[PATCH 1/2] drm/imagination: Collect KCCB initialisation
From: Alexandru Dadu
Date: Thu Sep 10 2026 - 03:57:51 EST
From: Matt Coster <matt.coster@xxxxxxxxxx>
There's one FW object attached to KCCB usage (the return buffer) that is
separately initialised in pvr_fw_init(). Move this initialisation to
pvr_kccb_init() alongside the initialisation of rest of the members of
struct pvr_device->kccb.
Signed-off-by: Matt Coster <matt.coster@xxxxxxxxxx>
Signed-off-by: Alexandru Dadu <alexandru.dadu@xxxxxxxxxx>
---
drivers/gpu/drm/imagination/pvr_ccb.c | 38 +++++++++++++++++++++++++++++++----
drivers/gpu/drm/imagination/pvr_fw.c | 17 +---------------
2 files changed, 35 insertions(+), 20 deletions(-)
diff --git a/drivers/gpu/drm/imagination/pvr_ccb.c b/drivers/gpu/drm/imagination/pvr_ccb.c
index b702d122d791..3b5942b674be 100644
--- a/drivers/gpu/drm/imagination/pvr_ccb.c
+++ b/drivers/gpu/drm/imagination/pvr_ccb.c
@@ -17,6 +17,7 @@
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/mutex.h>
+#include <linux/overflow.h>
#include <linux/types.h>
#include <linux/workqueue.h>
@@ -527,6 +528,7 @@ void pvr_kccb_wake_up_waiters(struct pvr_device *pvr_dev)
*/
void pvr_kccb_fini(struct pvr_device *pvr_dev)
{
+ pvr_fw_object_unmap_and_destroy(pvr_dev->kccb.rtn_obj);
pvr_ccb_fini(&pvr_dev->kccb.ccb);
WARN_ON(!list_empty(&pvr_dev->kccb.waiters));
WARN_ON(pvr_dev->kccb.reserved_count);
@@ -543,14 +545,42 @@ void pvr_kccb_fini(struct pvr_device *pvr_dev)
int
pvr_kccb_init(struct pvr_device *pvr_dev)
{
- pvr_dev->kccb.slot_count = 1 << ROGUE_FWIF_KCCB_NUMCMDS_LOG2_DEFAULT;
+ const u32 num_slots_log2 = ROGUE_FWIF_KCCB_NUMCMDS_LOG2_DEFAULT;
+ const u32 num_slots = 1 << num_slots_log2;
+ u32 rtn_size;
+ int err;
+
+ /*
+ * The inputs here are compile-time constants; there's no reason to try
+ * to gracefully handle overflow at runtime.
+ */
+ BUILD_BUG_ON(check_mul_overflow(num_slots, sizeof(*pvr_dev->kccb.rtn), &rtn_size));
+
+ pvr_dev->kccb.slot_count = num_slots;
INIT_LIST_HEAD(&pvr_dev->kccb.waiters);
pvr_dev->kccb.fence_ctx.id = dma_fence_context_alloc(1);
spin_lock_init(&pvr_dev->kccb.fence_ctx.lock);
- return pvr_ccb_init(pvr_dev, &pvr_dev->kccb.ccb,
- ROGUE_FWIF_KCCB_NUMCMDS_LOG2_DEFAULT,
- sizeof(struct rogue_fwif_kccb_cmd));
+ err = pvr_ccb_init(pvr_dev, &pvr_dev->kccb.ccb, num_slots_log2,
+ sizeof(struct rogue_fwif_kccb_cmd));
+ if (err)
+ return err;
+
+ /* Allocate memory for KCCB return slots. */
+ pvr_dev->kccb.rtn = pvr_fw_object_create_and_map(pvr_dev, rtn_size,
+ PVR_BO_FW_FLAGS_DEVICE_UNCACHED,
+ NULL, NULL, &pvr_dev->kccb.rtn_obj);
+ if (IS_ERR(pvr_dev->kccb.rtn)) {
+ err = PTR_ERR(pvr_dev->kccb.rtn);
+ goto err_ccb_fini;
+ }
+
+ return 0;
+
+err_ccb_fini:
+ pvr_ccb_fini(&pvr_dev->kccb.ccb);
+
+ return err;
}
/**
diff --git a/drivers/gpu/drm/imagination/pvr_fw.c b/drivers/gpu/drm/imagination/pvr_fw.c
index 850a3ec8e775..cec17352cf90 100644
--- a/drivers/gpu/drm/imagination/pvr_fw.c
+++ b/drivers/gpu/drm/imagination/pvr_fw.c
@@ -945,8 +945,6 @@ pvr_fw_init(struct pvr_device *pvr_dev)
[PVR_FW_PROCESSOR_TYPE_RISCV] = &pvr_fw_defs_riscv,
};
- u32 kccb_size_log2 = ROGUE_FWIF_KCCB_NUMCMDS_LOG2_DEFAULT;
- u32 kccb_rtn_size = (1 << kccb_size_log2) * sizeof(*pvr_dev->kccb.rtn);
struct pvr_fw_device *fw_dev = &pvr_dev->fw_dev;
int err;
@@ -981,18 +979,9 @@ pvr_fw_init(struct pvr_device *pvr_dev)
if (err)
goto err_kccb_fini;
- /* Allocate memory for KCCB return slots. */
- pvr_dev->kccb.rtn = pvr_fw_object_create_and_map(pvr_dev, kccb_rtn_size,
- PVR_BO_FW_FLAGS_DEVICE_UNCACHED,
- NULL, NULL, &pvr_dev->kccb.rtn_obj);
- if (IS_ERR(pvr_dev->kccb.rtn)) {
- err = PTR_ERR(pvr_dev->kccb.rtn);
- goto err_fwccb_fini;
- }
-
err = pvr_fw_create_structures(pvr_dev);
if (err)
- goto err_kccb_rtn_release;
+ goto err_fwccb_fini;
err = pvr_fw_start(pvr_dev);
if (err)
@@ -1014,9 +1003,6 @@ pvr_fw_init(struct pvr_device *pvr_dev)
err_destroy_structures:
pvr_fw_destroy_structures(pvr_dev);
-err_kccb_rtn_release:
- pvr_fw_object_unmap_and_destroy(pvr_dev->kccb.rtn_obj);
-
err_fwccb_fini:
pvr_ccb_fini(&pvr_dev->fwccb);
@@ -1047,7 +1033,6 @@ pvr_fw_fini(struct pvr_device *pvr_dev)
WRITE_ONCE(fw_dev->initialised, false);
pvr_fw_destroy_structures(pvr_dev);
- pvr_fw_object_unmap_and_destroy(pvr_dev->kccb.rtn_obj);
/*
* Ensure FWCCB worker has finished executing before destroying FWCCB. The IRQ handler has
--
2.43.0