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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/arm/mach-omap2/vc.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/mach-omap2/vc.c')
-rw-r--r-- | arch/arm/mach-omap2/vc.c | 894 |
1 files changed, 894 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/vc.c b/arch/arm/mach-omap2/vc.c new file mode 100644 index 000000000..ea02d4040 --- /dev/null +++ b/arch/arm/mach-omap2/vc.c @@ -0,0 +1,894 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * OMAP Voltage Controller (VC) interface + * + * Copyright (C) 2011 Texas Instruments, Inc. + */ +#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" + +#define OMAP4430_VDD_IVA_I2C_DISABLE BIT(14) +#define OMAP4430_VDD_MPU_I2C_DISABLE BIT(13) +#define OMAP4430_VDD_CORE_I2C_DISABLE BIT(12) +#define OMAP4430_VDD_IVA_PRESENCE BIT(9) +#define OMAP4430_VDD_MPU_PRESENCE BIT(8) +#define OMAP4430_AUTO_CTRL_VDD_IVA(x) ((x) << 4) +#define OMAP4430_AUTO_CTRL_VDD_MPU(x) ((x) << 2) +#define OMAP4430_AUTO_CTRL_VDD_CORE(x) ((x) << 0) +#define OMAP4430_AUTO_CTRL_VDD_RET 2 + +#define OMAP4430_VDD_I2C_DISABLE_MASK \ + (OMAP4430_VDD_IVA_I2C_DISABLE | \ + OMAP4430_VDD_MPU_I2C_DISABLE | \ + OMAP4430_VDD_CORE_I2C_DISABLE) + +#define OMAP4_VDD_DEFAULT_VAL \ + (OMAP4430_VDD_I2C_DISABLE_MASK | \ + OMAP4430_VDD_IVA_PRESENCE | OMAP4430_VDD_MPU_PRESENCE | \ + OMAP4430_AUTO_CTRL_VDD_IVA(OMAP4430_AUTO_CTRL_VDD_RET) | \ + OMAP4430_AUTO_CTRL_VDD_MPU(OMAP4430_AUTO_CTRL_VDD_RET) | \ + OMAP4430_AUTO_CTRL_VDD_CORE(OMAP4430_AUTO_CTRL_VDD_RET)) + +#define OMAP4_VDD_RET_VAL \ + (OMAP4_VDD_DEFAULT_VAL & ~OMAP4430_VDD_I2C_DISABLE_MASK) + +/** + * 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_warn("%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); +} + +struct omap3_vc_timings { + u32 voltsetup1; + u32 voltsetup2; +}; + +struct omap3_vc { + struct voltagedomain *vd; + u32 voltctrl; + u32 voltsetup1; + u32 voltsetup2; + struct omap3_vc_timings timings[2]; +}; +static struct omap3_vc vc; + +void omap3_vc_set_pmic_signaling(int core_next_state) +{ + struct voltagedomain *vd = vc.vd; + struct omap3_vc_timings *c = vc.timings; + u32 voltctrl, voltsetup1, voltsetup2; + + voltctrl = vc.voltctrl; + voltsetup1 = vc.voltsetup1; + voltsetup2 = vc.voltsetup2; + + switch (core_next_state) { + case PWRDM_POWER_OFF: + voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_RET | + OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP); + voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_OFF; + if (voltctrl & OMAP3430_PRM_VOLTCTRL_SEL_OFF) + voltsetup2 = c->voltsetup2; + else + voltsetup1 = c->voltsetup1; + break; + case PWRDM_POWER_RET: + default: + c++; + voltctrl &= ~(OMAP3430_PRM_VOLTCTRL_AUTO_OFF | + OMAP3430_PRM_VOLTCTRL_AUTO_SLEEP); + voltctrl |= OMAP3430_PRM_VOLTCTRL_AUTO_RET; + voltsetup1 = c->voltsetup1; + break; + } + + if (voltctrl != vc.voltctrl) { + vd->write(voltctrl, OMAP3_PRM_VOLTCTRL_OFFSET); + vc.voltctrl = voltctrl; + } + if (voltsetup1 != vc.voltsetup1) { + vd->write(c->voltsetup1, + OMAP3_PRM_VOLTSETUP1_OFFSET); + vc.voltsetup1 = voltsetup1; + } + if (voltsetup2 != vc.voltsetup2) { + vd->write(c->voltsetup2, + OMAP3_PRM_VOLTSETUP2_OFFSET); + vc.voltsetup2 = voltsetup2; + } +} + +void omap4_vc_set_pmic_signaling(int core_next_state) +{ + struct voltagedomain *vd = vc.vd; + u32 val; + + if (!vd) + return; + + switch (core_next_state) { + case PWRDM_POWER_RET: + val = OMAP4_VDD_RET_VAL; + break; + default: + val = OMAP4_VDD_DEFAULT_VAL; + break; + } + + vd->write(val, OMAP4_PRM_VOLTCTRL_OFFSET); +} + +/* + * Configure signal polarity for sys_clkreq and sys_off_mode pins + * as the default values are wrong and can cause the system to hang + * if any twl4030 scripts are loaded. + */ +static void __init omap3_vc_init_pmic_signaling(struct voltagedomain *voltdm) +{ + u32 val; + + if (vc.vd) + return; + + vc.vd = voltdm; + + val = voltdm->read(OMAP3_PRM_POLCTRL_OFFSET); + if (!(val & OMAP3430_PRM_POLCTRL_CLKREQ_POL) || + (val & OMAP3430_PRM_POLCTRL_OFFMODE_POL)) { + val |= OMAP3430_PRM_POLCTRL_CLKREQ_POL; + val &= ~OMAP3430_PRM_POLCTRL_OFFMODE_POL; + pr_debug("PM: fixing sys_clkreq and sys_off_mode polarity to 0x%x\n", + val); + voltdm->write(val, OMAP3_PRM_POLCTRL_OFFSET); + } + + /* + * By default let's use I2C4 signaling for retention idle + * and sys_off_mode pin signaling for off idle. This way we + * have sys_clk_req pin go down for retention and both + * sys_clk_req and sys_off_mode pins will go down for off + * idle. And we can also scale voltages to zero for off-idle. + * Note that no actual voltage scaling during off-idle will + * happen unless the board specific twl4030 PMIC scripts are + * loaded. See also omap_vc_i2c_init for comments regarding + * erratum i531. + */ + val = voltdm->read(OMAP3_PRM_VOLTCTRL_OFFSET); + if (!(val & OMAP3430_PRM_VOLTCTRL_SEL_OFF)) { + val |= OMAP3430_PRM_VOLTCTRL_SEL_OFF; + pr_debug("PM: setting voltctrl sys_off_mode signaling to 0x%x\n", + val); + voltdm->write(val, OMAP3_PRM_VOLTCTRL_OFFSET); + } + vc.voltctrl = val; + + omap3_vc_set_pmic_signaling(PWRDM_POWER_ON); +} + +static void omap3_init_voltsetup1(struct voltagedomain *voltdm, + struct omap3_vc_timings *c, u32 idle) +{ + unsigned long val; + + val = (voltdm->vc_param->on - idle) / voltdm->pmic->slew_rate; + val *= voltdm->sys_clk.rate / 8 / 1000000 + 1; + val <<= __ffs(voltdm->vfsm->voltsetup_mask); + c->voltsetup1 &= ~voltdm->vfsm->voltsetup_mask; + c->voltsetup1 |= val; +} + +/** + * 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. + * + * Note that pmic is not controlling the voltage scaling during + * retention signaled over I2C4, so we can keep voltsetup2 as 0. + * And the oscillator is not shut off over I2C4, so no need to + * set clksetup. + */ +static void omap3_set_i2c_timings(struct voltagedomain *voltdm) +{ + struct omap3_vc_timings *c = vc.timings; + + /* Configure PRWDM_POWER_OFF over I2C4 */ + omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->off); + c++; + /* Configure PRWDM_POWER_RET over I2C4 */ + omap3_init_voltsetup1(voltdm, c, voltdm->vc_param->ret); +} + +/** + * 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.n, + * sys_off_mode has the additional benefit that voltages can be + * scaled to zero volt level with TWL4030 / TWL5030, I2C can only + * scale to 600mV. + * + * Note that omap is not controlling the voltage scaling during + * off idle signaled by sys_off_mode, so we can keep voltsetup1 + * as 0. + */ +static void omap3_set_off_timings(struct voltagedomain *voltdm) +{ + struct omap3_vc_timings *c = vc.timings; + u32 tstart, tshut, clksetup, voltoffset; + + if (c->voltsetup2) + return; + + omap_pm_get_oscillator(&tstart, &tshut); + if (tstart == ULONG_MAX) { + pr_debug("PM: oscillator start-up time not initialized, using 10ms\n"); + clksetup = omap_usec_to_32k(10000); + } else { + clksetup = omap_usec_to_32k(tstart); + } + + /* + * For twl4030 errata 27, we need to allow minimum ~488.32 us wait to + * switch from HFCLKIN to internal oscillator. That means timings + * have voltoffset fixed to 0xa in rounded up 32 KiHz cycles. And + * that means we can calculate the value based on the oscillator + * start-up time since voltoffset2 = clksetup - voltoffset. + */ + voltoffset = omap_usec_to_32k(488); + c->voltsetup2 = clksetup - voltoffset; + voltdm->write(clksetup, OMAP3_PRM_CLKSETUP_OFFSET); + voltdm->write(voltoffset, OMAP3_PRM_VOLTOFFSET_OFFSET); +} + +static void __init omap3_vc_init_channel(struct voltagedomain *voltdm) +{ + omap3_vc_init_pmic_signaling(voltdm); + omap3_set_off_timings(voltdm); + omap3_set_i2c_timings(voltdm); +} + +/** + * omap4_calc_volt_ramp - calculates voltage ramping delays on omap4 + * @voltdm: channel to calculate values for + * @voltage_diff: voltage difference in microvolts + * + * Calculates voltage ramp prescaler + counter values for a voltage + * difference on omap4. Returns a field value suitable for writing to + * VOLTSETUP register for a channel in following format: + * bits[8:9] prescaler ... bits[0:5] counter. See OMAP4 TRM for reference. + */ +static u32 omap4_calc_volt_ramp(struct voltagedomain *voltdm, u32 voltage_diff) +{ + u32 prescaler; + u32 cycles; + u32 time; + + time = voltage_diff / voltdm->pmic->slew_rate; + + cycles = voltdm->sys_clk.rate / 1000 * time / 1000; + + cycles /= 64; + prescaler = 0; + + /* shift to next prescaler until no overflow */ + + /* scale for div 256 = 64 * 4 */ + if (cycles > 63) { + cycles /= 4; + prescaler++; + } + + /* scale for div 512 = 256 * 2 */ + if (cycles > 63) { + cycles /= 2; + prescaler++; + } + + /* scale for div 2048 = 512 * 4 */ + if (cycles > 63) { + cycles /= 4; + prescaler++; + } + + /* check for overflow => invalid ramp time */ + if (cycles > 63) { + pr_warn("%s: invalid setuptime for vdd_%s\n", __func__, + voltdm->name); + return 0; + } + + cycles++; + + return (prescaler << OMAP4430_RAMP_UP_PRESCAL_SHIFT) | + (cycles << OMAP4430_RAMP_UP_COUNT_SHIFT); +} + +/** + * 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 + * + * Calculates and sets the voltage ramp up / down values for a channel. + */ +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, + voltdm->vc_param->on - voltdm->vc_param->off); + offset = voltdm->vfsm->voltsetup_off_reg; + } else { + ramp = omap4_calc_volt_ramp(voltdm, + voltdm->vc_param->on - voltdm->vc_param->ret); + offset = voltdm->vfsm->voltsetup_reg; + } + + if (!ramp) + return; + + val = voltdm->read(offset); + + val |= ramp << OMAP4430_RAMP_DOWN_COUNT_SHIFT; + + 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); + + writel_relaxed(val, OMAP4_SCRM_CLKSETUPTIME); +} + +static void __init omap4_vc_init_pmic_signaling(struct voltagedomain *voltdm) +{ + if (vc.vd) + return; + + vc.vd = voltdm; + voltdm->write(OMAP4_VDD_DEFAULT_VAL, OMAP4_PRM_VOLTCTRL_OFFSET); +} + +/* OMAP4 specific voltage init functions */ +static void __init omap4_vc_init_channel(struct voltagedomain *voltdm) +{ + omap4_vc_init_pmic_signaling(voltdm); + omap4_set_timings(voltdm, true); + omap4_set_timings(voltdm, false); +} + +struct i2c_init_data { + u8 loadbits; + u8 load; + u8 hsscll_38_4; + u8 hsscll_26; + u8 hsscll_19_2; + u8 hsscll_16_8; + u8 hsscll_12; +}; + +static const struct i2c_init_data omap4_i2c_timing_data[] __initconst = { + { + .load = 50, + .loadbits = 0x3, + .hsscll_38_4 = 13, + .hsscll_26 = 11, + .hsscll_19_2 = 9, + .hsscll_16_8 = 9, + .hsscll_12 = 8, + }, + { + .load = 25, + .loadbits = 0x2, + .hsscll_38_4 = 13, + .hsscll_26 = 11, + .hsscll_19_2 = 9, + .hsscll_16_8 = 9, + .hsscll_12 = 8, + }, + { + .load = 12, + .loadbits = 0x1, + .hsscll_38_4 = 11, + .hsscll_26 = 10, + .hsscll_19_2 = 9, + .hsscll_16_8 = 9, + .hsscll_12 = 8, + }, + { + .load = 0, + .loadbits = 0x0, + .hsscll_38_4 = 12, + .hsscll_26 = 10, + .hsscll_19_2 = 9, + .hsscll_16_8 = 8, + .hsscll_12 = 8, + }, +}; + +/** + * omap4_vc_i2c_timing_init - sets up board I2C timing parameters + * @voltdm: voltagedomain pointer to get data from + * + * Use PMIC + board supplied settings for calculating the total I2C + * channel capacitance and set the timing parameters based on this. + * Pre-calculated values are provided in data tables, as it is not + * too straightforward to calculate these runtime. + */ +static void __init omap4_vc_i2c_timing_init(struct voltagedomain *voltdm) +{ + u32 capacitance; + u32 val; + u16 hsscll; + const struct i2c_init_data *i2c_data; + + if (!voltdm->pmic->i2c_high_speed) { + pr_info("%s: using bootloader low-speed timings\n", __func__); + return; + } + + /* PCB trace capacitance, 0.125pF / mm => mm / 8 */ + capacitance = DIV_ROUND_UP(sr_i2c_pcb_length, 8); + + /* OMAP pad capacitance */ + capacitance += 4; + + /* PMIC pad capacitance */ + capacitance += voltdm->pmic->i2c_pad_load; + + /* Search for capacitance match in the table */ + i2c_data = omap4_i2c_timing_data; + + while (i2c_data->load > capacitance) + i2c_data++; + + /* Select proper values based on sysclk frequency */ + switch (voltdm->sys_clk.rate) { + case 38400000: + hsscll = i2c_data->hsscll_38_4; + break; + case 26000000: + hsscll = i2c_data->hsscll_26; + break; + case 19200000: + hsscll = i2c_data->hsscll_19_2; + break; + case 16800000: + hsscll = i2c_data->hsscll_16_8; + break; + case 12000000: + hsscll = i2c_data->hsscll_12; + break; + default: + pr_warn("%s: unsupported sysclk rate: %d!\n", __func__, + voltdm->sys_clk.rate); + return; + } + + /* Loadbits define pull setup for the I2C channels */ + val = i2c_data->loadbits << 25 | i2c_data->loadbits << 29; + + /* Write to SYSCTRL_PADCONF_WKUP_CTRL_I2C_2 to setup I2C pull */ + writel_relaxed(val, OMAP2_L4_IO_ADDRESS(OMAP4_CTRL_MODULE_PAD_WKUP + + OMAP4_CTRL_MODULE_PAD_WKUP_CONTROL_I2C_2)); + + /* HSSCLH can always be zero */ + val = hsscll << OMAP4430_HSSCLL_SHIFT; + val |= (0x28 << OMAP4430_SCLL_SHIFT | 0x2c << OMAP4430_SCLH_SHIFT); + + /* Write setup times to I2C config register */ + voltdm->write(val, OMAP4_PRM_VC_CFG_I2C_CLK_OFFSET); +} + + + +/** + * omap_vc_i2c_init - initialize I2C interface to PMIC + * @voltdm: voltage domain containing VC data + * + * Use PMIC supplied settings for I2C high-speed mode and + * master code (if set) and program the VC I2C configuration + * register. + * + * The VC I2C configuration is common to all VC channels, + * so this function only configures I2C for the first VC + * channel registers. All other VC channels will use the + * same configuration. + */ +static void __init omap_vc_i2c_init(struct voltagedomain *voltdm) +{ + struct omap_vc_channel *vc = voltdm->vc; + static bool initialized; + static bool i2c_high_speed; + u8 mcode; + + if (initialized) { + if (voltdm->pmic->i2c_high_speed != i2c_high_speed) + pr_warn("%s: I2C config for vdd_%s does not match other channels (%u).\n", + __func__, voltdm->name, i2c_high_speed); + return; + } + + /* + * Note that for omap3 OMAP3430_SREN_MASK clears SREN to work around + * erratum i531 "Extra Power Consumed When Repeated Start Operation + * Mode Is Enabled on I2C Interface Dedicated for Smart Reflex (I2C4)". + * Otherwise I2C4 eventually leads into about 23mW extra power being + * consumed even during off idle using VMODE. + */ + i2c_high_speed = voltdm->pmic->i2c_high_speed; + if (i2c_high_speed) + voltdm->rmw(vc->common->i2c_cfg_clear_mask, + vc->common->i2c_cfg_hsen_mask, + vc->common->i2c_cfg_reg); + + mcode = voltdm->pmic->i2c_mcode; + if (mcode) + voltdm->rmw(vc->common->i2c_mcode_mask, + mcode << __ffs(vc->common->i2c_mcode_mask), + vc->common->i2c_cfg_reg); + + if (cpu_is_omap44xx()) + omap4_vc_i2c_timing_init(voltdm); + + initialized = true; +} + +/** + * omap_vc_calc_vsel - calculate vsel value for a channel + * @voltdm: channel to calculate value for + * @uvolt: microvolt value to convert to vsel + * + * Converts a microvolt value to vsel value for the used PMIC. + * This checks whether the microvolt value is out of bounds, and + * adjusts the value accordingly. If unsupported value detected, + * warning is thrown. + */ +static u8 omap_vc_calc_vsel(struct voltagedomain *voltdm, u32 uvolt) +{ + if (voltdm->pmic->vddmin > uvolt) + uvolt = voltdm->pmic->vddmin; + if (voltdm->pmic->vddmax < uvolt) { + WARN(1, "%s: voltage not supported by pmic: %u vs max %u\n", + __func__, uvolt, voltdm->pmic->vddmax); + /* Lets try maximum value anyway */ + uvolt = voltdm->pmic->vddmax; + } + + return voltdm->pmic->uv_to_vsel(uvolt); +} + +#ifdef CONFIG_PM +/** + * omap_pm_setup_sr_i2c_pcb_length - set length of SR I2C traces on PCB + * @mm: length of the PCB trace in millimetres + * + * Sets the PCB trace length for the I2C channel. By default uses 63mm. + * This is needed for properly calculating the capacitance value for + * the PCB trace, and for setting the SR I2C channel timing parameters. + */ +void __init omap_pm_setup_sr_i2c_pcb_length(u32 mm) +{ + sr_i2c_pcb_length = mm; +} +#endif + +void __init omap_vc_init_channel(struct voltagedomain *voltdm) +{ + struct omap_vc_channel *vc = voltdm->vc; + u8 on_vsel, onlp_vsel, ret_vsel, off_vsel; + u32 val; + + 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; + } + + vc->cfg_channel = 0; + if (vc->flags & OMAP_VC_CHANNEL_CFG_MUTANT) + vc_cfg_bits = &vc_mutant_channel_cfg; + else + vc_cfg_bits = &vc_default_channel_cfg; + + /* get PMIC/board specific settings */ + vc->i2c_slave_addr = voltdm->pmic->i2c_slave_addr; + vc->volt_reg_addr = voltdm->pmic->volt_reg_addr; + vc->cmd_reg_addr = voltdm->pmic->cmd_reg_addr; + + /* Configure the i2c slave address for this VC */ + voltdm->rmw(vc->smps_sa_mask, + vc->i2c_slave_addr << __ffs(vc->smps_sa_mask), + vc->smps_sa_reg); + vc->cfg_channel |= vc_cfg_bits->sa; + + /* + * Configure the PMIC register addresses. + */ + voltdm->rmw(vc->smps_volra_mask, + vc->volt_reg_addr << __ffs(vc->smps_volra_mask), + vc->smps_volra_reg); + vc->cfg_channel |= vc_cfg_bits->rav; + + if (vc->cmd_reg_addr) { + voltdm->rmw(vc->smps_cmdra_mask, + vc->cmd_reg_addr << __ffs(vc->smps_cmdra_mask), + vc->smps_cmdra_reg); + vc->cfg_channel |= vc_cfg_bits->rac; + } + + if (vc->cmd_reg_addr == vc->volt_reg_addr) + vc->cfg_channel |= vc_cfg_bits->racen; + + /* Set up the on, inactive, retention and off voltage */ + on_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->on); + onlp_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->onlp); + ret_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->ret); + off_vsel = omap_vc_calc_vsel(voltdm, voltdm->vc_param->off); + + val = ((on_vsel << vc->common->cmd_on_shift) | + (onlp_vsel << vc->common->cmd_onlp_shift) | + (ret_vsel << vc->common->cmd_ret_shift) | + (off_vsel << vc->common->cmd_off_shift)); + voltdm->write(val, vc->cmdval_reg); + vc->cfg_channel |= vc_cfg_bits->cmd; + + /* Channel configuration */ + omap_vc_config_channel(voltdm); + + omap_vc_i2c_init(voltdm); + + if (cpu_is_omap34xx()) + omap3_vc_init_channel(voltdm); + else if (cpu_is_omap44xx()) + omap4_vc_init_channel(voltdm); +} |