[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <564F8869.6040307@gmail.com>
Date: Fri, 20 Nov 2015 21:54:01 +0100
From: Sebastian Hesselbarth <sebastian.hesselbarth@...il.com>
To: Jisheng Zhang <jszhang@...vell.com>, robh+dt@...nel.org,
pawel.moll@....com, mark.rutland@....com,
ijc+devicetree@...lion.org.uk, galak@...eaurora.org,
catalin.marinas@....com, will.deacon@....com,
mturquette@...libre.com, sboyd@...eaurora.org,
antoine.tenart@...e-electrons.com
Cc: devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-arm-kernel@...ts.infradead.org, linux-clk@...r.kernel.org
Subject: Re: [PATCH v2 2/6] clk: berlin: add common clk driver for newer SoCs
On 20.11.2015 09:42, Jisheng Zhang wrote:
> Add common clk driver for Marvell SoCs newer than BG2, BG2CD, BG2Q.
> berlin_clk_setup() is provided to setup and register such kind of clks.
>
> Signed-off-by: Jisheng Zhang <jszhang@...vell.com>
> ---
> drivers/clk/berlin/Makefile | 2 +-
> drivers/clk/berlin/clk.c | 203 ++++++++++++++++++++++++++++++++++++++++++++
> drivers/clk/berlin/clk.h | 33 +++++++
> 3 files changed, 237 insertions(+), 1 deletion(-)
> create mode 100644 drivers/clk/berlin/clk.c
> create mode 100644 drivers/clk/berlin/clk.h
>
> diff --git a/drivers/clk/berlin/Makefile b/drivers/clk/berlin/Makefile
> index eee42b0..ee2e09d 100644
> --- a/drivers/clk/berlin/Makefile
> +++ b/drivers/clk/berlin/Makefile
> @@ -1,5 +1,5 @@
> obj-y += berlin2-avpll.o berlin2-pll.o berlin2-div.o
> -obj-y += pll.o
> +obj-y += pll.o clk.o
Same comment about the naming convention.
> obj-$(CONFIG_MACH_BERLIN_BG2) += bg2.o
> obj-$(CONFIG_MACH_BERLIN_BG2CD) += bg2.o
> obj-$(CONFIG_MACH_BERLIN_BG2Q) += bg2q.o
> diff --git a/drivers/clk/berlin/clk.c b/drivers/clk/berlin/clk.c
> new file mode 100644
> index 0000000..70f2b9d
> --- /dev/null
> +++ b/drivers/clk/berlin/clk.c
> @@ -0,0 +1,203 @@
> +/*
> + * Copyright (c) 2015 Marvell Technology Group Ltd.
> + *
> + * Author: Jisheng Zhang <jszhang@...vell.com>
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/slab.h>
> +
> +#include "clk.h"
> +
> +#define CLKEN (1 << 0)
#define CLKEN BIT(0)
> +#define CLKPLLSEL_MASK 7
Please use hex numbers for the mask.
> +#define CLKPLLSEL_SHIFT 1
> +#define CLKPLLSWITCH (1 << 4)
> +#define CLKSWITCH (1 << 5)
> +#define CLKD3SWITCH (1 << 6)
BIT() again.
> +#define CLKSEL_MASK 7
Hex again.
> +#define CLKSEL_SHIFT 7
> +
> +#define CLK_SOURCE_MAX 5
> +
> +struct berlin_clk {
> + struct clk_hw hw;
> + void __iomem *base;
> +};
> +
> +#define to_berlin_clk(hw) container_of(hw, struct berlin_clk, hw)
> +
> +static u8 clk_div[] = {1, 2, 4, 6, 8, 12, 1, 1};
Hmm, this pretty much looks like berlin2-div dividers...
> +static unsigned long berlin_clk_recalc_rate(struct clk_hw *hw,
> + unsigned long parent_rate)
> +{
> + u32 val, divider;
> + struct berlin_clk *clk = to_berlin_clk(hw);
> +
> + val = readl_relaxed(clk->base);
> + if (val & CLKD3SWITCH)
> + divider = 3;
and this looks like berlin2-div structure, doesn't it?
Again, please reuse what is already available.
Sebastian
> + else {
> + if (val & CLKSWITCH) {
> + val >>= CLKSEL_SHIFT;
> + val &= CLKSEL_MASK;
> + divider = clk_div[val];
> + } else
> + divider = 1;
> + }
> +
> + return parent_rate / divider;
> +}
> +
> +static u8 berlin_clk_get_parent(struct clk_hw *hw)
> +{
> + u32 val;
> + struct berlin_clk *clk = to_berlin_clk(hw);
> +
> + val = readl_relaxed(clk->base);
> + if (val & CLKPLLSWITCH) {
> + val >>= CLKPLLSEL_SHIFT;
> + val &= CLKPLLSEL_MASK;
> + return val;
> + }
> +
> + return 0;
> +}
> +
> +static int berlin_clk_enable(struct clk_hw *hw)
> +{
> + u32 val;
> + struct berlin_clk *clk = to_berlin_clk(hw);
> +
> + val = readl_relaxed(clk->base);
> + val |= CLKEN;
> + writel_relaxed(val, clk->base);
> +
> + return 0;
> +}
> +
> +static void berlin_clk_disable(struct clk_hw *hw)
> +{
> + u32 val;
> + struct berlin_clk *clk = to_berlin_clk(hw);
> +
> + val = readl_relaxed(clk->base);
> + val &= ~CLKEN;
> + writel_relaxed(val, clk->base);
> +}
> +
> +static int berlin_clk_is_enabled(struct clk_hw *hw)
> +{
> + u32 val;
> + struct berlin_clk *clk = to_berlin_clk(hw);
> +
> + val = readl_relaxed(clk->base);
> + val &= CLKEN;
> +
> + return val ? 1 : 0;
> +}
> +
> +static const struct clk_ops berlin_clk_ops = {
> + .recalc_rate = berlin_clk_recalc_rate,
> + .get_parent = berlin_clk_get_parent,
> + .enable = berlin_clk_enable,
> + .disable = berlin_clk_disable,
> + .is_enabled = berlin_clk_is_enabled,
> +};
> +
> +static struct clk * __init
> +berlin_clk_register(const char *name, int num_parents,
> + const char **parent_names, unsigned long flags,
> + void __iomem *base)
> +{
> + struct clk *clk;
> + struct berlin_clk *bclk;
> + struct clk_init_data init;
> +
> + bclk = kzalloc(sizeof(*bclk), GFP_KERNEL);
> + if (!bclk)
> + return ERR_PTR(-ENOMEM);
> +
> + init.name = name;
> + init.ops = &berlin_clk_ops;
> + init.parent_names = parent_names;
> + init.num_parents = num_parents;
> + init.flags = flags;
> +
> + bclk->base = base;
> + bclk->hw.init = &init;
> +
> + clk = clk_register(NULL, &bclk->hw);
> + if (IS_ERR(clk))
> + kfree(bclk);
> +
> + return clk;
> +}
> +
> +void __init berlin_clk_setup(struct device_node *np,
> + const struct clk_desc *descs,
> + struct clk_onecell_data *clk_data,
> + int n)
> +{
> + int i, ret, num_parents;
> + void __iomem *base;
> + struct clk **clks;
> + const char *parent_names[CLK_SOURCE_MAX];
> +
> + num_parents = of_clk_get_parent_count(np);
> + if (num_parents <= 0 || num_parents > CLK_SOURCE_MAX)
> + return;
> +
> + of_clk_parent_fill(np, parent_names, num_parents);
> +
> + clks = kcalloc(n, sizeof(struct clk *), GFP_KERNEL);
> + if (!clks)
> + return;
> +
> + base = of_iomap(np, 0);
> + if (WARN_ON(!base))
> + goto err_iomap;
> +
> + for (i = 0; i < n; i++) {
> + struct clk *clk;
> +
> + clk = berlin_clk_register(descs[i].name,
> + num_parents, parent_names,
> + descs[i].flags,
> + base + descs[i].offset);
> + if (WARN_ON(IS_ERR(clks[i])))
> + goto err_clk_register;
> + clks[i] = clk;
> + }
> +
> + clk_data->clks = clks;
> + clk_data->clk_num = i;
> +
> + ret = of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
> + if (WARN_ON(ret))
> + goto err_clk_register;
> + return;
> +
> +err_clk_register:
> + for (i = 0; i < n; i++)
> + clk_unregister(clks[i]);
> + iounmap(base);
> +err_iomap:
> + kfree(clks);
> +}
> diff --git a/drivers/clk/berlin/clk.h b/drivers/clk/berlin/clk.h
> new file mode 100644
> index 0000000..5e5680e
> --- /dev/null
> +++ b/drivers/clk/berlin/clk.h
> @@ -0,0 +1,33 @@
> +/*
> + * Copyright (c) 2015 Marvell Technology Group Ltd.
> + *
> + * Author: Jisheng Zhang <jszhang@...vell.com>
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#ifndef __BERLIN_CLK_H
> +#define __BERLIN_CLK_H
> +
> +struct clk_desc {
> + const char *name;
> + u32 offset;
> + unsigned long flags;
> +};
> +
> +void __init berlin_clk_setup(struct device_node *np,
> + const struct clk_desc *desc,
> + struct clk_onecell_data *clk_data,
> + int n);
> +
> +#endif
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists