linux/drivers/clk/imx/clk-pfd.c
Arnd Bergmann 64ea30d1a1 clk: imx: fix compile testing imxrt1050
Randconfig testing revealed multiple issues with this driver:

ERROR: modpost: missing MODULE_LICENSE() in drivers/clk/imx/clk-imxrt1050.o
ERROR: modpost: "imx_clk_hw_pllv3" [drivers/clk/imx/clk-imxrt1050.ko] undefined!
ERROR: modpost: "imx_clk_hw_pfd" [drivers/clk/imx/clk-imxrt1050.ko] undefined!

Export the necessary symbols from the core clk driver and add the
license and author tags. To find this type of problem more easily
in the future, also enable building on other platforms, as we do for
the other i.MX clk drivers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20221215165836.2136448-1-arnd@kernel.org
Acked-by: Jesse Taube <Mr.Bossman075@gmail.com>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
2023-02-10 15:25:33 -08:00

158 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2012 Freescale Semiconductor, Inc.
* Copyright 2012 Linaro Ltd.
*/
#include <linux/clk-provider.h>
#include <linux/export.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/err.h>
#include "clk.h"
/**
* struct clk_pfd - IMX PFD clock
* @hw: clock source
* @reg: PFD register address
* @idx: the index of PFD encoded in the register
*
* PFD clock found on i.MX6 series. Each register for PFD has 4 clk_pfd
* data encoded, and member idx is used to specify the one. And each
* register has SET, CLR and TOG registers at offset 0x4 0x8 and 0xc.
*/
struct clk_pfd {
struct clk_hw hw;
void __iomem *reg;
u8 idx;
};
#define to_clk_pfd(_hw) container_of(_hw, struct clk_pfd, hw)
#define SET 0x4
#define CLR 0x8
#define OTG 0xc
static int clk_pfd_enable(struct clk_hw *hw)
{
struct clk_pfd *pfd = to_clk_pfd(hw);
writel_relaxed(1 << ((pfd->idx + 1) * 8 - 1), pfd->reg + CLR);
return 0;
}
static void clk_pfd_disable(struct clk_hw *hw)
{
struct clk_pfd *pfd = to_clk_pfd(hw);
writel_relaxed(1 << ((pfd->idx + 1) * 8 - 1), pfd->reg + SET);
}
static unsigned long clk_pfd_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_pfd *pfd = to_clk_pfd(hw);
u64 tmp = parent_rate;
u8 frac = (readl_relaxed(pfd->reg) >> (pfd->idx * 8)) & 0x3f;
tmp *= 18;
do_div(tmp, frac);
return tmp;
}
static long clk_pfd_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *prate)
{
u64 tmp = *prate;
u8 frac;
tmp = tmp * 18 + rate / 2;
do_div(tmp, rate);
frac = tmp;
if (frac < 12)
frac = 12;
else if (frac > 35)
frac = 35;
tmp = *prate;
tmp *= 18;
do_div(tmp, frac);
return tmp;
}
static int clk_pfd_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_pfd *pfd = to_clk_pfd(hw);
u64 tmp = parent_rate;
u8 frac;
tmp = tmp * 18 + rate / 2;
do_div(tmp, rate);
frac = tmp;
if (frac < 12)
frac = 12;
else if (frac > 35)
frac = 35;
writel_relaxed(0x3f << (pfd->idx * 8), pfd->reg + CLR);
writel_relaxed(frac << (pfd->idx * 8), pfd->reg + SET);
return 0;
}
static int clk_pfd_is_enabled(struct clk_hw *hw)
{
struct clk_pfd *pfd = to_clk_pfd(hw);
if (readl_relaxed(pfd->reg) & (1 << ((pfd->idx + 1) * 8 - 1)))
return 0;
return 1;
}
static const struct clk_ops clk_pfd_ops = {
.enable = clk_pfd_enable,
.disable = clk_pfd_disable,
.recalc_rate = clk_pfd_recalc_rate,
.round_rate = clk_pfd_round_rate,
.set_rate = clk_pfd_set_rate,
.is_enabled = clk_pfd_is_enabled,
};
struct clk_hw *imx_clk_hw_pfd(const char *name, const char *parent_name,
void __iomem *reg, u8 idx)
{
struct clk_pfd *pfd;
struct clk_hw *hw;
struct clk_init_data init;
int ret;
pfd = kzalloc(sizeof(*pfd), GFP_KERNEL);
if (!pfd)
return ERR_PTR(-ENOMEM);
pfd->reg = reg;
pfd->idx = idx;
init.name = name;
init.ops = &clk_pfd_ops;
init.flags = 0;
init.parent_names = &parent_name;
init.num_parents = 1;
pfd->hw.init = &init;
hw = &pfd->hw;
ret = clk_hw_register(NULL, hw);
if (ret) {
kfree(pfd);
return ERR_PTR(ret);
}
return hw;
}
EXPORT_SYMBOL_GPL(imx_clk_hw_pfd);