OMAP2+: voltage: split out voltage processor (VP) code into new layer

This patch is primarily a move of VP specific code from voltage.c into
its own code in vp.c and adds prototypes to vp.h

No functional changes, except debugfs...

VP debugfs moved to 'vp' subdir of <debugfs>/voltage/ and 'vp_'
prefixes removed from all debugfs filenames.

Signed-off-by: Kevin Hilman <khilman@ti.com>

1 files changed, 374 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/vp.c b/arch/arm/mach-omap2/vp.c
new file mode 100644
index 00000000000..f3503de5d8f
--- /dev/null
+++ b/arch/arm/mach-omap2/vp.c
@@ -0,0 +1,374 @@
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/debugfs.h>
+
+#include <plat/common.h>
+
+#include "voltage.h"
+#include "vp.h"
+#include "prm-regbits-34xx.h"
+#include "prm-regbits-44xx.h"
+#include "prm44xx.h"
+
+static void __init vp_debugfs_init(struct voltagedomain *voltdm);
+
+static void vp_latch_vsel(struct voltagedomain *voltdm)
+{
+	struct omap_vp_instance_data *vp = voltdm->vdd->vp_data;
+	u32 vpconfig;
+	unsigned long uvdc;
+	char vsel;
+	struct omap_vdd_info *vdd = voltdm->vdd;
+
+	uvdc = omap_voltage_get_nom_volt(voltdm);
+	if (!uvdc) {
+		pr_warning("%s: unable to find current voltage for vdd_%s\n",
+			__func__, voltdm->name);
+		return;
+	}
+
+	if (!vdd->pmic_info || !vdd->pmic_info->uv_to_vsel) {
+		pr_warning("%s: PMIC function to convert voltage in uV to"
+			" vsel not registered\n", __func__);
+		return;
+	}
+
+	vsel = vdd->pmic_info->uv_to_vsel(uvdc);
+
+	vpconfig = vdd->read_reg(vp->vp_common->prm_mod, vp->vpconfig);
+	vpconfig &= ~(vp->vp_common->vpconfig_initvoltage_mask |
+			vp->vp_common->vpconfig_initvdd);
+	vpconfig |= vsel << vp->vp_common->vpconfig_initvoltage_shift;
+
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+
+	/* Trigger initVDD value copy to voltage processor */
+	vdd->write_reg((vpconfig | vp->vp_common->vpconfig_initvdd),
+		       vp->vp_common->prm_mod, vp->vpconfig);
+
+	/* Clear initVDD copy trigger bit */
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+}
+
+/* Generic voltage init functions */
+void __init omap_vp_init(struct voltagedomain *voltdm)
+{
+	struct omap_vp_instance_data *vp = voltdm->vdd->vp_data;
+	struct omap_vdd_info *vdd = voltdm->vdd;
+	u32 vp_val;
+
+	if (!vdd->read_reg || !vdd->write_reg) {
+		pr_err("%s: No read/write API for accessing vdd_%s regs\n",
+			__func__, voltdm->name);
+		return;
+	}
+
+	vp_val = vdd->vp_rt_data.vpconfig_erroroffset |
+		(vdd->vp_rt_data.vpconfig_errorgain <<
+		vp->vp_common->vpconfig_errorgain_shift) |
+		vp->vp_common->vpconfig_timeouten;
+	vdd->write_reg(vp_val, vp->vp_common->prm_mod, vp->vpconfig);
+
+	vp_val = ((vdd->vp_rt_data.vstepmin_smpswaittimemin <<
+		vp->vp_common->vstepmin_smpswaittimemin_shift) |
+		(vdd->vp_rt_data.vstepmin_stepmin <<
+		vp->vp_common->vstepmin_stepmin_shift));
+	vdd->write_reg(vp_val, vp->vp_common->prm_mod, vp->vstepmin);
+
+	vp_val = ((vdd->vp_rt_data.vstepmax_smpswaittimemax <<
+		vp->vp_common->vstepmax_smpswaittimemax_shift) |
+		(vdd->vp_rt_data.vstepmax_stepmax <<
+		vp->vp_common->vstepmax_stepmax_shift));
+	vdd->write_reg(vp_val, vp->vp_common->prm_mod, vp->vstepmax);
+
+	vp_val = ((vdd->vp_rt_data.vlimitto_vddmax <<
+		vp->vp_common->vlimitto_vddmax_shift) |
+		(vdd->vp_rt_data.vlimitto_vddmin <<
+		vp->vp_common->vlimitto_vddmin_shift) |
+		(vdd->vp_rt_data.vlimitto_timeout <<
+		vp->vp_common->vlimitto_timeout_shift));
+	vdd->write_reg(vp_val, vp->vp_common->prm_mod, vp->vlimitto);
+
+	vp_debugfs_init(voltdm);
+}
+
+/* VP force update method of voltage scaling */
+int omap_vp_forceupdate_scale(struct voltagedomain *voltdm,
+			      unsigned long target_volt)
+{
+	struct omap_vp_instance_data *vp = voltdm->vdd->vp_data;
+	struct omap_vdd_info *vdd = voltdm->vdd;
+	u32 vpconfig;
+	u8 target_vsel, current_vsel;
+	int ret, timeout = 0;
+
+	ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, &current_vsel);
+	if (ret)
+		return ret;
+
+	/*
+	 * Clear all pending TransactionDone interrupt/status. Typical latency
+	 * is <3us
+	 */
+	while (timeout++ < VP_TRANXDONE_TIMEOUT) {
+		vdd->write_reg(vp->prm_irqst_data->tranxdone_status,
+			       vdd->prm_irqst_mod, vdd->prm_irqst_reg);
+		if (!(vdd->read_reg(vdd->prm_irqst_mod, vdd->prm_irqst_reg) &
+		      vp->prm_irqst_data->tranxdone_status))
+			break;
+		udelay(1);
+	}
+	if (timeout >= VP_TRANXDONE_TIMEOUT) {
+		pr_warning("%s: vdd_%s TRANXDONE timeout exceeded."
+			"Voltage change aborted", __func__, voltdm->name);
+		return -ETIMEDOUT;
+	}
+
+	/* Configure for VP-Force Update */
+	vpconfig = vdd->read_reg(vp->vp_common->prm_mod, vp->vpconfig);
+	vpconfig &= ~(vp->vp_common->vpconfig_initvdd |
+			vp->vp_common->vpconfig_forceupdate |
+			vp->vp_common->vpconfig_initvoltage_mask);
+	vpconfig |= ((target_vsel <<
+			vp->vp_common->vpconfig_initvoltage_shift));
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+
+	/* Trigger initVDD value copy to voltage processor */
+	vpconfig |= vp->vp_common->vpconfig_initvdd;
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+
+	/* Force update of voltage */
+	vpconfig |= vp->vp_common->vpconfig_forceupdate;
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+
+	/*
+	 * Wait for TransactionDone. Typical latency is <200us.
+	 * Depends on SMPSWAITTIMEMIN/MAX and voltage change
+	 */
+	timeout = 0;
+	omap_test_timeout((vdd->read_reg(vdd->prm_irqst_mod,
+					 vdd->prm_irqst_reg) &
+			   vp->prm_irqst_data->tranxdone_status),
+			  VP_TRANXDONE_TIMEOUT, timeout);
+	if (timeout >= VP_TRANXDONE_TIMEOUT)
+		pr_err("%s: vdd_%s TRANXDONE timeout exceeded."
+			"TRANXDONE never got set after the voltage update\n",
+			__func__, voltdm->name);
+
+	omap_vc_post_scale(voltdm, target_volt, target_vsel, current_vsel);
+
+	/*
+	 * Disable TransactionDone interrupt , clear all status, clear
+	 * control registers
+	 */
+	timeout = 0;
+	while (timeout++ < VP_TRANXDONE_TIMEOUT) {
+		vdd->write_reg(vp->prm_irqst_data->tranxdone_status,
+			       vdd->prm_irqst_mod, vdd->prm_irqst_reg);
+		if (!(vdd->read_reg(vdd->prm_irqst_mod, vdd->prm_irqst_reg) &
+		      vp->prm_irqst_data->tranxdone_status))
+			break;
+		udelay(1);
+	}
+
+	if (timeout >= VP_TRANXDONE_TIMEOUT)
+		pr_warning("%s: vdd_%s TRANXDONE timeout exceeded while trying"
+			"to clear the TRANXDONE status\n",
+			__func__, voltdm->name);
+
+	vpconfig = vdd->read_reg(vp->vp_common->prm_mod, vp->vpconfig);
+	/* Clear initVDD copy trigger bit */
+	vpconfig &= ~vp->vp_common->vpconfig_initvdd;
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+	/* Clear force bit */
+	vpconfig &= ~vp->vp_common->vpconfig_forceupdate;
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+
+	return 0;
+}
+
+/**
+ * omap_vp_get_curr_volt() - API to get the current vp voltage.
+ * @voltdm:	pointer to the VDD.
+ *
+ * This API returns the current voltage for the specified voltage processor
+ */
+unsigned long omap_vp_get_curr_volt(struct voltagedomain *voltdm)
+{
+	struct omap_vp_instance_data *vp = voltdm->vdd->vp_data;
+	struct omap_vdd_info *vdd;
+	u8 curr_vsel;
+
+	if (!voltdm || IS_ERR(voltdm)) {
+		pr_warning("%s: VDD specified does not exist!\n", __func__);
+		return 0;
+	}
+
+	vdd = voltdm->vdd;
+	if (!vdd->read_reg) {
+		pr_err("%s: No read API for reading vdd_%s regs\n",
+			__func__, voltdm->name);
+		return 0;
+	}
+
+	curr_vsel = vdd->read_reg(vp->vp_common->prm_mod, vp->voltage);
+
+	if (!vdd->pmic_info || !vdd->pmic_info->vsel_to_uv) {
+		pr_warning("%s: PMIC function to convert vsel to voltage"
+			"in uV not registerd\n", __func__);
+		return 0;
+	}
+
+	return vdd->pmic_info->vsel_to_uv(curr_vsel);
+}
+
+/**
+ * omap_vp_enable() - API to enable a particular VP
+ * @voltdm:	pointer to the VDD whose VP is to be enabled.
+ *
+ * This API enables a particular voltage processor. Needed by the smartreflex
+ * class drivers.
+ */
+void omap_vp_enable(struct voltagedomain *voltdm)
+{
+	struct omap_vp_instance_data *vp;
+	struct omap_vdd_info *vdd;
+	u32 vpconfig;
+
+	if (!voltdm || IS_ERR(voltdm)) {
+		pr_warning("%s: VDD specified does not exist!\n", __func__);
+		return;
+	}
+
+	vdd = voltdm->vdd;
+	vp = voltdm->vdd->vp_data;
+	if (!vdd->read_reg || !vdd->write_reg) {
+		pr_err("%s: No read/write API for accessing vdd_%s regs\n",
+			__func__, voltdm->name);
+		return;
+	}
+
+	/* If VP is already enabled, do nothing. Return */
+	if (vdd->vp_enabled)
+		return;
+
+	vp_latch_vsel(voltdm);
+
+	/* Enable VP */
+	vpconfig = vdd->read_reg(vp->vp_common->prm_mod, vp->vpconfig);
+	vpconfig |= vp->vp_common->vpconfig_vpenable;
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+	vdd->vp_enabled = true;
+}
+
+/**
+ * omap_vp_disable() - API to disable a particular VP
+ * @voltdm:	pointer to the VDD whose VP is to be disabled.
+ *
+ * This API disables a particular voltage processor. Needed by the smartreflex
+ * class drivers.
+ */
+void omap_vp_disable(struct voltagedomain *voltdm)
+{
+	struct omap_vp_instance_data *vp;
+	struct omap_vdd_info *vdd;
+	u32 vpconfig;
+	int timeout;
+
+	if (!voltdm || IS_ERR(voltdm)) {
+		pr_warning("%s: VDD specified does not exist!\n", __func__);
+		return;
+	}
+
+	vdd = voltdm->vdd;
+	vp = voltdm->vdd->vp_data;
+	if (!vdd->read_reg || !vdd->write_reg) {
+		pr_err("%s: No read/write API for accessing vdd_%s regs\n",
+			__func__, voltdm->name);
+		return;
+	}
+
+	/* If VP is already disabled, do nothing. Return */
+	if (!vdd->vp_enabled) {
+		pr_warning("%s: Trying to disable VP for vdd_%s when"
+			"it is already disabled\n", __func__, voltdm->name);
+		return;
+	}
+
+	/* Disable VP */
+	vpconfig = vdd->read_reg(vp->vp_common->prm_mod, vp->vpconfig);
+	vpconfig &= ~vp->vp_common->vpconfig_vpenable;
+	vdd->write_reg(vpconfig, vp->vp_common->prm_mod, vp->vpconfig);
+
+	/*
+	 * Wait for VP idle Typical latency is <2us. Maximum latency is ~100us
+	 */
+	omap_test_timeout((vdd->read_reg(vp->vp_common->prm_mod, vp->vstatus)),
+				VP_IDLE_TIMEOUT, timeout);
+
+	if (timeout >= VP_IDLE_TIMEOUT)
+		pr_warning("%s: vdd_%s idle timedout\n",
+			__func__, voltdm->name);
+
+	vdd->vp_enabled = false;
+
+	return;
+}
+
+/* Voltage debugfs support */
+static int vp_volt_debug_get(void *data, u64 *val)
+{
+	struct voltagedomain *voltdm = (struct voltagedomain *)data;
+	struct omap_vp_instance_data *vp = voltdm->vdd->vp_data;
+	struct omap_vdd_info *vdd = voltdm->vdd;
+	u8 vsel;
+
+	if (!vdd) {
+		pr_warning("Wrong paramater passed\n");
+		return -EINVAL;
+	}
+
+	vsel = vdd->read_reg(vp->vp_common->prm_mod, vp->voltage);
+
+	if (!vdd->pmic_info->vsel_to_uv) {
+		pr_warning("PMIC function to convert vsel to voltage"
+			"in uV not registerd\n");
+		return -EINVAL;
+	}
+
+	*val = vdd->pmic_info->vsel_to_uv(vsel);
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(vp_volt_debug_fops, vp_volt_debug_get, NULL, "%llu\n");
+
+static void __init vp_debugfs_init(struct voltagedomain *voltdm)
+{
+	struct omap_vdd_info *vdd = voltdm->vdd;
+	struct dentry *debug_dir;
+
+	debug_dir = debugfs_create_dir("vp", vdd->debug_dir);
+	if (IS_ERR(debug_dir))
+		pr_err("%s: Unable to create VP debugfs dir dir\n", __func__);
+
+	(void) debugfs_create_x16("errorgain", S_IRUGO, debug_dir,
+				&(vdd->vp_rt_data.vpconfig_errorgain));
+	(void) debugfs_create_x16("smpswaittimemin", S_IRUGO,
+				debug_dir,
+				&(vdd->vp_rt_data.vstepmin_smpswaittimemin));
+	(void) debugfs_create_x8("stepmin", S_IRUGO, debug_dir,
+				&(vdd->vp_rt_data.vstepmin_stepmin));
+	(void) debugfs_create_x16("smpswaittimemax", S_IRUGO,
+				debug_dir,
+				&(vdd->vp_rt_data.vstepmax_smpswaittimemax));
+	(void) debugfs_create_x8("stepmax", S_IRUGO, debug_dir,
+				&(vdd->vp_rt_data.vstepmax_stepmax));
+	(void) debugfs_create_x8("vddmax", S_IRUGO, debug_dir,
+				&(vdd->vp_rt_data.vlimitto_vddmax));
+	(void) debugfs_create_x8("vddmin", S_IRUGO, debug_dir,
+				&(vdd->vp_rt_data.vlimitto_vddmin));
+	(void) debugfs_create_x16("timeout", S_IRUGO, debug_dir,
+				&(vdd->vp_rt_data.vlimitto_timeout));
+	(void) debugfs_create_file("curr_volt", S_IRUGO, debug_dir,
+				(void *) voltdm, &vp_volt_debug_fops);
+}