u-boot/drivers/clk/at91/sckc.c

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// SPDX-License-Identifier: GPL-2.0+
/*
* Slow clock support for AT91 architectures.
*
* Copyright (C) 2020 Microchip Technology Inc. and its subsidiaries
*
* Author: Claudiu Beznea <claudiu.beznea@microchip.com>
*/
#include <common.h>
#include <clk-uclass.h>
#include <dm.h>
#include <dt-bindings/clk/at91.h>
#include <linux/clk-provider.h>
#include "pmc.h"
#define UBOOT_DM_CLK_AT91_SAM9X60_TD_SLCK "at91-sam9x60-td-slck"
#define UBOOT_DM_CLK_AT91_SCKC "at91-sckc"
#define AT91_OSC_SEL BIT(24)
#define AT91_OSC_SEL_SHIFT (24)
struct sam9x60_sckc {
void __iomem *reg;
const char **parent_names;
unsigned int num_parents;
struct clk clk;
};
#define to_sam9x60_sckc(c) container_of(c, struct sam9x60_sckc, clk)
static int sam9x60_sckc_of_xlate(struct clk *clk,
struct ofnode_phandle_args *args)
{
if (args->args_count != 1) {
debug("AT91: SCKC: Invalid args_count: %d\n", args->args_count);
return -EINVAL;
}
clk->id = AT91_TO_CLK_ID(PMC_TYPE_SLOW, args->args[0]);
return 0;
}
static const struct clk_ops sam9x60_sckc_ops = {
.of_xlate = sam9x60_sckc_of_xlate,
.get_rate = clk_generic_get_rate,
};
static int sam9x60_td_slck_set_parent(struct clk *clk, struct clk *parent)
{
struct sam9x60_sckc *sckc = to_sam9x60_sckc(clk);
u32 i;
for (i = 0; i < sckc->num_parents; i++) {
if (!strcmp(parent->dev->name, sckc->parent_names[i]))
break;
}
if (i == sckc->num_parents)
return -EINVAL;
pmc_update_bits(sckc->reg, 0, AT91_OSC_SEL, (i << AT91_OSC_SEL_SHIFT));
return 0;
}
static const struct clk_ops sam9x60_td_slck_ops = {
.get_rate = clk_generic_get_rate,
.set_parent = sam9x60_td_slck_set_parent,
};
static struct clk *at91_sam9x60_clk_register_td_slck(struct sam9x60_sckc *sckc,
const char *name, const char * const *parent_names,
int num_parents)
{
struct clk *clk;
int ret = -ENOMEM;
u32 val, i;
if (!sckc || !name || !parent_names || num_parents != 2)
return ERR_PTR(-EINVAL);
sckc->parent_names = kzalloc(sizeof(*sckc->parent_names) * num_parents,
GFP_KERNEL);
if (!sckc->parent_names)
return ERR_PTR(ret);
for (i = 0; i < num_parents; i++) {
sckc->parent_names[i] = kmemdup(parent_names[i],
strlen(parent_names[i]) + 1, GFP_KERNEL);
if (!sckc->parent_names[i])
goto free;
}
sckc->num_parents = num_parents;
pmc_read(sckc->reg, 0, &val);
val = (val & AT91_OSC_SEL) >> AT91_OSC_SEL_SHIFT;
clk = &sckc->clk;
ret = clk_register(clk, UBOOT_DM_CLK_AT91_SAM9X60_TD_SLCK, name,
parent_names[val]);
if (ret)
goto free;
return clk;
free:
for (; i >= 0; i--)
kfree(sckc->parent_names[i]);
kfree(sckc->parent_names);
return ERR_PTR(ret);
}
U_BOOT_DRIVER(at91_sam9x60_td_slck) = {
.name = UBOOT_DM_CLK_AT91_SAM9X60_TD_SLCK,
.id = UCLASS_CLK,
.ops = &sam9x60_td_slck_ops,
.flags = DM_FLAG_PRE_RELOC,
};
static int at91_sam9x60_sckc_probe(struct udevice *dev)
{
struct sam9x60_sckc *sckc = dev_get_priv(dev);
void __iomem *base = (void *)devfdt_get_addr(dev);
const char *slow_rc_osc, *slow_osc;
const char *parents[2];
struct clk *clk, c;
int ret;
ret = clk_get_by_index(dev, 0, &c);
if (ret)
return ret;
slow_rc_osc = clk_hw_get_name(&c);
ret = clk_get_by_index(dev, 1, &c);
if (ret)
return ret;
slow_osc = clk_hw_get_name(&c);
clk = clk_register_fixed_factor(NULL, "md_slck", slow_rc_osc, 0, 1, 1);
if (IS_ERR(clk))
return PTR_ERR(clk);
clk_dm(AT91_TO_CLK_ID(PMC_TYPE_SLOW, 0), clk);
parents[0] = slow_rc_osc;
parents[1] = slow_osc;
sckc[1].reg = base;
clk = at91_sam9x60_clk_register_td_slck(&sckc[1], "td_slck",
parents, 2);
if (IS_ERR(clk))
return PTR_ERR(clk);
clk_dm(AT91_TO_CLK_ID(PMC_TYPE_SLOW, 1), clk);
return 0;
}
static const struct udevice_id sam9x60_sckc_ids[] = {
{ .compatible = "microchip,sam9x60-sckc" },
{ /* Sentinel. */ },
};
U_BOOT_DRIVER(at91_sckc) = {
.name = UBOOT_DM_CLK_AT91_SCKC,
.id = UCLASS_CLK,
.of_match = sam9x60_sckc_ids,
.priv_auto = sizeof(struct sam9x60_sckc) * 2,
.ops = &sam9x60_sckc_ops,
.probe = at91_sam9x60_sckc_probe,
.flags = DM_FLAG_PRE_RELOC,
};