linux/drivers/clk/socfpga/clk-pll-s10.c

148 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2017, Intel Corporation
*/
#include <linux/slab.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include "stratix10-clk.h"
#include "clk.h"
/* Clock Manager offsets */
#define CLK_MGR_PLL_CLK_SRC_SHIFT 16
#define CLK_MGR_PLL_CLK_SRC_MASK 0x3
/* PLL Clock enable bits */
#define SOCFPGA_PLL_POWER 0
#define SOCFPGA_PLL_RESET_MASK 0x2
#define SOCFPGA_PLL_REFDIV_MASK 0x00003F00
#define SOCFPGA_PLL_REFDIV_SHIFT 8
#define SOCFPGA_PLL_MDIV_MASK 0xFF000000
#define SOCFPGA_PLL_MDIV_SHIFT 24
#define SWCTRLBTCLKSEL_MASK 0x200
#define SWCTRLBTCLKSEL_SHIFT 9
#define SOCFPGA_BOOT_CLK "boot_clk"
#define to_socfpga_clk(p) container_of(p, struct socfpga_pll, hw.hw)
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 mdiv;
unsigned long refdiv;
unsigned long reg;
unsigned long long vco_freq;
/* read VCO1 reg for numerator and denominator */
reg = readl(socfpgaclk->hw.reg);
refdiv = (reg & SOCFPGA_PLL_REFDIV_MASK) >> SOCFPGA_PLL_REFDIV_SHIFT;
vco_freq = (unsigned long long)parent_rate / refdiv;
/* Read mdiv and fdiv from the fdbck register */
reg = readl(socfpgaclk->hw.reg + 0x4);
mdiv = (reg & SOCFPGA_PLL_MDIV_MASK) >> SOCFPGA_PLL_MDIV_SHIFT;
vco_freq = (unsigned long long)vco_freq * (mdiv + 6);
return (unsigned long)vco_freq;
}
static unsigned long clk_boot_clk_recalc_rate(struct clk_hw *hwclk,
unsigned long parent_rate)
{
struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
u32 div = 1;
div = ((readl(socfpgaclk->hw.reg) &
SWCTRLBTCLKSEL_MASK) >>
SWCTRLBTCLKSEL_SHIFT);
div += 1;
return parent_rate /= div;
}
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 u8 clk_boot_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 >> SWCTRLBTCLKSEL_SHIFT) &
SWCTRLBTCLKSEL_MASK;
}
static int clk_pll_prepare(struct clk_hw *hwclk)
{
struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
u32 reg;
/* Bring PLL out of reset */
reg = readl(socfpgaclk->hw.reg);
reg |= SOCFPGA_PLL_RESET_MASK;
writel(reg, socfpgaclk->hw.reg);
return 0;
}
static struct clk_ops clk_pll_ops = {
.recalc_rate = clk_pll_recalc_rate,
.get_parent = clk_pll_get_parent,
.prepare = clk_pll_prepare,
};
static struct clk_ops clk_boot_ops = {
.recalc_rate = clk_boot_clk_recalc_rate,
.get_parent = clk_boot_get_parent,
.prepare = clk_pll_prepare,
};
struct clk *s10_register_pll(const char *name, const char * const *parent_names,
u8 num_parents, unsigned long flags,
void __iomem *reg, unsigned long offset)
{
struct clk *clk;
struct socfpga_pll *pll_clk;
struct clk_init_data init;
pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
if (WARN_ON(!pll_clk))
return NULL;
pll_clk->hw.reg = reg + offset;
if (streq(name, SOCFPGA_BOOT_CLK))
init.ops = &clk_boot_ops;
else
init.ops = &clk_pll_ops;
init.name = name;
init.flags = flags;
init.num_parents = num_parents;
init.parent_names = parent_names;
pll_clk->hw.hw.init = &init;
pll_clk->hw.bit_idx = SOCFPGA_PLL_POWER;
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;
}
return clk;
}