/*
|
* Copyright (C) 2016 Atmel Corporation
|
* Wenyou.Yang <wenyou.yang@atmel.com>
|
*
|
* SPDX-License-Identifier: GPL-2.0+
|
*/
|
|
#include <common.h>
|
#include <clk-uclass.h>
|
#include <dm.h>
|
#include <linux/io.h>
|
#include <mach/at91_pmc.h>
|
#include "pmc.h"
|
|
#define SYSTEM_MAX_ID 31
|
|
/**
|
* at91_system_clk_bind() - for the system clock driver
|
* Recursively bind its children as clk devices.
|
*
|
* @return: 0 on success, or negative error code on failure
|
*/
|
static int at91_system_clk_bind(struct udevice *dev)
|
{
|
return at91_clk_sub_device_bind(dev, "system-clk");
|
}
|
|
static const struct udevice_id at91_system_clk_match[] = {
|
{ .compatible = "atmel,at91rm9200-clk-system" },
|
{}
|
};
|
|
U_BOOT_DRIVER(at91_system_clk) = {
|
.name = "at91-system-clk",
|
.id = UCLASS_MISC,
|
.of_match = at91_system_clk_match,
|
.bind = at91_system_clk_bind,
|
};
|
|
/*----------------------------------------------------------*/
|
|
static inline int is_pck(int id)
|
{
|
return (id >= 8) && (id <= 15);
|
}
|
|
static int system_clk_enable(struct clk *clk)
|
{
|
struct pmc_platdata *plat = dev_get_platdata(clk->dev);
|
struct at91_pmc *pmc = plat->reg_base;
|
u32 mask;
|
|
if (clk->id > SYSTEM_MAX_ID)
|
return -EINVAL;
|
|
mask = BIT(clk->id);
|
|
writel(mask, &pmc->scer);
|
|
/**
|
* For the programmable clocks the Ready status in the PMC
|
* status register should be checked after enabling.
|
* For other clocks this is unnecessary.
|
*/
|
if (!is_pck(clk->id))
|
return 0;
|
|
while (!(readl(&pmc->sr) & mask))
|
;
|
|
return 0;
|
}
|
|
static struct clk_ops system_clk_ops = {
|
.of_xlate = at91_clk_of_xlate,
|
.enable = system_clk_enable,
|
};
|
|
U_BOOT_DRIVER(system_clk) = {
|
.name = "system-clk",
|
.id = UCLASS_CLK,
|
.probe = at91_clk_probe,
|
.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
|
.ops = &system_clk_ops,
|
};
|
