u-boot/drivers/clk/clk-xlnx-clock-wizard.c
Zhengxun 2b157d8127 clk: zynq: Add clock wizard driver
The Clocking Wizard IP supports clock circuits customized
to your clocking requirements. The wizard support for
dynamically reconfiguring the clocking primitives for
Multiply, Divide, Phase Shift/Offset, or Duty Cycle.

Limited by U-Boot clk uclass without set_phase API, this
patch only provides set_rate to modify the frequency.

Signed-off-by: Zhengxun <zhengxunli.mxic@gmail.com>
Reviewed-by: Sean Anderson <sean.anderson@seco.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
2021-06-23 09:48:35 +02:00

186 lines
4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Xilinx 'Clocking Wizard' driver
*
* Copyright (c) 2021 Macronix Inc.
*
* Author: Zhengxun Li <zhengxunli@mxic.com.tw>
*/
#include <common.h>
#include <clk-uclass.h>
#include <dm.h>
#include <div64.h>
#include <dm/device_compat.h>
#include <linux/iopoll.h>
#include <linux/bitfield.h>
#define SRR 0x0
#define SR 0x4
#define SR_LOCKED BIT(0)
#define CCR(x) (0x200 + ((x) * 4))
#define FBOUT_CFG CCR(0)
#define FBOUT_DIV(x) (x)
#define FBOUT_DIV_MASK GENMASK(7, 0)
#define FBOUT_GET_DIV(x) FIELD_GET(FBOUT_DIV_MASK, x)
#define FBOUT_MUL(x) ((x) << 8)
#define FBOUT_MUL_MASK GENMASK(15, 8)
#define FBOUT_GET_MUL(x) FIELD_GET(FBOUT_MUL_MASK, x)
#define FBOUT_FRAC(x) ((x) << 16)
#define FBOUT_FRAC_MASK GENMASK(25, 16)
#define FBOUT_GET_FRAC(x) FIELD_GET(FBOUT_FRAC_MASK, x)
#define FBOUT_FRAC_EN BIT(26)
#define FBOUT_PHASE CCR(1)
#define OUT_CFG(x) CCR(2 + ((x) * 3))
#define OUT_DIV(x) (x)
#define OUT_DIV_MASK GENMASK(7, 0)
#define OUT_GET_DIV(x) FIELD_GET(OUT_DIV_MASK, x)
#define OUT_FRAC(x) ((x) << 8)
#define OUT_GET_MASK GENMASK(17, 8)
#define OUT_GET_FRAC(x) FIELD_GET(OUT_GET_MASK, x)
#define OUT_FRAC_EN BIT(18)
#define OUT_PHASE(x) CCR(3 + ((x) * 3))
#define OUT_DUTY(x) CCR(4 + ((x) * 3))
#define CTRL CCR(23)
#define CTRL_SEN BIT(2)
#define CTRL_SADDR BIT(1)
#define CTRL_LOAD BIT(0)
/**
* struct clkwzrd - Clock wizard private data structure
*
* @base: memory base
* @vco_clk: voltage-controlled oscillator frequency
*
*/
struct clkwzd {
void *base;
u64 vco_clk;
};
struct clkwzd_plat {
fdt_addr_t addr;
};
static int clk_wzrd_enable(struct clk *clk)
{
struct clkwzd *priv = dev_get_priv(clk->dev);
int ret;
u32 val;
ret = readl_poll_sleep_timeout(priv->base + SR, val, val & SR_LOCKED,
1, 100);
if (!ret) {
writel(CTRL_SEN | CTRL_SADDR | CTRL_LOAD, priv->base + CTRL);
writel(CTRL_SADDR, priv->base + CTRL);
ret = readl_poll_sleep_timeout(priv->base + SR, val,
val & SR_LOCKED, 1, 100);
}
return ret;
}
static unsigned long clk_wzrd_set_rate(struct clk *clk, ulong rate)
{
struct clkwzd *priv = dev_get_priv(clk->dev);
u64 div;
u32 cfg;
/* Get output clock divide value */
div = DIV_ROUND_DOWN_ULL(priv->vco_clk * 1000, rate);
if (div < 1000 || div > 255999)
return -EINVAL;
cfg = OUT_DIV((u32)div / 1000);
writel(cfg, priv->base + OUT_CFG(clk->id));
return 0;
}
static struct clk_ops clk_wzrd_ops = {
.enable = clk_wzrd_enable,
.set_rate = clk_wzrd_set_rate,
};
static int clk_wzrd_probe(struct udevice *dev)
{
struct clkwzd_plat *plat = dev_get_plat(dev);
struct clkwzd *priv = dev_get_priv(dev);
struct clk clk_in1;
u64 clock, vco_clk;
u32 cfg;
int ret;
priv->base = (void *)plat->addr;
ret = clk_get_by_name(dev, "clk_in1", &clk_in1);
if (ret < 0) {
dev_err(dev, "failed to get clock\n");
return ret;
}
clock = clk_get_rate(&clk_in1);
if (IS_ERR_VALUE(clock)) {
dev_err(dev, "failed to get rate\n");
return clock;
}
ret = clk_enable(&clk_in1);
if (ret) {
dev_err(dev, "failed to enable clock\n");
clk_free(&clk_in1);
return ret;
}
/* Read clock configuration registers */
cfg = readl(priv->base + FBOUT_CFG);
/* Recalculate VCO rate */
if (cfg & FBOUT_FRAC_EN)
vco_clk = DIV_ROUND_DOWN_ULL(clock *
((FBOUT_GET_MUL(cfg) * 1000) +
FBOUT_GET_FRAC(cfg)),
1000);
else
vco_clk = clock * FBOUT_GET_MUL(cfg);
priv->vco_clk = DIV_ROUND_DOWN_ULL(vco_clk, FBOUT_GET_DIV(cfg));
return 0;
}
static int clk_wzrd_of_to_plat(struct udevice *dev)
{
struct clkwzd_plat *plat = dev_get_plat(dev);
plat->addr = dev_read_addr(dev);
if (plat->addr == FDT_ADDR_T_NONE)
return -EINVAL;
return 0;
}
static const struct udevice_id clk_wzrd_ids[] = {
{ .compatible = "xlnx,clocking-wizard" },
{ /* sentinel */ }
};
U_BOOT_DRIVER(clk_wzrd) = {
.name = "zynq-clk-wizard",
.id = UCLASS_CLK,
.of_match = clk_wzrd_ids,
.ops = &clk_wzrd_ops,
.probe = clk_wzrd_probe,
.of_to_plat = clk_wzrd_of_to_plat,
.priv_auto = sizeof(struct clkwzd),
.plat_auto = sizeof(struct clkwzd_plat),
};