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())