@@ -163,4 +163,15 @@ struct vas_window *vas_tx_win_open(int vasid, enum vas_cop_type cop,
*/
int vas_paste_crb(struct vas_window *win, int offset, bool re);
+/*
+ * Register / unregister coprocessor type to VAS API which will be exported
+ * to user space. Applications can use this API to open / close window
+ * which can be used to send / receive requests directly to cooprcessor.
+ *
+ * Only NX GZIP coprocessor type is supported now, but this API can be
+ * used for others in future.
+ */
+int vas_register_coproc_api(struct module *mod);
+void vas_unregister_coproc_api(void);
+
#endif /* __ASM_POWERPC_VAS_H */
@@ -17,7 +17,7 @@ obj-$(CONFIG_MEMORY_FAILURE) += opal-memory-errors.o
obj-$(CONFIG_OPAL_PRD) += opal-prd.o
obj-$(CONFIG_PERF_EVENTS) += opal-imc.o
obj-$(CONFIG_PPC_MEMTRACE) += memtrace.o
-obj-$(CONFIG_PPC_VAS) += vas.o vas-window.o vas-debug.o vas-fault.o
+obj-$(CONFIG_PPC_VAS) += vas.o vas-window.o vas-debug.o vas-fault.o vas-api.o
obj-$(CONFIG_OCXL_BASE) += ocxl.o
obj-$(CONFIG_SCOM_DEBUGFS) += opal-xscom.o
obj-$(CONFIG_PPC_SECURE_BOOT) += opal-secvar.o
new file mode 100644
@@ -0,0 +1,257 @@
+// 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.
+ */
+
+static char *coproc_dev_name = "nx-gzip";
+
+/*
+ * 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;
+} coproc_device;
+
+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)
+{
+ /*
+ * vas_window is allocated and assigned to fp->private_data
+ * in ioctl. Nothing to do here for NX GZIP.
+ */
+ 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 vas_window *txwin;
+ int rc, vasid;
+
+ /*
+ * One window for file descriptor
+ */
+ if (fp->private_data)
+ 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, VAS_COP_TYPE_GZIP);
+
+ 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, VAS_COP_TYPE_GZIP, &txattr);
+ if (IS_ERR(txwin)) {
+ pr_err("%s() vas_tx_win_open() failed, %ld\n", __func__,
+ PTR_ERR(txwin));
+ return PTR_ERR(txwin);
+ }
+
+ fp->private_data = txwin;
+
+ return 0;
+}
+
+static int coproc_release(struct inode *inode, struct file *fp)
+{
+ struct vas_window *txwin = fp->private_data;
+
+ if (txwin) {
+ vas_win_close(txwin);
+ 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 vas_window *txwin = fp->private_data;
+ unsigned long pfn;
+ u64 paste_addr;
+ pgprot_t prot;
+ int rc;
+
+ 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)
+{
+ int rc = -EINVAL;
+ dev_t devno;
+
+ rc = alloc_chrdev_region(&coproc_device.devt, 1, 1, coproc_dev_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", coproc_dev_name,
+ MAJOR(coproc_device.devt), MINOR(coproc_device.devt));
+
+ coproc_device.class = class_create(mod, coproc_dev_name);
+ if (IS_ERR(coproc_device.class)) {
+ rc = PTR_ERR(coproc_device.class);
+ pr_err("Unable to create %s class %d\n", coproc_dev_name, rc);
+ goto err_class;
+ }
+ coproc_device.class->devnode = coproc_devnode;
+
+ 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, coproc_dev_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);
@@ -26,7 +26,7 @@
* Compute the paste address region for the window @window using the
* ->paste_base_addr and ->paste_win_id_shift we got from device tree.
*/
-static void compute_paste_address(struct vas_window *window, u64 *addr, int *len)
+void vas_win_paste_addr(struct vas_window *window, u64 *addr, int *len)
{
int winid;
u64 base, shift;
@@ -80,7 +80,7 @@ static void *map_paste_region(struct vas_window *txwin)
goto free_name;
txwin->paste_addr_name = name;
- compute_paste_address(txwin, &start, &len);
+ vas_win_paste_addr(txwin, &start, &len);
if (!request_mem_region(start, len, name)) {
pr_devel("%s(): request_mem_region(0x%llx, %d) failed\n",
@@ -138,7 +138,7 @@ static void unmap_paste_region(struct vas_window *window)
u64 busaddr_start;
if (window->paste_kaddr) {
- compute_paste_address(window, &busaddr_start, &len);
+ vas_win_paste_addr(window, &busaddr_start, &len);
unmap_region(window->paste_kaddr, busaddr_start, len);
window->paste_kaddr = NULL;
kfree(window->paste_addr_name);
@@ -431,6 +431,8 @@ struct vas_winctx {
extern void vas_return_credit(struct vas_window *window, bool tx);
extern struct vas_window *vas_pswid_to_window(struct vas_instance *vinst,
uint32_t pswid);
+extern void vas_win_paste_addr(struct vas_window *window, u64 *addr,
+ int *len);
static inline int vas_window_pid(struct vas_window *window)
{