From d68ff977b82954fed8e3f4bde8431517455c2003 Mon Sep 17 00:00:00 2001 From: Tero Kristo Date: Tue, 25 Sep 2012 19:33:41 +0300 Subject: [PATCH] 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: Tero Kristo Signed-off-by: Kevin Hilman --- arch/arm/mach-omap2/vc.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) diff --git a/arch/arm/mach-omap2/vc.c b/arch/arm/mach-omap2/vc.c index 07e2090..5d5f9e5 100644 --- a/arch/arm/mach-omap2/vc.c +++ b/arch/arm/mach-omap2/vc.c @@ -11,13 +11,19 @@ #include #include #include +#include +#include + +#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 */ @@ -365,6 +393,30 @@ static u32 omap4_calc_volt_ramp(struct voltagedomain *voltdm, u32 voltage_diff) } /** + * 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 * @off_mode: whether off-mode values are used @@ -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 */ -- 2.7.4