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alistair23-linux/drivers/clk/mvebu/common.h

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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Marvell EBU SoC common clock handling
*
* Copyright (C) 2012 Marvell
*
* Gregory CLEMENT <gregory.clement@free-electrons.com>
* Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
* Andrew Lunn <andrew@lunn.ch>
*
*/
#ifndef __CLK_MVEBU_COMMON_H_
#define __CLK_MVEBU_COMMON_H_
#include <linux/kernel.h>
extern spinlock_t ctrl_gating_lock;
struct device_node;
struct coreclk_ratio {
int id;
const char *name;
};
struct coreclk_soc_desc {
u32 (*get_tclk_freq)(void __iomem *sar);
u32 (*get_cpu_freq)(void __iomem *sar);
void (*get_clk_ratio)(void __iomem *sar, int id, int *mult, int *div);
u32 (*get_refclk_freq)(void __iomem *sar);
bool (*is_sscg_enabled)(void __iomem *sar);
clk: mvebu: fix sscg node lookup Commit 15917b16022427c53755abff4dc7051f3076dd7a ("clk: mvebu: Fix clk frequency value if SSCG is enabled") introduced some logic in the common mvebu clock code to adjust the clock frequency according to the configuration of the SSCG. In order to do this, it looks up for a DT node called "sscg" and maps it before accessing the SSCG configuration register. However, the lookup is currently done using: sscg_np = of_find_node_by_name(np, "sscg"); where "np" is a pointer to the DT node of the clock for which we are calculating the adjusted frequency. This means that if the "sscg" node is *after* the clock node in the Device Tree, it works fine (and that's the case for Armada 370). However, if it turns out that the "sscg" node is *before* the clock node in the Device Tree, it won't work because the sscg node will not be found. What we really want here is a search of the entire Device Tree, not only starting from the clock node, so instead of passing "np" as first argument of of_find_node_by_name(), we simply need to pass NULL. Passing a non-NULL argument is typically used in a loop, so that the search for the next matching node starts right after the node that was matched. This makes the "np" argument to the kirkwood_fix_sscg_deviation() function unnecessary, which leads to further cleanups. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Fixes: 15917b1602242 ("clk: mvebu: Fix clk frequency value if SSCG is enabled") Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Link: https://lkml.kernel.org/r/1410880503-2322-1-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-09-16 09:15:03 -06:00
u32 (*fix_sscg_deviation)(u32 system_clk);
const struct coreclk_ratio *ratios;
int num_ratios;
};
struct clk_gating_soc_desc {
const char *name;
const char *parent;
int bit_idx;
unsigned long flags;
};
void __init mvebu_coreclk_setup(struct device_node *np,
const struct coreclk_soc_desc *desc);
void __init mvebu_clk_gating_setup(struct device_node *np,
const struct clk_gating_soc_desc *desc);
/*
* This function is shared among the Kirkwood, Armada 370, Armada XP
* and Armada 375 SoC
*/
clk: mvebu: fix sscg node lookup Commit 15917b16022427c53755abff4dc7051f3076dd7a ("clk: mvebu: Fix clk frequency value if SSCG is enabled") introduced some logic in the common mvebu clock code to adjust the clock frequency according to the configuration of the SSCG. In order to do this, it looks up for a DT node called "sscg" and maps it before accessing the SSCG configuration register. However, the lookup is currently done using: sscg_np = of_find_node_by_name(np, "sscg"); where "np" is a pointer to the DT node of the clock for which we are calculating the adjusted frequency. This means that if the "sscg" node is *after* the clock node in the Device Tree, it works fine (and that's the case for Armada 370). However, if it turns out that the "sscg" node is *before* the clock node in the Device Tree, it won't work because the sscg node will not be found. What we really want here is a search of the entire Device Tree, not only starting from the clock node, so instead of passing "np" as first argument of of_find_node_by_name(), we simply need to pass NULL. Passing a non-NULL argument is typically used in a loop, so that the search for the next matching node starts right after the node that was matched. This makes the "np" argument to the kirkwood_fix_sscg_deviation() function unnecessary, which leads to further cleanups. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Fixes: 15917b1602242 ("clk: mvebu: Fix clk frequency value if SSCG is enabled") Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Link: https://lkml.kernel.org/r/1410880503-2322-1-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-09-16 09:15:03 -06:00
u32 kirkwood_fix_sscg_deviation(u32 system_clk);
#endif