u-boot/drivers/clk/mtmips/clk-mt7620.c
Weijie Gao d9a5da72d7 clk: add clock driver for MediaTek MT7620 SoC
This patch adds a clock driver for MediaTek MT7620 SoC.
This driver provides clock gate control as well as getting clock frequency
for CPU/SYS/XTAL and some peripherals.

Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
2021-01-24 21:39:26 +01:00

159 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020 MediaTek Inc. All Rights Reserved.
*
* Author: Weijie Gao <weijie.gao@mediatek.com>
*/
#include <clk-uclass.h>
#include <dm.h>
#include <dm/device_compat.h>
#include <dt-bindings/clock/mt7620-clk.h>
#include <misc.h>
#include <mach/mt7620-sysc.h>
/* CLKCFG1 */
#define CLKCFG1_REG 0x30
#define CLK_SRC_CPU -1
#define CLK_SRC_CPU_D2 -2
#define CLK_SRC_SYS -3
#define CLK_SRC_XTAL -4
#define CLK_SRC_PERI -5
struct mt7620_clk_priv {
struct udevice *dev;
struct udevice *sysc;
struct mt7620_sysc_clks clks;
};
static const int mt7620_clks[] = {
[CLK_SYS] = CLK_SRC_SYS,
[CLK_CPU] = CLK_SRC_CPU,
[CLK_XTAL] = CLK_SRC_XTAL,
[CLK_MIPS_CNT] = CLK_SRC_CPU_D2,
[CLK_UARTF] = CLK_SRC_PERI,
[CLK_UARTL] = CLK_SRC_PERI,
[CLK_SPI] = CLK_SRC_SYS,
[CLK_I2C] = CLK_SRC_PERI,
[CLK_I2S] = CLK_SRC_PERI,
};
static ulong mt7620_clk_get_rate(struct clk *clk)
{
struct mt7620_clk_priv *priv = dev_get_priv(clk->dev);
if (clk->id >= ARRAY_SIZE(mt7620_clks))
return 0;
switch (mt7620_clks[clk->id]) {
case CLK_SRC_CPU:
return priv->clks.cpu_clk;
case CLK_SRC_CPU_D2:
return priv->clks.cpu_clk / 2;
case CLK_SRC_SYS:
return priv->clks.sys_clk;
case CLK_SRC_XTAL:
return priv->clks.xtal_clk;
case CLK_SRC_PERI:
return priv->clks.peri_clk;
default:
return mt7620_clks[clk->id];
}
}
static int mt7620_clkcfg1_rmw(struct mt7620_clk_priv *priv, u32 clr, u32 set)
{
u32 val;
int ret;
ret = misc_read(priv->sysc, CLKCFG1_REG, &val, sizeof(val));
if (ret) {
dev_err(priv->dev, "mt7620_clk: failed to read CLKCFG1\n");
return ret;
}
val &= ~clr;
val |= set;
ret = misc_write(priv->sysc, CLKCFG1_REG, &val, sizeof(val));
if (ret) {
dev_err(priv->dev, "mt7620_clk: failed to write CLKCFG1\n");
return ret;
}
return 0;
}
static int mt7620_clk_enable(struct clk *clk)
{
struct mt7620_clk_priv *priv = dev_get_priv(clk->dev);
if (clk->id > 30)
return -1;
return mt7620_clkcfg1_rmw(priv, 0, BIT(clk->id));
}
static int mt7620_clk_disable(struct clk *clk)
{
struct mt7620_clk_priv *priv = dev_get_priv(clk->dev);
if (clk->id > 30)
return -1;
return mt7620_clkcfg1_rmw(priv, BIT(clk->id), 0);
}
const struct clk_ops mt7620_clk_ops = {
.enable = mt7620_clk_enable,
.disable = mt7620_clk_disable,
.get_rate = mt7620_clk_get_rate,
};
static int mt7620_clk_probe(struct udevice *dev)
{
struct mt7620_clk_priv *priv = dev_get_priv(dev);
struct ofnode_phandle_args sysc_args;
int ret;
ret = ofnode_parse_phandle_with_args(dev_ofnode(dev), "mediatek,sysc", NULL,
0, 0, &sysc_args);
if (ret) {
dev_err(dev, "mt7620_clk: sysc property not found\n");
return ret;
}
ret = uclass_get_device_by_ofnode(UCLASS_MISC, sysc_args.node,
&priv->sysc);
if (ret) {
dev_err(dev, "mt7620_clk: failed to sysc device\n");
return ret;
}
ret = misc_ioctl(priv->sysc, MT7620_SYSC_IOCTL_GET_CLK,
&priv->clks);
if (ret) {
dev_err(dev, "mt7620_clk: failed to get base clocks\n");
return ret;
}
priv->dev = dev;
return 0;
}
static const struct udevice_id mt7620_clk_ids[] = {
{ .compatible = "mediatek,mt7620-clk" },
{ }
};
U_BOOT_DRIVER(mt7620_clk) = {
.name = "mt7620-clk",
.id = UCLASS_CLK,
.of_match = mt7620_clk_ids,
.probe = mt7620_clk_probe,
.priv_auto = sizeof(struct mt7620_clk_priv),
.ops = &mt7620_clk_ops,
.flags = DM_FLAG_PRE_RELOC,
};