[PATCH v4 7/8] clk: Loongson: Add Loongson-1A clock support

[Binbin Zhou <zhoubb@lemote.com>]

This patch adds clock support to Loongson-1A SoC

There is a workaround that Loongson-1A's PLL register is written only,
so we just set it with a fixed value.

Signed-off-by: Binbin Zhou <zhoubb@lemote.com>
Signed-off-by: HuaCai Chen <chenhc@lemote.com>
---
 arch/mips/include/asm/mach-loongson32/regs-clk.h | 30 +++++++++-
 drivers/clk/loongson1/Makefile                   |  1 +
 drivers/clk/loongson1/clk-loongson1a.c           | 75 ++++++++++++++++++++++++
 3 files changed, 105 insertions(+), 1 deletion(-)
 create mode 100644 drivers/clk/loongson1/clk-loongson1a.c

diff --git a/arch/mips/include/asm/mach-loongson32/regs-clk.h b/arch/mips/include/asm/mach-loongson32/regs-clk.h
index e5e8f11..d8278a4 100644
--- a/arch/mips/include/asm/mach-loongson32/regs-clk.h
+++ b/arch/mips/include/asm/mach-loongson32/regs-clk.h
@@ -18,7 +18,35 @@
 #define LS1X_CLK_PLL_FREQ		LS1X_CLK_REG(0x0)
 #define LS1X_CLK_PLL_DIV		LS1X_CLK_REG(0x4)
 
-#if defined(CONFIG_LOONGSON1_LS1B)
+#if defined(CONFIG_LOONGSON1_LS1A)
+/* write only */
+#define CORE_PLL_CFG		0x1fe78030
+#define CPU_MUL			GENMASK(2, 0)
+#define CPU_CFG_EN		BIT(3)
+#define DDR_MUL			GENMASK(6, 4)
+#define DDR_CFG_EN		BIT(7)
+#define CPU_CFG_W_EN		BIT(11)
+#define DDR_CFG_W_EN		BIT(15)
+
+#define VGA_PLL_CFG		0x1fd00410
+#define VGA_M			GENMASK(7, 0)
+#define VGA_N			GENMASK(11, 8)
+#define VGA_OD			GENMASK(13, 12)
+#define VGA_FRAC		GENMASK(31, 14)
+
+#define LCD_PLL_CFG		0x1fd00410
+#define LCD_M			GENMASK(7, 0)
+#define LCD_N			GENMASK(11, 8)
+#define LCD_OD			GENMASK(13, 12)
+#define LCD_FRAC		GENMASK(31, 14)
+
+#define GPU_PLL_CFG		0x1fd00414
+#define GPU_M			GENMASK(7, 0)
+#define GPU_N			GENMASK(11, 8)
+#define GPU_OD			GENMASK(13, 12)
+#define GPU_FRAC		GENMASK(31, 14)
+
+#elif defined(CONFIG_LOONGSON1_LS1B)
 /* Clock PLL Divisor Register Bits */
 #define DIV_DC_EN			BIT(31)
 #define DIV_DC_RST			BIT(30)
diff --git a/drivers/clk/loongson1/Makefile b/drivers/clk/loongson1/Makefile
index b7f6a16..da7b2dd 100644
--- a/drivers/clk/loongson1/Makefile
+++ b/drivers/clk/loongson1/Makefile
@@ -1,3 +1,4 @@
 obj-y				+= clk.o
+obj-$(CONFIG_LOONGSON1_LS1A)	+= clk-loongson1a.o
 obj-$(CONFIG_LOONGSON1_LS1B)	+= clk-loongson1b.o
 obj-$(CONFIG_LOONGSON1_LS1C)	+= clk-loongson1c.o
diff --git a/drivers/clk/loongson1/clk-loongson1a.c b/drivers/clk/loongson1/clk-loongson1a.c
new file mode 100644
index 0000000..263a82c
--- /dev/null
+++ b/drivers/clk/loongson1/clk-loongson1a.c
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2012-2016 Binbin Zhou <zhoubb@lemote.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/err.h>
+
+#include <loongson1.h>
+#include "clk.h"
+
+#define OSC		(33 * 1000000)
+#define DIV_APB		2
+
+static DEFINE_SPINLOCK(_lock);
+
+static unsigned long ls1x_pll_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	/* Workaround, loongson-1A pll register is written only */
+	return OSC * 8;
+}
+
+static const struct clk_ops ls1x_pll_clk_ops = {
+	.recalc_rate = ls1x_pll_recalc_rate,
+};
+
+void __init ls1x_clk_init(void)
+{
+	struct clk_hw *hw;
+
+	hw = clk_hw_register_fixed_rate(NULL, "osc_clk", NULL, 0, OSC);
+	clk_hw_register_clkdev(hw, "osc_clk", NULL);
+
+	/* clock from 33 MHz OSC clk */
+	hw = clk_hw_register_pll(NULL, "pll_clk", "osc_clk",
+				&ls1x_pll_clk_ops, 0);
+	clk_hw_register_clkdev(hw, "pll_clk", NULL);
+
+	/* cpu clk */
+	hw = clk_hw_register_fixed_factor(NULL, "cpu_clk", "pll_clk",
+					0, 1, 1);
+	clk_hw_register_clkdev(hw, "cpu_clk", NULL);
+
+	/* dc clk */
+	hw = clk_hw_register_fixed_factor(NULL, "ddr_clk", "pll_clk",
+					0, 1, 1);
+	clk_hw_register_clkdev(hw, "ddr_clk", NULL);
+
+	/* ahb clk */
+	hw = clk_hw_register_fixed_factor(NULL, "ahb_clk", "pll_clk",
+					0, 1, 2);
+	clk_hw_register_clkdev(hw, "ahb_clk", NULL);
+	clk_hw_register_clkdev(hw, "ls1x-dma", NULL);
+	clk_hw_register_clkdev(hw, "stmmaceth", NULL);
+
+	/* clock derived from AHB clk */
+	/* APB clk is always half of the AHB clk */
+	hw = clk_hw_register_fixed_factor(NULL, "apb_clk", "ahb_clk",
+					0, 1, DIV_APB);
+	clk_hw_register_clkdev(hw, "apb_clk", NULL);
+	clk_hw_register_clkdev(hw, "ls1x-ac97", NULL);
+	clk_hw_register_clkdev(hw, "ls1x-i2c", NULL);
+	clk_hw_register_clkdev(hw, "ls1x-nand", NULL);
+	clk_hw_register_clkdev(hw, "ls1x-pwmtimer", NULL);
+	clk_hw_register_clkdev(hw, "ls1x-spi", NULL);
+	clk_hw_register_clkdev(hw, "ls1x-wdt", NULL);
+	clk_hw_register_clkdev(hw, "serial8250", NULL);
+}
-- 
2.9.3