Thara Gopinath <th...@ti.com> writes:

> This patch introduces VP force update method of voltage scaling
> and enables it by default. The older method of vc bypass is now
> configuratble through a menu config option. VP force update is the
> hardware recommended method of voltage scaling.
>
> Signed-off-by: Thara Gopinath <th...@ti.com>

This should be a runtime option intead of a compile-time option.
Default should be HW recommended method, but board code should be able
to override.

Only did a quick glance at this, an some minor coding style issues below...

> ---
>  arch/arm/mach-omap2/voltage.c |  149 
> +++++++++++++++++++++++++++++++++++++++--
>  arch/arm/mach-omap2/voltage.h |    1 +
>  arch/arm/plat-omap/Kconfig    |   19 +++++
>  3 files changed, 162 insertions(+), 7 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/voltage.c b/arch/arm/mach-omap2/voltage.c
> index 49167c0..4f325af 100644
> --- a/arch/arm/mach-omap2/voltage.c
> +++ b/arch/arm/mach-omap2/voltage.c
> @@ -29,7 +29,8 @@
>  #include "prm-regbits-34xx.h"
>  #include "voltage.h"
>  
> -#define VP_IDLE_TIMEOUT 200
> +#define VP_IDLE_TIMEOUT      200
> +#define VP_TRANXDONE_TIMEOUT 300
>  
>  /*
>   * OMAP3 Voltage controller SR parameters. TODO: Pass this info as part of
> @@ -70,6 +71,7 @@ struct vp_reg_info {
>       u32 vp_vddmin;
>       u32 vp_vddmax;
>       u32 vp_timeout;
> +     u32 vp_tranxdone_status;
>  };
>  static struct vp_reg_info *vp_reg;
>  /*
> @@ -299,6 +301,8 @@ static void __init vp_reg_configure(int vp_id)
>                                       OMAP3430_VDDMIN_SHIFT);
>                       vp_reg[vp_id].vp_vddmax = (OMAP3_VP1_VLIMITTO_VDDMAX <<
>                                       OMAP3430_VDDMAX_SHIFT);
> +                     vp_reg[vp_id].vp_tranxdone_status =
> +                                     OMAP3430_VP1_TRANXDONE_ST;
>               } else if (vp_id == VP2) {
>                       /*
>                        * OMAP3430 has error gain varying btw higher and
> @@ -312,6 +316,8 @@ static void __init vp_reg_configure(int vp_id)
>                                       OMAP3430_VDDMIN_SHIFT);
>                       vp_reg[vp_id].vp_vddmax = (OMAP3_VP2_VLIMITTO_VDDMAX <<
>                                       OMAP3430_VDDMAX_SHIFT);
> +                     vp_reg[vp_id].vp_tranxdone_status =
> +                                     OMAP3430_VP2_TRANXDONE_ST;
>               } else {
>                       pr_warning("Voltage processor%d does not exisit\
>                                       in OMAP3 \n", vp_id);
> @@ -346,6 +352,131 @@ static void __init vp_reg_configure(int vp_id)
>       /* TODO Extend this for OMAP4 ?? Or need a separate file  */
>  }
>  
> +#ifdef CONFIG_OMAP_VOLT_VPFORCEUPDATE
> +/* VP force update method of voltage scaling */
> +static int vp_forceupdate_scale_voltage(u32 vdd, u8 target_vsel,
> +                             u8 current_vsel)
> +{
> +     u32 smps_steps = 0, smps_delay = 0;
> +     u32 vpconfig;
> +     int timeout = 0;
> +     int vp_id = vdd - 1;
> +
> +     if (!((vdd == VDD1_OPP) || (vdd == VDD2_OPP))) {
> +             pr_warning("Wrong vdd id passed to vp forceupdate\n");
> +             return false;
> +     }
> +
> +     smps_steps = abs(target_vsel - current_vsel);
> +
> +     /* OMAP3430 has errorgain varying btw higher and lower opp's */
> +     if (cpu_is_omap34xx()) {
> +             if (vdd == VDD1_OPP) {
> +                     u32 vc_cmdval0;
> +
> +                     vc_cmdval0 = voltage_read_reg(vc_reg.vc_cmdval0_reg);
> +                     vc_cmdval0 &= ~VC_CMD_ON_MASK;
> +                     vc_cmdval0 |= (target_vsel << VC_CMD_ON_SHIFT);
> +                     voltage_write_reg(vc_reg.vc_cmdval0_reg, vc_cmdval0);
> +                     vp_reg[vp_id].vp_errorgain = (((get_vdd1_opp() > 2) ?
> +                                     (OMAP3_VP_CONFIG_ERRORGAIN_HIGHOPP) :
> +                                     (OMAP3_VP_CONFIG_ERRORGAIN_LOWOPP)) <<
> +                                     OMAP3430_ERRORGAIN_SHIFT);
> +             } else if (vdd == VDD2_OPP) {
> +                     u32 vc_cmdval1;
> +
> +                     vc_cmdval1 = voltage_read_reg(vc_reg.vc_cmdval1_reg);
> +                     vc_cmdval1 &= ~VC_CMD_ON_MASK;
> +                     vc_cmdval1 |= (target_vsel << VC_CMD_ON_SHIFT);
> +                     voltage_write_reg(vc_reg.vc_cmdval1_reg, vc_cmdval1);
> +                     vp_reg[vp_id].vp_errorgain = (((get_vdd2_opp() > 2) ?
> +                                     (OMAP3_VP_CONFIG_ERRORGAIN_HIGHOPP) :
> +                                     (OMAP3_VP_CONFIG_ERRORGAIN_LOWOPP)) <<
> +                                     OMAP3430_ERRORGAIN_SHIFT);
> +             }
> +     }
> +
> +     /* Clear all pending TransactionDone interrupt/status. Typical latency
> +      * is <3us
> +      */
> +     while (timeout++ < VP_TRANXDONE_TIMEOUT) {
> +             voltage_write_reg(PRM_IRQSTATUS_REG,
> +                             vp_reg[vp_id].vp_tranxdone_status);
> +             if (!(voltage_read_reg(PRM_IRQSTATUS_REG) &
> +                             vp_reg[vp_id].vp_tranxdone_status))
> +                             break;
> +             udelay(1);
> +     }
> +
> +     if (timeout >= VP_TRANXDONE_TIMEOUT) {
> +             pr_warning("VP%d TRANXDONE timeout exceeded. Voltage change \
> +                             aborted", vdd);
> +             return false;
> +     }
> +
> +     /* Configure for VP-Force Update */
> +     vpconfig = voltage_read_reg(vp_reg[vp_id].vp_offs.vp_vpconfig_reg);
> +     vpconfig &= ~(VP_CONFIG_INITVDD | VP_FORCEUPDATE |
> +                     VP_INITVOLTAGE_MASK | VP_ERRORGAIN_MASK);
> +     vpconfig |= ((target_vsel << VP_INITVOLTAGE_SHIFT) |
> +                     vp_reg[vp_id].vp_errorgain);
> +     voltage_write_reg(vp_reg[vp_id].vp_offs.vp_vpconfig_reg, vpconfig);
> +
> +     /* Trigger initVDD value copy to voltage processor */
> +     vpconfig |= VP_CONFIG_INITVDD;
> +     voltage_write_reg(vp_reg[vp_id].vp_offs.vp_vpconfig_reg, vpconfig);
> +
> +     /* Force update of voltage */
> +     vpconfig |= VP_FORCEUPDATE;
> +     voltage_write_reg(vp_reg[vp_id].vp_offs.vp_vpconfig_reg, vpconfig);
> +
> +     timeout = 0;
> +     /* Wait for TransactionDone. Typical latency is <200us.
> +      * Depends on SMPSWAITTIMEMIN/MAX and voltage change
> +      */

multi-line comment style

> +     while ((timeout++ < VP_TRANXDONE_TIMEOUT) &&
> +                     (!(voltage_read_reg(PRM_IRQSTATUS_REG) &
> +                     vp_reg[vp_id].vp_tranxdone_status)))
> +             udelay(1);
> +
> +     if (timeout >= VP_TRANXDONE_TIMEOUT)
> +             pr_warning("VP%d TRANXDONE timeout exceeded. TRANXDONE never \
> +                     got set after the voltage update.Serious error!!!!\n",
> +                     vdd);
> +
> +     /* Wait for voltage to settle with SW wait-loop */
> +     smps_delay = ((smps_steps * 125) / 40) + 2;
> +     udelay(smps_delay);
> +
> +     /* Disable TransactionDone interrupt , clear all status, clear
> +      * control registers
> +      */

muti-line comment

> +     timeout = 0;
> +     while (timeout++ < VP_TRANXDONE_TIMEOUT) {
> +             voltage_write_reg(PRM_IRQSTATUS_REG,
> +                             vp_reg[vp_id].vp_tranxdone_status);
> +             if (!(voltage_read_reg(PRM_IRQSTATUS_REG) &
> +                             vp_reg[vp_id].vp_tranxdone_status))
> +                             break;
> +             udelay(1);
> +     }
> +     if (timeout >= VP_TRANXDONE_TIMEOUT)
> +             pr_warning("VP%d TRANXDONE timeout exceeded while trying to \
> +                     clear the TRANXDONE status\n", vdd);
> +
> +     vpconfig = voltage_read_reg(vp_reg[vp_id].vp_offs.vp_vpconfig_reg);
> +     /* Clear initVDD copy trigger bit */
> +     vpconfig &= ~VP_CONFIG_INITVDD;
> +     voltage_write_reg(vp_reg[vp_id].vp_offs.vp_vpconfig_reg, vpconfig);
> +     /* Clear force bit */
> +     vpconfig &= ~VP_FORCEUPDATE;
> +     voltage_write_reg(vp_reg[vp_id].vp_offs.vp_vpconfig_reg, vpconfig);
> +
> +     return true;
> +}
> +#endif
> +
> +#ifdef CONFIG_OMAP_VOLT_VCBYPASS
>  /**
>   * vc_bypass_scale_voltage - VC bypass method of voltage scaling
>   */
> @@ -437,7 +568,7 @@ static int vc_bypass_scale_voltage(u32 vdd, u8 
> target_vsel, u8 current_vsel)
>       udelay(smps_delay);
>       return true;
>  }
> -
> +#endif
>  
>  static void __init init_voltageprocessors(void)
>  {
> @@ -474,13 +605,16 @@ void omap_voltageprocessor_enable(int vp_id)
>       if (voltage_read_reg(vp_reg[vp_id - 1].vp_offs.vp_vpconfig_reg) &
>                               VP_CONFIG_VPENABLE)
>               return;
> +
> +#ifdef CONFIG_OMAP_VOLT_VCBYPASS
>       /*
>        * This latching is required only if VC bypass method is used for
>        * voltage scaling during dvfs.
>        */
>       vp_latch_vsel(vp_id - 1);
> -     vpconfig = voltage_read_reg(vp_reg[vp_id - 1].vp_offs.vp_vpconfig_reg);
> +#endif
>       /* Enable VP */
> +     vpconfig = voltage_read_reg(vp_reg[vp_id - 1].vp_offs.vp_vpconfig_reg);
>       voltage_write_reg(vp_reg[vp_id - 1].vp_offs.vp_vpconfig_reg,
>                               vpconfig | VP_CONFIG_VPENABLE);
>  }
> @@ -529,11 +663,12 @@ void omap_voltageprocessor_disable(int vp_id)
>   * for a particular voltage domain during dvfs or any other situation.
>   */
>  int omap_voltage_scale(int vdd, u8 target_vsel, u8 current_vsel)
> -{    /*
> -      * TODO add VP force update method of voltage scaling
> -      * and choose btw the two
> -      */
> +{
> +#ifdef CONFIG_OMAP_VOLT_VCBYPASS
>       return vc_bypass_scale_voltage(vdd, target_vsel, current_vsel);
> +#elif CONFIG_OMAP_VOLT_VPFORCEUPDATE
> +     return vp_forceupdate_scale_voltage(vdd, target_vsel, current_vsel);
> +#endif
>  }
>  
>  /**
> diff --git a/arch/arm/mach-omap2/voltage.h b/arch/arm/mach-omap2/voltage.h
> index c3203c9..615bde6 100644
> --- a/arch/arm/mach-omap2/voltage.h
> +++ b/arch/arm/mach-omap2/voltage.h
> @@ -17,6 +17,7 @@
>  extern int get_vdd1_opp(void);
>  extern int get_vdd2_opp(void);
>  
> +#define PRM_IRQSTATUS_REG    OMAP3430_PRM_IRQSTATUS_MPU
>  /* Generic VP definitions. Need to be redefined for OMAP4 */
>  #define VP_CONFIG_TIMEOUTEN  OMAP3430_TIMEOUTEN
>  #define VP_CONFIG_INITVDD    OMAP3430_INITVDD
> diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
> index 9d286e6..1a611a9 100644
> --- a/arch/arm/plat-omap/Kconfig
> +++ b/arch/arm/plat-omap/Kconfig
> @@ -92,6 +92,25 @@ config OMAP_SMARTREFLEX_TESTING
>  
>         WARNING: Enabling this option may cause your device to hang!
>  
> +choice
> +     prompt "Choose Voltage Scale method"
> +     depends on ARCH_OMAP3 && PM
> +     default OMAP_VOLT_VPFORCEUPDATE
> +
> +config OMAP_VOLT_VPFORCEUPDATE
> +     bool "Voltage scaling via VP force update method"
> +     help
> +      Say Y if you want to enable VP force update method
> +      of voltage scaling. This is the h/w recomended way
> +      of voltage scaling in OMAP3.
> +
> +config OMAP_VOLT_VCBYPASS
> +     bool "Voltage Scale via Voltage controller in bypass"
> +     help
> +      Say Y if you want to enable VC Bypass method of voltage scaling.
> +      Not the default recommended method.
> +endchoice
> +
>  config OMAP_RESET_CLOCKS
>       bool "Reset unused clocks during boot"
>       depends on ARCH_OMAP
> -- 
> 1.7.0.rc1.33.g07cf0f
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to