TODO: get pll registers base address from devicetree node
Signed-off-by: Antony Pavlov <antonynpavlov@xxxxxxxxx>
Cc: Alban Bedel <albeu@xxxxxxx>
Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: linux-clk@xxxxxxxxxxxxxxx
Cc: linux-mips@xxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
---
drivers/clk/Makefile | 1 +
drivers/clk/clk-ath79.c | 193 ++++++++++++++++++++++++++++++++++
include/dt-bindings/clock/ath79-clk.h | 22 ++++
3 files changed, 216 insertions(+)
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 820714c..5101763 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -18,6 +18,7 @@ endif
# hardware specific clock types
# please keep this section sorted lexicographically by file/directory path name
obj-$(CONFIG_MACH_ASM9260) += clk-asm9260.o
+obj-$(CONFIG_ATH79) += clk-ath79.o
obj-$(CONFIG_COMMON_CLK_AXI_CLKGEN) += clk-axi-clkgen.o
obj-$(CONFIG_ARCH_AXXIA) += clk-axm5516.o
obj-$(CONFIG_COMMON_CLK_CDCE706) += clk-cdce706.o
diff --git a/drivers/clk/clk-ath79.c b/drivers/clk/clk-ath79.c
new file mode 100644
index 0000000..75338a7
--- /dev/null
+++ b/drivers/clk/clk-ath79.c
@@ -0,0 +1,193 @@
+/*
+ * Clock driver for Atheros AR724X/AR913X/AR933X SoCs
+ *
+ * Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@xxxxxxxxxxx>
+ * Copyright (C) 2011 Gabor Juhos <juhosg@xxxxxxxxxxx>
+ * Copyright (C) 2015 Alban Bedel <albeu@xxxxxxx>
+ * Copyright (C) 2016 Antony Pavlov <antonynpavlov@xxxxxxxxx>
+ *
+ * Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include "clk.h"
+
+#include <dt-bindings/clock/ath79-clk.h>
+
+#include "asm/mach-ath79/ar71xx_regs.h"
+#include "asm/mach-ath79/ath79.h"
+
+#define MHZ (1000 * 1000)
+
+#define AR724X_BASE_FREQ (40 * MHZ)
+
+static struct clk *ath79_clks[ATH79_CLK_END];
+
+static struct clk_onecell_data clk_data = {
+ .clks = ath79_clks,
+ .clk_num = ARRAY_SIZE(ath79_clks),
+};
+
+static struct clk *__init ath79_add_sys_clkdev(
+ const char *id, unsigned long rate)
+{
+ struct clk *clk;
+ int err;
+
+ clk = clk_register_fixed_rate(NULL, id, NULL, CLK_IS_ROOT, rate);
+ if (!clk)
+ panic("failed to allocate %s clock structure", id);
+
+ err = clk_register_clkdev(clk, id, NULL);
+ if (err)
+ panic("unable to register %s clock device", id);
+
+ return clk;
+}
+
+static void __init ar724x_clk_init(struct device_node *np)
+{
+ struct clk *ref_clk;
+ unsigned long of_ref_rate;
+ unsigned long ref_rate;
+ unsigned long cpu_rate;
+ unsigned long ddr_rate;
+ unsigned long ahb_rate;
+ u32 pll;
+ u32 freq;
+ u32 div;
+
+ ref_clk = of_clk_get(np, 0);
+ if (IS_ERR(ref_clk)) {
+ pr_err("%s: of_clk_get failed\n", np->full_name);
+ return;
+ }
+
+ of_ref_rate = clk_get_rate(ref_clk);
+
+ ref_rate = AR724X_BASE_FREQ;
+
+ if (of_ref_rate != ref_rate) {
+ pr_err("ref_rate != of_ref_rate\n");
+ ref_rate = of_ref_rate;
+ }
+
+ pll = ath79_pll_rr(AR724X_PLL_REG_CPU_CONFIG);
+
+ div = ((pll >> AR724X_PLL_FB_SHIFT) & AR724X_PLL_FB_MASK);
+ freq = div * ref_rate;
+
+ div = ((pll >> AR724X_PLL_REF_DIV_SHIFT) & AR724X_PLL_REF_DIV_MASK) * 2;
+ freq /= div;
+
+ cpu_rate = freq;
+
+ div = ((pll >> AR724X_DDR_DIV_SHIFT) & AR724X_DDR_DIV_MASK) + 1;
+ ddr_rate = freq / div;
+
+ div = (((pll >> AR724X_AHB_DIV_SHIFT) & AR724X_AHB_DIV_MASK) + 1) * 2;
+ ahb_rate = cpu_rate / div;
+
+ ath79_clks[ATH79_CLK_REF] = ath79_add_sys_clkdev("ref", ref_rate);
+ ath79_clks[ATH79_CLK_CPU] = ath79_add_sys_clkdev("cpu", cpu_rate);
+ ath79_clks[ATH79_CLK_DDR] = ath79_add_sys_clkdev("ddr", ddr_rate);
+ ath79_clks[ATH79_CLK_AHB] = ath79_add_sys_clkdev("ahb", ahb_rate);
+ ath79_clks[ATH79_CLK_WDT] = ath79_add_sys_clkdev("wdt", ahb_rate);
+ ath79_clks[ATH79_CLK_UART] = ath79_add_sys_clkdev("uart", ahb_rate);
+
+ of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+
+static void __init ar933x_clk_init(struct device_node *np)
+{
+ struct clk *ref_clk;
+ unsigned long of_ref_rate;
+ unsigned long ref_rate;
+ unsigned long cpu_rate;
+ unsigned long ddr_rate;
+ unsigned long ahb_rate;
+ u32 clock_ctrl;
+ u32 cpu_config;
+ u32 freq;
+ u32 t;
+
+ ref_clk = of_clk_get(np, 0);
+ if (IS_ERR(ref_clk)) {
+ pr_err("%s: of_clk_get failed\n", np->full_name);
+ return;
+ }
+
+ of_ref_rate = clk_get_rate(ref_clk);
+
+ t = ath79_reset_rr(AR933X_RESET_REG_BOOTSTRAP);
+ if (t & AR933X_BOOTSTRAP_REF_CLK_40)
+ ref_rate = 40 * MHZ;
+ else
+ ref_rate = 25 * MHZ;
+
+ if (ref_rate != of_ref_rate) {
+ pr_err("ref_rate != of_ref_rate\n");
+ ref_rate = of_ref_rate;
+ }
+
+ clock_ctrl = ath79_pll_rr(AR933X_PLL_CLOCK_CTRL_REG);
+ if (clock_ctrl & AR933X_PLL_CLOCK_CTRL_BYPASS) {
+ cpu_rate = ref_rate;
+ ahb_rate = ref_rate;
+ ddr_rate = ref_rate;
+ } else {
+ cpu_config = ath79_pll_rr(AR933X_PLL_CPU_CONFIG_REG);
+
+ t = (cpu_config >> AR933X_PLL_CPU_CONFIG_REFDIV_SHIFT) &
+ AR933X_PLL_CPU_CONFIG_REFDIV_MASK;
+ freq = ref_rate / t;
+
+ t = (cpu_config >> AR933X_PLL_CPU_CONFIG_NINT_SHIFT) &
+ AR933X_PLL_CPU_CONFIG_NINT_MASK;
+ freq *= t;
+
+ t = (cpu_config >> AR933X_PLL_CPU_CONFIG_OUTDIV_SHIFT) &
+ AR933X_PLL_CPU_CONFIG_OUTDIV_MASK;
+ if (t == 0)
+ t = 1;
+
+ freq >>= t;
+
+ t = ((clock_ctrl >> AR933X_PLL_CLOCK_CTRL_CPU_DIV_SHIFT) &
+ AR933X_PLL_CLOCK_CTRL_CPU_DIV_MASK) + 1;
+ cpu_rate = freq / t;
+
+ t = ((clock_ctrl >> AR933X_PLL_CLOCK_CTRL_DDR_DIV_SHIFT) &
+ AR933X_PLL_CLOCK_CTRL_DDR_DIV_MASK) + 1;
+ ddr_rate = freq / t;
+
+ t = ((clock_ctrl >> AR933X_PLL_CLOCK_CTRL_AHB_DIV_SHIFT) &
+ AR933X_PLL_CLOCK_CTRL_AHB_DIV_MASK) + 1;
+ ahb_rate = freq / t;
+ }
+
+ ath79_clks[ATH79_CLK_REF] = ath79_add_sys_clkdev("ref", ref_rate);
+ ath79_clks[ATH79_CLK_CPU] = ath79_add_sys_clkdev("cpu", cpu_rate);
+ ath79_clks[ATH79_CLK_DDR] = ath79_add_sys_clkdev("ddr", ddr_rate);
+ ath79_clks[ATH79_CLK_AHB] = ath79_add_sys_clkdev("ahb", ahb_rate);
+ ath79_clks[ATH79_CLK_WDT] = ath79_add_sys_clkdev("wdt", ahb_rate);
+ ath79_clks[ATH79_CLK_UART] = ath79_add_sys_clkdev("uart", ref_rate);
+
+ of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+CLK_OF_DECLARE(ar9130_clk, "qca,ar9130-pll", ar724x_clk_init);
+CLK_OF_DECLARE(ar933x_clk, "qca,ar9330-pll", ar933x_clk_init);
diff --git a/include/dt-bindings/clock/ath79-clk.h b/include/dt-bindings/clock/ath79-clk.h
new file mode 100644
index 0000000..1c6fb04
--- /dev/null
+++ b/include/dt-bindings/clock/ath79-clk.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2014, 2016 Antony Pavlov <antonynpavlov@xxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#ifndef __DT_BINDINGS_ATH79_CLK_H
+#define __DT_BINDINGS_ATH79_CLK_H
+
+#define ATH79_CLK_REF 0
+#define ATH79_CLK_CPU 1
+#define ATH79_CLK_DDR 2
+#define ATH79_CLK_AHB 3
+#define ATH79_CLK_WDT 4
+#define ATH79_CLK_UART 5
+
+#define ATH79_CLK_END 6
+
+#endif /* __DT_BINDINGS_ATH79_CLK_H */
--
2.6.2
