Commit 61ae48c3 authored by Alexander Shiyan's avatar Alexander Shiyan Committed by Arnd Bergmann
Browse files

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: default avatarAlexander Shiyan <shc_work@mail.ru>
parent 55d512e2

arch/arm/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -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.

arch/arm/mach-clps711x/common.c

+73 −16
Original line number Diff line number Diff line
@@ -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 <linux/kernel.h>

#include <linux/mm.h>

#include <linux/io.h>

#include <linux/init.h>

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/irq.h>

#include <linux/sched.h>

#include <linux/clk.h>

#include <linux/clkdev.h>

#include <linux/clk-provider.h>



#include <asm/sizes.h>

#include <mach/hardware.h>

#include <asm/irq.h>

#include <asm/leds.h>

#include <asm/pgtable.h>

#include <asm/page.h>

#include <asm/mach/map.h>

#include <asm/mach/time.h>

#include <asm/system_misc.h>



#include <mach/hardware.h>



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);

}

arch/arm/mach-clps711x/include/mach/timex.h

+1 −22
Original line number Diff line number Diff line 
/*

 *  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