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							- /*
 
-  * OMAP Voltage Controller (VC) interface
 
-  *
 
-  * Copyright (C) 2011 Texas Instruments, Inc.
 
-  *
 
-  * This file is licensed under the terms of the GNU General Public
 
-  * License version 2. This program is licensed "as is" without any
 
-  * warranty of any kind, whether express or implied.
 
-  */
 
- #include <linux/kernel.h>
 
- #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"
 
- #include "control.h"
 
- /**
 
-  * struct omap_vc_channel_cfg - describe the cfg_channel bitfield
 
-  * @sa: bit for slave address
 
-  * @rav: bit for voltage configuration register
 
-  * @rac: bit for command configuration register
 
-  * @racen: enable bit for RAC
 
-  * @cmd: bit for command value set selection
 
-  *
 
-  * Channel configuration bits, common for OMAP3+
 
-  * OMAP3 register: PRM_VC_CH_CONF
 
-  * OMAP4 register: PRM_VC_CFG_CHANNEL
 
-  * OMAP5 register: PRM_VC_SMPS_<voltdm>_CONFIG
 
-  */
 
- struct omap_vc_channel_cfg {
 
- 	u8 sa;
 
- 	u8 rav;
 
- 	u8 rac;
 
- 	u8 racen;
 
- 	u8 cmd;
 
- };
 
- static struct omap_vc_channel_cfg vc_default_channel_cfg = {
 
- 	.sa    = BIT(0),
 
- 	.rav   = BIT(1),
 
- 	.rac   = BIT(2),
 
- 	.racen = BIT(3),
 
- 	.cmd   = BIT(4),
 
- };
 
- /*
 
-  * On OMAP3+, all VC channels have the above default bitfield
 
-  * configuration, except the OMAP4 MPU channel.  This appears
 
-  * to be a freak accident as every other VC channel has the
 
-  * default configuration, thus creating a mutant channel config.
 
-  */
 
- static struct omap_vc_channel_cfg vc_mutant_channel_cfg = {
 
- 	.sa    = BIT(0),
 
- 	.rav   = BIT(2),
 
- 	.rac   = BIT(3),
 
- 	.racen = BIT(4),
 
- 	.cmd   = BIT(1),
 
- };
 
- static struct omap_vc_channel_cfg *vc_cfg_bits;
 
- /* Default I2C trace length on pcb, 6.3cm. Used for capacitance calculations. */
 
- static u32 sr_i2c_pcb_length = 63;
 
- #define CFG_CHANNEL_MASK 0x1f
 
- /**
 
-  * omap_vc_config_channel - configure VC channel to PMIC mappings
 
-  * @voltdm: pointer to voltagdomain defining the desired VC channel
 
-  *
 
-  * Configures the VC channel to PMIC mappings for the following
 
-  * PMIC settings
 
-  * - i2c slave address (SA)
 
-  * - voltage configuration address (RAV)
 
-  * - command configuration address (RAC) and enable bit (RACEN)
 
-  * - command values for ON, ONLP, RET and OFF (CMD)
 
-  *
 
-  * This function currently only allows flexible configuration of the
 
-  * non-default channel.  Starting with OMAP4, there are more than 2
 
-  * channels, with one defined as the default (on OMAP4, it's MPU.)
 
-  * Only the non-default channel can be configured.
 
-  */
 
- static int omap_vc_config_channel(struct voltagedomain *voltdm)
 
- {
 
- 	struct omap_vc_channel *vc = voltdm->vc;
 
- 	/*
 
- 	 * For default channel, the only configurable bit is RACEN.
 
- 	 * All others must stay at zero (see function comment above.)
 
- 	 */
 
- 	if (vc->flags & OMAP_VC_CHANNEL_DEFAULT)
 
- 		vc->cfg_channel &= vc_cfg_bits->racen;
 
- 	voltdm->rmw(CFG_CHANNEL_MASK << vc->cfg_channel_sa_shift,
 
- 		    vc->cfg_channel << vc->cfg_channel_sa_shift,
 
- 		    vc->cfg_channel_reg);
 
- 	return 0;
 
- }
 
- /* Voltage scale and accessory APIs */
 
- int omap_vc_pre_scale(struct voltagedomain *voltdm,
 
- 		      unsigned long target_volt,
 
- 		      u8 *target_vsel, u8 *current_vsel)
 
- {
 
- 	struct omap_vc_channel *vc = voltdm->vc;
 
- 	u32 vc_cmdval;
 
- 	/* Check if sufficient pmic info is available for this vdd */
 
- 	if (!voltdm->pmic) {
 
- 		pr_err("%s: Insufficient pmic info to scale the vdd_%s\n",
 
- 			__func__, voltdm->name);
 
- 		return -EINVAL;
 
- 	}
 
- 	if (!voltdm->pmic->uv_to_vsel) {
 
- 		pr_err("%s: PMIC function to convert voltage in uV to vsel not registered. Hence unable to scale voltage for vdd_%s\n",
 
- 		       __func__, voltdm->name);
 
- 		return -ENODATA;
 
- 	}
 
- 	if (!voltdm->read || !voltdm->write) {
 
- 		pr_err("%s: No read/write API for accessing vdd_%s regs\n",
 
- 			__func__, voltdm->name);
 
- 		return -EINVAL;
 
- 	}
 
- 	*target_vsel = voltdm->pmic->uv_to_vsel(target_volt);
 
- 	*current_vsel = voltdm->pmic->uv_to_vsel(voltdm->nominal_volt);
 
- 	/* Setting the ON voltage to the new target voltage */
 
- 	vc_cmdval = voltdm->read(vc->cmdval_reg);
 
- 	vc_cmdval &= ~vc->common->cmd_on_mask;
 
- 	vc_cmdval |= (*target_vsel << vc->common->cmd_on_shift);
 
- 	voltdm->write(vc_cmdval, vc->cmdval_reg);
 
- 	voltdm->vc_param->on = target_volt;
 
- 	omap_vp_update_errorgain(voltdm, target_volt);
 
- 	return 0;
 
- }
 
- void omap_vc_post_scale(struct voltagedomain *voltdm,
 
- 			unsigned long target_volt,
 
- 			u8 target_vsel, u8 current_vsel)
 
- {
 
- 	u32 smps_steps = 0, smps_delay = 0;
 
- 	smps_steps = abs(target_vsel - current_vsel);
 
- 	/* SMPS slew rate / step size. 2us added as buffer. */
 
- 	smps_delay = ((smps_steps * voltdm->pmic->step_size) /
 
- 			voltdm->pmic->slew_rate) + 2;
 
- 	udelay(smps_delay);
 
- }
 
- /* vc_bypass_scale - VC bypass method of voltage scaling */
 
- int omap_vc_bypass_scale(struct voltagedomain *voltdm,
 
- 			 unsigned long target_volt)
 
- {
 
- 	struct omap_vc_channel *vc = voltdm->vc;
 
- 	u32 loop_cnt = 0, retries_cnt = 0;
 
- 	u32 vc_valid, vc_bypass_val_reg, vc_bypass_value;
 
- 	u8 target_vsel, current_vsel;
 
- 	int ret;
 
- 	ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, ¤t_vsel);
 
- 	if (ret)
 
- 		return ret;
 
- 	vc_valid = vc->common->valid;
 
- 	vc_bypass_val_reg = vc->common->bypass_val_reg;
 
- 	vc_bypass_value = (target_vsel << vc->common->data_shift) |
 
- 		(vc->volt_reg_addr << vc->common->regaddr_shift) |
 
- 		(vc->i2c_slave_addr << vc->common->slaveaddr_shift);
 
- 	voltdm->write(vc_bypass_value, vc_bypass_val_reg);
 
- 	voltdm->write(vc_bypass_value | vc_valid, vc_bypass_val_reg);
 
- 	vc_bypass_value = voltdm->read(vc_bypass_val_reg);
 
- 	/*
 
- 	 * Loop till the bypass command is acknowledged from the SMPS.
 
- 	 * NOTE: This is legacy code. The loop count and retry count needs
 
- 	 * to be revisited.
 
- 	 */
 
- 	while (!(vc_bypass_value & vc_valid)) {
 
- 		loop_cnt++;
 
- 		if (retries_cnt > 10) {
 
- 			pr_warning("%s: Retry count exceeded\n", __func__);
 
- 			return -ETIMEDOUT;
 
- 		}
 
- 		if (loop_cnt > 50) {
 
- 			retries_cnt++;
 
- 			loop_cnt = 0;
 
- 			udelay(10);
 
- 		}
 
- 		vc_bypass_value = voltdm->read(vc_bypass_val_reg);
 
- 	}
 
- 	omap_vc_post_scale(voltdm, target_volt, target_vsel, current_vsel);
 
- 	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
 
-  * @off_mode: select whether retention or off mode values used
 
-  *
 
-  * Calculates and sets up voltage controller to use I2C based
 
-  * voltage scaling for sleep modes. This can be used for either off mode
 
-  * or retention. Off mode has additionally an option to use sys_off_mode
 
-  * pad, which uses a global signal to program the whole power IC to
 
-  * off-mode.
 
-  */
 
- 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
 
- 		tgt_volt = voltdm->vc_param->ret;
 
- 	voltsetup1 = (voltdm->vc_param->on - tgt_volt) /
 
- 			voltdm->pmic->slew_rate;
 
- 	voltsetup1 = voltsetup1 * voltdm->sys_clk.rate / 8 / 1000000 + 1;
 
- 	voltdm->rmw(voltdm->vfsm->voltsetup_mask,
 
- 		voltsetup1 << __ffs(voltdm->vfsm->voltsetup_mask),
 
- 		voltdm->vfsm->voltsetup_reg);
 
- 	/*
 
- 	 * pmic is not controlling the voltage scaling during retention,
 
- 	 * thus set voltsetup2 to 0
 
- 	 */
 
- 	voltdm->write(0, OMAP3_PRM_VOLTSETUP2_OFFSET);
 
- }
 
- /**
 
-  * omap3_set_off_timings - sets off-mode timings for a channel
 
-  * @voltdm: channel to configure
 
-  *
 
-  * Calculates and sets up off-mode timings for a channel. Off-mode
 
-  * can use either I2C based voltage scaling, or alternatively
 
-  * sys_off_mode pad can be used to send a global command to power IC.
 
-  * This function first checks which mode is being used, and calls
 
-  * omap3_set_i2c_timings() if the system is using I2C control mode.
 
-  * sys_off_mode has the additional benefit that voltages can be
 
 
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