From 61ae48c3cb6bcffd1c7e18164c3d103eb62f06aa Mon Sep 17 00:00:00 2001 From: Alexander Shiyan Date: Tue, 21 Aug 2012 20:59:35 +0400 Subject: [PATCH] ARM: clps711x: Added simple clock framework Modern CPUs from CLPS711X-line can operate at frequencies other than 73 MHz. This patch adds simple clock framework for handling all possible CPU rates. Signed-off-by: Alexander Shiyan --- arch/arm/Kconfig | 2 + arch/arm/mach-clps711x/common.c | 89 +++++++++++++++++---- arch/arm/mach-clps711x/include/mach/timex.h | 23 +----- 3 files changed, 76 insertions(+), 38 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 2f88d8d97701..0e7672179b40 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -384,6 +384,8 @@ config ARCH_CLPS711X bool "Cirrus Logic CLPS711x/EP721x/EP731x-based" select CPU_ARM720T select ARCH_USES_GETTIMEOFFSET + select COMMON_CLK + select CLKDEV_LOOKUP select NEED_MACH_MEMORY_H help Support for Cirrus Logic 711x/721x/731x based boards. diff --git a/arch/arm/mach-clps711x/common.c b/arch/arm/mach-clps711x/common.c index f15293bd7974..509243d89a32 100644 --- a/arch/arm/mach-clps711x/common.c +++ b/arch/arm/mach-clps711x/common.c @@ -19,24 +19,25 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ -#include -#include +#include #include #include -#include #include -#include +#include +#include +#include #include -#include -#include -#include -#include -#include #include #include #include +#include + +static struct clk *clk_pll, *clk_bus, *clk_uart, *clk_timerl, *clk_timerh, + *clk_tint, *clk_spi; +static unsigned long latch; + /* * This maps the generic CLPS711x registers */ @@ -166,8 +167,8 @@ void __init clps711x_init_irq(void) static unsigned long clps711x_gettimeoffset(void) { unsigned long hwticks; - hwticks = LATCH - (clps_readl(TC2D) & 0xffff); /* since last underflow */ - return (hwticks * (tick_nsec / 1000)) / LATCH; + hwticks = latch - (clps_readl(TC2D) & 0xffff); + return (hwticks * (tick_nsec / 1000)) / latch; } /* @@ -185,15 +186,71 @@ static struct irqaction clps711x_timer_irq = { .handler = p720t_timer_interrupt, }; +static void add_fixed_clk(struct clk *clk, const char *name, int rate) +{ + clk = clk_register_fixed_rate(NULL, name, NULL, CLK_IS_ROOT, rate); + clk_register_clkdev(clk, name, NULL); +} + static void __init clps711x_timer_init(void) { - unsigned int syscon; + int osc, ext, pll, cpu, bus, timl, timh, uart, spi; + u32 tmp; + + osc = 3686400; + ext = 13000000; + + tmp = clps_readl(PLLR) >> 24; + if (tmp) + pll = (osc * tmp) / 2; + else + pll = 73728000; /* Default value */ + + tmp = clps_readl(SYSFLG2); + if (tmp & SYSFLG2_CKMODE) { + cpu = ext; + bus = cpu; + spi = 135400; + } else { + cpu = pll; + if (cpu >= 36864000) + bus = cpu / 2; + else + bus = 36864000 / 2; + spi = cpu / 576; + } + + uart = bus / 10; + + if (tmp & SYSFLG2_CKMODE) { + tmp = clps_readl(SYSCON2); + if (tmp & SYSCON2_OSTB) + timh = ext / 26; + else + timh = 541440; + } else + timh = cpu / 144; + + timl = timh / 256; + + /* All clocks are fixed */ + add_fixed_clk(clk_pll, "pll", pll); + add_fixed_clk(clk_bus, "bus", bus); + add_fixed_clk(clk_uart, "uart", uart); + add_fixed_clk(clk_timerl, "timer_lf", timl); + add_fixed_clk(clk_timerh, "timer_hf", timh); + add_fixed_clk(clk_tint, "tint", 64); + add_fixed_clk(clk_spi, "spi", spi); + + pr_info("CPU frequency set at %i Hz.\n", cpu); + + latch = (timh + HZ / 2) / HZ; - syscon = clps_readl(SYSCON1); - syscon |= SYSCON1_TC2S | SYSCON1_TC2M; - clps_writel(syscon, SYSCON1); + tmp = clps_readl(SYSCON1); + tmp |= SYSCON1_TC2S | SYSCON1_TC2M; + clps_writel(tmp, SYSCON1); - clps_writel(LATCH-1, TC2D); /* 512kHz / 100Hz - 1 */ + clps_writel(latch - 1, TC2D); setup_irq(IRQ_TC2OI, &clps711x_timer_irq); } diff --git a/arch/arm/mach-clps711x/include/mach/timex.h b/arch/arm/mach-clps711x/include/mach/timex.h index ac8823ccff93..de6fd192d1c3 100644 --- a/arch/arm/mach-clps711x/include/mach/timex.h +++ b/arch/arm/mach-clps711x/include/mach/timex.h @@ -1,23 +1,2 @@ -/* - * arch/arm/mach-clps711x/include/mach/timex.h - * - * Prospector 720T architecture timex specifications - * - * Copyright (C) 2000 Deep Blue Solutions Ltd. - * - * 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. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - +/* Bogus value */ #define CLOCK_TICK_RATE 512000 -- 2.39.5