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path: root/drivers/crypto/nx/nx-842-powernv.c
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Diffstat (limited to 'drivers/crypto/nx/nx-842-powernv.c')
-rw-r--r--drivers/crypto/nx/nx-842-powernv.c637
1 files changed, 637 insertions, 0 deletions
diff --git a/drivers/crypto/nx/nx-842-powernv.c b/drivers/crypto/nx/nx-842-powernv.c
new file mode 100644
index 000000000000..33b3b0abf4ae
--- /dev/null
+++ b/drivers/crypto/nx/nx-842-powernv.c
@@ -0,0 +1,637 @@
+/*
+ * Driver for IBM PowerNV 842 compression accelerator
+ *
+ * Copyright (C) 2015 Dan Streetman, IBM Corp
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "nx-842.h"
+
+#include <linux/timer.h>
+
+#include <asm/prom.h>
+#include <asm/icswx.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
+MODULE_DESCRIPTION("842 H/W Compression driver for IBM PowerNV processors");
+
+#define WORKMEM_ALIGN (CRB_ALIGN)
+#define CSB_WAIT_MAX (5000) /* ms */
+
+struct nx842_workmem {
+ /* Below fields must be properly aligned */
+ struct coprocessor_request_block crb; /* CRB_ALIGN align */
+ struct data_descriptor_entry ddl_in[DDL_LEN_MAX]; /* DDE_ALIGN align */
+ struct data_descriptor_entry ddl_out[DDL_LEN_MAX]; /* DDE_ALIGN align */
+ /* Above fields must be properly aligned */
+
+ ktime_t start;
+
+ char padding[WORKMEM_ALIGN]; /* unused, to allow alignment */
+} __packed __aligned(WORKMEM_ALIGN);
+
+struct nx842_coproc {
+ unsigned int chip_id;
+ unsigned int ct;
+ unsigned int ci;
+ struct list_head list;
+};
+
+/* no cpu hotplug on powernv, so this list never changes after init */
+static LIST_HEAD(nx842_coprocs);
+static unsigned int nx842_ct;
+
+/**
+ * setup_indirect_dde - Setup an indirect DDE
+ *
+ * The DDE is setup with the the DDE count, byte count, and address of
+ * first direct DDE in the list.
+ */
+static void setup_indirect_dde(struct data_descriptor_entry *dde,
+ struct data_descriptor_entry *ddl,
+ unsigned int dde_count, unsigned int byte_count)
+{
+ dde->flags = 0;
+ dde->count = dde_count;
+ dde->index = 0;
+ dde->length = cpu_to_be32(byte_count);
+ dde->address = cpu_to_be64(nx842_get_pa(ddl));
+}
+
+/**
+ * setup_direct_dde - Setup single DDE from buffer
+ *
+ * The DDE is setup with the buffer and length. The buffer must be properly
+ * aligned. The used length is returned.
+ * Returns:
+ * N Successfully set up DDE with N bytes
+ */
+static unsigned int setup_direct_dde(struct data_descriptor_entry *dde,
+ unsigned long pa, unsigned int len)
+{
+ unsigned int l = min_t(unsigned int, len, LEN_ON_PAGE(pa));
+
+ dde->flags = 0;
+ dde->count = 0;
+ dde->index = 0;
+ dde->length = cpu_to_be32(l);
+ dde->address = cpu_to_be64(pa);
+
+ return l;
+}
+
+/**
+ * setup_ddl - Setup DDL from buffer
+ *
+ * Returns:
+ * 0 Successfully set up DDL
+ */
+static int setup_ddl(struct data_descriptor_entry *dde,
+ struct data_descriptor_entry *ddl,
+ unsigned char *buf, unsigned int len,
+ bool in)
+{
+ unsigned long pa = nx842_get_pa(buf);
+ int i, ret, total_len = len;
+
+ if (!IS_ALIGNED(pa, DDE_BUFFER_ALIGN)) {
+ pr_debug("%s buffer pa 0x%lx not 0x%x-byte aligned\n",
+ in ? "input" : "output", pa, DDE_BUFFER_ALIGN);
+ return -EINVAL;
+ }
+
+ /* only need to check last mult; since buffer must be
+ * DDE_BUFFER_ALIGN aligned, and that is a multiple of
+ * DDE_BUFFER_SIZE_MULT, and pre-last page DDE buffers
+ * are guaranteed a multiple of DDE_BUFFER_SIZE_MULT.
+ */
+ if (len % DDE_BUFFER_LAST_MULT) {
+ pr_debug("%s buffer len 0x%x not a multiple of 0x%x\n",
+ in ? "input" : "output", len, DDE_BUFFER_LAST_MULT);
+ if (in)
+ return -EINVAL;
+ len = round_down(len, DDE_BUFFER_LAST_MULT);
+ }
+
+ /* use a single direct DDE */
+ if (len <= LEN_ON_PAGE(pa)) {
+ ret = setup_direct_dde(dde, pa, len);
+ WARN_ON(ret < len);
+ return 0;
+ }
+
+ /* use the DDL */
+ for (i = 0; i < DDL_LEN_MAX && len > 0; i++) {
+ ret = setup_direct_dde(&ddl[i], pa, len);
+ buf += ret;
+ len -= ret;
+ pa = nx842_get_pa(buf);
+ }
+
+ if (len > 0) {
+ pr_debug("0x%x total %s bytes 0x%x too many for DDL.\n",
+ total_len, in ? "input" : "output", len);
+ if (in)
+ return -EMSGSIZE;
+ total_len -= len;
+ }
+ setup_indirect_dde(dde, ddl, i, total_len);
+
+ return 0;
+}
+
+#define CSB_ERR(csb, msg, ...) \
+ pr_err("ERROR: " msg " : %02x %02x %02x %02x %08x\n", \
+ ##__VA_ARGS__, (csb)->flags, \
+ (csb)->cs, (csb)->cc, (csb)->ce, \
+ be32_to_cpu((csb)->count))
+
+#define CSB_ERR_ADDR(csb, msg, ...) \
+ CSB_ERR(csb, msg " at %lx", ##__VA_ARGS__, \
+ (unsigned long)be64_to_cpu((csb)->address))
+
+/**
+ * wait_for_csb
+ */
+static int wait_for_csb(struct nx842_workmem *wmem,
+ struct coprocessor_status_block *csb)
+{
+ ktime_t start = wmem->start, now = ktime_get();
+ ktime_t timeout = ktime_add_ms(start, CSB_WAIT_MAX);
+
+ while (!(ACCESS_ONCE(csb->flags) & CSB_V)) {
+ cpu_relax();
+ now = ktime_get();
+ if (ktime_after(now, timeout))
+ break;
+ }
+
+ /* hw has updated csb and output buffer */
+ barrier();
+
+ /* check CSB flags */
+ if (!(csb->flags & CSB_V)) {
+ CSB_ERR(csb, "CSB still not valid after %ld us, giving up",
+ (long)ktime_us_delta(now, start));
+ return -ETIMEDOUT;
+ }
+ if (csb->flags & CSB_F) {
+ CSB_ERR(csb, "Invalid CSB format");
+ return -EPROTO;
+ }
+ if (csb->flags & CSB_CH) {
+ CSB_ERR(csb, "Invalid CSB chaining state");
+ return -EPROTO;
+ }
+
+ /* verify CSB completion sequence is 0 */
+ if (csb->cs) {
+ CSB_ERR(csb, "Invalid CSB completion sequence");
+ return -EPROTO;
+ }
+
+ /* check CSB Completion Code */
+ switch (csb->cc) {
+ /* no error */
+ case CSB_CC_SUCCESS:
+ break;
+ case CSB_CC_TPBC_GT_SPBC:
+ /* not an error, but the compressed data is
+ * larger than the uncompressed data :(
+ */
+ break;
+
+ /* input data errors */
+ case CSB_CC_OPERAND_OVERLAP:
+ /* input and output buffers overlap */
+ CSB_ERR(csb, "Operand Overlap error");
+ return -EINVAL;
+ case CSB_CC_INVALID_OPERAND:
+ CSB_ERR(csb, "Invalid operand");
+ return -EINVAL;
+ case CSB_CC_NOSPC:
+ /* output buffer too small */
+ return -ENOSPC;
+ case CSB_CC_ABORT:
+ CSB_ERR(csb, "Function aborted");
+ return -EINTR;
+ case CSB_CC_CRC_MISMATCH:
+ CSB_ERR(csb, "CRC mismatch");
+ return -EINVAL;
+ case CSB_CC_TEMPL_INVALID:
+ CSB_ERR(csb, "Compressed data template invalid");
+ return -EINVAL;
+ case CSB_CC_TEMPL_OVERFLOW:
+ CSB_ERR(csb, "Compressed data template shows data past end");
+ return -EINVAL;
+
+ /* these should not happen */
+ case CSB_CC_INVALID_ALIGN:
+ /* setup_ddl should have detected this */
+ CSB_ERR_ADDR(csb, "Invalid alignment");
+ return -EINVAL;
+ case CSB_CC_DATA_LENGTH:
+ /* setup_ddl should have detected this */
+ CSB_ERR(csb, "Invalid data length");
+ return -EINVAL;
+ case CSB_CC_WR_TRANSLATION:
+ case CSB_CC_TRANSLATION:
+ case CSB_CC_TRANSLATION_DUP1:
+ case CSB_CC_TRANSLATION_DUP2:
+ case CSB_CC_TRANSLATION_DUP3:
+ case CSB_CC_TRANSLATION_DUP4:
+ case CSB_CC_TRANSLATION_DUP5:
+ case CSB_CC_TRANSLATION_DUP6:
+ /* should not happen, we use physical addrs */
+ CSB_ERR_ADDR(csb, "Translation error");
+ return -EPROTO;
+ case CSB_CC_WR_PROTECTION:
+ case CSB_CC_PROTECTION:
+ case CSB_CC_PROTECTION_DUP1:
+ case CSB_CC_PROTECTION_DUP2:
+ case CSB_CC_PROTECTION_DUP3:
+ case CSB_CC_PROTECTION_DUP4:
+ case CSB_CC_PROTECTION_DUP5:
+ case CSB_CC_PROTECTION_DUP6:
+ /* should not happen, we use physical addrs */
+ CSB_ERR_ADDR(csb, "Protection error");
+ return -EPROTO;
+ case CSB_CC_PRIVILEGE:
+ /* shouldn't happen, we're in HYP mode */
+ CSB_ERR(csb, "Insufficient Privilege error");
+ return -EPROTO;
+ case CSB_CC_EXCESSIVE_DDE:
+ /* shouldn't happen, setup_ddl doesn't use many dde's */
+ CSB_ERR(csb, "Too many DDEs in DDL");
+ return -EINVAL;
+ case CSB_CC_TRANSPORT:
+ /* shouldn't happen, we setup CRB correctly */
+ CSB_ERR(csb, "Invalid CRB");
+ return -EINVAL;
+ case CSB_CC_SEGMENTED_DDL:
+ /* shouldn't happen, setup_ddl creates DDL right */
+ CSB_ERR(csb, "Segmented DDL error");
+ return -EINVAL;
+ case CSB_CC_DDE_OVERFLOW:
+ /* shouldn't happen, setup_ddl creates DDL right */
+ CSB_ERR(csb, "DDE overflow error");
+ return -EINVAL;
+ case CSB_CC_SESSION:
+ /* should not happen with ICSWX */
+ CSB_ERR(csb, "Session violation error");
+ return -EPROTO;
+ case CSB_CC_CHAIN:
+ /* should not happen, we don't use chained CRBs */
+ CSB_ERR(csb, "Chained CRB error");
+ return -EPROTO;
+ case CSB_CC_SEQUENCE:
+ /* should not happen, we don't use chained CRBs */
+ CSB_ERR(csb, "CRB seqeunce number error");
+ return -EPROTO;
+ case CSB_CC_UNKNOWN_CODE:
+ CSB_ERR(csb, "Unknown subfunction code");
+ return -EPROTO;
+
+ /* hardware errors */
+ case CSB_CC_RD_EXTERNAL:
+ case CSB_CC_RD_EXTERNAL_DUP1:
+ case CSB_CC_RD_EXTERNAL_DUP2:
+ case CSB_CC_RD_EXTERNAL_DUP3:
+ CSB_ERR_ADDR(csb, "Read error outside coprocessor");
+ return -EPROTO;
+ case CSB_CC_WR_EXTERNAL:
+ CSB_ERR_ADDR(csb, "Write error outside coprocessor");
+ return -EPROTO;
+ case CSB_CC_INTERNAL:
+ CSB_ERR(csb, "Internal error in coprocessor");
+ return -EPROTO;
+ case CSB_CC_PROVISION:
+ CSB_ERR(csb, "Storage provision error");
+ return -EPROTO;
+ case CSB_CC_HW:
+ CSB_ERR(csb, "Correctable hardware error");
+ return -EPROTO;
+
+ default:
+ CSB_ERR(csb, "Invalid CC %d", csb->cc);
+ return -EPROTO;
+ }
+
+ /* check Completion Extension state */
+ if (csb->ce & CSB_CE_TERMINATION) {
+ CSB_ERR(csb, "CSB request was terminated");
+ return -EPROTO;
+ }
+ if (csb->ce & CSB_CE_INCOMPLETE) {
+ CSB_ERR(csb, "CSB request not complete");
+ return -EPROTO;
+ }
+ if (!(csb->ce & CSB_CE_TPBC)) {
+ CSB_ERR(csb, "TPBC not provided, unknown target length");
+ return -EPROTO;
+ }
+
+ /* successful completion */
+ pr_debug_ratelimited("Processed %u bytes in %lu us\n", csb->count,
+ (unsigned long)ktime_us_delta(now, start));
+
+ return 0;
+}
+
+/**
+ * nx842_powernv_function - compress/decompress data using the 842 algorithm
+ *
+ * (De)compression provided by the NX842 coprocessor on IBM PowerNV systems.
+ * This compresses or decompresses the provided input buffer into the provided
+ * output buffer.
+ *
+ * Upon return from this function @outlen contains the length of the
+ * output data. If there is an error then @outlen will be 0 and an
+ * error will be specified by the return code from this function.
+ *
+ * The @workmem buffer should only be used by one function call at a time.
+ *
+ * @in: input buffer pointer
+ * @inlen: input buffer size
+ * @out: output buffer pointer
+ * @outlenp: output buffer size pointer
+ * @workmem: working memory buffer pointer, size determined by
+ * nx842_powernv_driver.workmem_size
+ * @fc: function code, see CCW Function Codes in nx-842.h
+ *
+ * Returns:
+ * 0 Success, output of length @outlenp stored in the buffer at @out
+ * -ENODEV Hardware unavailable
+ * -ENOSPC Output buffer is to small
+ * -EMSGSIZE Input buffer too large
+ * -EINVAL buffer constraints do not fix nx842_constraints
+ * -EPROTO hardware error during operation
+ * -ETIMEDOUT hardware did not complete operation in reasonable time
+ * -EINTR operation was aborted
+ */
+static int nx842_powernv_function(const unsigned char *in, unsigned int inlen,
+ unsigned char *out, unsigned int *outlenp,
+ void *workmem, int fc)
+{
+ struct coprocessor_request_block *crb;
+ struct coprocessor_status_block *csb;
+ struct nx842_workmem *wmem;
+ int ret;
+ u64 csb_addr;
+ u32 ccw;
+ unsigned int outlen = *outlenp;
+
+ wmem = PTR_ALIGN(workmem, WORKMEM_ALIGN);
+
+ *outlenp = 0;
+
+ /* shoudn't happen, we don't load without a coproc */
+ if (!nx842_ct) {
+ pr_err_ratelimited("coprocessor CT is 0");
+ return -ENODEV;
+ }
+
+ crb = &wmem->crb;
+ csb = &crb->csb;
+
+ /* Clear any previous values */
+ memset(crb, 0, sizeof(*crb));
+
+ /* set up DDLs */
+ ret = setup_ddl(&crb->source, wmem->ddl_in,
+ (unsigned char *)in, inlen, true);
+ if (ret)
+ return ret;
+ ret = setup_ddl(&crb->target, wmem->ddl_out,
+ out, outlen, false);
+ if (ret)
+ return ret;
+
+ /* set up CCW */
+ ccw = 0;
+ ccw = SET_FIELD(ccw, CCW_CT, nx842_ct);
+ ccw = SET_FIELD(ccw, CCW_CI_842, 0); /* use 0 for hw auto-selection */
+ ccw = SET_FIELD(ccw, CCW_FC_842, fc);
+
+ /* set up CRB's CSB addr */
+ csb_addr = nx842_get_pa(csb) & CRB_CSB_ADDRESS;
+ csb_addr |= CRB_CSB_AT; /* Addrs are phys */
+ crb->csb_addr = cpu_to_be64(csb_addr);
+
+ wmem->start = ktime_get();
+
+ /* do ICSWX */
+ ret = icswx(cpu_to_be32(ccw), crb);
+
+ pr_debug_ratelimited("icswx CR %x ccw %x crb->ccw %x\n", ret,
+ (unsigned int)ccw,
+ (unsigned int)be32_to_cpu(crb->ccw));
+
+ switch (ret) {
+ case ICSWX_INITIATED:
+ ret = wait_for_csb(wmem, csb);
+ break;
+ case ICSWX_BUSY:
+ pr_debug_ratelimited("842 Coprocessor busy\n");
+ ret = -EBUSY;
+ break;
+ case ICSWX_REJECTED:
+ pr_err_ratelimited("ICSWX rejected\n");
+ ret = -EPROTO;
+ break;
+ default:
+ pr_err_ratelimited("Invalid ICSWX return code %x\n", ret);
+ ret = -EPROTO;
+ break;
+ }
+
+ if (!ret)
+ *outlenp = be32_to_cpu(csb->count);
+
+ return ret;
+}
+
+/**
+ * nx842_powernv_compress - Compress data using the 842 algorithm
+ *
+ * Compression provided by the NX842 coprocessor on IBM PowerNV systems.
+ * The input buffer is compressed and the result is stored in the
+ * provided output buffer.
+ *
+ * Upon return from this function @outlen contains the length of the
+ * compressed data. If there is an error then @outlen will be 0 and an
+ * error will be specified by the return code from this function.
+ *
+ * @in: input buffer pointer
+ * @inlen: input buffer size
+ * @out: output buffer pointer
+ * @outlenp: output buffer size pointer
+ * @workmem: working memory buffer pointer, size determined by
+ * nx842_powernv_driver.workmem_size
+ *
+ * Returns: see @nx842_powernv_function()
+ */
+static int nx842_powernv_compress(const unsigned char *in, unsigned int inlen,
+ unsigned char *out, unsigned int *outlenp,
+ void *wmem)
+{
+ return nx842_powernv_function(in, inlen, out, outlenp,
+ wmem, CCW_FC_842_COMP_NOCRC);
+}
+
+/**
+ * nx842_powernv_decompress - Decompress data using the 842 algorithm
+ *
+ * Decompression provided by the NX842 coprocessor on IBM PowerNV systems.
+ * The input buffer is decompressed and the result is stored in the
+ * provided output buffer.
+ *
+ * Upon return from this function @outlen contains the length of the
+ * decompressed data. If there is an error then @outlen will be 0 and an
+ * error will be specified by the return code from this function.
+ *
+ * @in: input buffer pointer
+ * @inlen: input buffer size
+ * @out: output buffer pointer
+ * @outlenp: output buffer size pointer
+ * @workmem: working memory buffer pointer, size determined by
+ * nx842_powernv_driver.workmem_size
+ *
+ * Returns: see @nx842_powernv_function()
+ */
+static int nx842_powernv_decompress(const unsigned char *in, unsigned int inlen,
+ unsigned char *out, unsigned int *outlenp,
+ void *wmem)
+{
+ return nx842_powernv_function(in, inlen, out, outlenp,
+ wmem, CCW_FC_842_DECOMP_NOCRC);
+}
+
+static int __init nx842_powernv_probe(struct device_node *dn)
+{
+ struct nx842_coproc *coproc;
+ struct property *ct_prop, *ci_prop;
+ unsigned int ct, ci;
+ int chip_id;
+
+ chip_id = of_get_ibm_chip_id(dn);
+ if (chip_id < 0) {
+ pr_err("ibm,chip-id missing\n");
+ return -EINVAL;
+ }
+ ct_prop = of_find_property(dn, "ibm,842-coprocessor-type", NULL);
+ if (!ct_prop) {
+ pr_err("ibm,842-coprocessor-type missing\n");
+ return -EINVAL;
+ }
+ ct = be32_to_cpu(*(unsigned int *)ct_prop->value);
+ ci_prop = of_find_property(dn, "ibm,842-coprocessor-instance", NULL);
+ if (!ci_prop) {
+ pr_err("ibm,842-coprocessor-instance missing\n");
+ return -EINVAL;
+ }
+ ci = be32_to_cpu(*(unsigned int *)ci_prop->value);
+
+ coproc = kmalloc(sizeof(*coproc), GFP_KERNEL);
+ if (!coproc)
+ return -ENOMEM;
+
+ coproc->chip_id = chip_id;
+ coproc->ct = ct;
+ coproc->ci = ci;
+ INIT_LIST_HEAD(&coproc->list);
+ list_add(&coproc->list, &nx842_coprocs);
+
+ pr_info("coprocessor found on chip %d, CT %d CI %d\n", chip_id, ct, ci);
+
+ if (!nx842_ct)
+ nx842_ct = ct;
+ else if (nx842_ct != ct)
+ pr_err("NX842 chip %d, CT %d != first found CT %d\n",
+ chip_id, ct, nx842_ct);
+
+ return 0;
+}
+
+static struct nx842_constraints nx842_powernv_constraints = {
+ .alignment = DDE_BUFFER_ALIGN,
+ .multiple = DDE_BUFFER_LAST_MULT,
+ .minimum = DDE_BUFFER_LAST_MULT,
+ .maximum = (DDL_LEN_MAX - 1) * PAGE_SIZE,
+};
+
+static struct nx842_driver nx842_powernv_driver = {
+ .name = KBUILD_MODNAME,
+ .owner = THIS_MODULE,
+ .workmem_size = sizeof(struct nx842_workmem),
+ .constraints = &nx842_powernv_constraints,
+ .compress = nx842_powernv_compress,
+ .decompress = nx842_powernv_decompress,
+};
+
+static __init int nx842_powernv_init(void)
+{
+ struct device_node *dn;
+
+ /* verify workmem size/align restrictions */
+ BUILD_BUG_ON(WORKMEM_ALIGN % CRB_ALIGN);
+ BUILD_BUG_ON(CRB_ALIGN % DDE_ALIGN);
+ BUILD_BUG_ON(CRB_SIZE % DDE_ALIGN);
+ /* verify buffer size/align restrictions */
+ BUILD_BUG_ON(PAGE_SIZE % DDE_BUFFER_ALIGN);
+ BUILD_BUG_ON(DDE_BUFFER_ALIGN % DDE_BUFFER_SIZE_MULT);
+ BUILD_BUG_ON(DDE_BUFFER_SIZE_MULT % DDE_BUFFER_LAST_MULT);
+
+ pr_info("loading\n");
+
+ for_each_compatible_node(dn, NULL, "ibm,power-nx")
+ nx842_powernv_probe(dn);
+
+ if (!nx842_ct) {
+ pr_err("no coprocessors found\n");
+ return -ENODEV;
+ }
+
+ if (!nx842_platform_driver_set(&nx842_powernv_driver)) {
+ struct nx842_coproc *coproc, *n;
+
+ list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
+ list_del(&coproc->list);
+ kfree(coproc);
+ }
+
+ return -EEXIST;
+ }
+
+ pr_info("loaded\n");
+
+ return 0;
+}
+module_init(nx842_powernv_init);
+
+static void __exit nx842_powernv_exit(void)
+{
+ struct nx842_coproc *coproc, *n;
+
+ nx842_platform_driver_unset(&nx842_powernv_driver);
+
+ list_for_each_entry_safe(coproc, n, &nx842_coprocs, list) {
+ list_del(&coproc->list);
+ kfree(coproc);
+ }
+
+ pr_info("unloaded\n");
+}
+module_exit(nx842_powernv_exit);