This is a note to let you know that I've just added the patch titled
accel/ivpu: Use cached buffers for FW loading
to the 6.5-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
accel-ivpu-use-cached-buffers-for-fw-loading.patch
and it can be found in the queue-6.5 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d53162f7ce5305511d121711bfb875accbfb833d
Author: Karol Wachowski <karol.wachowski@xxxxxxxxxxxxxxx>
Date: Tue Sep 26 14:09:43 2023 +0200
accel/ivpu: Use cached buffers for FW loading
[ Upstream commit 645d694559cab36fe6a57c717efcfa27d9321396 ]
Create buffers with cache coherency on the CPU side (write-back) while
disabling snooping on the VPU side. These buffers require an explicit
cache flush after each CPU-side modification.
Configuring pages as write-combined may introduce significant delays,
potentially taking hundreds of milliseconds for 64 MB buffers.
Added internal DRM_IVPU_BO_NOSNOOP mask which disables snooping on the
VPU side. Allocate FW runtime memory buffer (64 MB) as cached with
snooping-disabled.
This fixes random long FW loading times and boot params memory
corruption on warmboot (due to missed wmb).
Fixes: 02d5b0aacd05 ("accel/ivpu: Implement firmware parsing and booting")
Signed-off-by: Karol Wachowski <karol.wachowski@xxxxxxxxxxxxxxx>
Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka@xxxxxxxxxxxxxxx>
Reviewed-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20230926120943.GD846747@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/accel/ivpu/ivpu_fw.c b/drivers/accel/ivpu/ivpu_fw.c
index f58951a0d81b1..93c69aaa6218d 100644
--- a/drivers/accel/ivpu/ivpu_fw.c
+++ b/drivers/accel/ivpu/ivpu_fw.c
@@ -195,7 +195,8 @@ static int ivpu_fw_mem_init(struct ivpu_device *vdev)
if (ret)
return ret;
- fw->mem = ivpu_bo_alloc_internal(vdev, fw->runtime_addr, fw->runtime_size, DRM_IVPU_BO_WC);
+ fw->mem = ivpu_bo_alloc_internal(vdev, fw->runtime_addr, fw->runtime_size,
+ DRM_IVPU_BO_CACHED | DRM_IVPU_BO_NOSNOOP);
if (!fw->mem) {
ivpu_err(vdev, "Failed to allocate firmware runtime memory\n");
return -ENOMEM;
@@ -272,7 +273,7 @@ int ivpu_fw_load(struct ivpu_device *vdev)
memset(start, 0, size);
}
- wmb(); /* Flush WC buffers after writing fw->mem */
+ clflush_cache_range(fw->mem->kvaddr, fw->mem->base.size);
return 0;
}
@@ -374,6 +375,7 @@ void ivpu_fw_boot_params_setup(struct ivpu_device *vdev, struct vpu_boot_params
if (!ivpu_fw_is_cold_boot(vdev)) {
boot_params->save_restore_ret_address = 0;
vdev->pm->is_warmboot = true;
+ clflush_cache_range(vdev->fw->mem->kvaddr, SZ_4K);
return;
}
@@ -428,7 +430,7 @@ void ivpu_fw_boot_params_setup(struct ivpu_device *vdev, struct vpu_boot_params
boot_params->punit_telemetry_sram_size = ivpu_hw_reg_telemetry_size_get(vdev);
boot_params->vpu_telemetry_enable = ivpu_hw_reg_telemetry_enable_get(vdev);
- wmb(); /* Flush WC buffers after writing bootparams */
+ clflush_cache_range(vdev->fw->mem->kvaddr, SZ_4K);
ivpu_fw_boot_params_print(vdev, boot_params);
}
diff --git a/drivers/accel/ivpu/ivpu_gem.h b/drivers/accel/ivpu/ivpu_gem.h
index 6b0ceda5f2537..f4130586ff1b2 100644
--- a/drivers/accel/ivpu/ivpu_gem.h
+++ b/drivers/accel/ivpu/ivpu_gem.h
@@ -8,6 +8,8 @@
#include <drm/drm_gem.h>
#include <drm/drm_mm.h>
+#define DRM_IVPU_BO_NOSNOOP 0x10000000
+
struct dma_buf;
struct ivpu_bo_ops;
struct ivpu_file_priv;
@@ -83,6 +85,9 @@ static inline u32 ivpu_bo_cache_mode(struct ivpu_bo *bo)
static inline bool ivpu_bo_is_snooped(struct ivpu_bo *bo)
{
+ if (bo->flags & DRM_IVPU_BO_NOSNOOP)
+ return false;
+
return ivpu_bo_cache_mode(bo) == DRM_IVPU_BO_CACHED;
}
