diff options
Diffstat (limited to 'arch/arm/mach-omap2/vp.c')
-rw-r--r-- | arch/arm/mach-omap2/vp.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/vp.c b/arch/arm/mach-omap2/vp.c new file mode 100644 index 000000000000..66bd700a2b98 --- /dev/null +++ b/arch/arm/mach-omap2/vp.c @@ -0,0 +1,278 @@ +#include <linux/kernel.h> +#include <linux/init.h> + +#include <plat/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->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->vp_vddmin; + vddmax = voltdm->pmic->vp_vddmax; + + waittime = ((voltdm->pmic->step_size / voltdm->pmic->slew_rate) * + sys_clk_rate) / 1000; + 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, ¤t_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_warning("%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_warning("%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_warning("%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; +} |