Commit d68ff977 authored by Tero Kristo's avatar Tero Kristo Committed by Kevin Hilman
Browse files

ARM: OMAP3+: voltage: use oscillator data to calculate setup times 



We now use the previously defined oscillator setup / shutdown times
to calculate the register values for CLKSETUP.

Signed-off-by: default avatarTero Kristo <t-kristo@ti.com>
Signed-off-by: default avatarKevin Hilman <khilman@ti.com>
parent 085b3025

arch/arm/mach-omap2/vc.c

+62 −0
Original line number Diff line number Diff line
@@ -11,13 +11,19 @@ 
#include <linux/delay.h>

#include <linux/init.h>

#include <linux/bug.h>

#include <linux/io.h>



#include <asm/div64.h>



#include "iomap.h"

#include "soc.h"

#include "voltage.h"

#include "vc.h"

#include "prm-regbits-34xx.h"

#include "prm-regbits-44xx.h"

#include "prm44xx.h"

#include "pm.h"

#include "scrm44xx.h"



/**

 * struct omap_vc_channel_cfg - describe the cfg_channel bitfield
@@ -204,6 +210,18 @@ int omap_vc_bypass_scale(struct voltagedomain *voltdm, 
	return 0;

}



/* Convert microsecond value to number of 32kHz clock cycles */

static inline u32 omap_usec_to_32k(u32 usec)

{

	return DIV_ROUND_UP_ULL(32768ULL * (u64)usec, 1000000ULL);

}



/* Set oscillator setup time for omap3 */

static void omap3_set_clksetup(u32 usec, struct voltagedomain *voltdm)

{

	voltdm->write(omap_usec_to_32k(usec), OMAP3_PRM_CLKSETUP_OFFSET);

}



/**

 * omap3_set_i2c_timings - sets i2c sleep timings for a channel

 * @voltdm: channel to configure
@@ -220,6 +238,12 @@ static void omap3_set_i2c_timings(struct voltagedomain *voltdm, bool off_mode) 
	unsigned long voltsetup1;

	u32 tgt_volt;



	/*

	 * Oscillator is shut down only if we are using sys_off_mode pad,

	 * thus we set a minimal setup time here

	 */

	omap3_set_clksetup(1, voltdm);



	if (off_mode)

		tgt_volt = voltdm->vc_param->off;

	else
@@ -260,6 +284,7 @@ static void omap3_set_off_timings(struct voltagedomain *voltdm) 
	unsigned long voltsetup2;

	unsigned long voltsetup2_old;

	u32 val;

	u32 tstart, tshut;



	/* check if sys_off_mode is used to control off-mode voltages */

	val = voltdm->read(OMAP3_PRM_VOLTCTRL_OFFSET);
@@ -269,6 +294,9 @@ static void omap3_set_off_timings(struct voltagedomain *voltdm) 
		return;

	}



	omap_pm_get_oscillator(&tstart, &tshut);

	omap3_set_clksetup(tstart, voltdm);



	clksetup = voltdm->read(OMAP3_PRM_CLKSETUP_OFFSET);



	/* voltsetup 2 in us */
@@ -364,6 +392,30 @@ static u32 omap4_calc_volt_ramp(struct voltagedomain *voltdm, u32 voltage_diff) 
		(cycles << OMAP4430_RAMP_UP_COUNT_SHIFT);

}



/**

 * omap4_usec_to_val_scrm - convert microsecond value to SCRM module bitfield

 * @usec: microseconds

 * @shift: number of bits to shift left

 * @mask: bitfield mask

 *

 * Converts microsecond value to OMAP4 SCRM bitfield. Bitfield is

 * shifted to requested position, and checked agains the mask value.

 * If larger, forced to the max value of the field (i.e. the mask itself.)

 * Returns the SCRM bitfield value.

 */

static u32 omap4_usec_to_val_scrm(u32 usec, int shift, u32 mask)

{

	u32 val;



	val = omap_usec_to_32k(usec) << shift;



	/* Check for overflow, if yes, force to max value */

	if (val > mask)

		val = mask;



	return val;

}



/**

 * omap4_set_timings - set voltage ramp timings for a channel

 * @voltdm: channel to configure
@@ -376,6 +428,7 @@ static void omap4_set_timings(struct voltagedomain *voltdm, bool off_mode) 
	u32 val;

	u32 ramp;

	int offset;

	u32 tstart, tshut;



	if (off_mode) {

		ramp = omap4_calc_volt_ramp(voltdm,
@@ -397,6 +450,15 @@ static void omap4_set_timings(struct voltagedomain *voltdm, bool off_mode) 
	val |= ramp << OMAP4430_RAMP_UP_COUNT_SHIFT;



	voltdm->write(val, offset);



	omap_pm_get_oscillator(&tstart, &tshut);



	val = omap4_usec_to_val_scrm(tstart, OMAP4_SETUPTIME_SHIFT,

		OMAP4_SETUPTIME_MASK);

	val |= omap4_usec_to_val_scrm(tshut, OMAP4_DOWNTIME_SHIFT,

		OMAP4_DOWNTIME_MASK);



	__raw_writel(val, OMAP4_SCRM_CLKSETUPTIME);

}



/* OMAP4 specific voltage init functions */