Add the Qualcomm PBS (Programmable Boot Sequencer) driver. The QCOM PBS
driver supports configuring software PBS trigger events through PBS RAM
on Qualcomm Technologies, Inc (QTI) PMICs.
Signed-off-by: Anjelique Melendez <quic_amelende@xxxxxxxxxxx>
---
drivers/soc/qcom/Kconfig | 9 ++
drivers/soc/qcom/Makefile | 1 +
drivers/soc/qcom/qcom-pbs.c | 243 ++++++++++++++++++++++++++++++
include/linux/soc/qcom/qcom-pbs.h | 30 ++++
4 files changed, 283 insertions(+)
create mode 100644 drivers/soc/qcom/qcom-pbs.c
create mode 100644 include/linux/soc/qcom/qcom-pbs.h
diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index b3634e10f6f5..52aa58b02e72 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -254,4 +254,13 @@ config QCOM_INLINE_CRYPTO_ENGINE
tristate
select QCOM_SCM
+config QCOM_PBS
+ tristate "PBS trigger support for Qualcomm Technologies, Inc. PMICS"
+ depends on SPMI
+ help
+ This driver supports configuring software programmable boot sequencer (PBS)
+ trigger event through PBS RAM on Qualcomm Technologies, Inc. PMICs.
+ This module provides the APIs to the client drivers that wants to send the
+ PBS trigger event to the PBS RAM.
+
endmenu
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index bbca2e1e55bb..49bb86b0fe33 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -32,3 +32,4 @@ obj-$(CONFIG_QCOM_KRYO_L2_ACCESSORS) += kryo-l2-accessors.o
obj-$(CONFIG_QCOM_ICC_BWMON) += icc-bwmon.o
qcom_ice-objs += ice.o
obj-$(CONFIG_QCOM_INLINE_CRYPTO_ENGINE) += qcom_ice.o
+obj-$(CONFIG_QCOM_PBS) += qcom-pbs.o
diff --git a/drivers/soc/qcom/qcom-pbs.c b/drivers/soc/qcom/qcom-pbs.c
new file mode 100644
index 000000000000..b49d14bb7d08
--- /dev/null
+++ b/drivers/soc/qcom/qcom-pbs.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <linux/spmi.h>
+#include <linux/soc/qcom/qcom-pbs.h>
+
+#define PBS_CLIENT_TRIG_CTL 0x42
+#define PBS_CLIENT_SW_TRIG_BIT BIT(7)
+#define PBS_CLIENT_SCRATCH1 0x50
+#define PBS_CLIENT_SCRATCH2 0x51
+#define PBS_CLIENT_SCRATCH2_ERROR 0xFF
+
+struct pbs_dev {
+ struct device *dev;
+ struct regmap *regmap;
+ struct mutex lock;
+ struct device_link *link;
+
+ u32 base;
+};
+
+static int qcom_pbs_wait_for_ack(struct pbs_dev *pbs, u8 bit_pos)
+{
+ int ret, retries = 2000, delay = 1100;
+ unsigned int val;
+
+ ret = regmap_read_poll_timeout(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
+ val, val & BIT(bit_pos), delay, delay * retries);
+
+ if (ret < 0) {
+ dev_err(pbs->dev, "Timeout for PBS ACK/NACK for bit %u\n", bit_pos);
+ return -ETIMEDOUT;
+ }
+
+ if (val == PBS_CLIENT_SCRATCH2_ERROR) {
+ ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
+ dev_err(pbs->dev, "NACK from PBS for bit %u\n", bit_pos);
+ return -EINVAL;
+ }
+
+ dev_dbg(pbs->dev, "PBS sequence for bit %u executed!\n", bit_pos);
+ return 0;
+}
+
+/**
+ * qcom_pbs_trigger_event() - Trigger the PBS RAM sequence
+ * @pbs: Pointer to PBS device
+ * @bitmap: bitmap
+ *
+ * This function is used to trigger the PBS RAM sequence to be
+ * executed by the client driver.
+ *
+ * The PBS trigger sequence involves
+ * 1. setting the PBS sequence bit in PBS_CLIENT_SCRATCH1
+ * 2. Initiating the SW PBS trigger
+ * 3. Checking the equivalent bit in PBS_CLIENT_SCRATCH2 for the
+ * completion of the sequence.
+ * 4. If PBS_CLIENT_SCRATCH2 == 0xFF, the PBS sequence failed to execute
+ *
+ * Returns: 0 on success, < 0 on failure
+ */
+int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap)
+{
+ unsigned int val;
+ u16 bit_pos;
+ int ret;
+
+ if (!bitmap) {
+ dev_err(pbs->dev, "Invalid bitmap passed by client\n");
+ return -EINVAL;
+ }
+
+ if (IS_ERR_OR_NULL(pbs))
+ return -EINVAL;
+
+ mutex_lock(&pbs->lock);
+ ret = regmap_read(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, &val);
+ if (ret < 0)
+ goto out;
+
+ if (val == PBS_CLIENT_SCRATCH2_ERROR) {
+ /* PBS error - clear SCRATCH2 register */
+ ret = regmap_write(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2, 0);
+ if (ret < 0)
+ goto out;
+ }
+
+ for (bit_pos = 0; bit_pos < 8; bit_pos++) {
+ if (!(bitmap & BIT(bit_pos)))
+ continue;
+
+ /* Clear the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
+ BIT(bit_pos), 0);
+ if (ret < 0)
+ goto error;
+
+ /* Set the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
+ BIT(bit_pos), BIT(bit_pos));
+ if (ret < 0)
+ goto error;
+
+ /* Initiate the SW trigger */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_TRIG_CTL,
+ PBS_CLIENT_SW_TRIG_BIT, PBS_CLIENT_SW_TRIG_BIT);
+ if (ret < 0)
+ goto error;
+
+ ret = qcom_pbs_wait_for_ack(pbs, bit_pos);
+ if (ret < 0)
+ goto error;
+
+ /* Clear the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1,
+ BIT(bit_pos), 0);
+ if (ret < 0)
+ goto error;
+
+ /* Clear the PBS sequence bit position */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH2,
+ BIT(bit_pos), 0);
+ if (ret < 0)
+ goto error;
+ }
+
+error:
+ /* Clear all the requested bitmap */
+ ret = regmap_update_bits(pbs->regmap, pbs->base + PBS_CLIENT_SCRATCH1, bitmap, 0);
+
+out:
+ mutex_unlock(&pbs->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(qcom_pbs_trigger_event);
+
+/**
+ * get_pbs_client_device() - Get the PBS device used by client
+ * @dev: Client device
+ *
+ * This function is used to get the PBS device that is being
+ * used by the client.
+ *
+ * Returns: pbs_dev on success, ERR_PTR on failure
+ */
+struct pbs_dev *get_pbs_client_device(struct device *dev)
+{
+ struct device_node *pbs_dev_node;
+ struct platform_device *pdev;
+ struct pbs_dev *pbs;
+
+ pbs_dev_node = of_parse_phandle(dev->of_node, "qcom,pbs", 0);
+ if (!pbs_dev_node) {
+ dev_err(dev, "Missing qcom,pbs property\n");
+ return ERR_PTR(-ENODEV);
+ }
+
+ pdev = of_find_device_by_node(pbs_dev_node);
+ if (!pdev) {
+ dev_err(dev, "Unable to find PBS dev_node\n");
+ pbs = ERR_PTR(-EPROBE_DEFER);
+ goto out;
+ }
+
+ pbs = platform_get_drvdata(pdev);
+ if (!pbs) {
+ dev_err(dev, "Cannot get pbs instance from %s\n", dev_name(&pdev->dev));
+ platform_device_put(pdev);
+ pbs = ERR_PTR(-EPROBE_DEFER);
+ goto out;
+ }
+
+ pbs->link = device_link_add(dev, &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER);
+ if (!pbs->link) {
+ dev_err(&pdev->dev, "Failed to create device link to consumer %s\n", dev_name(dev));
+ platform_device_put(pdev);
+ pbs = ERR_PTR(-EINVAL);
+ goto out;
+ }
+
+out:
+ of_node_put(pbs_dev_node);
+ return pbs;
+}
+EXPORT_SYMBOL_GPL(get_pbs_client_device);
+
+static int qcom_pbs_probe(struct platform_device *pdev)
+{
+ struct pbs_dev *pbs;
+ u32 val;
+ int ret;
+
+ pbs = devm_kzalloc(&pdev->dev, sizeof(*pbs), GFP_KERNEL);
+ if (!pbs)
+ return -ENOMEM;
+
+ pbs->dev = &pdev->dev;
+ pbs->regmap = dev_get_regmap(pbs->dev->parent, NULL);
+ if (!pbs->regmap) {
+ dev_err(pbs->dev, "Couldn't get parent's regmap\n");
+ return -EINVAL;
+ }
+
+ ret = device_property_read_u32(pbs->dev, "reg", &val);
+ if (ret < 0) {
+ dev_err(pbs->dev, "Couldn't find reg, ret = %d\n", ret);
+ return ret;
+ }
+ pbs->base = val;
+ mutex_init(&pbs->lock);
+
+ platform_set_drvdata(pdev, pbs);
+
+ return 0;
+}
+
+static const struct of_device_id qcom_pbs_match_table[] = {
+ { .compatible = "qcom,pbs" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, qcom_pbs_match_table);
+
+static struct platform_driver qcom_pbs_driver = {
+ .driver = {
+ .name = "qcom-pbs",
+ .of_match_table = qcom_pbs_match_table,
+ },
+ .probe = qcom_pbs_probe,
+};
+module_platform_driver(qcom_pbs_driver)
+
+MODULE_DESCRIPTION("QCOM PBS DRIVER");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/soc/qcom/qcom-pbs.h b/include/linux/soc/qcom/qcom-pbs.h
new file mode 100644
index 000000000000..8a46209ccf13
--- /dev/null
+++ b/include/linux/soc/qcom/qcom-pbs.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef _QCOM_PBS_H
+#define _QCOM_PBS_H
+
+#include <linux/errno.h>
+#include <linux/types.h>
+
+struct device_node;
+struct pbs_dev;
+
+#if IS_ENABLED(CONFIG_QCOM_PBS)
+int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap);
+struct pbs_dev *get_pbs_client_device(struct device *client_dev);
+#else
+static inline int qcom_pbs_trigger_event(struct pbs_dev *pbs, u8 bitmap)
+{
+ return -ENODEV;
+}
+
+static inline struct pbs_dev *get_pbs_client_device(struct device *client_dev)
+{
+ return ERR_PTR(-ENODEV);
+}
+#endif
+
+#endif
--
2.41.0
