remoteproc: k3: Refactor .attach rproc ops into common driver

The .attach rproc ops implementations in TI K3 R5, DSP and M4 drivers
are NOPs. Refactor the implementations into ti_k3_common.c driver
as k3_rproc_attach() and register this common function as .attach ops in
R5, DSP and M4 drivers.

Signed-off-by: Beleswar Padhi <b-padhi@ti.com>
Tested-by: Judith Mendez <jm@ti.com>
Reviewed-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20250513054510.3439842-30-b-padhi@ti.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

Author: 3V3RYONE

drivers/remoteproc/ti_k3_common.c

@@ -296,5 +296,17 @@ int k3_rproc_stop(struct rproc *rproc)
 }
 EXPORT_SYMBOL_GPL(k3_rproc_stop);
 
+/*
+ * Attach to a running remote processor (IPC-only mode)
+ *
+ * The rproc attach callback is a NOP. The remote processor is already booted,
+ * and all required resources have been acquired during probe routine, so there
+ * is no need to issue any TI-SCI commands to boot the remote cores in IPC-only
+ * mode. This callback is invoked only in IPC-only mode and exists because
+ * rproc_validate() checks for its existence.
+ */
+int k3_rproc_attach(struct rproc *rproc) { return 0; }
+EXPORT_SYMBOL_GPL(k3_rproc_attach);
+
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("TI K3 common Remoteproc code");

drivers/remoteproc/ti_k3_common.h

@@ -102,4 +102,5 @@ int k3_rproc_prepare(struct rproc *rproc);
 int k3_rproc_unprepare(struct rproc *rproc);
 int k3_rproc_start(struct rproc *rproc);
 int k3_rproc_stop(struct rproc *rproc);
+int k3_rproc_attach(struct rproc *rproc);
 #endif /* REMOTEPROC_TI_K3_COMMON_H */

drivers/remoteproc/ti_k3_dsp_remoteproc.c

@@ -58,17 +58,6 @@ static int k3_dsp_rproc_start(struct rproc *rproc)
 	return 0;
 }
 
-/*
- * Attach to a running DSP remote processor (IPC-only mode)
- *
- * This rproc attach callback is a NOP. The remote processor is already booted,
- * and all required resources have been acquired during probe routine, so there
- * is no need to issue any TI-SCI commands to boot the DSP core. This callback
- * is invoked only in IPC-only mode and exists because rproc_validate() checks
- * for its existence.
- */
-static int k3_dsp_rproc_attach(struct rproc *rproc) { return 0; }
-
 /*
  * Detach from a running DSP remote processor (IPC-only mode)
  *
@@ -172,7 +161,7 @@ static void *k3_dsp_rproc_da_to_va(struct rproc *rproc, u64 da, size_t len, bool
 static const struct rproc_ops k3_dsp_rproc_ops = {
 	.start			= k3_dsp_rproc_start,
 	.stop			= k3_rproc_stop,
-	.attach			= k3_dsp_rproc_attach,
+	.attach			= k3_rproc_attach,
 	.detach			= k3_dsp_rproc_detach,
 	.kick			= k3_rproc_kick,
 	.da_to_va		= k3_dsp_rproc_da_to_va,

drivers/remoteproc/ti_k3_m4_remoteproc.c

@@ -244,18 +244,6 @@ static void k3_m4_release_tsp(void *data)
 	ti_sci_proc_release(tsp);
 }
 
-/*
- * Attach to a running M4 remote processor (IPC-only mode)
- *
- * The remote processor is already booted, so there is no need to issue any
- * TI-SCI commands to boot the M4 core. This callback is used only in IPC-only
- * mode.
- */
-static int k3_m4_rproc_attach(struct rproc *rproc)
-{
-	return 0;
-}
-
 /*
  * Detach from a running M4 remote processor (IPC-only mode)
  *
@@ -273,7 +261,7 @@ static const struct rproc_ops k3_m4_rproc_ops = {
 	.unprepare = k3_rproc_unprepare,
 	.start = k3_rproc_start,
 	.stop = k3_rproc_stop,
-	.attach = k3_m4_rproc_attach,
+	.attach = k3_rproc_attach,
 	.detach = k3_m4_rproc_detach,
 	.kick = k3_rproc_kick,
 	.da_to_va = k3_m4_rproc_da_to_va,

drivers/remoteproc/ti_k3_r5_remoteproc.c

@@ -559,17 +559,6 @@ static int k3_r5_rproc_stop(struct rproc *rproc)
 	return ret;
 }
 
-/*
- * Attach to a running R5F remote processor (IPC-only mode)
- *
- * The R5F attach callback is a NOP. The remote processor is already booted, and
- * all required resources have been acquired during probe routine, so there is
- * no need to issue any TI-SCI commands to boot the R5F cores in IPC-only mode.
- * This callback is invoked only in IPC-only mode and exists because
- * rproc_validate() checks for its existence.
- */
-static int k3_r5_rproc_attach(struct rproc *rproc) { return 0; }
-
 /*
  * Detach from a running R5F remote processor (IPC-only mode)
  *
@@ -1059,7 +1048,7 @@ static int k3_r5_rproc_configure_mode(struct k3_rproc *kproc)
 		kproc->rproc->ops->unprepare = NULL;
 		kproc->rproc->ops->start = NULL;
 		kproc->rproc->ops->stop = NULL;
-		kproc->rproc->ops->attach = k3_r5_rproc_attach;
+		kproc->rproc->ops->attach = k3_rproc_attach;
 		kproc->rproc->ops->detach = k3_r5_rproc_detach;
 		kproc->rproc->ops->get_loaded_rsc_table =
 						k3_r5_get_loaded_rsc_table;