1 files changed, 424 insertions, 29 deletions

diff --git a/arch/arm/mach-omap2/vc.c b/arch/arm/mach-omap2/vc.c
index 75878c37959b..49ac7977e03e 100644
--- a/arch/arm/mach-omap2/vc.c
+++ b/arch/arm/mach-omap2/vc.c
@@ -11,13 +11,20 @@
 #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
@@ -63,6 +70,9 @@ static struct omap_vc_channel_cfg vc_mutant_channel_cfg = {
 };
 
 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
 
 /**
@@ -135,6 +145,8 @@ int omap_vc_pre_scale(struct voltagedomain *voltdm,
         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;
@@ -202,46 +214,389 @@ int omap_vc_bypass_scale(struct voltagedomain *voltdm,
         return 0;
 }
 
-static void __init omap3_vfsm_init(struct voltagedomain *voltdm)
+/* 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);
+
         /*
-         * Voltage Manager FSM parameters init
-         * XXX This data should be passed in from the board file
+         * pmic is not controlling the voltage scaling during retention,
+         * thus set voltsetup2 to 0
          */
-        voltdm->write(OMAP3_CLKSETUP, OMAP3_PRM_CLKSETUP_OFFSET);
-        voltdm->write(OMAP3_VOLTOFFSET, OMAP3_PRM_VOLTOFFSET_OFFSET);
-        voltdm->write(OMAP3_VOLTSETUP2, OMAP3_PRM_VOLTSETUP2_OFFSET);
+        voltdm->write(0, OMAP3_PRM_VOLTSETUP2_OFFSET);
 }
 
-static void __init omap3_vc_init_channel(struct voltagedomain *voltdm)
+/**
+ * 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
+ * scaled to zero volt level with TWL4030 / TWL5030, I2C can only
+ * scale to 600mV.
+ */
+static void omap3_set_off_timings(struct voltagedomain *voltdm)
 {
-        static bool is_initialized;
+        unsigned long clksetup;
+        unsigned long voltsetup2;
+        unsigned long voltsetup2_old;
+        u32 val;
+        u32 tstart, tshut;
 
-        if (is_initialized)
+        /* check if sys_off_mode is used to control off-mode voltages */
+        val = voltdm->read(OMAP3_PRM_VOLTCTRL_OFFSET);
+        if (!(val & OMAP3430_SEL_OFF_MASK)) {
+                /* No, omap is controlling them over I2C */
+                omap3_set_i2c_timings(voltdm, true);
                 return;
+        }
+
+        omap_pm_get_oscillator(&tstart, &tshut);
+        omap3_set_clksetup(tstart, voltdm);
+
+        clksetup = voltdm->read(OMAP3_PRM_CLKSETUP_OFFSET);
+
+        /* voltsetup 2 in us */
+        voltsetup2 = voltdm->vc_param->on / voltdm->pmic->slew_rate;
+
+        /* convert to 32k clk cycles */
+        voltsetup2 = DIV_ROUND_UP(voltsetup2 * 32768, 1000000);
+
+        voltsetup2_old = voltdm->read(OMAP3_PRM_VOLTSETUP2_OFFSET);
+
+        /*
+         * Update voltsetup2 if higher than current value (needed because
+         * we have multiple channels with different ramp times), also
+         * update voltoffset always to value recommended by TRM
+         */
+        if (voltsetup2 > voltsetup2_old) {
+                voltdm->write(voltsetup2, OMAP3_PRM_VOLTSETUP2_OFFSET);
+                voltdm->write(clksetup - voltsetup2,
+                        OMAP3_PRM_VOLTOFFSET_OFFSET);
+        } else
+                voltdm->write(clksetup - voltsetup2_old,
+                        OMAP3_PRM_VOLTOFFSET_OFFSET);
+
+        /*
+         * omap is not controlling voltage scaling during off-mode,
+         * thus set voltsetup1 to 0
+         */
+        voltdm->rmw(voltdm->vfsm->voltsetup_mask, 0,
+                voltdm->vfsm->voltsetup_reg);
+
+        /* voltoffset must be clksetup minus voltsetup2 according to TRM */
+        voltdm->write(clksetup - voltsetup2, OMAP3_PRM_VOLTOFFSET_OFFSET);
+}
+
+static void __init omap3_vc_init_channel(struct voltagedomain *voltdm)
+{
+        omap3_set_off_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++;
 
-        omap3_vfsm_init(voltdm);
+        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;
 
-        is_initialized = true;
+        /* 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);
+
+        __raw_writel(val, OMAP4_SCRM_CLKSETUPTIME);
+}
 
 /* OMAP4 specific voltage init functions */
 static void __init omap4_vc_init_channel(struct voltagedomain *voltdm)
 {
-        static bool is_initialized;
-        u32 vc_val;
+        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;
+};
 
-        if (is_initialized)
+static const __initdata struct i2c_init_data omap4_i2c_timing_data[] = {
+        {
+                .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_warn("%s: only high speed supported!\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;
+        }
 
-        /* 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);
+        /* Loadbits define pull setup for the I2C channels */
+        val = i2c_data->loadbits << 25 | i2c_data->loadbits << 29;
 
-        is_initialized = true;
+        /* Write to SYSCTRL_PADCONF_WKUP_CTRL_I2C_2 to setup I2C pull */
+        __raw_writel(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
@@ -281,9 +636,51 @@ static void __init omap_vc_i2c_init(struct voltagedomain *voltdm)
                             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;
@@ -311,7 +708,6 @@ void __init omap_vc_init_channel(struct voltagedomain *voltdm)
         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,
@@ -331,14 +727,18 @@ void __init omap_vc_init_channel(struct voltagedomain *voltdm)
                 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;
+                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 = 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);
+        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) |
@@ -349,11 +749,6 @@ void __init omap_vc_init_channel(struct voltagedomain *voltdm)
         /* 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())