Commit 97fa4cf4 authored by Sebastian Hesselbarth's avatar Sebastian Hesselbarth Committed by Thomas Petazzoni

clk: mvebu: add mvebu core clocks.

This driver allows to provide DT clocks for core clocks found on
Marvell Kirkwood, Dove & 370/XP SoCs. The core clock frequencies and
ratios are determined by decoding the Sample-At-Reset registers.

Although technically correct, using a divider of 0 will lead to
div_by_zero panic. Let's use a ratio of 0/1 instead to fail later
with a zero clock.
Signed-off-by: default avatarGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: default avatarSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: default avatarAndrew Lunn <andrew@lunn.ch>
Tested-by Gregory CLEMENT <gregory.clement@free-electrons.com>
parent f4a75d2e
* Core Clock bindings for Marvell MVEBU SoCs
Marvell MVEBU SoCs usually allow to determine core clock frequencies by
reading the Sample-At-Reset (SAR) register. The core clock consumer should
specify the desired clock by having the clock ID in its "clocks" phandle cell.
The following is a list of provided IDs and clock names on Armada 370/XP:
0 = tclk (Internal Bus clock)
1 = cpuclk (CPU clock)
2 = nbclk (L2 Cache clock)
3 = hclk (DRAM control clock)
4 = dramclk (DDR clock)
The following is a list of provided IDs and clock names on Kirkwood and Dove:
0 = tclk (Internal Bus clock)
1 = cpuclk (CPU0 clock)
2 = l2clk (L2 Cache clock derived from CPU0 clock)
3 = ddrclk (DDR controller clock derived from CPU0 clock)
Required properties:
- compatible : shall be one of the following:
"marvell,armada-370-core-clock" - For Armada 370 SoC core clocks
"marvell,armada-xp-core-clock" - For Armada XP SoC core clocks
"marvell,dove-core-clock" - for Dove SoC core clocks
"marvell,kirkwood-core-clock" - for Kirkwood SoC (except mv88f6180)
"marvell,mv88f6180-core-clock" - for Kirkwood MV88f6180 SoC
- reg : shall be the register address of the Sample-At-Reset (SAR) register
- #clock-cells : from common clock binding; shall be set to 1
Optional properties:
- clock-output-names : from common clock binding; allows overwrite default clock
output names ("tclk", "cpuclk", "l2clk", "ddrclk")
Example:
core_clk: core-clocks@d0214 {
compatible = "marvell,dove-core-clock";
reg = <0xd0214 0x4>;
#clock-cells = <1>;
};
spi0: spi@10600 {
compatible = "marvell,orion-spi";
/* ... */
/* get tclk from core clock provider */
clocks = <&core_clk 0>;
};
......@@ -54,3 +54,5 @@ config COMMON_CLK_MAX77686
This driver supports Maxim 77686 crystal oscillator clock.
endmenu
source "drivers/clk/mvebu/Kconfig"
......@@ -13,6 +13,7 @@ obj-$(CONFIG_PLAT_SPEAR) += spear/
obj-$(CONFIG_ARCH_U300) += clk-u300.o
obj-$(CONFIG_COMMON_CLK_VERSATILE) += versatile/
obj-$(CONFIG_ARCH_PRIMA2) += clk-prima2.o
obj-$(CONFIG_PLAT_ORION) += mvebu/
ifeq ($(CONFIG_COMMON_CLK), y)
obj-$(CONFIG_ARCH_MMP) += mmp/
endif
......
config MVEBU_CLK_CORE
bool
obj-$(CONFIG_MVEBU_CLK_CORE) += clk.o clk-core.o
This diff is collapsed.
/*
* * Marvell EBU clock core handling defined at reset
*
* Copyright (C) 2012 Marvell
*
* Gregory CLEMENT <gregory.clement@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#ifndef __MVEBU_CLK_CORE_H
#define __MVEBU_CLK_CORE_H
void __init mvebu_core_clk_init(void);
#endif
/*
* Marvell EBU SoC clock handling.
*
* Copyright (C) 2012 Marvell
*
* Gregory CLEMENT <gregory.clement@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/of_address.h>
#include <linux/clk/mvebu.h>
#include <linux/of.h>
#include "clk-core.h"
void __init mvebu_clocks_init(void)
{
mvebu_core_clk_init();
}
/*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef __CLK_MVEBU_H_
#define __CLK_MVEBU_H_
void __init mvebu_clocks_init(void);
#endif
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