Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 346 insertions, 0 deletions

diff --git a/drivers/char/bsr.c b/drivers/char/bsr.c
new file mode 100644
index 000000000..98e9327bf
--- /dev/null
+++ b/drivers/char/bsr.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* IBM POWER Barrier Synchronization Register Driver
+ *
+ * Copyright IBM Corporation 2008
+ *
+ * Author: Sonny Rao <sonnyrao@us.ibm.com>
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/cdev.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <asm/io.h>
+
+/*
+ This driver exposes a special register which can be used for fast
+ synchronization across a large SMP machine.  The hardware is exposed
+ as an array of bytes where each process will write to one of the bytes to
+ indicate it has finished the current stage and this update is broadcast to
+ all processors without having to bounce a cacheline between them. In
+ POWER5 and POWER6 there is one of these registers per SMP,  but it is
+ presented in two forms; first, it is given as a whole and then as a number
+ of smaller registers which alias to parts of the single whole register.
+ This can potentially allow multiple groups of processes to each have their
+ own private synchronization device.
+
+ Note that this hardware *must* be written to using *only* single byte writes.
+ It may be read using 1, 2, 4, or 8 byte loads which must be aligned since
+ this region is treated as cache-inhibited  processes should also use a
+ full sync before and after writing to the BSR to ensure all stores and
+ the BSR update have made it to all chips in the system
+*/
+
+/* This is arbitrary number, up to Power6 it's been 17 or fewer  */
+#define BSR_MAX_DEVS (32)
+
+struct bsr_dev {
+	u64      bsr_addr;     /* Real address */
+	u64      bsr_len;      /* length of mem region we can map */
+	unsigned bsr_bytes;    /* size of the BSR reg itself */
+	unsigned bsr_stride;   /* interval at which BSR repeats in the page */
+	unsigned bsr_type;     /* maps to enum below */
+	unsigned bsr_num;      /* bsr id number for its type */
+	int      bsr_minor;
+
+	struct list_head bsr_list;
+
+	dev_t    bsr_dev;
+	struct cdev bsr_cdev;
+	struct device *bsr_device;
+	char     bsr_name[32];
+
+};
+
+static unsigned total_bsr_devs;
+static LIST_HEAD(bsr_devs);
+static int bsr_major;
+
+enum {
+	BSR_8    = 0,
+	BSR_16   = 1,
+	BSR_64   = 2,
+	BSR_128  = 3,
+	BSR_4096 = 4,
+	BSR_UNKNOWN = 5,
+	BSR_MAX  = 6,
+};
+
+static unsigned bsr_types[BSR_MAX];
+
+static ssize_t
+bsr_size_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bsr_dev *bsr_dev = dev_get_drvdata(dev);
+	return sprintf(buf, "%u\n", bsr_dev->bsr_bytes);
+}
+static DEVICE_ATTR_RO(bsr_size);
+
+static ssize_t
+bsr_stride_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bsr_dev *bsr_dev = dev_get_drvdata(dev);
+	return sprintf(buf, "%u\n", bsr_dev->bsr_stride);
+}
+static DEVICE_ATTR_RO(bsr_stride);
+
+static ssize_t
+bsr_length_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bsr_dev *bsr_dev = dev_get_drvdata(dev);
+	return sprintf(buf, "%llu\n", bsr_dev->bsr_len);
+}
+static DEVICE_ATTR_RO(bsr_length);
+
+static struct attribute *bsr_dev_attrs[] = {
+	&dev_attr_bsr_size.attr,
+	&dev_attr_bsr_stride.attr,
+	&dev_attr_bsr_length.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(bsr_dev);
+
+static const struct class bsr_class = {
+	.name		= "bsr",
+	.dev_groups	= bsr_dev_groups,
+};
+
+static int bsr_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	unsigned long size   = vma->vm_end - vma->vm_start;
+	struct bsr_dev *dev = filp->private_data;
+	int ret;
+
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	/* check for the case of a small BSR device and map one 4k page for it*/
+	if (dev->bsr_len < PAGE_SIZE && size == PAGE_SIZE)
+		ret = remap_4k_pfn(vma, vma->vm_start, dev->bsr_addr >> 12,
+				   vma->vm_page_prot);
+	else if (size <= dev->bsr_len)
+		ret = io_remap_pfn_range(vma, vma->vm_start,
+					 dev->bsr_addr >> PAGE_SHIFT,
+					 size, vma->vm_page_prot);
+	else
+		return -EINVAL;
+
+	if (ret)
+		return -EAGAIN;
+
+	return 0;
+}
+
+static int bsr_open(struct inode *inode, struct file *filp)
+{
+	struct cdev *cdev = inode->i_cdev;
+	struct bsr_dev *dev = container_of(cdev, struct bsr_dev, bsr_cdev);
+
+	filp->private_data = dev;
+	return 0;
+}
+
+static const struct file_operations bsr_fops = {
+	.owner = THIS_MODULE,
+	.mmap  = bsr_mmap,
+	.open  = bsr_open,
+	.llseek = noop_llseek,
+};
+
+static void bsr_cleanup_devs(void)
+{
+	struct bsr_dev *cur, *n;
+
+	list_for_each_entry_safe(cur, n, &bsr_devs, bsr_list) {
+		if (cur->bsr_device) {
+			cdev_del(&cur->bsr_cdev);
+			device_del(cur->bsr_device);
+		}
+		list_del(&cur->bsr_list);
+		kfree(cur);
+	}
+}
+
+static int bsr_add_node(struct device_node *bn)
+{
+	int bsr_stride_len, bsr_bytes_len, num_bsr_devs;
+	const u32 *bsr_stride;
+	const u32 *bsr_bytes;
+	unsigned i;
+	int ret = -ENODEV;
+
+	bsr_stride = of_get_property(bn, "ibm,lock-stride", &bsr_stride_len);
+	bsr_bytes  = of_get_property(bn, "ibm,#lock-bytes", &bsr_bytes_len);
+
+	if (!bsr_stride || !bsr_bytes ||
+	    (bsr_stride_len != bsr_bytes_len)) {
+		printk(KERN_ERR "bsr of-node has missing/incorrect property\n");
+		return ret;
+	}
+
+	num_bsr_devs = bsr_bytes_len / sizeof(u32);
+
+	for (i = 0 ; i < num_bsr_devs; i++) {
+		struct bsr_dev *cur = kzalloc_obj(struct bsr_dev);
+		struct resource res;
+		int result;
+
+		if (!cur) {
+			printk(KERN_ERR "Unable to alloc bsr dev\n");
+			ret = -ENOMEM;
+			goto out_err;
+		}
+
+		result = of_address_to_resource(bn, i, &res);
+		if (result < 0) {
+			printk(KERN_ERR "bsr of-node has invalid reg property, skipping\n");
+			kfree(cur);
+			continue;
+		}
+
+		cur->bsr_minor  = i + total_bsr_devs;
+		cur->bsr_addr   = res.start;
+		cur->bsr_len    = resource_size(&res);
+		cur->bsr_bytes  = bsr_bytes[i];
+		cur->bsr_stride = bsr_stride[i];
+		cur->bsr_dev    = MKDEV(bsr_major, i + total_bsr_devs);
+
+		/* if we have a bsr_len of > 4k and less then PAGE_SIZE (64k pages) */
+		/* we can only map 4k of it, so only advertise the 4k in sysfs */
+		if (cur->bsr_len > 4096 && cur->bsr_len < PAGE_SIZE)
+			cur->bsr_len = 4096;
+
+		switch(cur->bsr_bytes) {
+		case 8:
+			cur->bsr_type = BSR_8;
+			break;
+		case 16:
+			cur->bsr_type = BSR_16;
+			break;
+		case 64:
+			cur->bsr_type = BSR_64;
+			break;
+		case 128:
+			cur->bsr_type = BSR_128;
+			break;
+		case 4096:
+			cur->bsr_type = BSR_4096;
+			break;
+		default:
+			cur->bsr_type = BSR_UNKNOWN;
+		}
+
+		cur->bsr_num = bsr_types[cur->bsr_type];
+		snprintf(cur->bsr_name, 32, "bsr%d_%d",
+			 cur->bsr_bytes, cur->bsr_num);
+
+		cdev_init(&cur->bsr_cdev, &bsr_fops);
+		result = cdev_add(&cur->bsr_cdev, cur->bsr_dev, 1);
+		if (result) {
+			kfree(cur);
+			goto out_err;
+		}
+
+		cur->bsr_device = device_create(&bsr_class, NULL, cur->bsr_dev,
+						cur, "%s", cur->bsr_name);
+		if (IS_ERR(cur->bsr_device)) {
+			printk(KERN_ERR "device_create failed for %s\n",
+			       cur->bsr_name);
+			cdev_del(&cur->bsr_cdev);
+			kfree(cur);
+			goto out_err;
+		}
+
+		bsr_types[cur->bsr_type] = cur->bsr_num + 1;
+		list_add_tail(&cur->bsr_list, &bsr_devs);
+	}
+
+	total_bsr_devs += num_bsr_devs;
+
+	return 0;
+
+ out_err:
+
+	bsr_cleanup_devs();
+	return ret;
+}
+
+static int bsr_create_devs(struct device_node *bn)
+{
+	int ret;
+
+	while (bn) {
+		ret = bsr_add_node(bn);
+		if (ret) {
+			of_node_put(bn);
+			return ret;
+		}
+		bn = of_find_compatible_node(bn, NULL, "ibm,bsr");
+	}
+	return 0;
+}
+
+static int __init bsr_init(void)
+{
+	struct device_node *np;
+	dev_t bsr_dev;
+	int ret = -ENODEV;
+
+	np = of_find_compatible_node(NULL, NULL, "ibm,bsr");
+	if (!np)
+		goto out_err;
+
+	ret = class_register(&bsr_class);
+	if (ret)
+		goto out_err_1;
+
+	ret = alloc_chrdev_region(&bsr_dev, 0, BSR_MAX_DEVS, "bsr");
+	bsr_major = MAJOR(bsr_dev);
+	if (ret < 0) {
+		printk(KERN_ERR "alloc_chrdev_region() failed for bsr\n");
+		goto out_err_2;
+	}
+
+	ret = bsr_create_devs(np);
+	if (ret < 0) {
+		np = NULL;
+		goto out_err_3;
+	}
+
+	return 0;
+
+ out_err_3:
+	unregister_chrdev_region(bsr_dev, BSR_MAX_DEVS);
+
+ out_err_2:
+	class_unregister(&bsr_class);
+
+ out_err_1:
+	of_node_put(np);
+
+ out_err:
+
+	return ret;
+}
+
+static void __exit  bsr_exit(void)
+{
+
+	bsr_cleanup_devs();
+
+	class_unregister(&bsr_class);
+
+	if (bsr_major)
+		unregister_chrdev_region(MKDEV(bsr_major, 0), BSR_MAX_DEVS);
+}
+
+module_init(bsr_init);
+module_exit(bsr_exit);
+MODULE_DESCRIPTION("IBM POWER Barrier Synchronization Register Driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sonny Rao <sonnyrao@us.ibm.com>");