmgr_np = of_find_compatible_node(NULL, NULL, "altr,clk-mgr");
clk_mgr_a10_base_addr = of_iomap(clkmgr_np, 0);
BUG_ON(!clk_mgr_a10_base_addr);
pll_clk->hw.reg = clk_mgr_a10_base_addr + reg;
of_property_read_string(node, "clock-output-names", &clk_name);
init.name = clk_name;
init.ops = ops;
init.flags = 0;
while (i < SOCFGPA_MAX_PARENTS && (parent_name[i] =
of_clk_get_parent_name(node, i)) != NULL)
i++;
init.num_parents = i;
init.parent_names = parent_name;
pll_clk->hw.hw.init = &init;
pll_clk->hw.bit_idx = SOCFPGA_PLL_EXT_ENA;
clk_pll_ops.enable = clk_gate_ops.enable;
clk_pll_ops.disable = clk_gate_ops.disable;
clk = clk_register(NULL, &pll_clk->hw.hw);
if (WARN_ON(IS_ERR(clk))) {
kfree(pll_clk);
return NULL;
}
rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
return clk;
}
void __init socfpga_a10_pll_init(struct device_node *node)
{
__socfpga_pll_init(node, &clk_pll_ops);
}