WSL2-Linux-Kernel/arch/arm/mach-imx/clk.c

66 строки
1.5 KiB
C

#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);
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;
}