[PATCH v1 2/3] clk: clk-loongson2: add clock controller driver support
From: Yinbo Zhu
Date: Tue Oct 18 2022 - 21:06:14 EST
This driver provides support for clock controller on Loongson2 SoC
, the Loongson2 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>
---
MAINTAINERS | 1 +
arch/loongarch/Kconfig | 1 +
arch/loongarch/kernel/time.c | 2 +
drivers/clk/Kconfig | 9 ++
drivers/clk/Makefile | 1 +
drivers/clk/clk-loongson2.c | 285 +++++++++++++++++++++++++++++++++++
6 files changed, 299 insertions(+)
create mode 100644 drivers/clk/clk-loongson2.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 3db469f51d74..4caea1d99310 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11918,6 +11918,7 @@ LOONGSON2 SOC SERIES CLOCK DRIVER
M: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
L: linux-clk@xxxxxxxxxxxxxxx
S: Maintained
+F: drivers/clk/clk-loongson2.c
F: include/dt-bindings/clock/loongson2-clock.h
LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 26aeb1408e56..8b65f349cd6e 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -122,6 +122,7 @@ config LOONGARCH
select USE_PERCPU_NUMA_NODE_ID
select USER_STACKTRACE_SUPPORT
select ZONE_DMA32
+ select COMMON_CLK
config 32BIT
bool
diff --git a/arch/loongarch/kernel/time.c b/arch/loongarch/kernel/time.c
index 74f34c74679a..0d8b37763086 100644
--- a/arch/loongarch/kernel/time.c
+++ b/arch/loongarch/kernel/time.c
@@ -12,6 +12,7 @@
#include <linux/kernel.h>
#include <linux/sched_clock.h>
#include <linux/spinlock.h>
+#include <linux/of_clk.h>
#include <asm/cpu-features.h>
#include <asm/loongarch.h>
@@ -214,6 +215,7 @@ int __init constant_clocksource_init(void)
void __init time_init(void)
{
+ of_clk_init(NULL);
#ifdef CONFIG_TIMER_PROBE
timer_probe();
#endif
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 48f8f4221e21..88620f86373f 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -428,6 +428,15 @@ config COMMON_CLK_K210
help
Support for the Canaan Kendryte K210 RISC-V SoC clocks.
+config COMMON_CLK_LOONGSON2
+ bool "Clock driver for Loongson2 SoC"
+ depends on COMMON_CLK && OF
+ help
+ This driver provides support for Clock Controller that base on
+ Common Clock Framework Controller (CCF) on Loongson2 SoC. The
+ Clock Controller can generates and supplies clock to various
+ peripherals within the SoC.
+
source "drivers/clk/actions/Kconfig"
source "drivers/clk/analogbits/Kconfig"
source "drivers/clk/baikal-t1/Kconfig"
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index d5db170d38d2..8ccc7436052f 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -75,6 +75,7 @@ obj-$(CONFIG_COMMON_CLK_RS9_PCIE) += clk-renesas-pcie.o
obj-$(CONFIG_COMMON_CLK_VC5) += clk-versaclock5.o
obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o
obj-$(CONFIG_COMMON_CLK_XGENE) += clk-xgene.o
+obj-$(CONFIG_COMMON_CLK_LOONGSON2) += clk-loongson2.o
# please keep this section sorted lexicographically by directory path name
obj-y += actions/
diff --git a/drivers/clk/clk-loongson2.c b/drivers/clk/clk-loongson2.c
new file mode 100644
index 000000000000..7fe71cac5970
--- /dev/null
+++ b/drivers/clk/clk-loongson2.c
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Author: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
+ * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
+ */
+
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <dt-bindings/clock/loongson2-clock.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/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
+
+void __iomem *loongson2_pll_base;
+static DEFINE_SPINLOCK(loongson2_clk_lock);
+static struct clk_hw **hws;
+static struct clk_hw_onecell_data *clk_hw_data;
+
+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 */
+ hw = kzalloc(sizeof(*hw), GFP_KERNEL);
+ if (!hw)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = ops;
+ init.flags = flags | CLK_IS_BASIC;
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+ hw->init = &init;
+
+ /* register the clock */
+ ret = clk_hw_register(dev, hw);
+ if (ret) {
+ kfree(hw);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}
+
+static struct clk_hw *loongson2_clk_pll_register(const char *name,
+ const char *parent, void __iomem *reg)
+{
+ u64 val;
+ u32 mult = 1, div = 1;
+
+ val = readq((void *)reg);
+
+ 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 clk_hw_register_fixed_factor(NULL, name, parent,
+ CLK_SET_RATE_PARENT, mult, div);
+}
+
+static unsigned long loongson2_apb_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u64 val;
+ u32 mult;
+ unsigned long rate;
+
+ val = readq((void *)(loongson2_pll_base + 0x50));
+
+ mult = (val >> LOONGSON2_APB_FREQSCALE_SHIFT) &
+ clk_div_mask(LOONGSON2_APB_FREQSCALE_WIDTH);
+
+ rate = parent_rate * (mult + 1);
+ do_div(rate, 8);
+
+ return rate;
+}
+
+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)
+{
+ u64 val;
+ u32 mult;
+ unsigned long rate;
+
+ val = readq((void *)(loongson2_pll_base + 0x50));
+
+ mult = (val >> LOONGSON2_USB_FREQSCALE_SHIFT) &
+ clk_div_mask(LOONGSON2_USB_FREQSCALE_WIDTH);
+
+ rate = parent_rate * (mult + 1);
+ do_div(rate, 8);
+
+ return rate;
+}
+
+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)
+{
+ u64 val;
+ u32 mult;
+ unsigned long rate;
+
+ val = readq((void *)(loongson2_pll_base + 0x50));
+
+ mult = (val >> LOONGSON2_SATA_FREQSCALE_SHIFT) &
+ clk_div_mask(LOONGSON2_SATA_FREQSCALE_WIDTH);
+
+ rate = parent_rate * (mult + 1);
+ do_div(rate, 8);
+
+ return rate;
+}
+
+static const struct clk_ops loongson2_sata_clk_ops = {
+ .recalc_rate = loongson2_sata_recalc_rate,
+};
+
+static 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 struct clk_hw *loongson2_obtain_fixed_clk_hw(
+ struct device_node *np,
+ const char *name)
+{
+ struct clk *clk;
+
+ clk = of_clk_get_by_name(np, name);
+ if (IS_ERR(clk))
+ return ERR_PTR(-ENOENT);
+
+ return __clk_get_hw(clk);
+}
+
+static void __init loongson2_clocks_init(struct device_node *np)
+{
+ loongson2_pll_base = of_iomap(np, 0);
+
+ if (!loongson2_pll_base) {
+ pr_err("clk: unable to map loongson2 clk registers\n");
+ goto err;
+ }
+
+ 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_REFCLK_100M] = loongson2_obtain_fixed_clk_hw(np,
+ "refclk_100m");
+
+ hws[LOONGSON2_NODE_PLL] = loongson2_clk_pll_register("node_pll_clk",
+ "refclk_100m",
+ loongson2_pll_base);
+
+ hws[LOONGSON2_DDR_PLL] = loongson2_clk_pll_register("ddr_pll_clk",
+ "refclk_100m",
+ loongson2_pll_base + 0x10);
+
+ hws[LOONGSON2_DC_PLL] = loongson2_clk_pll_register("dc_pll_clk",
+ "refclk_100m",
+ loongson2_pll_base + 0x20);
+
+ hws[LOONGSON2_PIX0_PLL] = loongson2_clk_pll_register("pix0_pll_clk",
+ "refclk_100m",
+ loongson2_pll_base + 0x30);
+
+ hws[LOONGSON2_PIX1_PLL] = loongson2_clk_pll_register("pix1_pll_clk",
+ "refclk_100m",
+ loongson2_pll_base + 0x40);
+
+ hws[LOONGSON2_NODE_CLK] = clk_hw_register_divider(NULL, "node_clk",
+ "node_pll_clk", 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_clk",
+ "ddr_pll_clk", 0,
+ loongson2_pll_base + 0x22, 12,
+ 7, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_GPU_CLK] = clk_hw_register_divider(NULL, "gpu_clk",
+ "ddr_pll_clk", 0,
+ loongson2_pll_base + 0x18, 22,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_DDR_CLK] = clk_hw_register_divider(NULL, "ddr_clk",
+ "ddr_pll_clk", 0,
+ loongson2_pll_base + 0x18, 0,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_GMAC_CLK] = clk_hw_register_divider(NULL, "gmac_clk",
+ "dc_pll_clk", 0,
+ loongson2_pll_base + 0x28, 22,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_DC_CLK] = clk_hw_register_divider(NULL, "dc_clk",
+ "dc_pll_clk", 0,
+ loongson2_pll_base + 0x28, 0,
+ 6, CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_APB_CLK] = loongson2_clk_register(NULL, "apb_clk",
+ "gmac_clk",
+ &loongson2_apb_clk_ops, 0);
+
+ hws[LOONGSON2_USB_CLK] = loongson2_clk_register(NULL, "usb_clk",
+ "gmac_clk",
+ &loongson2_usb_clk_ops, 0);
+
+ hws[LOONGSON2_SATA_CLK] = loongson2_clk_register(NULL, "sata_clk",
+ "gmac_clk",
+ &loongson2_sata_clk_ops, 0);
+
+ hws[LOONGSON2_PIX0_CLK] = clk_hw_register_divider(NULL, "pix0_clk",
+ "pix0_pll_clk", 0,
+ loongson2_pll_base + 0x38, 0, 6,
+ CLK_DIVIDER_ONE_BASED,
+ &loongson2_clk_lock);
+
+ hws[LOONGSON2_PIX1_CLK] = clk_hw_register_divider(NULL, "pix1_clk",
+ "pix1_pll_clk", 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);
+}
+
+CLK_OF_DECLARE(loongson2_clk, "loongson,ls2k-clk", loongson2_clocks_init);
--
2.20.1