mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-09-08 05:43:21 +09:00
269 lines
6.3 KiB
C
269 lines
6.3 KiB
C
![]() |
// SPDX-License-Identifier: GPL-2.0+
|
||
|
/*
|
||
|
* TI DPLL clock support
|
||
|
*
|
||
|
* Copyright (C) 2020 Dario Binacchi <dariobin@libero.it>
|
||
|
*
|
||
|
* Loosely based on Linux kernel drivers/clk/ti/dpll.c
|
||
|
*/
|
||
|
|
||
|
#include <common.h>
|
||
|
#include <clk.h>
|
||
|
#include <clk-uclass.h>
|
||
|
#include <div64.h>
|
||
|
#include <dm.h>
|
||
|
#include <dm/device_compat.h>
|
||
|
#include <hang.h>
|
||
|
#include <asm/arch/clock.h>
|
||
|
#include <asm/arch/sys_proto.h>
|
||
|
#include <asm/io.h>
|
||
|
|
||
|
struct clk_ti_am3_dpll_drv_data {
|
||
|
ulong max_rate;
|
||
|
};
|
||
|
|
||
|
struct clk_ti_am3_dpll_priv {
|
||
|
fdt_addr_t clkmode_reg;
|
||
|
fdt_addr_t idlest_reg;
|
||
|
fdt_addr_t clksel_reg;
|
||
|
struct clk clk_bypass;
|
||
|
struct clk clk_ref;
|
||
|
u16 last_rounded_mult;
|
||
|
u8 last_rounded_div;
|
||
|
ulong max_rate;
|
||
|
};
|
||
|
|
||
|
static ulong clk_ti_am3_dpll_round_rate(struct clk *clk, ulong rate)
|
||
|
{
|
||
|
struct clk_ti_am3_dpll_priv *priv = dev_get_priv(clk->dev);
|
||
|
ulong ret, ref_rate, r;
|
||
|
int m, d, err_min, err;
|
||
|
int mult = INT_MAX, div = INT_MAX;
|
||
|
|
||
|
if (priv->max_rate && rate > priv->max_rate) {
|
||
|
dev_warn(clk->dev, "%ld is to high a rate, lowered to %ld\n",
|
||
|
rate, priv->max_rate);
|
||
|
rate = priv->max_rate;
|
||
|
}
|
||
|
|
||
|
ret = -EFAULT;
|
||
|
err = rate;
|
||
|
err_min = rate;
|
||
|
ref_rate = clk_get_rate(&priv->clk_ref);
|
||
|
for (d = 1; err_min && d <= 128; d++) {
|
||
|
for (m = 2; m <= 2047; m++) {
|
||
|
r = (ref_rate * m) / d;
|
||
|
err = abs(r - rate);
|
||
|
if (err < err_min) {
|
||
|
err_min = err;
|
||
|
ret = r;
|
||
|
mult = m;
|
||
|
div = d;
|
||
|
|
||
|
if (err == 0)
|
||
|
break;
|
||
|
} else if (r > rate) {
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
priv->last_rounded_mult = mult;
|
||
|
priv->last_rounded_div = div;
|
||
|
dev_dbg(clk->dev, "rate=%ld, best_rate=%ld, mult=%d, div=%d\n", rate,
|
||
|
ret, mult, div);
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
static ulong clk_ti_am3_dpll_set_rate(struct clk *clk, ulong rate)
|
||
|
{
|
||
|
struct clk_ti_am3_dpll_priv *priv = dev_get_priv(clk->dev);
|
||
|
u32 v;
|
||
|
ulong round_rate;
|
||
|
|
||
|
round_rate = clk_ti_am3_dpll_round_rate(clk, rate);
|
||
|
if (IS_ERR_VALUE(round_rate))
|
||
|
return round_rate;
|
||
|
|
||
|
v = readl(priv->clksel_reg);
|
||
|
|
||
|
/* enter bypass mode */
|
||
|
clrsetbits_le32(priv->clkmode_reg, CM_CLKMODE_DPLL_DPLL_EN_MASK,
|
||
|
DPLL_EN_MN_BYPASS << CM_CLKMODE_DPLL_EN_SHIFT);
|
||
|
|
||
|
/* wait for bypass mode */
|
||
|
if (!wait_on_value(ST_DPLL_CLK_MASK, 0,
|
||
|
(void *)priv->idlest_reg, LDELAY))
|
||
|
dev_err(clk->dev, "failed bypassing dpll\n");
|
||
|
|
||
|
/* set M & N */
|
||
|
v &= ~CM_CLKSEL_DPLL_M_MASK;
|
||
|
v |= (priv->last_rounded_mult << CM_CLKSEL_DPLL_M_SHIFT) &
|
||
|
CM_CLKSEL_DPLL_M_MASK;
|
||
|
|
||
|
v &= ~CM_CLKSEL_DPLL_N_MASK;
|
||
|
v |= ((priv->last_rounded_div - 1) << CM_CLKSEL_DPLL_N_SHIFT) &
|
||
|
CM_CLKSEL_DPLL_N_MASK;
|
||
|
|
||
|
writel(v, priv->clksel_reg);
|
||
|
|
||
|
/* lock dpll */
|
||
|
clrsetbits_le32(priv->clkmode_reg, CM_CLKMODE_DPLL_DPLL_EN_MASK,
|
||
|
DPLL_EN_LOCK << CM_CLKMODE_DPLL_EN_SHIFT);
|
||
|
|
||
|
/* wait till the dpll locks */
|
||
|
if (!wait_on_value(ST_DPLL_CLK_MASK, ST_DPLL_CLK_MASK,
|
||
|
(void *)priv->idlest_reg, LDELAY)) {
|
||
|
dev_err(clk->dev, "failed locking dpll\n");
|
||
|
hang();
|
||
|
}
|
||
|
|
||
|
return round_rate;
|
||
|
}
|
||
|
|
||
|
static ulong clk_ti_am3_dpll_get_rate(struct clk *clk)
|
||
|
{
|
||
|
struct clk_ti_am3_dpll_priv *priv = dev_get_priv(clk->dev);
|
||
|
u64 rate;
|
||
|
u32 m, n, v;
|
||
|
|
||
|
/* Return bypass rate if DPLL is bypassed */
|
||
|
v = readl(priv->clkmode_reg);
|
||
|
v &= CM_CLKMODE_DPLL_EN_MASK;
|
||
|
v >>= CM_CLKMODE_DPLL_EN_SHIFT;
|
||
|
|
||
|
switch (v) {
|
||
|
case DPLL_EN_MN_BYPASS:
|
||
|
case DPLL_EN_LOW_POWER_BYPASS:
|
||
|
case DPLL_EN_FAST_RELOCK_BYPASS:
|
||
|
rate = clk_get_rate(&priv->clk_bypass);
|
||
|
dev_dbg(clk->dev, "rate=%lld\n", rate);
|
||
|
return rate;
|
||
|
}
|
||
|
|
||
|
v = readl(priv->clksel_reg);
|
||
|
m = v & CM_CLKSEL_DPLL_M_MASK;
|
||
|
m >>= CM_CLKSEL_DPLL_M_SHIFT;
|
||
|
n = v & CM_CLKSEL_DPLL_N_MASK;
|
||
|
n >>= CM_CLKSEL_DPLL_N_SHIFT;
|
||
|
|
||
|
rate = clk_get_rate(&priv->clk_ref) * m;
|
||
|
do_div(rate, n + 1);
|
||
|
dev_dbg(clk->dev, "rate=%lld\n", rate);
|
||
|
return rate;
|
||
|
}
|
||
|
|
||
|
const struct clk_ops clk_ti_am3_dpll_ops = {
|
||
|
.round_rate = clk_ti_am3_dpll_round_rate,
|
||
|
.get_rate = clk_ti_am3_dpll_get_rate,
|
||
|
.set_rate = clk_ti_am3_dpll_set_rate,
|
||
|
};
|
||
|
|
||
|
static int clk_ti_am3_dpll_remove(struct udevice *dev)
|
||
|
{
|
||
|
struct clk_ti_am3_dpll_priv *priv = dev_get_priv(dev);
|
||
|
int err;
|
||
|
|
||
|
err = clk_release_all(&priv->clk_bypass, 1);
|
||
|
if (err) {
|
||
|
dev_err(dev, "failed to release bypass clock\n");
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
err = clk_release_all(&priv->clk_ref, 1);
|
||
|
if (err) {
|
||
|
dev_err(dev, "failed to release reference clock\n");
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int clk_ti_am3_dpll_probe(struct udevice *dev)
|
||
|
{
|
||
|
struct clk_ti_am3_dpll_priv *priv = dev_get_priv(dev);
|
||
|
int err;
|
||
|
|
||
|
err = clk_get_by_index(dev, 0, &priv->clk_ref);
|
||
|
if (err) {
|
||
|
dev_err(dev, "failed to get reference clock\n");
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
err = clk_get_by_index(dev, 1, &priv->clk_bypass);
|
||
|
if (err) {
|
||
|
dev_err(dev, "failed to get bypass clock\n");
|
||
|
return err;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int clk_ti_am3_dpll_of_to_plat(struct udevice *dev)
|
||
|
{
|
||
|
struct clk_ti_am3_dpll_priv *priv = dev_get_priv(dev);
|
||
|
struct clk_ti_am3_dpll_drv_data *data =
|
||
|
(struct clk_ti_am3_dpll_drv_data *)dev_get_driver_data(dev);
|
||
|
|
||
|
priv->max_rate = data->max_rate;
|
||
|
|
||
|
priv->clkmode_reg = dev_read_addr_index(dev, 0);
|
||
|
if (priv->clkmode_reg == FDT_ADDR_T_NONE) {
|
||
|
dev_err(dev, "failed to get clkmode register\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
dev_dbg(dev, "clkmode_reg=0x%08lx\n", priv->clkmode_reg);
|
||
|
|
||
|
priv->idlest_reg = dev_read_addr_index(dev, 1);
|
||
|
if (priv->idlest_reg == FDT_ADDR_T_NONE) {
|
||
|
dev_err(dev, "failed to get idlest register\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
dev_dbg(dev, "idlest_reg=0x%08lx\n", priv->idlest_reg);
|
||
|
|
||
|
priv->clksel_reg = dev_read_addr_index(dev, 2);
|
||
|
if (priv->clksel_reg == FDT_ADDR_T_NONE) {
|
||
|
dev_err(dev, "failed to get clksel register\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
dev_dbg(dev, "clksel_reg=0x%08lx\n", priv->clksel_reg);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static const struct clk_ti_am3_dpll_drv_data dpll_no_gate_data = {
|
||
|
.max_rate = 1000000000
|
||
|
};
|
||
|
|
||
|
static const struct clk_ti_am3_dpll_drv_data dpll_no_gate_j_type_data = {
|
||
|
.max_rate = 2000000000
|
||
|
};
|
||
|
|
||
|
static const struct clk_ti_am3_dpll_drv_data dpll_core_data = {
|
||
|
.max_rate = 1000000000
|
||
|
};
|
||
|
|
||
|
static const struct udevice_id clk_ti_am3_dpll_of_match[] = {
|
||
|
{.compatible = "ti,am3-dpll-core-clock",
|
||
|
.data = (ulong)&dpll_core_data},
|
||
|
{.compatible = "ti,am3-dpll-no-gate-clock",
|
||
|
.data = (ulong)&dpll_no_gate_data},
|
||
|
{.compatible = "ti,am3-dpll-no-gate-j-type-clock",
|
||
|
.data = (ulong)&dpll_no_gate_j_type_data},
|
||
|
{}
|
||
|
};
|
||
|
|
||
|
U_BOOT_DRIVER(clk_ti_am3_dpll) = {
|
||
|
.name = "ti_am3_dpll_clock",
|
||
|
.id = UCLASS_CLK,
|
||
|
.of_match = clk_ti_am3_dpll_of_match,
|
||
|
.ofdata_to_platdata = clk_ti_am3_dpll_of_to_plat,
|
||
|
.probe = clk_ti_am3_dpll_probe,
|
||
|
.remove = clk_ti_am3_dpll_remove,
|
||
|
.priv_auto = sizeof(struct clk_ti_am3_dpll_priv),
|
||
|
.ops = &clk_ti_am3_dpll_ops,
|
||
|
};
|