Signed-off-by: Antony Pavlov <antonynpavlov@xxxxxxxxx> --- drivers/clk/Makefile | 1 + drivers/clk/clk-ath79.c | 137 +++++++++++++++++++++++++++++++++ include/dt-bindings/clock/ar933x-clk.h | 22 ++++++ 3 files changed, 160 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..1126840 --- /dev/null +++ b/drivers/clk/clk-ath79.c @@ -0,0 +1,137 @@ +/* + * Clock driver for Atheros AR933x SoCs. + * + * Copyright (C) 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 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/bitops.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/delay.h> +#include <linux/math64.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include "clk.h" + +#include <dt-bindings/clock/ar933x-clk.h> + +#include "asm/mach-ath79/ar71xx_regs.h" +#include "asm/mach-ath79/ath79.h" + +#define MHZ (1000 * 1000) + +static struct clk *ar933x_clks[AR933X_CLK_END]; + +static struct clk_onecell_data clk_data; + +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 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; + } + + ar933x_clks[AR933X_CLK_REF] = ath79_add_sys_clkdev("ref", ref_rate); + ar933x_clks[AR933X_CLK_CPU] = ath79_add_sys_clkdev("cpu", cpu_rate); + ar933x_clks[AR933X_CLK_DDR] = ath79_add_sys_clkdev("ddr", ddr_rate); + ar933x_clks[AR933X_CLK_AHB] = ath79_add_sys_clkdev("ahb", ahb_rate); + ar933x_clks[AR933X_CLK_WDT] = ath79_add_sys_clkdev("wdt", ahb_rate); + ar933x_clks[AR933X_CLK_UART] = ath79_add_sys_clkdev("uart", ref_rate); + + clk_data.clks = ar933x_clks; + clk_data.clk_num = AR933X_CLK_END; + + of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data); +} +CLK_OF_DECLARE(ar933x_clk, "qca,ar9330-pll", ar933x_clk_init); diff --git a/include/dt-bindings/clock/ar933x-clk.h b/include/dt-bindings/clock/ar933x-clk.h new file mode 100644 index 0000000..ed9e5d5 --- /dev/null +++ b/include/dt-bindings/clock/ar933x-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_AR933X_CLK_H +#define __DT_BINDINGS_AR933X_CLK_H + +#define AR933X_CLK_REF 0 +#define AR933X_CLK_CPU 1 +#define AR933X_CLK_DDR 2 +#define AR933X_CLK_AHB 3 +#define AR933X_CLK_WDT 4 +#define AR933X_CLK_UART 5 + +#define AR933X_CLK_END 6 + +#endif /* __DT_BINDINGS_AR933X_CLK_H */ -- 2.6.2