* [PATCH v2 1/2] drm/imagination: Define packed BVNCs in the uapi
2026-03-20 15:22 [PATCH v2 0/2] drm/imagination: GPU_ID-related cleanups Matt Coster
@ 2026-03-20 15:22 ` Matt Coster
2026-03-21 17:38 ` Claude review: " Claude Code Review Bot
2026-03-20 15:22 ` [PATCH v2 2/2] drm/imagination: Add PVR_GPU_ID_FMT to format pvr_gpu_id Matt Coster
2026-03-21 17:38 ` Claude review: drm/imagination: GPU_ID-related cleanups Claude Code Review Bot
2 siblings, 1 reply; 6+ messages in thread
From: Matt Coster @ 2026-03-20 15:22 UTC (permalink / raw)
To: Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, David Airlie,
Simona Vetter
Cc: Frank Binns, Brajesh Gupta, Alessio Belle, Alexandru Dadu,
dri-devel, linux-kernel, Matt Coster
Using the uapi-safe __GENMASK_ULL(), we can stably define the layout of
64-bit packed BVNCs. These defs replace the replicated doc comment that
appears all over the place.
Signed-off-by: Matt Coster <matt.coster@imgtec.com>
---
Changes in v2:
- Add _CONST variant of PVR_PACKED_BVNC() for use in case statements.
This fixes the build issue reported by the test bot[1][2]
- Link to v1: https://patch.msgid.link/20260206-bvnc-cleanup-v1-1-f3c818541fbe@imgtec.com
[1]: https://lore.kernel.org/r/202602070204.PjaKNSpZ-lkp@intel.com/
[2]: https://lore.kernel.org/r/202602070500.zo0DrH6U-lkp@intel.com/
---
drivers/gpu/drm/imagination/pvr_device.c | 6 ++---
drivers/gpu/drm/imagination/pvr_device.h | 43 +++++++++++++-------------------
include/uapi/drm/pvr_drm.h | 14 +++++------
3 files changed, 27 insertions(+), 36 deletions(-)
diff --git a/drivers/gpu/drm/imagination/pvr_device.c b/drivers/gpu/drm/imagination/pvr_device.c
index f58bb66a6327..9b26585a42bf 100644
--- a/drivers/gpu/drm/imagination/pvr_device.c
+++ b/drivers/gpu/drm/imagination/pvr_device.c
@@ -547,11 +547,11 @@ static enum pvr_gpu_support_level
pvr_gpu_support_level(const struct pvr_gpu_id *gpu_id)
{
switch (pvr_gpu_id_to_packed_bvnc(gpu_id)) {
- case PVR_PACKED_BVNC(33, 15, 11, 3):
- case PVR_PACKED_BVNC(36, 53, 104, 796):
+ case PVR_PACKED_BVNC_CONST(33, 15, 11, 3):
+ case PVR_PACKED_BVNC_CONST(36, 53, 104, 796):
return PVR_GPU_SUPPORTED;
- case PVR_PACKED_BVNC(36, 52, 104, 182):
+ case PVR_PACKED_BVNC_CONST(36, 52, 104, 182):
return PVR_GPU_EXPERIMENTAL;
default:
diff --git a/drivers/gpu/drm/imagination/pvr_device.h b/drivers/gpu/drm/imagination/pvr_device.h
index d51c57cf9332..55d8ff11d507 100644
--- a/drivers/gpu/drm/imagination/pvr_device.h
+++ b/drivers/gpu/drm/imagination/pvr_device.h
@@ -14,7 +14,7 @@
#include <drm/drm_file.h>
#include <drm/drm_mm.h>
-#include <linux/bits.h>
+#include <linux/bitfield.h>
#include <linux/compiler_attributes.h>
#include <linux/compiler_types.h>
#include <linux/device.h>
@@ -470,6 +470,12 @@ struct pvr_file {
#define to_pvr_file(file) ((file)->driver_priv)
+#define __PVR_PACKED_BVNC(prep, b, v, n, c) \
+ (prep(DRM_PVR_BVNC_B, b) | \
+ prep(DRM_PVR_BVNC_V, v) | \
+ prep(DRM_PVR_BVNC_N, n) | \
+ prep(DRM_PVR_BVNC_C, c))
+
/**
* PVR_PACKED_BVNC() - Packs B, V, N and C values into a 64-bit unsigned integer
* @b: Branch ID.
@@ -477,39 +483,24 @@ struct pvr_file {
* @n: Number of scalable units.
* @c: Config ID.
*
- * The packed layout is as follows:
- *
- * +--------+--------+--------+-------+
- * | 63..48 | 47..32 | 31..16 | 15..0 |
- * +========+========+========+=======+
- * | B | V | N | C |
- * +--------+--------+--------+-------+
+ * The packed layout follows the bitfield defined by the DRM_PVR_BVNC_* macros.
*
* pvr_gpu_id_to_packed_bvnc() should be used instead of this macro when a
* &struct pvr_gpu_id is available in order to ensure proper type checking.
*
* Return: Packed BVNC.
*/
-/* clang-format off */
-#define PVR_PACKED_BVNC(b, v, n, c) \
- ((((u64)(b) & GENMASK_ULL(15, 0)) << 48) | \
- (((u64)(v) & GENMASK_ULL(15, 0)) << 32) | \
- (((u64)(n) & GENMASK_ULL(15, 0)) << 16) | \
- (((u64)(c) & GENMASK_ULL(15, 0)) << 0))
-/* clang-format on */
+#define PVR_PACKED_BVNC(b, v, n, c) __PVR_PACKED_BVNC(FIELD_PREP, b, v, n, c)
+
+/** PVR_PACKED_BVNC_CONST() - Compile-time equivalent of PVR_PACKED_BVNC(). */
+#define PVR_PACKED_BVNC_CONST(b, v, n, c) __PVR_PACKED_BVNC(FIELD_PREP_CONST, b, v, n, c)
/**
* pvr_gpu_id_to_packed_bvnc() - Packs B, V, N and C values into a 64-bit
* unsigned integer
* @gpu_id: GPU ID.
*
- * The packed layout is as follows:
- *
- * +--------+--------+--------+-------+
- * | 63..48 | 47..32 | 31..16 | 15..0 |
- * +========+========+========+=======+
- * | B | V | N | C |
- * +--------+--------+--------+-------+
+ * The packed layout follows the bitfield defined by the DRM_PVR_BVNC_* macros.
*
* This should be used in preference to PVR_PACKED_BVNC() when a &struct
* pvr_gpu_id is available in order to ensure proper type checking.
@@ -525,10 +516,10 @@ pvr_gpu_id_to_packed_bvnc(const struct pvr_gpu_id *gpu_id)
static __always_inline void
packed_bvnc_to_pvr_gpu_id(u64 bvnc, struct pvr_gpu_id *gpu_id)
{
- gpu_id->b = (bvnc & GENMASK_ULL(63, 48)) >> 48;
- gpu_id->v = (bvnc & GENMASK_ULL(47, 32)) >> 32;
- gpu_id->n = (bvnc & GENMASK_ULL(31, 16)) >> 16;
- gpu_id->c = bvnc & GENMASK_ULL(15, 0);
+ gpu_id->b = FIELD_GET(DRM_PVR_BVNC_B, bvnc);
+ gpu_id->v = FIELD_GET(DRM_PVR_BVNC_V, bvnc);
+ gpu_id->n = FIELD_GET(DRM_PVR_BVNC_N, bvnc);
+ gpu_id->c = FIELD_GET(DRM_PVR_BVNC_C, bvnc);
}
int pvr_device_init(struct pvr_device *pvr_dev);
diff --git a/include/uapi/drm/pvr_drm.h b/include/uapi/drm/pvr_drm.h
index ccf6c2112468..72f3f90560cf 100644
--- a/include/uapi/drm/pvr_drm.h
+++ b/include/uapi/drm/pvr_drm.h
@@ -6,6 +6,7 @@
#include "drm.h"
+#include <linux/bits.h>
#include <linux/const.h>
#include <linux/types.h>
@@ -113,6 +114,11 @@ struct drm_pvr_obj_array {
* DOC: PowerVR IOCTL DEV_QUERY interface
*/
+#define DRM_PVR_BVNC_B __GENMASK_ULL(63, 48)
+#define DRM_PVR_BVNC_V __GENMASK_ULL(47, 32)
+#define DRM_PVR_BVNC_N __GENMASK_ULL(31, 16)
+#define DRM_PVR_BVNC_C __GENMASK_ULL(15, 0)
+
/**
* struct drm_pvr_dev_query_gpu_info - Container used to fetch information about
* the graphics processor.
@@ -125,13 +131,7 @@ struct drm_pvr_dev_query_gpu_info {
* @gpu_id: GPU identifier.
*
* For all currently supported GPUs this is the BVNC encoded as a 64-bit
- * value as follows:
- *
- * +--------+--------+--------+-------+
- * | 63..48 | 47..32 | 31..16 | 15..0 |
- * +========+========+========+=======+
- * | B | V | N | C |
- * +--------+--------+--------+-------+
+ * value using the DRM_PVR_BVNC_* bitmasks.
*/
__u64 gpu_id;
--
2.53.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 2/2] drm/imagination: Add PVR_GPU_ID_FMT to format pvr_gpu_id
2026-03-20 15:22 [PATCH v2 0/2] drm/imagination: GPU_ID-related cleanups Matt Coster
2026-03-20 15:22 ` [PATCH v2 1/2] drm/imagination: Define packed BVNCs in the uapi Matt Coster
@ 2026-03-20 15:22 ` Matt Coster
2026-03-21 17:38 ` Claude review: " Claude Code Review Bot
2026-03-21 17:38 ` Claude review: drm/imagination: GPU_ID-related cleanups Claude Code Review Bot
2 siblings, 1 reply; 6+ messages in thread
From: Matt Coster @ 2026-03-20 15:22 UTC (permalink / raw)
To: Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, David Airlie,
Simona Vetter
Cc: Frank Binns, Brajesh Gupta, Alessio Belle, Alexandru Dadu,
dri-devel, linux-kernel, Matt Coster
There are currently two different combinations of format specifiers used to
print a struct pvr_gpu_id, one using %i and one using %d. Both of these
are technically incorrect since the components are stored as u16.
Introduce macros to simplify and correct the formatting of these values:
- PVR_GPU_ID_FMT: A pre-constructed format string fragment, in the style
of PRIu32.
- PVR_GPU_ID_FMT_ARGS(): Accepts a &struct pvr_gpu_id and expands the
fields into appropriate format arguments to be used with PVR_GPU_ID_FMT.
- PVR_GPU_ID_FMT_ARGS_PACKED(): Accepts a packed GPU ID as a u64 and
extracts the components directly into appropriate format arguments to
be used with PVR_GPU_ID_FMT.
Signed-off-by: Matt Coster <matt.coster@imgtec.com>
---
Changes in v2:
- Simplify the change made to pvr_fw_validate()
- Link to v1: https://patch.msgid.link/20260206-bvnc-cleanup-v1-2-f3c818541fbe@imgtec.com
---
drivers/gpu/drm/imagination/pvr_device.c | 4 ++--
drivers/gpu/drm/imagination/pvr_device.h | 6 ++++++
drivers/gpu/drm/imagination/pvr_fw.c | 9 +++------
3 files changed, 11 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/imagination/pvr_device.c b/drivers/gpu/drm/imagination/pvr_device.c
index 9b26585a42bf..263d1badacf3 100644
--- a/drivers/gpu/drm/imagination/pvr_device.c
+++ b/drivers/gpu/drm/imagination/pvr_device.c
@@ -362,8 +362,8 @@ pvr_build_firmware_filename(struct pvr_device *pvr_dev, const char *base,
{
struct pvr_gpu_id *gpu_id = &pvr_dev->gpu_id;
- return kasprintf(GFP_KERNEL, "%s_%d.%d.%d.%d_v%d.fw", base, gpu_id->b,
- gpu_id->v, gpu_id->n, gpu_id->c, major);
+ return kasprintf(GFP_KERNEL, "%s_" PVR_GPU_ID_FMT "_v%d.fw", base,
+ PVR_GPU_ID_FMT_ARGS(gpu_id), major);
}
static void
diff --git a/drivers/gpu/drm/imagination/pvr_device.h b/drivers/gpu/drm/imagination/pvr_device.h
index 55d8ff11d507..54e3e947e60e 100644
--- a/drivers/gpu/drm/imagination/pvr_device.h
+++ b/drivers/gpu/drm/imagination/pvr_device.h
@@ -53,6 +53,12 @@ struct pvr_gpu_id {
u16 b, v, n, c;
};
+#define PVR_GPU_ID_FMT "%u.%u.%u.%u"
+#define PVR_GPU_ID_FMT_ARGS(gpu_id) (gpu_id)->b, (gpu_id)->v, (gpu_id)->n, (gpu_id)->c
+#define PVR_GPU_ID_FMT_ARGS_PACKED(gpu_id) \
+ (u32)FIELD_GET(DRM_PVR_BVNC_B, gpu_id), (u32)FIELD_GET(DRM_PVR_BVNC_V, gpu_id), \
+ (u32)FIELD_GET(DRM_PVR_BVNC_N, gpu_id), (u32)FIELD_GET(DRM_PVR_BVNC_C, gpu_id)
+
/**
* struct pvr_fw_version - Firmware version information
* @major: Major version number.
diff --git a/drivers/gpu/drm/imagination/pvr_fw.c b/drivers/gpu/drm/imagination/pvr_fw.c
index 288516dc2560..0b1c2a0d950c 100644
--- a/drivers/gpu/drm/imagination/pvr_fw.c
+++ b/drivers/gpu/drm/imagination/pvr_fw.c
@@ -126,12 +126,9 @@ pvr_fw_validate(struct pvr_device *pvr_dev)
}
if (pvr_gpu_id_to_packed_bvnc(&pvr_dev->gpu_id) != header->bvnc) {
- struct pvr_gpu_id fw_gpu_id;
-
- packed_bvnc_to_pvr_gpu_id(header->bvnc, &fw_gpu_id);
- drm_err(drm_dev, "FW built for incorrect GPU ID %i.%i.%i.%i (expected %i.%i.%i.%i)\n",
- fw_gpu_id.b, fw_gpu_id.v, fw_gpu_id.n, fw_gpu_id.c,
- pvr_dev->gpu_id.b, pvr_dev->gpu_id.v, pvr_dev->gpu_id.n, pvr_dev->gpu_id.c);
+ drm_err(drm_dev, "FW built for incorrect GPU ID " PVR_GPU_ID_FMT " (expected " PVR_GPU_ID_FMT ")\n",
+ PVR_GPU_ID_FMT_ARGS_PACKED(header->bvnc),
+ PVR_GPU_ID_FMT_ARGS(&pvr_dev->gpu_id));
return -EINVAL;
}
--
2.53.0
^ permalink raw reply related [flat|nested] 6+ messages in thread