Re: [PATCH v15 2/2] clk: clk-loongson2: add clock controller driver support
From: zhuyinbo
Date: Tue Mar 21 2023 - 22:07:38 EST
在 2023/3/22 上午7:42, Stephen Boyd 写道:
Quoting Yinbo Zhu (2023-03-21 06:07:10)
diff --git a/drivers/clk/clk-loongson2.c b/drivers/clk/clk-loongson2.c
new file mode 100644
index 000000000000..090810655511
--- /dev/null
+++ b/drivers/clk/clk-loongson2.c
@@ -0,0 +1,344 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Author: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
+ * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#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;
Why is this a global?
Normally, this should be an element in the structure, but since there is
only one
element, It is directly defined as a global variable for use by other
function.
+
+static const struct clk_parent_data pdata[] = {
+ { .fw_name = "ref_100m",},
+};
+
+static struct clk_hw *loongson2_clk_register(struct device *dev,
+ 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 */
Remove useless comment.
okay , I will remove it.
+ hw = devm_kzalloc(dev, 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 */
Remove useless comment.
okay, I will remove it.
+ ret = devm_clk_hw_register(dev, hw);
+ if (ret)
+ hw = ERR_PTR(ret);
+
+ return hw;
+}
+
[....]
+
+static const struct clk_ops loongson2_sata_clk_ops = {
+ .recalc_rate = loongson2_sata_recalc_rate,
+};
+
+static inline void loongson2_check_clk_hws(struct clk_hw *clks[], unsigned int count)
This needs to return an error instead of be void.
okay, I got it.
+{
+ 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 inline void loongson2_clocks_init(struct device *dev)
+{
+ struct clk_hw **hws;
+ struct clk_hw_onecell_data *clk_hw_data;
+ spinlock_t loongson2_clk_lock;
+
+ clk_hw_data = devm_kzalloc(dev, struct_size(clk_hw_data, hws, LOONGSON2_CLK_END),
+ GFP_KERNEL);
+ if (WARN_ON(!clk_hw_data))
+ return;
+
+ clk_hw_data->num = LOONGSON2_CLK_END;
+ hws = clk_hw_data->hws;
+
+ hws[LOONGSON2_NODE_PLL] = loongson2_clk_register(dev, "node_pll",
+ NULL,
+ &loongson2_node_clk_ops, 0);
+
+ hws[LOONGSON2_DDR_PLL] = loongson2_clk_register(dev, "ddr_pll",
+ NULL,
+ &loongson2_ddr_clk_ops, 0);
+
+ hws[LOONGSON2_DC_PLL] = loongson2_clk_register(dev, "dc_pll",
+ NULL,
+ &loongson2_dc_clk_ops, 0);
+
+ hws[LOONGSON2_PIX0_PLL] = loongson2_clk_register(dev, "pix0_pll",
+ NULL,
+ &loongson2_pix0_clk_ops, 0);
+
+ hws[LOONGSON2_PIX1_PLL] = loongson2_clk_register(dev, "pix1_pll",
+ NULL,
+ &loongson2_pix1_clk_ops, 0);
+
+ hws[LOONGSON2_BOOT_CLK] = loongson2_clk_register(dev, "boot",
+ NULL,
+ &loongson2_boot_clk_ops, 0);
+
+ hws[LOONGSON2_NODE_CLK] = clk_hw_register_divider(NULL, "node",
These should be devm_ variants so they're undone on failure.
okay , I will use devm_clk_hw_register_divider
+ "node_pll", 0,
+ loongson2_pll_base + 0x8, 0,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ /*
+ * The hda clk divisor in the upper 32bits and the clk-prodiver
+ * layer code doesn't support 64bit io operation thus a conversion
+ * is required that subtract shift by 32 and add 4byte to the hda
+ * address
+ */
+ hws[LOONGSON2_HDA_CLK] = clk_hw_register_divider(NULL, "hda",
+ "ddr_pll", 0,
+ loongson2_pll_base + 0x22, 12,
+ 7, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_GPU_CLK] = clk_hw_register_divider(NULL, "gpu",
+ "ddr_pll", 0,
+ loongson2_pll_base + 0x18, 22,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_DDR_CLK] = clk_hw_register_divider(NULL, "ddr",
+ "ddr_pll", 0,
+ loongson2_pll_base + 0x18, 0,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_GMAC_CLK] = clk_hw_register_divider(NULL, "gmac",
+ "dc_pll", 0,
+ loongson2_pll_base + 0x28, 22,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_DC_CLK] = clk_hw_register_divider(NULL, "dc",
+ "dc_pll", 0,
+ loongson2_pll_base + 0x28, 0,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_APB_CLK] = loongson2_clk_register(dev, "apb",
+ "gmac",
+ &loongson2_apb_clk_ops, 0);
+
+ hws[LOONGSON2_USB_CLK] = loongson2_clk_register(dev, "usb",
+ "gmac",
+ &loongson2_usb_clk_ops, 0);
+
+ hws[LOONGSON2_SATA_CLK] = loongson2_clk_register(dev, "sata",
+ "gmac",
+ &loongson2_sata_clk_ops, 0);
+
+ hws[LOONGSON2_PIX0_CLK] = clk_hw_register_divider(NULL, "pix0",
+ "pix0_pll", 0,
+ loongson2_pll_base + 0x38, 0, 6,
+ CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_PIX1_CLK] = clk_hw_register_divider(NULL, "pix1",
+ "pix1_pll", 0,
+ loongson2_pll_base + 0x48, 0, 6,
+ CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ loongson2_check_clk_hws(hws, LOONGSON2_CLK_END);
+
+ devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clk_hw_data);
Return this error code.
okay, I got it.
+}
+
+static const struct of_device_id loongson2_clk_match_table[] = {
+ { .compatible = "loongson,ls2k-clk" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, loongson2_clk_match_table);
This table can go next to the driver instead of be above probe.
okay, I will move it above loongson2_clk_driver.
+
+static int loongson2_clk_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+
+ loongson2_pll_base = devm_platform_ioremap_resource(pdev, 0);
+ if (!loongson2_pll_base)
Should be IS_ERR(loongson2_pll_base)
okay, I got it.
+ return PTR_ERR(loongson2_pll_base);
+
+ loongson2_clocks_init(dev);
Please inline this function here.
The loongson2_clocks_init had inline in this version, or do you mean something else ? Need to inline the probe?