[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1bac2baccd4de561944c4a3f8454f7d3.sboyd@kernel.org>
Date: Mon, 20 Mar 2023 13:17:17 -0700
From: Stephen Boyd <sboyd@...nel.org>
To: Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
Michael Turquette <mturquette@...libre.com>,
Rob Herring <robh+dt@...nel.org>,
Yinbo Zhu <zhuyinbo@...ngson.cn>, devicetree@...r.kernel.org,
linux-clk@...r.kernel.org, linux-kernel@...r.kernel.org
Cc: Jianmin Lv <lvjianmin@...ngson.cn>, wanghongliang@...ngson.cn,
Liu Peibao <liupeibao@...ngson.cn>,
loongson-kernel@...ts.loongnix.cn, Yinbo Zhu <zhuyinbo@...ngson.cn>
Subject: Re: [PATCH v14 2/2] clk: clk-loongson2: add clock controller driver support
Quoting Yinbo Zhu (2023-03-18 00:53:40)
> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> index 1eef05bb1f99..c0f32d9c1cc4 100644
> --- a/drivers/clk/Kconfig
> +++ b/drivers/clk/Kconfig
> @@ -325,6 +325,15 @@ config COMMON_CLK_LOCHNAGAR
> This driver supports the clocking features of the Cirrus Logic
> Lochnagar audio development board.
>
> +config COMMON_CLK_LOONGSON2
> + bool "Clock driver for Loongson-2 SoC"
> + depends on COMMON_CLK && OF
It doesn't depend on OF to build, right? If so, remove it. Also, this is
within the 'if COMMON_CLK' section of this file, so the 'depends on
COMMON_CLK' is redundant and should be removed.
> + help
> + This driver provides support for clock controller on Loongson-2 SoC.
> + The clock controller can generates and supplies clock to various
> + peripherals within the SoC.
> + Say Y here to support Loongson-2 SoC clock driver.
> +
> config COMMON_CLK_NXP
> def_bool COMMON_CLK && (ARCH_LPC18XX || ARCH_LPC32XX)
> select REGMAP_MMIO if ARCH_LPC32XX
> diff --git a/drivers/clk/clk-loongson2.c b/drivers/clk/clk-loongson2.c
> new file mode 100644
> index 000000000000..c423932b626d
> --- /dev/null
> +++ b/drivers/clk/clk-loongson2.c
> @@ -0,0 +1,356 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Author: Yinbo Zhu <zhuyinbo@...ngson.cn>
> + * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
> + */
> +
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/of.h>
Don't think this include will be needed.
> +#include <linux/of_address.h>
Don't include this.
> +#include <linux/clk-provider.h>
> +#include <linux/slab.h>
> +#include <linux/clk.h>
Drop this include. This isn't a clk consumer.
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/io-64-nonatomic-lo-hi.h>
> +#include <dt-bindings/clock/loongson,ls2k-clk.h>
> +
> +#define LOONGSON2_PLL_MULT_SHIFT 32
> +#define LOONGSON2_PLL_MULT_WIDTH 10
> +#define LOONGSON2_PLL_DIV_SHIFT 26
> +#define LOONGSON2_PLL_DIV_WIDTH 6
> +#define LOONGSON2_APB_FREQSCALE_SHIFT 20
> +#define LOONGSON2_APB_FREQSCALE_WIDTH 3
> +#define LOONGSON2_USB_FREQSCALE_SHIFT 16
> +#define LOONGSON2_USB_FREQSCALE_WIDTH 3
> +#define LOONGSON2_SATA_FREQSCALE_SHIFT 12
> +#define LOONGSON2_SATA_FREQSCALE_WIDTH 3
> +#define LOONGSON2_BOOT_FREQSCALE_SHIFT 8
> +#define LOONGSON2_BOOT_FREQSCALE_WIDTH 3
> +
> +static void __iomem *loongson2_pll_base;
> +
> +static const struct clk_parent_data pdata[] = {
> + { .fw_name = "ref_100m", .name = "ref_clk", },
Are you mainintain backwards compatibility? If not, which I believe is
the case, drop .name assignment.
> +};
> +
> +static struct clk_hw *loongson2_clk_register(struct device_node *np,
Take a struct device instead.
> + const char *name,
> + const char *parent_name,
> + const struct clk_ops *ops,
> + unsigned long flags)
> +{
> + int ret;
> + struct clk_hw *hw;
> + struct clk_init_data init;
> +
> + /* allocate the divider */
> + hw = kzalloc(sizeof(*hw), GFP_KERNEL);
> + if (!hw)
> + return ERR_PTR(-ENOMEM);
> +
> + init.name = name;
> + init.ops = ops;
> + init.flags = flags;
> + init.num_parents = 1;
> +
> + if (!parent_name)
> + init.parent_data = pdata;
> + else
> + init.parent_names = &parent_name;
> +
> + hw->init = &init;
> +
> + /* register the clock */
> + ret = of_clk_hw_register(np, hw);
Use devm_clk_hw_register()
> + if (ret) {
> + kfree(hw);
> + hw = ERR_PTR(ret);
> + }
> +
> + return hw;
> +}
> +
> +static unsigned long loongson2_calc_pll_rate(int offset, unsigned long rate)
> +{
> + u64 val;
> + u32 mult = 1, div = 1;
Why are these initialized?
> +
> + val = readq(loongson2_pll_base + offset);
> +
> + mult = (val >> LOONGSON2_PLL_MULT_SHIFT) &
> + clk_div_mask(LOONGSON2_PLL_MULT_WIDTH);
> + div = (val >> LOONGSON2_PLL_DIV_SHIFT) &
> + clk_div_mask(LOONGSON2_PLL_DIV_WIDTH);
They're overwritten here.
> +
> + return div_u64((u64)rate * mult, div);
> +}
> +
> +static unsigned long loongson2_node_recalc_rate(struct clk_hw *hw,
> + unsigned long parent_rate)
> +{
> + return loongson2_calc_pll_rate(0x0, parent_rate);
> +}
[...]
> +
> +static inline void loongson2_check_clk_hws(struct clk_hw *clks[], unsigned int count)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < count; i++)
> + if (IS_ERR(clks[i]))
> + pr_err("Loongson2 clk %u: register failed with %ld\n",
> + i, PTR_ERR(clks[i]));
> +}
> +
> +static void loongson2_clocks_init(struct device_node *np)
Inline this function at the caller.
> +{
> + struct clk_hw **hws;
> + struct clk_hw_onecell_data *clk_hw_data;
> + spinlock_t loongson2_clk_lock;
> +
> + loongson2_pll_base = of_iomap(np, 0);
Use platform device APIs.
> +
> + if (!loongson2_pll_base) {
> + pr_err("clk: unable to map loongson2 clk registers\n");
Drop error messages when mapping.
> + return;
> + }
> +
> + clk_hw_data = kzalloc(struct_size(clk_hw_data, hws, LOONGSON2_CLK_END),
Use devm_kzalloc()
> + GFP_KERNEL);
> + if (WARN_ON(!clk_hw_data))
> + goto err;
> +
[...]
> +
> +static int loongson2_clk_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> +
> + loongson2_clocks_init(np);
> +
> + return 0;
> +}
> +
Powered by blists - more mailing lists