1 files changed, 272 insertions, 0 deletions

diff --git a/drivers/hwtracing/coresight/coresight-config.c b/drivers/hwtracing/coresight/coresight-config.c
new file mode 100644
index 000000000000..4723bf7402a2
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-config.c
@@ -0,0 +1,272 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(C) 2020 Linaro Limited. All rights reserved.
+ * Author: Mike Leach <mike.leach@linaro.org>
+ */
+
+#include <linux/sysfs.h>
+#include "coresight-config.h"
+#include "coresight-priv.h"
+
+/*
+ * This provides a set of generic functions that operate on configurations
+ * and features to manage the handling of parameters, the programming and
+ * saving of registers used by features on devices.
+ */
+
+/*
+ * Write the value held in the register structure into the driver internal memory
+ * location.
+ */
+static void cscfg_set_reg(struct cscfg_regval_csdev *reg_csdev)
+{
+	u32 *p_val32 = (u32 *)reg_csdev->driver_regval;
+	u32 tmp32 = reg_csdev->reg_desc.val32;
+
+	if (reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_64BIT) {
+		*((u64 *)reg_csdev->driver_regval) = reg_csdev->reg_desc.val64;
+		return;
+	}
+
+	if (reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_MASK) {
+		tmp32 = *p_val32;
+		tmp32 &= ~reg_csdev->reg_desc.mask32;
+		tmp32 |= reg_csdev->reg_desc.val32 & reg_csdev->reg_desc.mask32;
+	}
+	*p_val32 = tmp32;
+}
+
+/*
+ * Read the driver value into the reg if this is marked as one we want to save.
+ */
+static void cscfg_save_reg(struct cscfg_regval_csdev *reg_csdev)
+{
+	if (!(reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_SAVE))
+		return;
+	if (reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_64BIT)
+		reg_csdev->reg_desc.val64 = *(u64 *)(reg_csdev->driver_regval);
+	else
+		reg_csdev->reg_desc.val32 = *(u32 *)(reg_csdev->driver_regval);
+}
+
+/*
+ * Some register values are set from parameters. Initialise these registers
+ * from the current parameter values.
+ */
+static void cscfg_init_reg_param(struct cscfg_feature_csdev *feat_csdev,
+				 struct cscfg_regval_desc *reg_desc,
+				 struct cscfg_regval_csdev *reg_csdev)
+{
+	struct cscfg_parameter_csdev *param_csdev;
+
+	/* for param, load routines have validated the index */
+	param_csdev = &feat_csdev->params_csdev[reg_desc->param_idx];
+	param_csdev->reg_csdev = reg_csdev;
+	param_csdev->val64 = reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_64BIT;
+
+	if (param_csdev->val64)
+		reg_csdev->reg_desc.val64 = param_csdev->current_value;
+	else
+		reg_csdev->reg_desc.val32 = (u32)param_csdev->current_value;
+}
+
+/* set values into the driver locations referenced in cscfg_reg_csdev */
+static int cscfg_set_on_enable(struct cscfg_feature_csdev *feat_csdev)
+{
+	unsigned long flags;
+	int i;
+
+	spin_lock_irqsave(feat_csdev->drv_spinlock, flags);
+	for (i = 0; i < feat_csdev->nr_regs; i++)
+		cscfg_set_reg(&feat_csdev->regs_csdev[i]);
+	spin_unlock_irqrestore(feat_csdev->drv_spinlock, flags);
+	dev_dbg(&feat_csdev->csdev->dev, "Feature %s: %s",
+		feat_csdev->feat_desc->name, "set on enable");
+	return 0;
+}
+
+/* copy back values from the driver locations referenced in cscfg_reg_csdev */
+static void cscfg_save_on_disable(struct cscfg_feature_csdev *feat_csdev)
+{
+	unsigned long flags;
+	int i;
+
+	spin_lock_irqsave(feat_csdev->drv_spinlock, flags);
+	for (i = 0; i < feat_csdev->nr_regs; i++)
+		cscfg_save_reg(&feat_csdev->regs_csdev[i]);
+	spin_unlock_irqrestore(feat_csdev->drv_spinlock, flags);
+	dev_dbg(&feat_csdev->csdev->dev, "Feature %s: %s",
+		feat_csdev->feat_desc->name, "save on disable");
+}
+
+/* default reset - restore default values */
+void cscfg_reset_feat(struct cscfg_feature_csdev *feat_csdev)
+{
+	struct cscfg_regval_desc *reg_desc;
+	struct cscfg_regval_csdev *reg_csdev;
+	int i;
+
+	/*
+	 * set the default values for all parameters and regs from the
+	 * relevant static descriptors.
+	 */
+	for (i = 0; i < feat_csdev->nr_params; i++)
+		feat_csdev->params_csdev[i].current_value =
+			feat_csdev->feat_desc->params_desc[i].value;
+
+	for (i = 0; i < feat_csdev->nr_regs; i++) {
+		reg_desc = &feat_csdev->feat_desc->regs_desc[i];
+		reg_csdev = &feat_csdev->regs_csdev[i];
+		reg_csdev->reg_desc.type = reg_desc->type;
+
+		/* check if reg set from a parameter otherwise desc default */
+		if (reg_desc->type & CS_CFG_REG_TYPE_VAL_PARAM)
+			cscfg_init_reg_param(feat_csdev, reg_desc, reg_csdev);
+		else
+			/*
+			 * for normal values the union between val64 & val32 + mask32
+			 * allows us to init using the 64 bit value
+			 */
+			reg_csdev->reg_desc.val64 = reg_desc->val64;
+	}
+}
+
+/*
+ * For the selected presets, we set the register associated with the parameter, to
+ * the value of the preset index associated with the parameter.
+ */
+static int cscfg_update_presets(struct cscfg_config_csdev *config_csdev, int preset)
+{
+	int i, j, val_idx = 0, nr_cfg_params;
+	struct cscfg_parameter_csdev *param_csdev;
+	struct cscfg_feature_csdev *feat_csdev;
+	const struct cscfg_config_desc *config_desc = config_csdev->config_desc;
+	const char *name;
+	const u64 *preset_base;
+	u64 val;
+
+	/* preset in range 1 to nr_presets */
+	if (preset < 1 || preset > config_desc->nr_presets)
+		return -EINVAL;
+	/*
+	 * Go through the array of features, assigning preset values to
+	 * feature parameters in the order they appear.
+	 * There should be precisely the same number of preset values as the
+	 * sum of number of parameters over all the features - but we will
+	 * ensure there is no overrun.
+	 */
+	nr_cfg_params = config_desc->nr_total_params;
+	preset_base = &config_desc->presets[(preset - 1) * nr_cfg_params];
+	for (i = 0; i < config_csdev->nr_feat; i++) {
+		feat_csdev = config_csdev->feats_csdev[i];
+		if (!feat_csdev->nr_params)
+			continue;
+
+		for (j = 0; j < feat_csdev->nr_params; j++) {
+			param_csdev = &feat_csdev->params_csdev[j];
+			name = feat_csdev->feat_desc->params_desc[j].name;
+			val = preset_base[val_idx++];
+			if (param_csdev->val64) {
+				dev_dbg(&config_csdev->csdev->dev,
+					"set param %s (%lld)", name, val);
+				param_csdev->reg_csdev->reg_desc.val64 = val;
+			} else {
+				param_csdev->reg_csdev->reg_desc.val32 = (u32)val;
+				dev_dbg(&config_csdev->csdev->dev,
+					"set param %s (%d)", name, (u32)val);
+			}
+		}
+
+		/* exit early if all params filled */
+		if (val_idx >= nr_cfg_params)
+			break;
+	}
+	return 0;
+}
+
+/*
+ * if we are not using a preset, then need to update the feature params
+ * with current values. This sets the register associated with the parameter
+ * with the current value of that parameter.
+ */
+static int cscfg_update_curr_params(struct cscfg_config_csdev *config_csdev)
+{
+	int i, j;
+	struct cscfg_feature_csdev *feat_csdev;
+	struct cscfg_parameter_csdev *param_csdev;
+	const char *name;
+	u64 val;
+
+	for (i = 0; i < config_csdev->nr_feat; i++) {
+		feat_csdev = config_csdev->feats_csdev[i];
+		if (!feat_csdev->nr_params)
+			continue;
+		for (j = 0; j < feat_csdev->nr_params; j++) {
+			param_csdev = &feat_csdev->params_csdev[j];
+			name = feat_csdev->feat_desc->params_desc[j].name;
+			val = param_csdev->current_value;
+			if (param_csdev->val64) {
+				dev_dbg(&config_csdev->csdev->dev,
+					"set param %s (%lld)", name, val);
+				param_csdev->reg_csdev->reg_desc.val64 = val;
+			} else {
+				param_csdev->reg_csdev->reg_desc.val32 = (u32)val;
+				dev_dbg(&config_csdev->csdev->dev,
+					"set param %s (%d)", name, (u32)val);
+			}
+		}
+	}
+	return 0;
+}
+
+/*
+ * Configuration values will be programmed into the driver locations if enabling, or read
+ * from relevant locations on disable.
+ */
+static int cscfg_prog_config(struct cscfg_config_csdev *config_csdev, bool enable)
+{
+	int i, err = 0;
+	struct cscfg_feature_csdev *feat_csdev;
+	struct coresight_device *csdev;
+
+	for (i = 0; i < config_csdev->nr_feat; i++) {
+		feat_csdev = config_csdev->feats_csdev[i];
+		csdev = feat_csdev->csdev;
+		dev_dbg(&csdev->dev, "cfg %s;  %s feature:%s", config_csdev->config_desc->name,
+			enable ? "enable" : "disable", feat_csdev->feat_desc->name);
+
+		if (enable)
+			err = cscfg_set_on_enable(feat_csdev);
+		else
+			cscfg_save_on_disable(feat_csdev);
+
+		if (err)
+			break;
+	}
+	return err;
+}
+
+/*
+ * Enable configuration for the device. Will result in the internal driver data
+ * being updated ready for programming into the device.
+ *
+ * @config_csdev:	config_csdev to set.
+ * @preset:		preset values to use - 0 for default.
+ */
+int cscfg_csdev_enable_config(struct cscfg_config_csdev *config_csdev, int preset)
+{
+	int err = 0;
+
+	if (preset)
+		err = cscfg_update_presets(config_csdev, preset);
+	else
+		err = cscfg_update_curr_params(config_csdev);
+	if (!err)
+		err = cscfg_prog_config(config_csdev, true);
+	return err;
+}
+
+void cscfg_csdev_disable_config(struct cscfg_config_csdev *config_csdev)
+{
+	cscfg_prog_config(config_csdev, false);
+}