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path: root/drivers/cdx/controller/mcdi.c
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Diffstat (limited to 'drivers/cdx/controller/mcdi.c')
-rw-r--r--drivers/cdx/controller/mcdi.c903
1 files changed, 903 insertions, 0 deletions
diff --git a/drivers/cdx/controller/mcdi.c b/drivers/cdx/controller/mcdi.c
new file mode 100644
index 000000000000..a211a2ca762e
--- /dev/null
+++ b/drivers/cdx/controller/mcdi.c
@@ -0,0 +1,903 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Management-Controller-to-Driver Interface
+ *
+ * Copyright 2008-2013 Solarflare Communications Inc.
+ * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
+ */
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/if_vlan.h>
+#include <linux/timer.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/device.h>
+#include <linux/rwsem.h>
+#include <linux/vmalloc.h>
+#include <net/netevent.h>
+#include <linux/log2.h>
+#include <linux/net_tstamp.h>
+#include <linux/wait.h>
+
+#include "bitfield.h"
+#include "mcdi.h"
+
+struct cdx_mcdi_copy_buffer {
+ struct cdx_dword buffer[DIV_ROUND_UP(MCDI_CTL_SDU_LEN_MAX, 4)];
+};
+
+#ifdef CONFIG_MCDI_LOGGING
+#define LOG_LINE_MAX (1024 - 32)
+#endif
+
+static void cdx_mcdi_cancel_cmd(struct cdx_mcdi *cdx, struct cdx_mcdi_cmd *cmd);
+static void cdx_mcdi_wait_for_cleanup(struct cdx_mcdi *cdx);
+static int cdx_mcdi_rpc_async_internal(struct cdx_mcdi *cdx,
+ struct cdx_mcdi_cmd *cmd,
+ unsigned int *handle);
+static void cdx_mcdi_start_or_queue(struct cdx_mcdi_iface *mcdi,
+ bool allow_retry);
+static void cdx_mcdi_cmd_start_or_queue(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd);
+static bool cdx_mcdi_complete_cmd(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd,
+ struct cdx_dword *outbuf,
+ int len,
+ struct list_head *cleanup_list);
+static void cdx_mcdi_timeout_cmd(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd,
+ struct list_head *cleanup_list);
+static void cdx_mcdi_cmd_work(struct work_struct *context);
+static void cdx_mcdi_mode_fail(struct cdx_mcdi *cdx, struct list_head *cleanup_list);
+static void _cdx_mcdi_display_error(struct cdx_mcdi *cdx, unsigned int cmd,
+ size_t inlen, int raw, int arg, int err_no);
+
+static bool cdx_cmd_cancelled(struct cdx_mcdi_cmd *cmd)
+{
+ return cmd->state == MCDI_STATE_RUNNING_CANCELLED;
+}
+
+static void cdx_mcdi_cmd_release(struct kref *ref)
+{
+ kfree(container_of(ref, struct cdx_mcdi_cmd, ref));
+}
+
+static unsigned int cdx_mcdi_cmd_handle(struct cdx_mcdi_cmd *cmd)
+{
+ return cmd->handle;
+}
+
+static void _cdx_mcdi_remove_cmd(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd,
+ struct list_head *cleanup_list)
+{
+ /* if cancelled, the completers have already been called */
+ if (cdx_cmd_cancelled(cmd))
+ return;
+
+ if (cmd->completer) {
+ list_add_tail(&cmd->cleanup_list, cleanup_list);
+ ++mcdi->outstanding_cleanups;
+ kref_get(&cmd->ref);
+ }
+}
+
+static void cdx_mcdi_remove_cmd(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd,
+ struct list_head *cleanup_list)
+{
+ list_del(&cmd->list);
+ _cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
+ cmd->state = MCDI_STATE_FINISHED;
+ kref_put(&cmd->ref, cdx_mcdi_cmd_release);
+ if (list_empty(&mcdi->cmd_list))
+ wake_up(&mcdi->cmd_complete_wq);
+}
+
+static unsigned long cdx_mcdi_rpc_timeout(struct cdx_mcdi *cdx, unsigned int cmd)
+{
+ if (!cdx->mcdi_ops->mcdi_rpc_timeout)
+ return MCDI_RPC_TIMEOUT;
+ else
+ return cdx->mcdi_ops->mcdi_rpc_timeout(cdx, cmd);
+}
+
+int cdx_mcdi_init(struct cdx_mcdi *cdx)
+{
+ struct cdx_mcdi_iface *mcdi;
+ int rc = -ENOMEM;
+
+ cdx->mcdi = kzalloc(sizeof(*cdx->mcdi), GFP_KERNEL);
+ if (!cdx->mcdi)
+ goto fail;
+
+ mcdi = cdx_mcdi_if(cdx);
+ mcdi->cdx = cdx;
+
+#ifdef CONFIG_MCDI_LOGGING
+ mcdi->logging_buffer = kmalloc(LOG_LINE_MAX, GFP_KERNEL);
+ if (!mcdi->logging_buffer)
+ goto fail2;
+#endif
+ mcdi->workqueue = alloc_ordered_workqueue("mcdi_wq", 0);
+ if (!mcdi->workqueue)
+ goto fail3;
+ mutex_init(&mcdi->iface_lock);
+ mcdi->mode = MCDI_MODE_EVENTS;
+ INIT_LIST_HEAD(&mcdi->cmd_list);
+ init_waitqueue_head(&mcdi->cmd_complete_wq);
+
+ mcdi->new_epoch = true;
+
+ return 0;
+fail3:
+#ifdef CONFIG_MCDI_LOGGING
+ kfree(mcdi->logging_buffer);
+fail2:
+#endif
+ kfree(cdx->mcdi);
+ cdx->mcdi = NULL;
+fail:
+ return rc;
+}
+
+void cdx_mcdi_finish(struct cdx_mcdi *cdx)
+{
+ struct cdx_mcdi_iface *mcdi;
+
+ mcdi = cdx_mcdi_if(cdx);
+ if (!mcdi)
+ return;
+
+ cdx_mcdi_wait_for_cleanup(cdx);
+
+#ifdef CONFIG_MCDI_LOGGING
+ kfree(mcdi->logging_buffer);
+#endif
+
+ destroy_workqueue(mcdi->workqueue);
+ kfree(cdx->mcdi);
+ cdx->mcdi = NULL;
+}
+
+static bool cdx_mcdi_flushed(struct cdx_mcdi_iface *mcdi, bool ignore_cleanups)
+{
+ bool flushed;
+
+ mutex_lock(&mcdi->iface_lock);
+ flushed = list_empty(&mcdi->cmd_list) &&
+ (ignore_cleanups || !mcdi->outstanding_cleanups);
+ mutex_unlock(&mcdi->iface_lock);
+ return flushed;
+}
+
+/* Wait for outstanding MCDI commands to complete. */
+static void cdx_mcdi_wait_for_cleanup(struct cdx_mcdi *cdx)
+{
+ struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
+
+ if (!mcdi)
+ return;
+
+ wait_event(mcdi->cmd_complete_wq,
+ cdx_mcdi_flushed(mcdi, false));
+}
+
+int cdx_mcdi_wait_for_quiescence(struct cdx_mcdi *cdx,
+ unsigned int timeout_jiffies)
+{
+ struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+ int rc = 0;
+
+ if (!mcdi)
+ return -EINVAL;
+
+ flush_workqueue(mcdi->workqueue);
+
+ add_wait_queue(&mcdi->cmd_complete_wq, &wait);
+
+ while (!cdx_mcdi_flushed(mcdi, true)) {
+ rc = wait_woken(&wait, TASK_IDLE, timeout_jiffies);
+ if (rc)
+ continue;
+ break;
+ }
+
+ remove_wait_queue(&mcdi->cmd_complete_wq, &wait);
+
+ if (rc > 0)
+ rc = 0;
+ else if (rc == 0)
+ rc = -ETIMEDOUT;
+
+ return rc;
+}
+
+static u8 cdx_mcdi_payload_csum(const struct cdx_dword *hdr, size_t hdr_len,
+ const struct cdx_dword *sdu, size_t sdu_len)
+{
+ u8 *p = (u8 *)hdr;
+ u8 csum = 0;
+ int i;
+
+ for (i = 0; i < hdr_len; i++)
+ csum += p[i];
+
+ p = (u8 *)sdu;
+ for (i = 0; i < sdu_len; i++)
+ csum += p[i];
+
+ return ~csum & 0xff;
+}
+
+static void cdx_mcdi_send_request(struct cdx_mcdi *cdx,
+ struct cdx_mcdi_cmd *cmd)
+{
+ struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
+ const struct cdx_dword *inbuf = cmd->inbuf;
+ size_t inlen = cmd->inlen;
+ struct cdx_dword hdr[2];
+ size_t hdr_len;
+ bool not_epoch;
+ u32 xflags;
+#ifdef CONFIG_MCDI_LOGGING
+ char *buf;
+#endif
+
+ if (!mcdi)
+ return;
+#ifdef CONFIG_MCDI_LOGGING
+ buf = mcdi->logging_buffer; /* page-sized */
+#endif
+
+ mcdi->prev_seq = cmd->seq;
+ mcdi->seq_held_by[cmd->seq] = cmd;
+ mcdi->db_held_by = cmd;
+ cmd->started = jiffies;
+
+ not_epoch = !mcdi->new_epoch;
+ xflags = 0;
+
+ /* MCDI v2 */
+ WARN_ON(inlen > MCDI_CTL_SDU_LEN_MAX_V2);
+ CDX_POPULATE_DWORD_7(hdr[0],
+ MCDI_HEADER_RESPONSE, 0,
+ MCDI_HEADER_RESYNC, 1,
+ MCDI_HEADER_CODE, MC_CMD_V2_EXTN,
+ MCDI_HEADER_DATALEN, 0,
+ MCDI_HEADER_SEQ, cmd->seq,
+ MCDI_HEADER_XFLAGS, xflags,
+ MCDI_HEADER_NOT_EPOCH, not_epoch);
+ CDX_POPULATE_DWORD_3(hdr[1],
+ MC_CMD_V2_EXTN_IN_EXTENDED_CMD, cmd->cmd,
+ MC_CMD_V2_EXTN_IN_ACTUAL_LEN, inlen,
+ MC_CMD_V2_EXTN_IN_MESSAGE_TYPE,
+ MC_CMD_V2_EXTN_IN_MCDI_MESSAGE_TYPE_PLATFORM);
+ hdr_len = 8;
+
+#ifdef CONFIG_MCDI_LOGGING
+ if (!WARN_ON_ONCE(!buf)) {
+ const struct cdx_dword *frags[] = { hdr, inbuf };
+ const size_t frag_len[] = { hdr_len, round_up(inlen, 4) };
+ int bytes = 0;
+ int i, j;
+
+ for (j = 0; j < ARRAY_SIZE(frags); j++) {
+ const struct cdx_dword *frag;
+
+ frag = frags[j];
+ for (i = 0;
+ i < frag_len[j] / 4;
+ i++) {
+ /*
+ * Do not exceed the internal printk limit.
+ * The string before that is just over 70 bytes.
+ */
+ if ((bytes + 75) > LOG_LINE_MAX) {
+ pr_info("MCDI RPC REQ:%s \\\n", buf);
+ bytes = 0;
+ }
+ bytes += snprintf(buf + bytes,
+ LOG_LINE_MAX - bytes, " %08x",
+ le32_to_cpu(frag[i].cdx_u32));
+ }
+ }
+
+ pr_info("MCDI RPC REQ:%s\n", buf);
+ }
+#endif
+ hdr[0].cdx_u32 |= (__force __le32)(cdx_mcdi_payload_csum(hdr, hdr_len, inbuf, inlen) <<
+ MCDI_HEADER_XFLAGS_LBN);
+ cdx->mcdi_ops->mcdi_request(cdx, hdr, hdr_len, inbuf, inlen);
+
+ mcdi->new_epoch = false;
+}
+
+static int cdx_mcdi_errno(struct cdx_mcdi *cdx, unsigned int mcdi_err)
+{
+ switch (mcdi_err) {
+ case 0:
+ case MC_CMD_ERR_QUEUE_FULL:
+ return mcdi_err;
+ case MC_CMD_ERR_EPERM:
+ return -EPERM;
+ case MC_CMD_ERR_ENOENT:
+ return -ENOENT;
+ case MC_CMD_ERR_EINTR:
+ return -EINTR;
+ case MC_CMD_ERR_EAGAIN:
+ return -EAGAIN;
+ case MC_CMD_ERR_EACCES:
+ return -EACCES;
+ case MC_CMD_ERR_EBUSY:
+ return -EBUSY;
+ case MC_CMD_ERR_EINVAL:
+ return -EINVAL;
+ case MC_CMD_ERR_ERANGE:
+ return -ERANGE;
+ case MC_CMD_ERR_EDEADLK:
+ return -EDEADLK;
+ case MC_CMD_ERR_ENOSYS:
+ return -EOPNOTSUPP;
+ case MC_CMD_ERR_ETIME:
+ return -ETIME;
+ case MC_CMD_ERR_EALREADY:
+ return -EALREADY;
+ case MC_CMD_ERR_ENOSPC:
+ return -ENOSPC;
+ case MC_CMD_ERR_ENOMEM:
+ return -ENOMEM;
+ case MC_CMD_ERR_ENOTSUP:
+ return -EOPNOTSUPP;
+ case MC_CMD_ERR_ALLOC_FAIL:
+ return -ENOBUFS;
+ case MC_CMD_ERR_MAC_EXIST:
+ return -EADDRINUSE;
+ case MC_CMD_ERR_NO_EVB_PORT:
+ return -EAGAIN;
+ default:
+ return -EPROTO;
+ }
+}
+
+static void cdx_mcdi_process_cleanup_list(struct cdx_mcdi *cdx,
+ struct list_head *cleanup_list)
+{
+ struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
+ unsigned int cleanups = 0;
+
+ if (!mcdi)
+ return;
+
+ while (!list_empty(cleanup_list)) {
+ struct cdx_mcdi_cmd *cmd =
+ list_first_entry(cleanup_list,
+ struct cdx_mcdi_cmd, cleanup_list);
+ cmd->completer(cdx, cmd->cookie, cmd->rc,
+ cmd->outbuf, cmd->outlen);
+ list_del(&cmd->cleanup_list);
+ kref_put(&cmd->ref, cdx_mcdi_cmd_release);
+ ++cleanups;
+ }
+
+ if (cleanups) {
+ bool all_done;
+
+ mutex_lock(&mcdi->iface_lock);
+ CDX_WARN_ON_PARANOID(cleanups > mcdi->outstanding_cleanups);
+ all_done = (mcdi->outstanding_cleanups -= cleanups) == 0;
+ mutex_unlock(&mcdi->iface_lock);
+ if (all_done)
+ wake_up(&mcdi->cmd_complete_wq);
+ }
+}
+
+static void _cdx_mcdi_cancel_cmd(struct cdx_mcdi_iface *mcdi,
+ unsigned int handle,
+ struct list_head *cleanup_list)
+{
+ struct cdx_mcdi_cmd *cmd;
+
+ list_for_each_entry(cmd, &mcdi->cmd_list, list)
+ if (cdx_mcdi_cmd_handle(cmd) == handle) {
+ switch (cmd->state) {
+ case MCDI_STATE_QUEUED:
+ case MCDI_STATE_RETRY:
+ pr_debug("command %#x inlen %zu cancelled in queue\n",
+ cmd->cmd, cmd->inlen);
+ /* if not yet running, properly cancel it */
+ cmd->rc = -EPIPE;
+ cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
+ break;
+ case MCDI_STATE_RUNNING:
+ case MCDI_STATE_RUNNING_CANCELLED:
+ case MCDI_STATE_FINISHED:
+ default:
+ /* invalid state? */
+ WARN_ON(1);
+ }
+ break;
+ }
+}
+
+static void cdx_mcdi_cancel_cmd(struct cdx_mcdi *cdx, struct cdx_mcdi_cmd *cmd)
+{
+ struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
+ LIST_HEAD(cleanup_list);
+
+ if (!mcdi)
+ return;
+
+ mutex_lock(&mcdi->iface_lock);
+ cdx_mcdi_timeout_cmd(mcdi, cmd, &cleanup_list);
+ mutex_unlock(&mcdi->iface_lock);
+ cdx_mcdi_process_cleanup_list(cdx, &cleanup_list);
+}
+
+struct cdx_mcdi_blocking_data {
+ struct kref ref;
+ bool done;
+ wait_queue_head_t wq;
+ int rc;
+ struct cdx_dword *outbuf;
+ size_t outlen;
+ size_t outlen_actual;
+};
+
+static void cdx_mcdi_blocking_data_release(struct kref *ref)
+{
+ kfree(container_of(ref, struct cdx_mcdi_blocking_data, ref));
+}
+
+static void cdx_mcdi_rpc_completer(struct cdx_mcdi *cdx, unsigned long cookie,
+ int rc, struct cdx_dword *outbuf,
+ size_t outlen_actual)
+{
+ struct cdx_mcdi_blocking_data *wait_data =
+ (struct cdx_mcdi_blocking_data *)cookie;
+
+ wait_data->rc = rc;
+ memcpy(wait_data->outbuf, outbuf,
+ min(outlen_actual, wait_data->outlen));
+ wait_data->outlen_actual = outlen_actual;
+ /* memory barrier */
+ smp_wmb();
+ wait_data->done = true;
+ wake_up(&wait_data->wq);
+ kref_put(&wait_data->ref, cdx_mcdi_blocking_data_release);
+}
+
+static int cdx_mcdi_rpc_sync(struct cdx_mcdi *cdx, unsigned int cmd,
+ const struct cdx_dword *inbuf, size_t inlen,
+ struct cdx_dword *outbuf, size_t outlen,
+ size_t *outlen_actual, bool quiet)
+{
+ struct cdx_mcdi_blocking_data *wait_data;
+ struct cdx_mcdi_cmd *cmd_item;
+ unsigned int handle;
+ int rc;
+
+ if (outlen_actual)
+ *outlen_actual = 0;
+
+ wait_data = kmalloc(sizeof(*wait_data), GFP_KERNEL);
+ if (!wait_data)
+ return -ENOMEM;
+
+ cmd_item = kmalloc(sizeof(*cmd_item), GFP_KERNEL);
+ if (!cmd_item) {
+ kfree(wait_data);
+ return -ENOMEM;
+ }
+
+ kref_init(&wait_data->ref);
+ wait_data->done = false;
+ init_waitqueue_head(&wait_data->wq);
+ wait_data->outbuf = outbuf;
+ wait_data->outlen = outlen;
+
+ kref_init(&cmd_item->ref);
+ cmd_item->quiet = quiet;
+ cmd_item->cookie = (unsigned long)wait_data;
+ cmd_item->completer = &cdx_mcdi_rpc_completer;
+ cmd_item->cmd = cmd;
+ cmd_item->inlen = inlen;
+ cmd_item->inbuf = inbuf;
+
+ /* Claim an extra reference for the completer to put. */
+ kref_get(&wait_data->ref);
+ rc = cdx_mcdi_rpc_async_internal(cdx, cmd_item, &handle);
+ if (rc) {
+ kref_put(&wait_data->ref, cdx_mcdi_blocking_data_release);
+ goto out;
+ }
+
+ if (!wait_event_timeout(wait_data->wq, wait_data->done,
+ cdx_mcdi_rpc_timeout(cdx, cmd)) &&
+ !wait_data->done) {
+ pr_err("MC command 0x%x inlen %zu timed out (sync)\n",
+ cmd, inlen);
+
+ cdx_mcdi_cancel_cmd(cdx, cmd_item);
+
+ wait_data->rc = -ETIMEDOUT;
+ wait_data->outlen_actual = 0;
+ }
+
+ if (outlen_actual)
+ *outlen_actual = wait_data->outlen_actual;
+ rc = wait_data->rc;
+
+out:
+ kref_put(&wait_data->ref, cdx_mcdi_blocking_data_release);
+
+ return rc;
+}
+
+static bool cdx_mcdi_get_seq(struct cdx_mcdi_iface *mcdi, unsigned char *seq)
+{
+ *seq = mcdi->prev_seq;
+ do {
+ *seq = (*seq + 1) % ARRAY_SIZE(mcdi->seq_held_by);
+ } while (mcdi->seq_held_by[*seq] && *seq != mcdi->prev_seq);
+ return !mcdi->seq_held_by[*seq];
+}
+
+static int cdx_mcdi_rpc_async_internal(struct cdx_mcdi *cdx,
+ struct cdx_mcdi_cmd *cmd,
+ unsigned int *handle)
+{
+ struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
+ LIST_HEAD(cleanup_list);
+
+ if (!mcdi) {
+ kref_put(&cmd->ref, cdx_mcdi_cmd_release);
+ return -ENETDOWN;
+ }
+
+ if (mcdi->mode == MCDI_MODE_FAIL) {
+ kref_put(&cmd->ref, cdx_mcdi_cmd_release);
+ return -ENETDOWN;
+ }
+
+ cmd->mcdi = mcdi;
+ INIT_WORK(&cmd->work, cdx_mcdi_cmd_work);
+ INIT_LIST_HEAD(&cmd->list);
+ INIT_LIST_HEAD(&cmd->cleanup_list);
+ cmd->rc = 0;
+ cmd->outbuf = NULL;
+ cmd->outlen = 0;
+
+ queue_work(mcdi->workqueue, &cmd->work);
+ return 0;
+}
+
+static void cdx_mcdi_cmd_start_or_queue(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd)
+{
+ struct cdx_mcdi *cdx = mcdi->cdx;
+ u8 seq;
+
+ if (!mcdi->db_held_by &&
+ cdx_mcdi_get_seq(mcdi, &seq)) {
+ cmd->seq = seq;
+ cmd->reboot_seen = false;
+ cdx_mcdi_send_request(cdx, cmd);
+ cmd->state = MCDI_STATE_RUNNING;
+ } else {
+ cmd->state = MCDI_STATE_QUEUED;
+ }
+}
+
+/* try to advance other commands */
+static void cdx_mcdi_start_or_queue(struct cdx_mcdi_iface *mcdi,
+ bool allow_retry)
+{
+ struct cdx_mcdi_cmd *cmd, *tmp;
+
+ list_for_each_entry_safe(cmd, tmp, &mcdi->cmd_list, list)
+ if (cmd->state == MCDI_STATE_QUEUED ||
+ (cmd->state == MCDI_STATE_RETRY && allow_retry))
+ cdx_mcdi_cmd_start_or_queue(mcdi, cmd);
+}
+
+void cdx_mcdi_process_cmd(struct cdx_mcdi *cdx, struct cdx_dword *outbuf, int len)
+{
+ struct cdx_mcdi_iface *mcdi;
+ struct cdx_mcdi_cmd *cmd;
+ LIST_HEAD(cleanup_list);
+ unsigned int respseq;
+
+ if (!len || !outbuf) {
+ pr_err("Got empty MC response\n");
+ return;
+ }
+
+ mcdi = cdx_mcdi_if(cdx);
+ if (!mcdi)
+ return;
+
+ respseq = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_SEQ);
+
+ mutex_lock(&mcdi->iface_lock);
+ cmd = mcdi->seq_held_by[respseq];
+
+ if (cmd) {
+ if (cmd->state == MCDI_STATE_FINISHED) {
+ mutex_unlock(&mcdi->iface_lock);
+ kref_put(&cmd->ref, cdx_mcdi_cmd_release);
+ return;
+ }
+
+ cdx_mcdi_complete_cmd(mcdi, cmd, outbuf, len, &cleanup_list);
+ } else {
+ pr_err("MC response unexpected for seq : %0X\n", respseq);
+ }
+
+ mutex_unlock(&mcdi->iface_lock);
+
+ cdx_mcdi_process_cleanup_list(mcdi->cdx, &cleanup_list);
+}
+
+static void cdx_mcdi_cmd_work(struct work_struct *context)
+{
+ struct cdx_mcdi_cmd *cmd =
+ container_of(context, struct cdx_mcdi_cmd, work);
+ struct cdx_mcdi_iface *mcdi = cmd->mcdi;
+
+ mutex_lock(&mcdi->iface_lock);
+
+ cmd->handle = mcdi->prev_handle++;
+ list_add_tail(&cmd->list, &mcdi->cmd_list);
+ cdx_mcdi_cmd_start_or_queue(mcdi, cmd);
+
+ mutex_unlock(&mcdi->iface_lock);
+}
+
+/*
+ * Returns true if the MCDI module is finished with the command.
+ * (examples of false would be if the command was proxied, or it was
+ * rejected by the MC due to lack of resources and requeued).
+ */
+static bool cdx_mcdi_complete_cmd(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd,
+ struct cdx_dword *outbuf,
+ int len,
+ struct list_head *cleanup_list)
+{
+ size_t resp_hdr_len, resp_data_len;
+ struct cdx_mcdi *cdx = mcdi->cdx;
+ unsigned int respcmd, error;
+ bool completed = false;
+ int rc;
+
+ /* ensure the command can't go away before this function returns */
+ kref_get(&cmd->ref);
+
+ respcmd = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_CODE);
+ error = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_ERROR);
+
+ if (respcmd != MC_CMD_V2_EXTN) {
+ resp_hdr_len = 4;
+ resp_data_len = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_DATALEN);
+ } else {
+ resp_data_len = 0;
+ resp_hdr_len = 8;
+ if (len >= 8)
+ resp_data_len =
+ CDX_DWORD_FIELD(outbuf[1], MC_CMD_V2_EXTN_IN_ACTUAL_LEN);
+ }
+
+ if ((resp_hdr_len + resp_data_len) > len) {
+ pr_warn("Incomplete MCDI response received %d. Expected %zu\n",
+ len, (resp_hdr_len + resp_data_len));
+ resp_data_len = 0;
+ }
+
+#ifdef CONFIG_MCDI_LOGGING
+ if (!WARN_ON_ONCE(!mcdi->logging_buffer)) {
+ char *log = mcdi->logging_buffer;
+ int i, bytes = 0;
+ size_t rlen;
+
+ WARN_ON_ONCE(resp_hdr_len % 4);
+
+ rlen = resp_hdr_len / 4 + DIV_ROUND_UP(resp_data_len, 4);
+
+ for (i = 0; i < rlen; i++) {
+ if ((bytes + 75) > LOG_LINE_MAX) {
+ pr_info("MCDI RPC RESP:%s \\\n", log);
+ bytes = 0;
+ }
+ bytes += snprintf(log + bytes, LOG_LINE_MAX - bytes,
+ " %08x", le32_to_cpu(outbuf[i].cdx_u32));
+ }
+
+ pr_info("MCDI RPC RESP:%s\n", log);
+ }
+#endif
+
+ if (error && resp_data_len == 0) {
+ /* MC rebooted during command */
+ rc = -EIO;
+ } else {
+ if (WARN_ON_ONCE(error && resp_data_len < 4))
+ resp_data_len = 4;
+ if (error) {
+ rc = CDX_DWORD_FIELD(outbuf[resp_hdr_len / 4], CDX_DWORD);
+ if (!cmd->quiet) {
+ int err_arg = 0;
+
+ if (resp_data_len >= MC_CMD_ERR_ARG_OFST + 4) {
+ int offset = (resp_hdr_len + MC_CMD_ERR_ARG_OFST) / 4;
+
+ err_arg = CDX_DWORD_VAL(outbuf[offset]);
+ }
+
+ _cdx_mcdi_display_error(cdx, cmd->cmd,
+ cmd->inlen, rc, err_arg,
+ cdx_mcdi_errno(cdx, rc));
+ }
+ rc = cdx_mcdi_errno(cdx, rc);
+ } else {
+ rc = 0;
+ }
+ }
+
+ /* free doorbell */
+ if (mcdi->db_held_by == cmd)
+ mcdi->db_held_by = NULL;
+
+ if (cdx_cmd_cancelled(cmd)) {
+ list_del(&cmd->list);
+ kref_put(&cmd->ref, cdx_mcdi_cmd_release);
+ completed = true;
+ } else if (rc == MC_CMD_ERR_QUEUE_FULL) {
+ cmd->state = MCDI_STATE_RETRY;
+ } else {
+ cmd->rc = rc;
+ cmd->outbuf = outbuf + DIV_ROUND_UP(resp_hdr_len, 4);
+ cmd->outlen = resp_data_len;
+ cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
+ completed = true;
+ }
+
+ /* free sequence number and buffer */
+ mcdi->seq_held_by[cmd->seq] = NULL;
+
+ cdx_mcdi_start_or_queue(mcdi, rc != MC_CMD_ERR_QUEUE_FULL);
+
+ /* wake up anyone waiting for flush */
+ wake_up(&mcdi->cmd_complete_wq);
+
+ kref_put(&cmd->ref, cdx_mcdi_cmd_release);
+
+ return completed;
+}
+
+static void cdx_mcdi_timeout_cmd(struct cdx_mcdi_iface *mcdi,
+ struct cdx_mcdi_cmd *cmd,
+ struct list_head *cleanup_list)
+{
+ struct cdx_mcdi *cdx = mcdi->cdx;
+
+ pr_err("MC command 0x%x inlen %zu state %d timed out after %u ms\n",
+ cmd->cmd, cmd->inlen, cmd->state,
+ jiffies_to_msecs(jiffies - cmd->started));
+
+ cmd->rc = -ETIMEDOUT;
+ cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);
+
+ cdx_mcdi_mode_fail(cdx, cleanup_list);
+}
+
+/**
+ * cdx_mcdi_rpc - Issue an MCDI command and wait for completion
+ * @cdx: NIC through which to issue the command
+ * @cmd: Command type number
+ * @inbuf: Command parameters
+ * @inlen: Length of command parameters, in bytes. Must be a multiple
+ * of 4 and no greater than %MCDI_CTL_SDU_LEN_MAX_V1.
+ * @outbuf: Response buffer. May be %NULL if @outlen is 0.
+ * @outlen: Length of response buffer, in bytes. If the actual
+ * response is longer than @outlen & ~3, it will be truncated
+ * to that length.
+ * @outlen_actual: Pointer through which to return the actual response
+ * length. May be %NULL if this is not needed.
+ *
+ * This function may sleep and therefore must be called in process
+ * context.
+ *
+ * Return: A negative error code, or zero if successful. The error
+ * code may come from the MCDI response or may indicate a failure
+ * to communicate with the MC. In the former case, the response
+ * will still be copied to @outbuf and *@outlen_actual will be
+ * set accordingly. In the latter case, *@outlen_actual will be
+ * set to zero.
+ */
+int cdx_mcdi_rpc(struct cdx_mcdi *cdx, unsigned int cmd,
+ const struct cdx_dword *inbuf, size_t inlen,
+ struct cdx_dword *outbuf, size_t outlen,
+ size_t *outlen_actual)
+{
+ return cdx_mcdi_rpc_sync(cdx, cmd, inbuf, inlen, outbuf, outlen,
+ outlen_actual, false);
+}
+
+/**
+ * cdx_mcdi_rpc_async - Schedule an MCDI command to run asynchronously
+ * @cdx: NIC through which to issue the command
+ * @cmd: Command type number
+ * @inbuf: Command parameters
+ * @inlen: Length of command parameters, in bytes
+ * @complete: Function to be called on completion or cancellation.
+ * @cookie: Arbitrary value to be passed to @complete.
+ *
+ * This function does not sleep and therefore may be called in atomic
+ * context. It will fail if event queues are disabled or if MCDI
+ * event completions have been disabled due to an error.
+ *
+ * If it succeeds, the @complete function will be called exactly once
+ * in process context, when one of the following occurs:
+ * (a) the completion event is received (in process context)
+ * (b) event queues are disabled (in the process that disables them)
+ */
+int
+cdx_mcdi_rpc_async(struct cdx_mcdi *cdx, unsigned int cmd,
+ const struct cdx_dword *inbuf, size_t inlen,
+ cdx_mcdi_async_completer *complete, unsigned long cookie)
+{
+ struct cdx_mcdi_cmd *cmd_item =
+ kmalloc(sizeof(struct cdx_mcdi_cmd) + inlen, GFP_ATOMIC);
+
+ if (!cmd_item)
+ return -ENOMEM;
+
+ kref_init(&cmd_item->ref);
+ cmd_item->quiet = true;
+ cmd_item->cookie = cookie;
+ cmd_item->completer = complete;
+ cmd_item->cmd = cmd;
+ cmd_item->inlen = inlen;
+ /* inbuf is probably not valid after return, so take a copy */
+ cmd_item->inbuf = (struct cdx_dword *)(cmd_item + 1);
+ memcpy(cmd_item + 1, inbuf, inlen);
+
+ return cdx_mcdi_rpc_async_internal(cdx, cmd_item, NULL);
+}
+
+static void _cdx_mcdi_display_error(struct cdx_mcdi *cdx, unsigned int cmd,
+ size_t inlen, int raw, int arg, int err_no)
+{
+ pr_err("MC command 0x%x inlen %d failed err_no=%d (raw=%d) arg=%d\n",
+ cmd, (int)inlen, err_no, raw, arg);
+}
+
+/*
+ * Set MCDI mode to fail to prevent any new commands, then cancel any
+ * outstanding commands.
+ * Caller must hold the mcdi iface_lock.
+ */
+static void cdx_mcdi_mode_fail(struct cdx_mcdi *cdx, struct list_head *cleanup_list)
+{
+ struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);
+
+ if (!mcdi)
+ return;
+
+ mcdi->mode = MCDI_MODE_FAIL;
+
+ while (!list_empty(&mcdi->cmd_list)) {
+ struct cdx_mcdi_cmd *cmd;
+
+ cmd = list_first_entry(&mcdi->cmd_list, struct cdx_mcdi_cmd,
+ list);
+ _cdx_mcdi_cancel_cmd(mcdi, cdx_mcdi_cmd_handle(cmd), cleanup_list);
+ }
+}