linux/drivers/clk/rockchip/clk-ddr.c
Shawn Lin 4a262b14c5 clk: rockchip: don't return NULL when failing to register ddrclk branch
rockchip_clk_register_ddrclk should not return NULL when failing
to call clk_register, otherwise rockchip_clk_register_branches
prints "unknown clock type". The actual case is that it's a known
clock type but we fail to register it, which may makes user confuse
the reason of failure. And the pr_err here is pointless as
rockchip_clk_register_branches will also print the similar message.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-10-16 02:39:58 +02:00

152 lines
3.8 KiB
C

/*
* Copyright (c) 2016 Rockchip Electronics Co. Ltd.
* Author: Lin Huang <hl@rock-chips.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/arm-smccc.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <soc/rockchip/rockchip_sip.h>
#include "clk.h"
struct rockchip_ddrclk {
struct clk_hw hw;
void __iomem *reg_base;
int mux_offset;
int mux_shift;
int mux_width;
int div_shift;
int div_width;
int ddr_flag;
spinlock_t *lock;
};
#define to_rockchip_ddrclk_hw(hw) container_of(hw, struct rockchip_ddrclk, hw)
static int rockchip_ddrclk_sip_set_rate(struct clk_hw *hw, unsigned long drate,
unsigned long prate)
{
struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
unsigned long flags;
struct arm_smccc_res res;
spin_lock_irqsave(ddrclk->lock, flags);
arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, drate, 0,
ROCKCHIP_SIP_CONFIG_DRAM_SET_RATE,
0, 0, 0, 0, &res);
spin_unlock_irqrestore(ddrclk->lock, flags);
return res.a0;
}
static unsigned long
rockchip_ddrclk_sip_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct arm_smccc_res res;
arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
ROCKCHIP_SIP_CONFIG_DRAM_GET_RATE,
0, 0, 0, 0, &res);
return res.a0;
}
static long rockchip_ddrclk_sip_round_rate(struct clk_hw *hw,
unsigned long rate,
unsigned long *prate)
{
struct arm_smccc_res res;
arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, rate, 0,
ROCKCHIP_SIP_CONFIG_DRAM_ROUND_RATE,
0, 0, 0, 0, &res);
return res.a0;
}
static u8 rockchip_ddrclk_get_parent(struct clk_hw *hw)
{
struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
int num_parents = clk_hw_get_num_parents(hw);
u32 val;
val = clk_readl(ddrclk->reg_base +
ddrclk->mux_offset) >> ddrclk->mux_shift;
val &= GENMASK(ddrclk->mux_width - 1, 0);
if (val >= num_parents)
return -EINVAL;
return val;
}
static const struct clk_ops rockchip_ddrclk_sip_ops = {
.recalc_rate = rockchip_ddrclk_sip_recalc_rate,
.set_rate = rockchip_ddrclk_sip_set_rate,
.round_rate = rockchip_ddrclk_sip_round_rate,
.get_parent = rockchip_ddrclk_get_parent,
};
struct clk *rockchip_clk_register_ddrclk(const char *name, int flags,
const char *const *parent_names,
u8 num_parents, int mux_offset,
int mux_shift, int mux_width,
int div_shift, int div_width,
int ddr_flag, void __iomem *reg_base,
spinlock_t *lock)
{
struct rockchip_ddrclk *ddrclk;
struct clk_init_data init;
struct clk *clk;
ddrclk = kzalloc(sizeof(*ddrclk), GFP_KERNEL);
if (!ddrclk)
return ERR_PTR(-ENOMEM);
init.name = name;
init.parent_names = parent_names;
init.num_parents = num_parents;
init.flags = flags;
init.flags |= CLK_SET_RATE_NO_REPARENT;
switch (ddr_flag) {
case ROCKCHIP_DDRCLK_SIP:
init.ops = &rockchip_ddrclk_sip_ops;
break;
default:
pr_err("%s: unsupported ddrclk type %d\n", __func__, ddr_flag);
kfree(ddrclk);
return ERR_PTR(-EINVAL);
}
ddrclk->reg_base = reg_base;
ddrclk->lock = lock;
ddrclk->hw.init = &init;
ddrclk->mux_offset = mux_offset;
ddrclk->mux_shift = mux_shift;
ddrclk->mux_width = mux_width;
ddrclk->div_shift = div_shift;
ddrclk->div_width = div_width;
ddrclk->ddr_flag = ddr_flag;
clk = clk_register(NULL, &ddrclk->hw);
if (IS_ERR(clk))
kfree(ddrclk);
return clk;
}