irqchip/gic-v3-its: Macro-ize its_send_single_command

Most ITS commands do operate on a collection object, and require
a SYNC command to be performed on that collection in order to
guarantee the execution of the first command.

With GICv4 ITS, another set of commands perform similar operations
on a VPE object, and a VSYNC operations must be executed to guarantee
their execution.

Given the similarities (post a command, perform a synchronization
operation on a sync object), it makes sense to reuse the same
mechanism for both class of commands.

Let's start with turning its_send_single_command into a huge macro
that performs the bulk of the work, and a set of helpers that
make this macro usable for the GICv3 ITS commands.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 89da961e949ee245dca4a97469009047903c2cc8..7ad0fc8d2e2380080e44efa335c5e41b3f418fe6 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -494,43 +494,53 @@ static void its_wait_for_range_completion(struct its_node *its,
        }
 }
 
-static void its_send_single_command(struct its_node *its,
-                                   its_cmd_builder_t builder,
-                                   struct its_cmd_desc *desc)
-{
-       struct its_cmd_block *cmd, *sync_cmd, *next_cmd;
-       struct its_collection *sync_col;
-       unsigned long flags;
-
-       raw_spin_lock_irqsave(&its->lock, flags);
-
-       cmd = its_allocate_entry(its);
-       if (!cmd) {             /* We're soooooo screewed... */
-               pr_err_ratelimited("ITS can't allocate, dropping command\n");
-               raw_spin_unlock_irqrestore(&its->lock, flags);
-               return;
-       }
-       sync_col = builder(cmd, desc);
-       its_flush_cmd(its, cmd);
-
-       if (sync_col) {
-               sync_cmd = its_allocate_entry(its);
-               if (!sync_cmd) {
-                       pr_err_ratelimited("ITS can't SYNC, skipping\n");
-                       goto post;
-               }
-               its_encode_cmd(sync_cmd, GITS_CMD_SYNC);
-               its_encode_target(sync_cmd, sync_col->target_address);
-               its_fixup_cmd(sync_cmd);
-               its_flush_cmd(its, sync_cmd);
-       }
-
-post:
-       next_cmd = its_post_commands(its);
-       raw_spin_unlock_irqrestore(&its->lock, flags);
-
-       its_wait_for_range_completion(its, cmd, next_cmd);
-}
+/* Warning, macro hell follows */
+#define BUILD_SINGLE_CMD_FUNC(name, buildtype, synctype, buildfn)      \
+void name(struct its_node *its,                                                \
+         buildtype builder,                                            \
+         struct its_cmd_desc *desc)                                    \
+{                                                                      \
+       struct its_cmd_block *cmd, *sync_cmd, *next_cmd;                \
+       synctype *sync_obj;                                             \
+       unsigned long flags;                                            \
+                                                                       \
+       raw_spin_lock_irqsave(&its->lock, flags);                       \
+                                                                       \
+       cmd = its_allocate_entry(its);                                  \
+       if (!cmd) {             /* We're soooooo screewed... */         \
+               raw_spin_unlock_irqrestore(&its->lock, flags);          \
+               return;                                                 \
+       }                                                               \
+       sync_obj = builder(cmd, desc);                                  \
+       its_flush_cmd(its, cmd);                                        \
+                                                                       \
+       if (sync_obj) {                                                 \
+               sync_cmd = its_allocate_entry(its);                     \
+               if (!sync_cmd)                                          \
+                       goto post;                                      \
+                                                                       \
+               buildfn(sync_cmd, sync_obj);                            \
+               its_flush_cmd(its, sync_cmd);                           \
+       }                                                               \
+                                                                       \
+post:                                                                  \
+       next_cmd = its_post_commands(its);                              \
+       raw_spin_unlock_irqrestore(&its->lock, flags);                  \
+                                                                       \
+       its_wait_for_range_completion(its, cmd, next_cmd);              \
+}
+
+static void its_build_sync_cmd(struct its_cmd_block *sync_cmd,
+                              struct its_collection *sync_col)
+{
+       its_encode_cmd(sync_cmd, GITS_CMD_SYNC);
+       its_encode_target(sync_cmd, sync_col->target_address);
+
+       its_fixup_cmd(sync_cmd);
+}
+
+static BUILD_SINGLE_CMD_FUNC(its_send_single_command, its_cmd_builder_t,
+                            struct its_collection, its_build_sync_cmd)
 
 static void its_send_inv(struct its_device *dev, u32 event_id)
 {