1 files changed, 283 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/vp.c b/arch/arm/mach-omap2/vp.c
new file mode 100644
index 000000000..a709655b9
--- /dev/null
+++ b/arch/arm/mach-omap2/vp.c
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/init.h>
+
+#include "common.h"
+
+#include "voltage.h"
+#include "vp.h"
+#include "prm-regbits-34xx.h"
+#include "prm-regbits-44xx.h"
+#include "prm44xx.h"
+
+static u32 _vp_set_init_voltage(struct voltagedomain *voltdm, u32 volt)
+{
+	struct omap_vp_instance *vp = voltdm->vp;
+	u32 vpconfig;
+	char vsel;
+
+	vsel = voltdm->pmic->uv_to_vsel(volt);
+
+	vpconfig = voltdm->read(vp->vpconfig);
+	vpconfig &= ~(vp->common->vpconfig_initvoltage_mask |
+		      vp->common->vpconfig_forceupdate |
+		      vp->common->vpconfig_initvdd);
+	vpconfig |= vsel << __ffs(vp->common->vpconfig_initvoltage_mask);
+	voltdm->write(vpconfig, vp->vpconfig);
+
+	/* Trigger initVDD value copy to voltage processor */
+	voltdm->write((vpconfig | vp->common->vpconfig_initvdd),
+		       vp->vpconfig);
+
+	/* Clear initVDD copy trigger bit */
+	voltdm->write(vpconfig, vp->vpconfig);
+
+	return vpconfig;
+}
+
+/* Generic voltage init functions */
+void __init omap_vp_init(struct voltagedomain *voltdm)
+{
+	struct omap_vp_instance *vp = voltdm->vp;
+	u32 val, sys_clk_rate, timeout, waittime;
+	u32 vddmin, vddmax, vstepmin, vstepmax;
+
+	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;
+	}
+
+	vp->enabled = false;
+
+	/* Divide to avoid overflow */
+	sys_clk_rate = voltdm->sys_clk.rate / 1000;
+
+	timeout = (sys_clk_rate * voltdm->pmic->vp_timeout_us) / 1000;
+	vddmin = max(voltdm->vp_param->vddmin, voltdm->pmic->vddmin);
+	vddmax = min(voltdm->vp_param->vddmax, voltdm->pmic->vddmax);
+	vddmin = voltdm->pmic->uv_to_vsel(vddmin);
+	vddmax = voltdm->pmic->uv_to_vsel(vddmax);
+
+	waittime = DIV_ROUND_UP(voltdm->pmic->step_size * sys_clk_rate,
+				1000 * voltdm->pmic->slew_rate);
+	vstepmin = voltdm->pmic->vp_vstepmin;
+	vstepmax = voltdm->pmic->vp_vstepmax;
+
+	/*
+	 * VP_CONFIG: error gain is not set here, it will be updated
+	 * on each scale, based on OPP.
+	 */
+	val = (voltdm->pmic->vp_erroroffset <<
+	       __ffs(voltdm->vp->common->vpconfig_erroroffset_mask)) |
+		vp->common->vpconfig_timeouten;
+	voltdm->write(val, vp->vpconfig);
+
+	/* VSTEPMIN */
+	val = (waittime << vp->common->vstepmin_smpswaittimemin_shift) |
+		(vstepmin <<  vp->common->vstepmin_stepmin_shift);
+	voltdm->write(val, vp->vstepmin);
+
+	/* VSTEPMAX */
+	val = (vstepmax << vp->common->vstepmax_stepmax_shift) |
+		(waittime << vp->common->vstepmax_smpswaittimemax_shift);
+	voltdm->write(val, vp->vstepmax);
+
+	/* VLIMITTO */
+	val = (vddmax << vp->common->vlimitto_vddmax_shift) |
+		(vddmin << vp->common->vlimitto_vddmin_shift) |
+		(timeout <<  vp->common->vlimitto_timeout_shift);
+	voltdm->write(val, vp->vlimitto);
+}
+
+int omap_vp_update_errorgain(struct voltagedomain *voltdm,
+			     unsigned long target_volt)
+{
+	struct omap_volt_data *volt_data;
+
+	if (!voltdm->vp)
+		return -EINVAL;
+
+	/* Get volt_data corresponding to target_volt */
+	volt_data = omap_voltage_get_voltdata(voltdm, target_volt);
+	if (IS_ERR(volt_data))
+		return -EINVAL;
+
+	/* Setting vp errorgain based on the voltage */
+	voltdm->rmw(voltdm->vp->common->vpconfig_errorgain_mask,
+		    volt_data->vp_errgain <<
+		    __ffs(voltdm->vp->common->vpconfig_errorgain_mask),
+		    voltdm->vp->vpconfig);
+
+	return 0;
+}
+
+/* VP force update method of voltage scaling */
+int omap_vp_forceupdate_scale(struct voltagedomain *voltdm,
+			      unsigned long target_volt)
+{
+	struct omap_vp_instance *vp = voltdm->vp;
+	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) {
+		vp->common->ops->clear_txdone(vp->id);
+		if (!vp->common->ops->check_txdone(vp->id))
+			break;
+		udelay(1);
+	}
+	if (timeout >= VP_TRANXDONE_TIMEOUT) {
+		pr_warn("%s: vdd_%s TRANXDONE timeout exceeded. Voltage change aborted\n",
+			__func__, voltdm->name);
+		return -ETIMEDOUT;
+	}
+
+	vpconfig = _vp_set_init_voltage(voltdm, target_volt);
+
+	/* Force update of voltage */
+	voltdm->write(vpconfig | vp->common->vpconfig_forceupdate,
+		      voltdm->vp->vpconfig);
+
+	/*
+	 * Wait for TransactionDone. Typical latency is <200us.
+	 * Depends on SMPSWAITTIMEMIN/MAX and voltage change
+	 */
+	timeout = 0;
+	omap_test_timeout(vp->common->ops->check_txdone(vp->id),
+			  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) {
+		vp->common->ops->clear_txdone(vp->id);
+		if (!vp->common->ops->check_txdone(vp->id))
+			break;
+		udelay(1);
+	}
+
+	if (timeout >= VP_TRANXDONE_TIMEOUT)
+		pr_warn("%s: vdd_%s TRANXDONE timeout exceeded while trying to clear the TRANXDONE status\n",
+			__func__, voltdm->name);
+
+	/* Clear force bit */
+	voltdm->write(vpconfig, vp->vpconfig);
+
+	return 0;
+}
+
+/**
+ * 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 *vp;
+	u32 vpconfig, volt;
+
+	if (!voltdm || IS_ERR(voltdm)) {
+		pr_warn("%s: VDD specified does not exist!\n", __func__);
+		return;
+	}
+
+	vp = voltdm->vp;
+	if (!voltdm->read || !voltdm->write) {
+		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 (vp->enabled)
+		return;
+
+	volt = voltdm_get_voltage(voltdm);
+	if (!volt) {
+		pr_warn("%s: unable to find current voltage for %s\n",
+			__func__, voltdm->name);
+		return;
+	}
+
+	vpconfig = _vp_set_init_voltage(voltdm, volt);
+
+	/* Enable VP */
+	vpconfig |= vp->common->vpconfig_vpenable;
+	voltdm->write(vpconfig, vp->vpconfig);
+
+	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 *vp;
+	u32 vpconfig;
+	int timeout;
+
+	if (!voltdm || IS_ERR(voltdm)) {
+		pr_warn("%s: VDD specified does not exist!\n", __func__);
+		return;
+	}
+
+	vp = voltdm->vp;
+	if (!voltdm->read || !voltdm->write) {
+		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 (!vp->enabled) {
+		pr_warn("%s: Trying to disable VP for vdd_%s when it is already disabled\n",
+			__func__, voltdm->name);
+		return;
+	}
+
+	/* Disable VP */
+	vpconfig = voltdm->read(vp->vpconfig);
+	vpconfig &= ~vp->common->vpconfig_vpenable;
+	voltdm->write(vpconfig, vp->vpconfig);
+
+	/*
+	 * Wait for VP idle Typical latency is <2us. Maximum latency is ~100us
+	 */
+	omap_test_timeout((voltdm->read(vp->vstatus)),
+			  VP_IDLE_TIMEOUT, timeout);
+
+	if (timeout >= VP_IDLE_TIMEOUT)
+		pr_warn("%s: vdd_%s idle timedout\n", __func__, voltdm->name);
+
+	vp->enabled = false;
+
+	return;
+}