[PATCH v13 2/2] clk: clk-loongson2: add clock controller driver support
From: Yinbo Zhu
Date: Tue Mar 07 2023 - 06:51:50 EST
This driver provides support for clock controller on Loongson-2 SoC,
the Loongson-2 SoC uses a 100MHz clock as the PLL reference clock,
there are five independent PLLs inside, each of which PLL can
provide up to three sets of frequency dependent clock outputs.
Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
---
Change in v13:
1. Add the Loongson-2 boot clk support.
Change in v12:
1. Change driver register way that use platform driver register.
Change in v11:
1. Remove the repetitive COMMON_CLK config in loongarch Kconfig.
2. Fixup the help paragraph descprition in COMMON_CLK_LOONGSON2.
3. Drop the <linux/clkdev.h>.
4. Drop the cast in clock driver.
5. Use div_u64() replace do_div().
6. Inline this function for loongson2_check_clk_hws.
7. Fixup the comma deposition on the loongson2_check_clk_hws.
8. Drop the loongson2_obtain_fixed_clk_hw and rework this driver
use clk_parent_data and the 'fw_name'.
Change in v10:
1. Detach of_clk_init to another patch.
Change in v9:
1. Add all history changelog information.
Change in v8:
1. Remove the flag "CLK_IS_BASIC".
Change in v7:
1. Adjust position alphabetically in Kconfig and Makefile.
2. Add static for loongson2_pll_base.
3. Move other file-scope variables in probe.
Change in v6:
1. NO change, but other patch in this series of patches has
changes.
Change in v5:
1. Replace loongson2 with Loongson-2 in commit info.
2. Replace Loongson2 with Loongson-2 in binding and
Kconfig file.
3. Replace soc with SoC.
Change in v4:
1. Fixup clock-names that replace "xxx-clk" with "xxx".
Change in v3:
1. NO change, but other patch in this series of patches has
changes.
Change in v2:
1. Update the include filename.
2. Change string from refclk/REFCLK to ref/REF.
MAINTAINERS | 1 +
drivers/clk/Kconfig | 9 +
drivers/clk/Makefile | 1 +
drivers/clk/clk-loongson2.c | 355 ++++++++++++++++++++++++++++++++++++
4 files changed, 366 insertions(+)
create mode 100644 drivers/clk/clk-loongson2.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 8d5bc223f3053..2334623052875 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12121,6 +12121,7 @@ M: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
L: linux-clk@xxxxxxxxxxxxxxx
S: Maintained
F: Documentation/devicetree/bindings/clock/loongson,ls2k-clk.yaml
+F: drivers/clk/clk-loongson2.c
F: include/dt-bindings/clock/loongson,ls2k-clk.h
LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index b6c5bf69a2b2c..27c5fa02916a6 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
+ 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/Makefile b/drivers/clk/Makefile
index e3ca0d058a256..b298c5dabc1a4 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_COMMON_CLK_K210) += clk-k210.o
obj-$(CONFIG_LMK04832) += clk-lmk04832.o
obj-$(CONFIG_COMMON_CLK_LAN966X) += clk-lan966x.o
obj-$(CONFIG_COMMON_CLK_LOCHNAGAR) += clk-lochnagar.o
+obj-$(CONFIG_COMMON_CLK_LOONGSON2) += clk-loongson2.o
obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o
obj-$(CONFIG_COMMON_CLK_MAX9485) += clk-max9485.o
obj-$(CONFIG_ARCH_MILBEAUT_M10V) += clk-milbeaut.o
diff --git a/drivers/clk/clk-loongson2.c b/drivers/clk/clk-loongson2.c
new file mode 100644
index 0000000000000..c24334b19ea70
--- /dev/null
+++ b/drivers/clk/clk-loongson2.c
@@ -0,0 +1,355 @@
+// 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/of.h>
+#include <linux/of_address.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/platform_device.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", },
+};
+
+static struct clk_hw *loongson2_clk_register(struct device_node *np,
+ 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);
+ 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;
+
+ 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);
+
+ 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 const struct clk_ops loongson2_node_clk_ops = {
+ .recalc_rate = loongson2_node_recalc_rate,
+};
+
+static unsigned long loongson2_ddr_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_pll_rate(0x10, parent_rate);
+}
+
+static const struct clk_ops loongson2_ddr_clk_ops = {
+ .recalc_rate = loongson2_ddr_recalc_rate,
+};
+
+static unsigned long loongson2_dc_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_pll_rate(0x20, parent_rate);
+}
+
+static const struct clk_ops loongson2_dc_clk_ops = {
+ .recalc_rate = loongson2_dc_recalc_rate,
+};
+
+static unsigned long loongson2_pix0_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_pll_rate(0x30, parent_rate);
+}
+
+static const struct clk_ops loongson2_pix0_clk_ops = {
+ .recalc_rate = loongson2_pix0_recalc_rate,
+};
+
+static unsigned long loongson2_pix1_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_pll_rate(0x40, parent_rate);
+}
+
+static const struct clk_ops loongson2_pix1_clk_ops = {
+ .recalc_rate = loongson2_pix1_recalc_rate,
+};
+
+static unsigned long loongson2_calc_rate(unsigned long rate,
+ int shift, int width)
+{
+ u64 val;
+ u32 mult;
+
+ val = readq(loongson2_pll_base + 0x50);
+
+ mult = (val >> shift) & clk_div_mask(width);
+
+ return div_u64((u64)rate * (mult + 1), 8);
+}
+
+static unsigned long loongson2_boot_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_rate(parent_rate,
+ LOONGSON2_BOOT_FREQSCALE_SHIFT,
+ LOONGSON2_BOOT_FREQSCALE_WIDTH);
+}
+
+static const struct clk_ops loongson2_boot_clk_ops = {
+ .recalc_rate = loongson2_boot_recalc_rate,
+};
+
+static unsigned long loongson2_apb_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_rate(parent_rate,
+ LOONGSON2_APB_FREQSCALE_SHIFT,
+ LOONGSON2_APB_FREQSCALE_WIDTH);
+}
+
+static const struct clk_ops loongson2_apb_clk_ops = {
+ .recalc_rate = loongson2_apb_recalc_rate,
+};
+
+static unsigned long loongson2_usb_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_rate(parent_rate,
+ LOONGSON2_USB_FREQSCALE_SHIFT,
+ LOONGSON2_USB_FREQSCALE_WIDTH);
+}
+
+static const struct clk_ops loongson2_usb_clk_ops = {
+ .recalc_rate = loongson2_usb_recalc_rate,
+};
+
+static unsigned long loongson2_sata_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return loongson2_calc_rate(parent_rate,
+ LOONGSON2_SATA_FREQSCALE_SHIFT,
+ LOONGSON2_SATA_FREQSCALE_WIDTH);
+}
+
+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)
+{
+ 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)
+{
+ struct clk_hw **hws;
+ struct clk_hw_onecell_data *clk_hw_data;
+ spinlock_t loongson2_clk_lock;
+
+ loongson2_pll_base = of_iomap(np, 0);
+
+ if (!loongson2_pll_base) {
+ pr_err("clk: unable to map loongson2 clk registers\n");
+ return;
+ }
+
+ clk_hw_data = kzalloc(struct_size(clk_hw_data, hws, LOONGSON2_CLK_END),
+ GFP_KERNEL);
+ if (WARN_ON(!clk_hw_data))
+ goto err;
+
+ clk_hw_data->num = LOONGSON2_CLK_END;
+ hws = clk_hw_data->hws;
+
+ hws[LOONGSON2_NODE_PLL] = loongson2_clk_register(np, "node_pll",
+ NULL,
+ &loongson2_node_clk_ops, 0);
+
+ hws[LOONGSON2_DDR_PLL] = loongson2_clk_register(np, "ddr_pll",
+ NULL,
+ &loongson2_ddr_clk_ops, 0);
+
+ hws[LOONGSON2_DC_PLL] = loongson2_clk_register(np, "dc_pll",
+ NULL,
+ &loongson2_dc_clk_ops, 0);
+
+ hws[LOONGSON2_PIX0_PLL] = loongson2_clk_register(np, "pix0_pll",
+ NULL,
+ &loongson2_pix0_clk_ops, 0);
+
+ hws[LOONGSON2_PIX1_PLL] = loongson2_clk_register(np, "pix1_pll",
+ NULL,
+ &loongson2_pix1_clk_ops, 0);
+
+ hws[LOONGSON2_BOOT_CLK] = loongson2_clk_register(np, "boot",
+ NULL,
+ &loongson2_boot_clk_ops, 0);
+
+ hws[LOONGSON2_NODE_CLK] = clk_hw_register_divider(NULL, "node",
+ "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(NULL, "apb",
+ "gmac",
+ &loongson2_apb_clk_ops, 0);
+
+ hws[LOONGSON2_USB_CLK] = loongson2_clk_register(NULL, "usb",
+ "gmac",
+ &loongson2_usb_clk_ops, 0);
+
+ hws[LOONGSON2_SATA_CLK] = loongson2_clk_register(NULL, "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);
+
+ of_clk_add_hw_provider(np, of_clk_hw_onecell_get, clk_hw_data);
+
+err:
+ iounmap(loongson2_pll_base);
+}
+
+static const struct of_device_id loongson2_clk_match_table[] = {
+ { .compatible = "loongson,ls2k-clk" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, loongson2_clk_match_table);
+
+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;
+}
+
+static struct platform_driver loongson2_clk_driver = {
+ .probe = loongson2_clk_probe,
+ .driver = {
+ .name = "loongson2-clk",
+ .of_match_table = loongson2_clk_match_table,
+ },
+};
+module_platform_driver(loongson2_clk_driver);
+
+MODULE_DESCRIPTION("Loongson2 clock driver");
+MODULE_LICENSE("GPL");
--
2.31.1