Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 628 insertions, 0 deletions

diff --git a/drivers/fsi/fsi-scom.c b/drivers/fsi/fsi-scom.c
new file mode 100644
index 0000000000..61dbda9dbe
--- /dev/null
+++ b/drivers/fsi/fsi-scom.c
@@ -0,0 +1,628 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SCOM FSI Client device driver
+ *
+ * Copyright (C) IBM Corporation 2016
+ */
+
+#include <linux/fsi.h>
+#include <linux/module.h>
+#include <linux/cdev.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/mod_devicetable.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+
+#include <uapi/linux/fsi.h>
+
+#define FSI_ENGID_SCOM		0x5
+
+/* SCOM engine register set */
+#define SCOM_DATA0_REG		0x00
+#define SCOM_DATA1_REG		0x04
+#define SCOM_CMD_REG		0x08
+#define SCOM_FSI2PIB_RESET_REG	0x18
+#define SCOM_STATUS_REG		0x1C /* Read */
+#define SCOM_PIB_RESET_REG	0x1C /* Write */
+
+/* Command register */
+#define SCOM_WRITE_CMD		0x80000000
+#define SCOM_READ_CMD		0x00000000
+
+/* Status register bits */
+#define SCOM_STATUS_ERR_SUMMARY		0x80000000
+#define SCOM_STATUS_PROTECTION		0x01000000
+#define SCOM_STATUS_PARITY		0x04000000
+#define SCOM_STATUS_PIB_ABORT		0x00100000
+#define SCOM_STATUS_PIB_RESP_MASK	0x00007000
+#define SCOM_STATUS_PIB_RESP_SHIFT	12
+
+#define SCOM_STATUS_FSI2PIB_ERROR	(SCOM_STATUS_PROTECTION |	\
+					 SCOM_STATUS_PARITY |		\
+					 SCOM_STATUS_PIB_ABORT)
+#define SCOM_STATUS_ANY_ERR		(SCOM_STATUS_FSI2PIB_ERROR |	\
+					 SCOM_STATUS_PIB_RESP_MASK)
+/* SCOM address encodings */
+#define XSCOM_ADDR_IND_FLAG		BIT_ULL(63)
+#define XSCOM_ADDR_INF_FORM1		BIT_ULL(60)
+
+/* SCOM indirect stuff */
+#define XSCOM_ADDR_DIRECT_PART		0x7fffffffull
+#define XSCOM_ADDR_INDIRECT_PART	0x000fffff00000000ull
+#define XSCOM_DATA_IND_READ		BIT_ULL(63)
+#define XSCOM_DATA_IND_COMPLETE		BIT_ULL(31)
+#define XSCOM_DATA_IND_ERR_MASK		0x70000000ull
+#define XSCOM_DATA_IND_ERR_SHIFT	28
+#define XSCOM_DATA_IND_DATA		0x0000ffffull
+#define XSCOM_DATA_IND_FORM1_DATA	0x000fffffffffffffull
+#define XSCOM_ADDR_FORM1_LOW		0x000ffffffffull
+#define XSCOM_ADDR_FORM1_HI		0xfff00000000ull
+#define XSCOM_ADDR_FORM1_HI_SHIFT	20
+
+/* Retries */
+#define SCOM_MAX_IND_RETRIES		10	/* Retries indirect not ready */
+
+struct scom_device {
+	struct list_head link;
+	struct fsi_device *fsi_dev;
+	struct device dev;
+	struct cdev cdev;
+	struct mutex lock;
+	bool dead;
+};
+
+static int __put_scom(struct scom_device *scom_dev, uint64_t value,
+		      uint32_t addr, uint32_t *status)
+{
+	__be32 data, raw_status;
+	int rc;
+
+	data = cpu_to_be32((value >> 32) & 0xffffffff);
+	rc = fsi_device_write(scom_dev->fsi_dev, SCOM_DATA0_REG, &data,
+				sizeof(uint32_t));
+	if (rc)
+		return rc;
+
+	data = cpu_to_be32(value & 0xffffffff);
+	rc = fsi_device_write(scom_dev->fsi_dev, SCOM_DATA1_REG, &data,
+				sizeof(uint32_t));
+	if (rc)
+		return rc;
+
+	data = cpu_to_be32(SCOM_WRITE_CMD | addr);
+	rc = fsi_device_write(scom_dev->fsi_dev, SCOM_CMD_REG, &data,
+				sizeof(uint32_t));
+	if (rc)
+		return rc;
+	rc = fsi_device_read(scom_dev->fsi_dev, SCOM_STATUS_REG, &raw_status,
+			     sizeof(uint32_t));
+	if (rc)
+		return rc;
+	*status = be32_to_cpu(raw_status);
+
+	return 0;
+}
+
+static int __get_scom(struct scom_device *scom_dev, uint64_t *value,
+		      uint32_t addr, uint32_t *status)
+{
+	__be32 data, raw_status;
+	int rc;
+
+
+	*value = 0ULL;
+	data = cpu_to_be32(SCOM_READ_CMD | addr);
+	rc = fsi_device_write(scom_dev->fsi_dev, SCOM_CMD_REG, &data,
+				sizeof(uint32_t));
+	if (rc)
+		return rc;
+	rc = fsi_device_read(scom_dev->fsi_dev, SCOM_STATUS_REG, &raw_status,
+			     sizeof(uint32_t));
+	if (rc)
+		return rc;
+
+	/*
+	 * Read the data registers even on error, so we don't have
+	 * to interpret the status register here.
+	 */
+	rc = fsi_device_read(scom_dev->fsi_dev, SCOM_DATA0_REG, &data,
+				sizeof(uint32_t));
+	if (rc)
+		return rc;
+	*value |= (uint64_t)be32_to_cpu(data) << 32;
+	rc = fsi_device_read(scom_dev->fsi_dev, SCOM_DATA1_REG, &data,
+				sizeof(uint32_t));
+	if (rc)
+		return rc;
+	*value |= be32_to_cpu(data);
+	*status = be32_to_cpu(raw_status);
+
+	return rc;
+}
+
+static int put_indirect_scom_form0(struct scom_device *scom, uint64_t value,
+				   uint64_t addr, uint32_t *status)
+{
+	uint64_t ind_data, ind_addr;
+	int rc, err;
+
+	if (value & ~XSCOM_DATA_IND_DATA)
+		return -EINVAL;
+
+	ind_addr = addr & XSCOM_ADDR_DIRECT_PART;
+	ind_data = (addr & XSCOM_ADDR_INDIRECT_PART) | value;
+	rc = __put_scom(scom, ind_data, ind_addr, status);
+	if (rc || (*status & SCOM_STATUS_ANY_ERR))
+		return rc;
+
+	rc = __get_scom(scom, &ind_data, addr, status);
+	if (rc || (*status & SCOM_STATUS_ANY_ERR))
+		return rc;
+
+	err = (ind_data & XSCOM_DATA_IND_ERR_MASK) >> XSCOM_DATA_IND_ERR_SHIFT;
+	*status = err << SCOM_STATUS_PIB_RESP_SHIFT;
+
+	return 0;
+}
+
+static int put_indirect_scom_form1(struct scom_device *scom, uint64_t value,
+				   uint64_t addr, uint32_t *status)
+{
+	uint64_t ind_data, ind_addr;
+
+	if (value & ~XSCOM_DATA_IND_FORM1_DATA)
+		return -EINVAL;
+
+	ind_addr = addr & XSCOM_ADDR_FORM1_LOW;
+	ind_data = value | (addr & XSCOM_ADDR_FORM1_HI) << XSCOM_ADDR_FORM1_HI_SHIFT;
+	return __put_scom(scom, ind_data, ind_addr, status);
+}
+
+static int get_indirect_scom_form0(struct scom_device *scom, uint64_t *value,
+				   uint64_t addr, uint32_t *status)
+{
+	uint64_t ind_data, ind_addr;
+	int rc, err;
+
+	ind_addr = addr & XSCOM_ADDR_DIRECT_PART;
+	ind_data = (addr & XSCOM_ADDR_INDIRECT_PART) | XSCOM_DATA_IND_READ;
+	rc = __put_scom(scom, ind_data, ind_addr, status);
+	if (rc || (*status & SCOM_STATUS_ANY_ERR))
+		return rc;
+
+	rc = __get_scom(scom, &ind_data, addr, status);
+	if (rc || (*status & SCOM_STATUS_ANY_ERR))
+		return rc;
+
+	err = (ind_data & XSCOM_DATA_IND_ERR_MASK) >> XSCOM_DATA_IND_ERR_SHIFT;
+	*status = err << SCOM_STATUS_PIB_RESP_SHIFT;
+	*value = ind_data & XSCOM_DATA_IND_DATA;
+
+	return 0;
+}
+
+static int raw_put_scom(struct scom_device *scom, uint64_t value,
+			uint64_t addr, uint32_t *status)
+{
+	if (addr & XSCOM_ADDR_IND_FLAG) {
+		if (addr & XSCOM_ADDR_INF_FORM1)
+			return put_indirect_scom_form1(scom, value, addr, status);
+		else
+			return put_indirect_scom_form0(scom, value, addr, status);
+	} else
+		return __put_scom(scom, value, addr, status);
+}
+
+static int raw_get_scom(struct scom_device *scom, uint64_t *value,
+			uint64_t addr, uint32_t *status)
+{
+	if (addr & XSCOM_ADDR_IND_FLAG) {
+		if (addr & XSCOM_ADDR_INF_FORM1)
+			return -ENXIO;
+		return get_indirect_scom_form0(scom, value, addr, status);
+	} else
+		return __get_scom(scom, value, addr, status);
+}
+
+static int handle_fsi2pib_status(struct scom_device *scom, uint32_t status)
+{
+	uint32_t dummy = -1;
+
+	if (status & SCOM_STATUS_FSI2PIB_ERROR)
+		fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, &dummy,
+				 sizeof(uint32_t));
+
+	if (status & SCOM_STATUS_PROTECTION)
+		return -EPERM;
+	if (status & SCOM_STATUS_PARITY)
+		return -EIO;
+
+	if (status & SCOM_STATUS_PIB_ABORT)
+		return -EBUSY;
+	return 0;
+}
+
+static int handle_pib_status(struct scom_device *scom, uint8_t status)
+{
+	uint32_t dummy = -1;
+
+	if (status == SCOM_PIB_SUCCESS)
+		return 0;
+	if (status == SCOM_PIB_BLOCKED)
+		return -EBUSY;
+
+	/* Reset the bridge */
+	fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, &dummy,
+			 sizeof(uint32_t));
+
+	switch(status) {
+	case SCOM_PIB_OFFLINE:
+		return -ENODEV;
+	case SCOM_PIB_BAD_ADDR:
+		return -ENXIO;
+	case SCOM_PIB_TIMEOUT:
+		return -ETIMEDOUT;
+	case SCOM_PIB_PARTIAL:
+	case SCOM_PIB_CLK_ERR:
+	case SCOM_PIB_PARITY_ERR:
+	default:
+		return -EIO;
+	}
+}
+
+static int put_scom(struct scom_device *scom, uint64_t value,
+		    uint64_t addr)
+{
+	uint32_t status;
+	int rc;
+
+	rc = raw_put_scom(scom, value, addr, &status);
+	if (rc)
+		return rc;
+
+	rc = handle_fsi2pib_status(scom, status);
+	if (rc)
+		return rc;
+
+	return handle_pib_status(scom,
+				 (status & SCOM_STATUS_PIB_RESP_MASK)
+				 >> SCOM_STATUS_PIB_RESP_SHIFT);
+}
+
+static int get_scom(struct scom_device *scom, uint64_t *value,
+		    uint64_t addr)
+{
+	uint32_t status;
+	int rc;
+
+	rc = raw_get_scom(scom, value, addr, &status);
+	if (rc)
+		return rc;
+
+	rc = handle_fsi2pib_status(scom, status);
+	if (rc)
+		return rc;
+
+	return handle_pib_status(scom,
+				 (status & SCOM_STATUS_PIB_RESP_MASK)
+				 >> SCOM_STATUS_PIB_RESP_SHIFT);
+}
+
+static ssize_t scom_read(struct file *filep, char __user *buf, size_t len,
+			 loff_t *offset)
+{
+	struct scom_device *scom = filep->private_data;
+	struct device *dev = &scom->fsi_dev->dev;
+	uint64_t val;
+	int rc;
+
+	if (len != sizeof(uint64_t))
+		return -EINVAL;
+
+	mutex_lock(&scom->lock);
+	if (scom->dead)
+		rc = -ENODEV;
+	else
+		rc = get_scom(scom, &val, *offset);
+	mutex_unlock(&scom->lock);
+	if (rc) {
+		dev_dbg(dev, "get_scom fail:%d\n", rc);
+		return rc;
+	}
+
+	rc = copy_to_user(buf, &val, len);
+	if (rc)
+		dev_dbg(dev, "copy to user failed:%d\n", rc);
+
+	return rc ? rc : len;
+}
+
+static ssize_t scom_write(struct file *filep, const char __user *buf,
+			  size_t len, loff_t *offset)
+{
+	int rc;
+	struct scom_device *scom = filep->private_data;
+	struct device *dev = &scom->fsi_dev->dev;
+	uint64_t val;
+
+	if (len != sizeof(uint64_t))
+		return -EINVAL;
+
+	rc = copy_from_user(&val, buf, len);
+	if (rc) {
+		dev_dbg(dev, "copy from user failed:%d\n", rc);
+		return -EINVAL;
+	}
+
+	mutex_lock(&scom->lock);
+	if (scom->dead)
+		rc = -ENODEV;
+	else
+		rc = put_scom(scom, val, *offset);
+	mutex_unlock(&scom->lock);
+	if (rc) {
+		dev_dbg(dev, "put_scom failed with:%d\n", rc);
+		return rc;
+	}
+
+	return len;
+}
+
+static loff_t scom_llseek(struct file *file, loff_t offset, int whence)
+{
+	switch (whence) {
+	case SEEK_CUR:
+		break;
+	case SEEK_SET:
+		file->f_pos = offset;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return offset;
+}
+
+static void raw_convert_status(struct scom_access *acc, uint32_t status)
+{
+	acc->pib_status = (status & SCOM_STATUS_PIB_RESP_MASK) >>
+		SCOM_STATUS_PIB_RESP_SHIFT;
+	acc->intf_errors = 0;
+
+	if (status & SCOM_STATUS_PROTECTION)
+		acc->intf_errors |= SCOM_INTF_ERR_PROTECTION;
+	else if (status & SCOM_STATUS_PARITY)
+		acc->intf_errors |= SCOM_INTF_ERR_PARITY;
+	else if (status & SCOM_STATUS_PIB_ABORT)
+		acc->intf_errors |= SCOM_INTF_ERR_ABORT;
+	else if (status & SCOM_STATUS_ERR_SUMMARY)
+		acc->intf_errors |= SCOM_INTF_ERR_UNKNOWN;
+}
+
+static int scom_raw_read(struct scom_device *scom, void __user *argp)
+{
+	struct scom_access acc;
+	uint32_t status;
+	int rc;
+
+	if (copy_from_user(&acc, argp, sizeof(struct scom_access)))
+		return -EFAULT;
+
+	rc = raw_get_scom(scom, &acc.data, acc.addr, &status);
+	if (rc)
+		return rc;
+	raw_convert_status(&acc, status);
+	if (copy_to_user(argp, &acc, sizeof(struct scom_access)))
+		return -EFAULT;
+	return 0;
+}
+
+static int scom_raw_write(struct scom_device *scom, void __user *argp)
+{
+	u64 prev_data, mask, data;
+	struct scom_access acc;
+	uint32_t status;
+	int rc;
+
+	if (copy_from_user(&acc, argp, sizeof(struct scom_access)))
+		return -EFAULT;
+
+	if (acc.mask) {
+		rc = raw_get_scom(scom, &prev_data, acc.addr, &status);
+		if (rc)
+			return rc;
+		if (status & SCOM_STATUS_ANY_ERR)
+			goto fail;
+		mask = acc.mask;
+	} else {
+		prev_data = mask = -1ull;
+	}
+	data = (prev_data & ~mask) | (acc.data & mask);
+	rc = raw_put_scom(scom, data, acc.addr, &status);
+	if (rc)
+		return rc;
+ fail:
+	raw_convert_status(&acc, status);
+	if (copy_to_user(argp, &acc, sizeof(struct scom_access)))
+		return -EFAULT;
+	return 0;
+}
+
+static int scom_reset(struct scom_device *scom, void __user *argp)
+{
+	uint32_t flags, dummy = -1;
+	int rc = 0;
+
+	if (get_user(flags, (__u32 __user *)argp))
+		return -EFAULT;
+	if (flags & SCOM_RESET_PIB)
+		rc = fsi_device_write(scom->fsi_dev, SCOM_PIB_RESET_REG, &dummy,
+				      sizeof(uint32_t));
+	if (!rc && (flags & (SCOM_RESET_PIB | SCOM_RESET_INTF)))
+		rc = fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, &dummy,
+				      sizeof(uint32_t));
+	return rc;
+}
+
+static int scom_check(struct scom_device *scom, void __user *argp)
+{
+	/* Still need to find out how to get "protected" */
+	return put_user(SCOM_CHECK_SUPPORTED, (__u32 __user *)argp);
+}
+
+static long scom_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct scom_device *scom = file->private_data;
+	void __user *argp = (void __user *)arg;
+	int rc = -ENOTTY;
+
+	mutex_lock(&scom->lock);
+	if (scom->dead) {
+		mutex_unlock(&scom->lock);
+		return -ENODEV;
+	}
+	switch(cmd) {
+	case FSI_SCOM_CHECK:
+		rc = scom_check(scom, argp);
+		break;
+	case FSI_SCOM_READ:
+		rc = scom_raw_read(scom, argp);
+		break;
+	case FSI_SCOM_WRITE:
+		rc = scom_raw_write(scom, argp);
+		break;
+	case FSI_SCOM_RESET:
+		rc = scom_reset(scom, argp);
+		break;
+	}
+	mutex_unlock(&scom->lock);
+	return rc;
+}
+
+static int scom_open(struct inode *inode, struct file *file)
+{
+	struct scom_device *scom = container_of(inode->i_cdev, struct scom_device, cdev);
+
+	file->private_data = scom;
+
+	return 0;
+}
+
+static const struct file_operations scom_fops = {
+	.owner		= THIS_MODULE,
+	.open		= scom_open,
+	.llseek		= scom_llseek,
+	.read		= scom_read,
+	.write		= scom_write,
+	.unlocked_ioctl	= scom_ioctl,
+};
+
+static void scom_free(struct device *dev)
+{
+	struct scom_device *scom = container_of(dev, struct scom_device, dev);
+
+	put_device(&scom->fsi_dev->dev);
+	kfree(scom);
+}
+
+static int scom_probe(struct device *dev)
+{
+	struct fsi_device *fsi_dev = to_fsi_dev(dev);
+	struct scom_device *scom;
+	int rc, didx;
+
+	scom = kzalloc(sizeof(*scom), GFP_KERNEL);
+	if (!scom)
+		return -ENOMEM;
+	dev_set_drvdata(dev, scom);
+	mutex_init(&scom->lock);
+
+	/* Grab a reference to the device (parent of our cdev), we'll drop it later */
+	if (!get_device(dev)) {
+		kfree(scom);
+		return -ENODEV;
+	}
+	scom->fsi_dev = fsi_dev;
+
+	/* Create chardev for userspace access */
+	scom->dev.type = &fsi_cdev_type;
+	scom->dev.parent = dev;
+	scom->dev.release = scom_free;
+	device_initialize(&scom->dev);
+
+	/* Allocate a minor in the FSI space */
+	rc = fsi_get_new_minor(fsi_dev, fsi_dev_scom, &scom->dev.devt, &didx);
+	if (rc)
+		goto err;
+
+	dev_set_name(&scom->dev, "scom%d", didx);
+	cdev_init(&scom->cdev, &scom_fops);
+	rc = cdev_device_add(&scom->cdev, &scom->dev);
+	if (rc) {
+		dev_err(dev, "Error %d creating char device %s\n",
+			rc, dev_name(&scom->dev));
+		goto err_free_minor;
+	}
+
+	return 0;
+ err_free_minor:
+	fsi_free_minor(scom->dev.devt);
+ err:
+	put_device(&scom->dev);
+	return rc;
+}
+
+static int scom_remove(struct device *dev)
+{
+	struct scom_device *scom = dev_get_drvdata(dev);
+
+	mutex_lock(&scom->lock);
+	scom->dead = true;
+	mutex_unlock(&scom->lock);
+	cdev_device_del(&scom->cdev, &scom->dev);
+	fsi_free_minor(scom->dev.devt);
+	put_device(&scom->dev);
+
+	return 0;
+}
+
+static const struct of_device_id scom_of_ids[] = {
+	{ .compatible = "ibm,fsi2pib" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, scom_of_ids);
+
+static const struct fsi_device_id scom_ids[] = {
+	{
+		.engine_type = FSI_ENGID_SCOM,
+		.version = FSI_VERSION_ANY,
+	},
+	{ 0 }
+};
+
+static struct fsi_driver scom_drv = {
+	.id_table = scom_ids,
+	.drv = {
+		.name = "scom",
+		.bus = &fsi_bus_type,
+		.of_match_table = scom_of_ids,
+		.probe = scom_probe,
+		.remove = scom_remove,
+	}
+};
+
+static int scom_init(void)
+{
+	return fsi_driver_register(&scom_drv);
+}
+
+static void scom_exit(void)
+{
+	fsi_driver_unregister(&scom_drv);
+}
+
+module_init(scom_init);
+module_exit(scom_exit);
+MODULE_LICENSE("GPL");