linux/drivers/clk/pistachio/clk-pll.c

514 lines
14 KiB
C

/*
* Copyright (C) 2014 Google, Inc.
*
* 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.
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include "clk.h"
#define PLL_STATUS 0x0
#define PLL_STATUS_LOCK BIT(0)
#define PLL_CTRL1 0x4
#define PLL_CTRL1_REFDIV_SHIFT 0
#define PLL_CTRL1_REFDIV_MASK 0x3f
#define PLL_CTRL1_FBDIV_SHIFT 6
#define PLL_CTRL1_FBDIV_MASK 0xfff
#define PLL_INT_CTRL1_POSTDIV1_SHIFT 18
#define PLL_INT_CTRL1_POSTDIV1_MASK 0x7
#define PLL_INT_CTRL1_POSTDIV2_SHIFT 21
#define PLL_INT_CTRL1_POSTDIV2_MASK 0x7
#define PLL_INT_CTRL1_PD BIT(24)
#define PLL_INT_CTRL1_DSMPD BIT(25)
#define PLL_INT_CTRL1_FOUTPOSTDIVPD BIT(26)
#define PLL_INT_CTRL1_FOUTVCOPD BIT(27)
#define PLL_CTRL2 0x8
#define PLL_FRAC_CTRL2_FRAC_SHIFT 0
#define PLL_FRAC_CTRL2_FRAC_MASK 0xffffff
#define PLL_FRAC_CTRL2_POSTDIV1_SHIFT 24
#define PLL_FRAC_CTRL2_POSTDIV1_MASK 0x7
#define PLL_FRAC_CTRL2_POSTDIV2_SHIFT 27
#define PLL_FRAC_CTRL2_POSTDIV2_MASK 0x7
#define PLL_INT_CTRL2_BYPASS BIT(28)
#define PLL_CTRL3 0xc
#define PLL_FRAC_CTRL3_PD BIT(0)
#define PLL_FRAC_CTRL3_DACPD BIT(1)
#define PLL_FRAC_CTRL3_DSMPD BIT(2)
#define PLL_FRAC_CTRL3_FOUTPOSTDIVPD BIT(3)
#define PLL_FRAC_CTRL3_FOUT4PHASEPD BIT(4)
#define PLL_FRAC_CTRL3_FOUTVCOPD BIT(5)
#define PLL_CTRL4 0x10
#define PLL_FRAC_CTRL4_BYPASS BIT(28)
#define MIN_PFD 9600000UL
#define MIN_VCO_LA 400000000UL
#define MAX_VCO_LA 1600000000UL
#define MIN_VCO_FRAC_INT 600000000UL
#define MAX_VCO_FRAC_INT 1600000000UL
#define MIN_VCO_FRAC_FRAC 600000000UL
#define MAX_VCO_FRAC_FRAC 2400000000UL
#define MIN_OUTPUT_LA 8000000UL
#define MAX_OUTPUT_LA 1600000000UL
#define MIN_OUTPUT_FRAC 12000000UL
#define MAX_OUTPUT_FRAC 1600000000UL
/* Fractional PLL operating modes */
enum pll_mode {
PLL_MODE_FRAC,
PLL_MODE_INT,
};
struct pistachio_clk_pll {
struct clk_hw hw;
void __iomem *base;
struct pistachio_pll_rate_table *rates;
unsigned int nr_rates;
};
static inline u32 pll_readl(struct pistachio_clk_pll *pll, u32 reg)
{
return readl(pll->base + reg);
}
static inline void pll_writel(struct pistachio_clk_pll *pll, u32 val, u32 reg)
{
writel(val, pll->base + reg);
}
static inline void pll_lock(struct pistachio_clk_pll *pll)
{
while (!(pll_readl(pll, PLL_STATUS) & PLL_STATUS_LOCK))
cpu_relax();
}
static inline u64 do_div_round_closest(u64 dividend, u64 divisor)
{
dividend += divisor / 2;
return div64_u64(dividend, divisor);
}
static inline struct pistachio_clk_pll *to_pistachio_pll(struct clk_hw *hw)
{
return container_of(hw, struct pistachio_clk_pll, hw);
}
static inline enum pll_mode pll_frac_get_mode(struct clk_hw *hw)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u32 val;
val = pll_readl(pll, PLL_CTRL3) & PLL_FRAC_CTRL3_DSMPD;
return val ? PLL_MODE_INT : PLL_MODE_FRAC;
}
static inline void pll_frac_set_mode(struct clk_hw *hw, enum pll_mode mode)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u32 val;
val = pll_readl(pll, PLL_CTRL3);
if (mode == PLL_MODE_INT)
val |= PLL_FRAC_CTRL3_DSMPD | PLL_FRAC_CTRL3_DACPD;
else
val &= ~(PLL_FRAC_CTRL3_DSMPD | PLL_FRAC_CTRL3_DACPD);
pll_writel(pll, val, PLL_CTRL3);
}
static struct pistachio_pll_rate_table *
pll_get_params(struct pistachio_clk_pll *pll, unsigned long fref,
unsigned long fout)
{
unsigned int i;
for (i = 0; i < pll->nr_rates; i++) {
if (pll->rates[i].fref == fref && pll->rates[i].fout == fout)
return &pll->rates[i];
}
return NULL;
}
static long pll_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
unsigned int i;
for (i = 0; i < pll->nr_rates; i++) {
if (i > 0 && pll->rates[i].fref == *parent_rate &&
pll->rates[i].fout <= rate)
return pll->rates[i - 1].fout;
}
return pll->rates[0].fout;
}
static int pll_gf40lp_frac_enable(struct clk_hw *hw)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u32 val;
val = pll_readl(pll, PLL_CTRL3);
val &= ~(PLL_FRAC_CTRL3_PD | PLL_FRAC_CTRL3_FOUTPOSTDIVPD |
PLL_FRAC_CTRL3_FOUT4PHASEPD | PLL_FRAC_CTRL3_FOUTVCOPD);
pll_writel(pll, val, PLL_CTRL3);
val = pll_readl(pll, PLL_CTRL4);
val &= ~PLL_FRAC_CTRL4_BYPASS;
pll_writel(pll, val, PLL_CTRL4);
pll_lock(pll);
return 0;
}
static void pll_gf40lp_frac_disable(struct clk_hw *hw)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u32 val;
val = pll_readl(pll, PLL_CTRL3);
val |= PLL_FRAC_CTRL3_PD;
pll_writel(pll, val, PLL_CTRL3);
}
static int pll_gf40lp_frac_is_enabled(struct clk_hw *hw)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
return !(pll_readl(pll, PLL_CTRL3) & PLL_FRAC_CTRL3_PD);
}
static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
struct pistachio_pll_rate_table *params;
int enabled = pll_gf40lp_frac_is_enabled(hw);
u64 val, vco, old_postdiv1, old_postdiv2;
const char *name = clk_hw_get_name(hw);
if (rate < MIN_OUTPUT_FRAC || rate > MAX_OUTPUT_FRAC)
return -EINVAL;
params = pll_get_params(pll, parent_rate, rate);
if (!params || !params->refdiv)
return -EINVAL;
/* calculate vco */
vco = params->fref;
vco *= (params->fbdiv << 24) + params->frac;
vco = div64_u64(vco, params->refdiv << 24);
if (vco < MIN_VCO_FRAC_FRAC || vco > MAX_VCO_FRAC_FRAC)
pr_warn("%s: VCO %llu is out of range %lu..%lu\n", name, vco,
MIN_VCO_FRAC_FRAC, MAX_VCO_FRAC_FRAC);
val = div64_u64(params->fref, params->refdiv);
if (val < MIN_PFD)
pr_warn("%s: PFD %llu is too low (min %lu)\n",
name, val, MIN_PFD);
if (val > vco / 16)
pr_warn("%s: PFD %llu is too high (max %llu)\n",
name, val, vco / 16);
val = pll_readl(pll, PLL_CTRL1);
val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) |
(PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT));
val |= (params->refdiv << PLL_CTRL1_REFDIV_SHIFT) |
(params->fbdiv << PLL_CTRL1_FBDIV_SHIFT);
pll_writel(pll, val, PLL_CTRL1);
val = pll_readl(pll, PLL_CTRL2);
old_postdiv1 = (val >> PLL_FRAC_CTRL2_POSTDIV1_SHIFT) &
PLL_FRAC_CTRL2_POSTDIV1_MASK;
old_postdiv2 = (val >> PLL_FRAC_CTRL2_POSTDIV2_SHIFT) &
PLL_FRAC_CTRL2_POSTDIV2_MASK;
if (enabled &&
(params->postdiv1 != old_postdiv1 ||
params->postdiv2 != old_postdiv2))
pr_warn("%s: changing postdiv while PLL is enabled\n", name);
if (params->postdiv2 > params->postdiv1)
pr_warn("%s: postdiv2 should not exceed postdiv1\n", name);
val &= ~((PLL_FRAC_CTRL2_FRAC_MASK << PLL_FRAC_CTRL2_FRAC_SHIFT) |
(PLL_FRAC_CTRL2_POSTDIV1_MASK <<
PLL_FRAC_CTRL2_POSTDIV1_SHIFT) |
(PLL_FRAC_CTRL2_POSTDIV2_MASK <<
PLL_FRAC_CTRL2_POSTDIV2_SHIFT));
val |= (params->frac << PLL_FRAC_CTRL2_FRAC_SHIFT) |
(params->postdiv1 << PLL_FRAC_CTRL2_POSTDIV1_SHIFT) |
(params->postdiv2 << PLL_FRAC_CTRL2_POSTDIV2_SHIFT);
pll_writel(pll, val, PLL_CTRL2);
/* set operating mode */
if (params->frac)
pll_frac_set_mode(hw, PLL_MODE_FRAC);
else
pll_frac_set_mode(hw, PLL_MODE_INT);
if (enabled)
pll_lock(pll);
return 0;
}
static unsigned long pll_gf40lp_frac_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u64 val, prediv, fbdiv, frac, postdiv1, postdiv2, rate;
val = pll_readl(pll, PLL_CTRL1);
prediv = (val >> PLL_CTRL1_REFDIV_SHIFT) & PLL_CTRL1_REFDIV_MASK;
fbdiv = (val >> PLL_CTRL1_FBDIV_SHIFT) & PLL_CTRL1_FBDIV_MASK;
val = pll_readl(pll, PLL_CTRL2);
postdiv1 = (val >> PLL_FRAC_CTRL2_POSTDIV1_SHIFT) &
PLL_FRAC_CTRL2_POSTDIV1_MASK;
postdiv2 = (val >> PLL_FRAC_CTRL2_POSTDIV2_SHIFT) &
PLL_FRAC_CTRL2_POSTDIV2_MASK;
frac = (val >> PLL_FRAC_CTRL2_FRAC_SHIFT) & PLL_FRAC_CTRL2_FRAC_MASK;
/* get operating mode (int/frac) and calculate rate accordingly */
rate = parent_rate;
if (pll_frac_get_mode(hw) == PLL_MODE_FRAC)
rate *= (fbdiv << 24) + frac;
else
rate *= (fbdiv << 24);
rate = do_div_round_closest(rate, (prediv * postdiv1 * postdiv2) << 24);
return rate;
}
static struct clk_ops pll_gf40lp_frac_ops = {
.enable = pll_gf40lp_frac_enable,
.disable = pll_gf40lp_frac_disable,
.is_enabled = pll_gf40lp_frac_is_enabled,
.recalc_rate = pll_gf40lp_frac_recalc_rate,
.round_rate = pll_round_rate,
.set_rate = pll_gf40lp_frac_set_rate,
};
static struct clk_ops pll_gf40lp_frac_fixed_ops = {
.enable = pll_gf40lp_frac_enable,
.disable = pll_gf40lp_frac_disable,
.is_enabled = pll_gf40lp_frac_is_enabled,
.recalc_rate = pll_gf40lp_frac_recalc_rate,
};
static int pll_gf40lp_laint_enable(struct clk_hw *hw)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u32 val;
val = pll_readl(pll, PLL_CTRL1);
val &= ~(PLL_INT_CTRL1_PD |
PLL_INT_CTRL1_FOUTPOSTDIVPD | PLL_INT_CTRL1_FOUTVCOPD);
pll_writel(pll, val, PLL_CTRL1);
val = pll_readl(pll, PLL_CTRL2);
val &= ~PLL_INT_CTRL2_BYPASS;
pll_writel(pll, val, PLL_CTRL2);
pll_lock(pll);
return 0;
}
static void pll_gf40lp_laint_disable(struct clk_hw *hw)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u32 val;
val = pll_readl(pll, PLL_CTRL1);
val |= PLL_INT_CTRL1_PD;
pll_writel(pll, val, PLL_CTRL1);
}
static int pll_gf40lp_laint_is_enabled(struct clk_hw *hw)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
return !(pll_readl(pll, PLL_CTRL1) & PLL_INT_CTRL1_PD);
}
static int pll_gf40lp_laint_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
struct pistachio_pll_rate_table *params;
int enabled = pll_gf40lp_laint_is_enabled(hw);
u32 val, vco, old_postdiv1, old_postdiv2;
const char *name = clk_hw_get_name(hw);
if (rate < MIN_OUTPUT_LA || rate > MAX_OUTPUT_LA)
return -EINVAL;
params = pll_get_params(pll, parent_rate, rate);
if (!params || !params->refdiv)
return -EINVAL;
vco = div_u64(params->fref * params->fbdiv, params->refdiv);
if (vco < MIN_VCO_LA || vco > MAX_VCO_LA)
pr_warn("%s: VCO %u is out of range %lu..%lu\n", name, vco,
MIN_VCO_LA, MAX_VCO_LA);
val = div_u64(params->fref, params->refdiv);
if (val < MIN_PFD)
pr_warn("%s: PFD %u is too low (min %lu)\n",
name, val, MIN_PFD);
if (val > vco / 16)
pr_warn("%s: PFD %u is too high (max %u)\n",
name, val, vco / 16);
val = pll_readl(pll, PLL_CTRL1);
old_postdiv1 = (val >> PLL_INT_CTRL1_POSTDIV1_SHIFT) &
PLL_INT_CTRL1_POSTDIV1_MASK;
old_postdiv2 = (val >> PLL_INT_CTRL1_POSTDIV2_SHIFT) &
PLL_INT_CTRL1_POSTDIV2_MASK;
if (enabled &&
(params->postdiv1 != old_postdiv1 ||
params->postdiv2 != old_postdiv2))
pr_warn("%s: changing postdiv while PLL is enabled\n", name);
if (params->postdiv2 > params->postdiv1)
pr_warn("%s: postdiv2 should not exceed postdiv1\n", name);
val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) |
(PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT) |
(PLL_INT_CTRL1_POSTDIV1_MASK << PLL_INT_CTRL1_POSTDIV1_SHIFT) |
(PLL_INT_CTRL1_POSTDIV2_MASK << PLL_INT_CTRL1_POSTDIV2_SHIFT));
val |= (params->refdiv << PLL_CTRL1_REFDIV_SHIFT) |
(params->fbdiv << PLL_CTRL1_FBDIV_SHIFT) |
(params->postdiv1 << PLL_INT_CTRL1_POSTDIV1_SHIFT) |
(params->postdiv2 << PLL_INT_CTRL1_POSTDIV2_SHIFT);
pll_writel(pll, val, PLL_CTRL1);
if (enabled)
pll_lock(pll);
return 0;
}
static unsigned long pll_gf40lp_laint_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
u32 val, prediv, fbdiv, postdiv1, postdiv2;
u64 rate = parent_rate;
val = pll_readl(pll, PLL_CTRL1);
prediv = (val >> PLL_CTRL1_REFDIV_SHIFT) & PLL_CTRL1_REFDIV_MASK;
fbdiv = (val >> PLL_CTRL1_FBDIV_SHIFT) & PLL_CTRL1_FBDIV_MASK;
postdiv1 = (val >> PLL_INT_CTRL1_POSTDIV1_SHIFT) &
PLL_INT_CTRL1_POSTDIV1_MASK;
postdiv2 = (val >> PLL_INT_CTRL1_POSTDIV2_SHIFT) &
PLL_INT_CTRL1_POSTDIV2_MASK;
rate *= fbdiv;
rate = do_div_round_closest(rate, prediv * postdiv1 * postdiv2);
return rate;
}
static struct clk_ops pll_gf40lp_laint_ops = {
.enable = pll_gf40lp_laint_enable,
.disable = pll_gf40lp_laint_disable,
.is_enabled = pll_gf40lp_laint_is_enabled,
.recalc_rate = pll_gf40lp_laint_recalc_rate,
.round_rate = pll_round_rate,
.set_rate = pll_gf40lp_laint_set_rate,
};
static struct clk_ops pll_gf40lp_laint_fixed_ops = {
.enable = pll_gf40lp_laint_enable,
.disable = pll_gf40lp_laint_disable,
.is_enabled = pll_gf40lp_laint_is_enabled,
.recalc_rate = pll_gf40lp_laint_recalc_rate,
};
static struct clk *pll_register(const char *name, const char *parent_name,
unsigned long flags, void __iomem *base,
enum pistachio_pll_type type,
struct pistachio_pll_rate_table *rates,
unsigned int nr_rates)
{
struct pistachio_clk_pll *pll;
struct clk_init_data init;
struct clk *clk;
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
init.name = name;
init.flags = flags | CLK_GET_RATE_NOCACHE;
init.parent_names = &parent_name;
init.num_parents = 1;
switch (type) {
case PLL_GF40LP_FRAC:
if (rates)
init.ops = &pll_gf40lp_frac_ops;
else
init.ops = &pll_gf40lp_frac_fixed_ops;
break;
case PLL_GF40LP_LAINT:
if (rates)
init.ops = &pll_gf40lp_laint_ops;
else
init.ops = &pll_gf40lp_laint_fixed_ops;
break;
default:
pr_err("Unrecognized PLL type %u\n", type);
kfree(pll);
return ERR_PTR(-EINVAL);
}
pll->hw.init = &init;
pll->base = base;
pll->rates = rates;
pll->nr_rates = nr_rates;
clk = clk_register(NULL, &pll->hw);
if (IS_ERR(clk))
kfree(pll);
return clk;
}
void pistachio_clk_register_pll(struct pistachio_clk_provider *p,
struct pistachio_pll *pll,
unsigned int num)
{
struct clk *clk;
unsigned int i;
for (i = 0; i < num; i++) {
clk = pll_register(pll[i].name, pll[i].parent,
0, p->base + pll[i].reg_base,
pll[i].type, pll[i].rates,
pll[i].nr_rates);
p->clk_data.clks[pll[i].id] = clk;
}
}