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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/powerpc/platforms/powernv/opal-async.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/powerpc/platforms/powernv/opal-async.c')
-rw-r--r--kernel/arch/powerpc/platforms/powernv/opal-async.c208
1 files changed, 208 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/platforms/powernv/opal-async.c b/kernel/arch/powerpc/platforms/powernv/opal-async.c
new file mode 100644
index 000000000..693b6cdac
--- /dev/null
+++ b/kernel/arch/powerpc/platforms/powernv/opal-async.c
@@ -0,0 +1,208 @@
+/*
+ * PowerNV OPAL asynchronous completion interfaces
+ *
+ * Copyright 2013 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.
+ */
+
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/semaphore.h>
+#include <linux/spinlock.h>
+#include <linux/wait.h>
+#include <linux/gfp.h>
+#include <linux/of.h>
+#include <asm/machdep.h>
+#include <asm/opal.h>
+
+#define N_ASYNC_COMPLETIONS 64
+
+static DECLARE_BITMAP(opal_async_complete_map, N_ASYNC_COMPLETIONS) = {~0UL};
+static DECLARE_BITMAP(opal_async_token_map, N_ASYNC_COMPLETIONS);
+static DECLARE_WAIT_QUEUE_HEAD(opal_async_wait);
+static DEFINE_SPINLOCK(opal_async_comp_lock);
+static struct semaphore opal_async_sem;
+static struct opal_msg *opal_async_responses;
+static unsigned int opal_max_async_tokens;
+
+int __opal_async_get_token(void)
+{
+ unsigned long flags;
+ int token;
+
+ spin_lock_irqsave(&opal_async_comp_lock, flags);
+ token = find_first_bit(opal_async_complete_map, opal_max_async_tokens);
+ if (token >= opal_max_async_tokens) {
+ token = -EBUSY;
+ goto out;
+ }
+
+ if (__test_and_set_bit(token, opal_async_token_map)) {
+ token = -EBUSY;
+ goto out;
+ }
+
+ __clear_bit(token, opal_async_complete_map);
+
+out:
+ spin_unlock_irqrestore(&opal_async_comp_lock, flags);
+ return token;
+}
+
+int opal_async_get_token_interruptible(void)
+{
+ int token;
+
+ /* Wait until a token is available */
+ if (down_interruptible(&opal_async_sem))
+ return -ERESTARTSYS;
+
+ token = __opal_async_get_token();
+ if (token < 0)
+ up(&opal_async_sem);
+
+ return token;
+}
+EXPORT_SYMBOL_GPL(opal_async_get_token_interruptible);
+
+int __opal_async_release_token(int token)
+{
+ unsigned long flags;
+
+ if (token < 0 || token >= opal_max_async_tokens) {
+ pr_err("%s: Passed token is out of range, token %d\n",
+ __func__, token);
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&opal_async_comp_lock, flags);
+ __set_bit(token, opal_async_complete_map);
+ __clear_bit(token, opal_async_token_map);
+ spin_unlock_irqrestore(&opal_async_comp_lock, flags);
+
+ return 0;
+}
+
+int opal_async_release_token(int token)
+{
+ int ret;
+
+ ret = __opal_async_release_token(token);
+ if (ret)
+ return ret;
+
+ up(&opal_async_sem);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(opal_async_release_token);
+
+int opal_async_wait_response(uint64_t token, struct opal_msg *msg)
+{
+ if (token >= opal_max_async_tokens) {
+ pr_err("%s: Invalid token passed\n", __func__);
+ return -EINVAL;
+ }
+
+ if (!msg) {
+ pr_err("%s: Invalid message pointer passed\n", __func__);
+ return -EINVAL;
+ }
+
+ wait_event(opal_async_wait, test_bit(token, opal_async_complete_map));
+ memcpy(msg, &opal_async_responses[token], sizeof(*msg));
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(opal_async_wait_response);
+
+static int opal_async_comp_event(struct notifier_block *nb,
+ unsigned long msg_type, void *msg)
+{
+ struct opal_msg *comp_msg = msg;
+ unsigned long flags;
+ uint64_t token;
+
+ if (msg_type != OPAL_MSG_ASYNC_COMP)
+ return 0;
+
+ token = be64_to_cpu(comp_msg->params[0]);
+ memcpy(&opal_async_responses[token], comp_msg, sizeof(*comp_msg));
+ spin_lock_irqsave(&opal_async_comp_lock, flags);
+ __set_bit(token, opal_async_complete_map);
+ spin_unlock_irqrestore(&opal_async_comp_lock, flags);
+
+ wake_up(&opal_async_wait);
+
+ return 0;
+}
+
+static struct notifier_block opal_async_comp_nb = {
+ .notifier_call = opal_async_comp_event,
+ .next = NULL,
+ .priority = 0,
+};
+
+static int __init opal_async_comp_init(void)
+{
+ struct device_node *opal_node;
+ const __be32 *async;
+ int err;
+
+ opal_node = of_find_node_by_path("/ibm,opal");
+ if (!opal_node) {
+ pr_err("%s: Opal node not found\n", __func__);
+ err = -ENOENT;
+ goto out;
+ }
+
+ async = of_get_property(opal_node, "opal-msg-async-num", NULL);
+ if (!async) {
+ pr_err("%s: %s has no opal-msg-async-num\n",
+ __func__, opal_node->full_name);
+ err = -ENOENT;
+ goto out_opal_node;
+ }
+
+ opal_max_async_tokens = be32_to_cpup(async);
+ if (opal_max_async_tokens > N_ASYNC_COMPLETIONS)
+ opal_max_async_tokens = N_ASYNC_COMPLETIONS;
+
+ err = opal_message_notifier_register(OPAL_MSG_ASYNC_COMP,
+ &opal_async_comp_nb);
+ if (err) {
+ pr_err("%s: Can't register OPAL event notifier (%d)\n",
+ __func__, err);
+ goto out_opal_node;
+ }
+
+ opal_async_responses = kzalloc(
+ sizeof(*opal_async_responses) * opal_max_async_tokens,
+ GFP_KERNEL);
+ if (!opal_async_responses) {
+ pr_err("%s: Out of memory, failed to do asynchronous "
+ "completion init\n", __func__);
+ err = -ENOMEM;
+ goto out_opal_node;
+ }
+
+ /* Initialize to 1 less than the maximum tokens available, as we may
+ * require to pop one during emergency through synchronous call to
+ * __opal_async_get_token()
+ */
+ sema_init(&opal_async_sem, opal_max_async_tokens - 1);
+
+out_opal_node:
+ of_node_put(opal_node);
+out:
+ return err;
+}
+machine_subsys_initcall(powernv, opal_async_comp_init);