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author | Arnd Bergmann <arnd@arndb.de> | 2011-10-31 00:22:54 +0100 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2011-10-31 00:22:54 +0100 |
commit | c6c3a3a03e6de52866bc81a32fc551733625d553 (patch) | |
tree | b55967a9163dba315e2543d648de758b82c85fa1 /arch/arm/mach-omap2/vc.c | |
parent | ARM: SAMSUNG: Move fimc plat. device from board files to plat-samsung (diff) | |
parent | ARM: OMAP: Warn if omap_ioremap is called before SoC detection (diff) | |
download | linux-c6c3a3a03e6de52866bc81a32fc551733625d553.tar.xz linux-c6c3a3a03e6de52866bc81a32fc551733625d553.zip |
Merge branch 'omap/cleanup' into next/cleanup2
Diffstat (limited to 'arch/arm/mach-omap2/vc.c')
-rw-r--r-- | arch/arm/mach-omap2/vc.c | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/vc.c b/arch/arm/mach-omap2/vc.c new file mode 100644 index 000000000000..031d116fbf10 --- /dev/null +++ b/arch/arm/mach-omap2/vc.c @@ -0,0 +1,367 @@ +/* + * 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 <plat/cpu.h> + +#include "voltage.h" +#include "vc.h" +#include "prm-regbits-34xx.h" +#include "prm-regbits-44xx.h" +#include "prm44xx.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; +#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); + + 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; +} + +static void __init omap3_vfsm_init(struct voltagedomain *voltdm) +{ + /* + * Voltage Manager FSM parameters init + * XXX This data should be passed in from the board file + */ + voltdm->write(OMAP3_CLKSETUP, OMAP3_PRM_CLKSETUP_OFFSET); + voltdm->write(OMAP3_VOLTOFFSET, OMAP3_PRM_VOLTOFFSET_OFFSET); + voltdm->write(OMAP3_VOLTSETUP2, OMAP3_PRM_VOLTSETUP2_OFFSET); +} + +static void __init omap3_vc_init_channel(struct voltagedomain *voltdm) +{ + static bool is_initialized; + + if (is_initialized) + return; + + omap3_vfsm_init(voltdm); + + is_initialized = true; +} + + +/* OMAP4 specific voltage init functions */ +static void __init omap4_vc_init_channel(struct voltagedomain *voltdm) +{ + static bool is_initialized; + u32 vc_val; + + if (is_initialized) + return; + + /* XXX These are magic numbers and do not belong! */ + vc_val = (0x60 << OMAP4430_SCLL_SHIFT | 0x26 << OMAP4430_SCLH_SHIFT); + voltdm->write(vc_val, OMAP4_PRM_VC_CFG_I2C_CLK_OFFSET); + + is_initialized = true; +} + +/** + * omap_vc_i2c_init - initialize I2C interface to PMIC + * @voltdm: voltage domain containing VC data + * + * Use PMIC supplied seetings 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 all channels must match.", + __func__); + return; + } + + i2c_high_speed = voltdm->pmic->i2c_high_speed; + if (i2c_high_speed) + voltdm->rmw(vc->common->i2c_cfg_hsen_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); + + initialized = true; +} + +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: PMIC info requried to configure vc for" + "vdd_%s not populated.Hence cannot initialize vc\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; + vc->setup_time = voltdm->pmic->volt_setup_time; + + /* 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 | vc_cfg_bits->racen; + } + + /* Set up the on, inactive, retention and off voltage */ + on_vsel = voltdm->pmic->uv_to_vsel(voltdm->pmic->on_volt); + onlp_vsel = voltdm->pmic->uv_to_vsel(voltdm->pmic->onlp_volt); + ret_vsel = voltdm->pmic->uv_to_vsel(voltdm->pmic->ret_volt); + off_vsel = voltdm->pmic->uv_to_vsel(voltdm->pmic->off_volt); + 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); + + /* Configure the setup times */ + voltdm->rmw(voltdm->vfsm->voltsetup_mask, + vc->setup_time << __ffs(voltdm->vfsm->voltsetup_mask), + voltdm->vfsm->voltsetup_reg); + + omap_vc_i2c_init(voltdm); + + if (cpu_is_omap34xx()) + omap3_vc_init_channel(voltdm); + else if (cpu_is_omap44xx()) + omap4_vc_init_channel(voltdm); +} + |