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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/powerpc/platforms/powernv/vas-api.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/platforms/powernv/vas-api.c')
-rw-r--r--arch/powerpc/platforms/powernv/vas-api.c278
1 files changed, 278 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/vas-api.c b/arch/powerpc/platforms/powernv/vas-api.c
new file mode 100644
index 000000000..98ed5d8c5
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-api.c
@@ -0,0 +1,278 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * VAS user space API for its accelerators (Only NX-GZIP is supported now)
+ * Copyright (C) 2019 Haren Myneni, IBM Corp
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <asm/vas.h>
+#include <uapi/asm/vas-api.h>
+#include "vas.h"
+
+/*
+ * The driver creates the device node that can be used as follows:
+ * For NX-GZIP
+ *
+ * fd = open("/dev/crypto/nx-gzip", O_RDWR);
+ * rc = ioctl(fd, VAS_TX_WIN_OPEN, &attr);
+ * paste_addr = mmap(NULL, PAGE_SIZE, prot, MAP_SHARED, fd, 0ULL).
+ * vas_copy(&crb, 0, 1);
+ * vas_paste(paste_addr, 0, 1);
+ * close(fd) or exit process to close window.
+ *
+ * where "vas_copy" and "vas_paste" are defined in copy-paste.h.
+ * copy/paste returns to the user space directly. So refer NX hardware
+ * documententation for exact copy/paste usage and completion / error
+ * conditions.
+ */
+
+/*
+ * Wrapper object for the nx-gzip device - there is just one instance of
+ * this node for the whole system.
+ */
+static struct coproc_dev {
+ struct cdev cdev;
+ struct device *device;
+ char *name;
+ dev_t devt;
+ struct class *class;
+ enum vas_cop_type cop_type;
+} coproc_device;
+
+struct coproc_instance {
+ struct coproc_dev *coproc;
+ struct vas_window *txwin;
+};
+
+static char *coproc_devnode(struct device *dev, umode_t *mode)
+{
+ return kasprintf(GFP_KERNEL, "crypto/%s", dev_name(dev));
+}
+
+static int coproc_open(struct inode *inode, struct file *fp)
+{
+ struct coproc_instance *cp_inst;
+
+ cp_inst = kzalloc(sizeof(*cp_inst), GFP_KERNEL);
+ if (!cp_inst)
+ return -ENOMEM;
+
+ cp_inst->coproc = container_of(inode->i_cdev, struct coproc_dev,
+ cdev);
+ fp->private_data = cp_inst;
+
+ return 0;
+}
+
+static int coproc_ioc_tx_win_open(struct file *fp, unsigned long arg)
+{
+ void __user *uptr = (void __user *)arg;
+ struct vas_tx_win_attr txattr = {};
+ struct vas_tx_win_open_attr uattr;
+ struct coproc_instance *cp_inst;
+ struct vas_window *txwin;
+ int rc, vasid;
+
+ cp_inst = fp->private_data;
+
+ /*
+ * One window for file descriptor
+ */
+ if (cp_inst->txwin)
+ return -EEXIST;
+
+ rc = copy_from_user(&uattr, uptr, sizeof(uattr));
+ if (rc) {
+ pr_err("%s(): copy_from_user() returns %d\n", __func__, rc);
+ return -EFAULT;
+ }
+
+ if (uattr.version != 1) {
+ pr_err("Invalid version\n");
+ return -EINVAL;
+ }
+
+ vasid = uattr.vas_id;
+
+ vas_init_tx_win_attr(&txattr, cp_inst->coproc->cop_type);
+
+ txattr.lpid = mfspr(SPRN_LPID);
+ txattr.pidr = mfspr(SPRN_PID);
+ txattr.user_win = true;
+ txattr.rsvd_txbuf_count = false;
+ txattr.pswid = false;
+
+ pr_devel("Pid %d: Opening txwin, PIDR %ld\n", txattr.pidr,
+ mfspr(SPRN_PID));
+
+ txwin = vas_tx_win_open(vasid, cp_inst->coproc->cop_type, &txattr);
+ if (IS_ERR(txwin)) {
+ pr_err("%s() vas_tx_win_open() failed, %ld\n", __func__,
+ PTR_ERR(txwin));
+ return PTR_ERR(txwin);
+ }
+
+ cp_inst->txwin = txwin;
+
+ return 0;
+}
+
+static int coproc_release(struct inode *inode, struct file *fp)
+{
+ struct coproc_instance *cp_inst = fp->private_data;
+
+ if (cp_inst->txwin) {
+ vas_win_close(cp_inst->txwin);
+ cp_inst->txwin = NULL;
+ }
+
+ kfree(cp_inst);
+ fp->private_data = NULL;
+
+ /*
+ * We don't know here if user has other receive windows
+ * open, so we can't really call clear_thread_tidr().
+ * So, once the process calls set_thread_tidr(), the
+ * TIDR value sticks around until process exits, resulting
+ * in an extra copy in restore_sprs().
+ */
+
+ return 0;
+}
+
+static int coproc_mmap(struct file *fp, struct vm_area_struct *vma)
+{
+ struct coproc_instance *cp_inst = fp->private_data;
+ struct vas_window *txwin;
+ unsigned long pfn;
+ u64 paste_addr;
+ pgprot_t prot;
+ int rc;
+
+ txwin = cp_inst->txwin;
+
+ if ((vma->vm_end - vma->vm_start) > PAGE_SIZE) {
+ pr_debug("%s(): size 0x%zx, PAGE_SIZE 0x%zx\n", __func__,
+ (vma->vm_end - vma->vm_start), PAGE_SIZE);
+ return -EINVAL;
+ }
+
+ /* Ensure instance has an open send window */
+ if (!txwin) {
+ pr_err("%s(): No send window open?\n", __func__);
+ return -EINVAL;
+ }
+
+ vas_win_paste_addr(txwin, &paste_addr, NULL);
+ pfn = paste_addr >> PAGE_SHIFT;
+
+ /* flags, page_prot from cxl_mmap(), except we want cachable */
+ vma->vm_flags |= VM_IO | VM_PFNMAP;
+ vma->vm_page_prot = pgprot_cached(vma->vm_page_prot);
+
+ prot = __pgprot(pgprot_val(vma->vm_page_prot) | _PAGE_DIRTY);
+
+ rc = remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
+ vma->vm_end - vma->vm_start, prot);
+
+ pr_devel("%s(): paste addr %llx at %lx, rc %d\n", __func__,
+ paste_addr, vma->vm_start, rc);
+
+ return rc;
+}
+
+static long coproc_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+ switch (cmd) {
+ case VAS_TX_WIN_OPEN:
+ return coproc_ioc_tx_win_open(fp, arg);
+ default:
+ return -EINVAL;
+ }
+}
+
+static struct file_operations coproc_fops = {
+ .open = coproc_open,
+ .release = coproc_release,
+ .mmap = coproc_mmap,
+ .unlocked_ioctl = coproc_ioctl,
+};
+
+/*
+ * Supporting only nx-gzip coprocessor type now, but this API code
+ * extended to other coprocessor types later.
+ */
+int vas_register_coproc_api(struct module *mod, enum vas_cop_type cop_type,
+ const char *name)
+{
+ int rc = -EINVAL;
+ dev_t devno;
+
+ rc = alloc_chrdev_region(&coproc_device.devt, 1, 1, name);
+ if (rc) {
+ pr_err("Unable to allocate coproc major number: %i\n", rc);
+ return rc;
+ }
+
+ pr_devel("%s device allocated, dev [%i,%i]\n", name,
+ MAJOR(coproc_device.devt), MINOR(coproc_device.devt));
+
+ coproc_device.class = class_create(mod, name);
+ if (IS_ERR(coproc_device.class)) {
+ rc = PTR_ERR(coproc_device.class);
+ pr_err("Unable to create %s class %d\n", name, rc);
+ goto err_class;
+ }
+ coproc_device.class->devnode = coproc_devnode;
+ coproc_device.cop_type = cop_type;
+
+ coproc_fops.owner = mod;
+ cdev_init(&coproc_device.cdev, &coproc_fops);
+
+ devno = MKDEV(MAJOR(coproc_device.devt), 0);
+ rc = cdev_add(&coproc_device.cdev, devno, 1);
+ if (rc) {
+ pr_err("cdev_add() failed %d\n", rc);
+ goto err_cdev;
+ }
+
+ coproc_device.device = device_create(coproc_device.class, NULL,
+ devno, NULL, name, MINOR(devno));
+ if (IS_ERR(coproc_device.device)) {
+ rc = PTR_ERR(coproc_device.device);
+ pr_err("Unable to create coproc-%d %d\n", MINOR(devno), rc);
+ goto err;
+ }
+
+ pr_devel("%s: Added dev [%d,%d]\n", __func__, MAJOR(devno),
+ MINOR(devno));
+
+ return 0;
+
+err:
+ cdev_del(&coproc_device.cdev);
+err_cdev:
+ class_destroy(coproc_device.class);
+err_class:
+ unregister_chrdev_region(coproc_device.devt, 1);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(vas_register_coproc_api);
+
+void vas_unregister_coproc_api(void)
+{
+ dev_t devno;
+
+ cdev_del(&coproc_device.cdev);
+ devno = MKDEV(MAJOR(coproc_device.devt), 0);
+ device_destroy(coproc_device.class, devno);
+
+ class_destroy(coproc_device.class);
+ unregister_chrdev_region(coproc_device.devt, 1);
+}
+EXPORT_SYMBOL_GPL(vas_unregister_coproc_api);