Nishanth Menon f2a0dfefec ARM: OMAP3+: PM: VP: use uV for max and min voltage limits
Every PMIC has it's own eccentricities, For example, one of the
PMIC has MSB set to 1 for a specific function - voltage enable!
using an hardcoded value specific for TWL when copied over to
such an implementation causes the system to crash as the MSB bit
was 0 and the voltage got disabled!.

Instead we use actual values and depend on the convertion routines
to abstract out the eccentricities of each PMIC.

With this, we can now move the voltages to a common location in
voltage.h as they are no longer dependent on PMICs and expect the
PMIC's conversion routines to set a cap if the voltage is out of
reach for the PMIC.

Reported-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Vishwanath BS <vishwanath.bs@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
2012-11-05 15:03:34 -08:00

282 lines
7.3 KiB
C

#include <linux/kernel.h>
#include <linux/init.h>
#include "common.h"
#include "voltage.h"
#include "vp.h"
#include "prm-regbits-34xx.h"
#include "prm-regbits-44xx.h"
#include "prm44xx.h"
static u32 _vp_set_init_voltage(struct voltagedomain *voltdm, u32 volt)
{
struct omap_vp_instance *vp = voltdm->vp;
u32 vpconfig;
char vsel;
vsel = voltdm->pmic->uv_to_vsel(volt);
vpconfig = voltdm->read(vp->vpconfig);
vpconfig &= ~(vp->common->vpconfig_initvoltage_mask |
vp->common->vpconfig_forceupdate |
vp->common->vpconfig_initvdd);
vpconfig |= vsel << __ffs(vp->common->vpconfig_initvoltage_mask);
voltdm->write(vpconfig, vp->vpconfig);
/* Trigger initVDD value copy to voltage processor */
voltdm->write((vpconfig | vp->common->vpconfig_initvdd),
vp->vpconfig);
/* Clear initVDD copy trigger bit */
voltdm->write(vpconfig, vp->vpconfig);
return vpconfig;
}
/* Generic voltage init functions */
void __init omap_vp_init(struct voltagedomain *voltdm)
{
struct omap_vp_instance *vp = voltdm->vp;
u32 val, sys_clk_rate, timeout, waittime;
u32 vddmin, vddmax, vstepmin, vstepmax;
if (!voltdm->pmic || !voltdm->pmic->uv_to_vsel) {
pr_err("%s: No PMIC info for vdd_%s\n", __func__, voltdm->name);
return;
}
if (!voltdm->read || !voltdm->write) {
pr_err("%s: No read/write API for accessing vdd_%s regs\n",
__func__, voltdm->name);
return;
}
vp->enabled = false;
/* Divide to avoid overflow */
sys_clk_rate = voltdm->sys_clk.rate / 1000;
timeout = (sys_clk_rate * voltdm->pmic->vp_timeout_us) / 1000;
vddmin = voltdm->pmic->uv_to_vsel(voltdm->pmic->vp_vddmin);
vddmax = voltdm->pmic->uv_to_vsel(voltdm->pmic->vp_vddmax);
waittime = DIV_ROUND_UP(voltdm->pmic->step_size * sys_clk_rate,
1000 * voltdm->pmic->slew_rate);
vstepmin = voltdm->pmic->vp_vstepmin;
vstepmax = voltdm->pmic->vp_vstepmax;
/*
* VP_CONFIG: error gain is not set here, it will be updated
* on each scale, based on OPP.
*/
val = (voltdm->pmic->vp_erroroffset <<
__ffs(voltdm->vp->common->vpconfig_erroroffset_mask)) |
vp->common->vpconfig_timeouten;
voltdm->write(val, vp->vpconfig);
/* VSTEPMIN */
val = (waittime << vp->common->vstepmin_smpswaittimemin_shift) |
(vstepmin << vp->common->vstepmin_stepmin_shift);
voltdm->write(val, vp->vstepmin);
/* VSTEPMAX */
val = (vstepmax << vp->common->vstepmax_stepmax_shift) |
(waittime << vp->common->vstepmax_smpswaittimemax_shift);
voltdm->write(val, vp->vstepmax);
/* VLIMITTO */
val = (vddmax << vp->common->vlimitto_vddmax_shift) |
(vddmin << vp->common->vlimitto_vddmin_shift) |
(timeout << vp->common->vlimitto_timeout_shift);
voltdm->write(val, vp->vlimitto);
}
int omap_vp_update_errorgain(struct voltagedomain *voltdm,
unsigned long target_volt)
{
struct omap_volt_data *volt_data;
if (!voltdm->vp)
return -EINVAL;
/* Get volt_data corresponding to target_volt */
volt_data = omap_voltage_get_voltdata(voltdm, target_volt);
if (IS_ERR(volt_data))
return -EINVAL;
/* Setting vp errorgain based on the voltage */
voltdm->rmw(voltdm->vp->common->vpconfig_errorgain_mask,
volt_data->vp_errgain <<
__ffs(voltdm->vp->common->vpconfig_errorgain_mask),
voltdm->vp->vpconfig);
return 0;
}
/* VP force update method of voltage scaling */
int omap_vp_forceupdate_scale(struct voltagedomain *voltdm,
unsigned long target_volt)
{
struct omap_vp_instance *vp = voltdm->vp;
u32 vpconfig;
u8 target_vsel, current_vsel;
int ret, timeout = 0;
ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, &current_vsel);
if (ret)
return ret;
/*
* Clear all pending TransactionDone interrupt/status. Typical latency
* is <3us
*/
while (timeout++ < VP_TRANXDONE_TIMEOUT) {
vp->common->ops->clear_txdone(vp->id);
if (!vp->common->ops->check_txdone(vp->id))
break;
udelay(1);
}
if (timeout >= VP_TRANXDONE_TIMEOUT) {
pr_warn("%s: vdd_%s TRANXDONE timeout exceeded. Voltage change aborted",
__func__, voltdm->name);
return -ETIMEDOUT;
}
vpconfig = _vp_set_init_voltage(voltdm, target_volt);
/* Force update of voltage */
voltdm->write(vpconfig | vp->common->vpconfig_forceupdate,
voltdm->vp->vpconfig);
/*
* Wait for TransactionDone. Typical latency is <200us.
* Depends on SMPSWAITTIMEMIN/MAX and voltage change
*/
timeout = 0;
omap_test_timeout(vp->common->ops->check_txdone(vp->id),
VP_TRANXDONE_TIMEOUT, timeout);
if (timeout >= VP_TRANXDONE_TIMEOUT)
pr_err("%s: vdd_%s TRANXDONE timeout exceeded. TRANXDONE never got set after the voltage update\n",
__func__, voltdm->name);
omap_vc_post_scale(voltdm, target_volt, target_vsel, current_vsel);
/*
* Disable TransactionDone interrupt , clear all status, clear
* control registers
*/
timeout = 0;
while (timeout++ < VP_TRANXDONE_TIMEOUT) {
vp->common->ops->clear_txdone(vp->id);
if (!vp->common->ops->check_txdone(vp->id))
break;
udelay(1);
}
if (timeout >= VP_TRANXDONE_TIMEOUT)
pr_warn("%s: vdd_%s TRANXDONE timeout exceeded while trying to clear the TRANXDONE status\n",
__func__, voltdm->name);
/* Clear force bit */
voltdm->write(vpconfig, vp->vpconfig);
return 0;
}
/**
* omap_vp_enable() - API to enable a particular VP
* @voltdm: pointer to the VDD whose VP is to be enabled.
*
* This API enables a particular voltage processor. Needed by the smartreflex
* class drivers.
*/
void omap_vp_enable(struct voltagedomain *voltdm)
{
struct omap_vp_instance *vp;
u32 vpconfig, volt;
if (!voltdm || IS_ERR(voltdm)) {
pr_warning("%s: VDD specified does not exist!\n", __func__);
return;
}
vp = voltdm->vp;
if (!voltdm->read || !voltdm->write) {
pr_err("%s: No read/write API for accessing vdd_%s regs\n",
__func__, voltdm->name);
return;
}
/* If VP is already enabled, do nothing. Return */
if (vp->enabled)
return;
volt = voltdm_get_voltage(voltdm);
if (!volt) {
pr_warning("%s: unable to find current voltage for %s\n",
__func__, voltdm->name);
return;
}
vpconfig = _vp_set_init_voltage(voltdm, volt);
/* Enable VP */
vpconfig |= vp->common->vpconfig_vpenable;
voltdm->write(vpconfig, vp->vpconfig);
vp->enabled = true;
}
/**
* omap_vp_disable() - API to disable a particular VP
* @voltdm: pointer to the VDD whose VP is to be disabled.
*
* This API disables a particular voltage processor. Needed by the smartreflex
* class drivers.
*/
void omap_vp_disable(struct voltagedomain *voltdm)
{
struct omap_vp_instance *vp;
u32 vpconfig;
int timeout;
if (!voltdm || IS_ERR(voltdm)) {
pr_warning("%s: VDD specified does not exist!\n", __func__);
return;
}
vp = voltdm->vp;
if (!voltdm->read || !voltdm->write) {
pr_err("%s: No read/write API for accessing vdd_%s regs\n",
__func__, voltdm->name);
return;
}
/* If VP is already disabled, do nothing. Return */
if (!vp->enabled) {
pr_warn("%s: Trying to disable VP for vdd_%s when it is already disabled\n",
__func__, voltdm->name);
return;
}
/* Disable VP */
vpconfig = voltdm->read(vp->vpconfig);
vpconfig &= ~vp->common->vpconfig_vpenable;
voltdm->write(vpconfig, vp->vpconfig);
/*
* Wait for VP idle Typical latency is <2us. Maximum latency is ~100us
*/
omap_test_timeout((voltdm->read(vp->vstatus)),
VP_IDLE_TIMEOUT, timeout);
if (timeout >= VP_IDLE_TIMEOUT)
pr_warning("%s: vdd_%s idle timedout\n",
__func__, voltdm->name);
vp->enabled = false;
return;
}