clk.c
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#include <linux/clk.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include "clk.h"
DEFINE_SPINLOCK(imx_ccm_lock);
void __init imx_check_clocks(struct clk *clks[], unsigned int count)
{
unsigned i;
for (i = 0; i < count; i++)
if (IS_ERR(clks[i]))
pr_err("i.MX clk %u: register failed with %ld\n",
i, PTR_ERR(clks[i]));
}
static struct clk * __init imx_obtain_fixed_clock_from_dt(const char *name)
{
struct of_phandle_args phandle;
struct clk *clk = ERR_PTR(-ENODEV);
char *path;
path = kasprintf(GFP_KERNEL, "/clocks/%s", name);
if (!path)
return ERR_PTR(-ENOMEM);
phandle.np = of_find_node_by_path(path);
kfree(path);
if (phandle.np) {
clk = of_clk_get_from_provider(&phandle);
of_node_put(phandle.np);
}
return clk;
}
struct clk * __init imx_obtain_fixed_clock(
const char *name, unsigned long rate)
{
struct clk *clk;
clk = imx_obtain_fixed_clock_from_dt(name);
if (IS_ERR(clk))
clk = imx_clk_fixed(name, rate);
return clk;
}
/*
* This fixups the register CCM_CSCMR1 write value.
* The write/read/divider values of the aclk_podf field
* of that register have the relationship described by
* the following table:
*
* write value read value divider
* 3b'000 3b'110 7
* 3b'001 3b'111 8
* 3b'010 3b'100 5
* 3b'011 3b'101 6
* 3b'100 3b'010 3
* 3b'101 3b'011 4
* 3b'110 3b'000 1
* 3b'111 3b'001 2(default)
*
* That's why we do the xor operation below.
*/
#define CSCMR1_FIXUP 0x00600000
void imx_cscmr1_fixup(u32 *val)
{
*val ^= CSCMR1_FIXUP;
return;
}
static int imx_keep_uart_clocks __initdata;
static struct clk ** const *imx_uart_clocks __initdata;
static int __init imx_keep_uart_clocks_param(char *str)
{
imx_keep_uart_clocks = 1;
return 0;
}
__setup_param("earlycon", imx_keep_uart_earlycon,
imx_keep_uart_clocks_param, 0);
__setup_param("earlyprintk", imx_keep_uart_earlyprintk,
imx_keep_uart_clocks_param, 0);
void __init imx_register_uart_clocks(struct clk ** const clks[])
{
if (imx_keep_uart_clocks) {
int i;
imx_uart_clocks = clks;
for (i = 0; imx_uart_clocks[i]; i++)
clk_prepare_enable(*imx_uart_clocks[i]);
}
}
static int __init imx_clk_disable_uart(void)
{
if (imx_keep_uart_clocks && imx_uart_clocks) {
int i;
for (i = 0; imx_uart_clocks[i]; i++)
clk_disable_unprepare(*imx_uart_clocks[i]);
}
return 0;
}
late_initcall_sync(imx_clk_disable_uart);